Friday, December 20, 2013

Case(s) of adult bone length growth

Control F for (*NEW*) for two breakthrough studies from 2004-2005 that provides evidence that LSJL can work on adults provided the stimulating caused by bite jumpling appliances(any experts on dentistry?) is to LSJL and how similar the mandible is to a long bone such as the tibia.  These two studies have been enhanced with new figures and analysis.

It has been shown that there is endochondral ossification involved in both osteoarthritis and that occurs in normal aging.  Why doesn't this articular cartilage ossification result in height increase?  Maybe enhancing this process of the articular cartilage can result in height increase of course you'd have to find a way preserve the articular cartilage from fully ossifying to maintain joint integrity.

The following studies serve as a bit of a proof of concept for adult bone length increase by showing that the two most distal of the three finger bones can increase in length with age and that the skull bone can increase in length.

Here are some selections from a statement by Roy Wuthier, a retired scientist in regards to non-growth plate methods of bone growth:

"Not all bone growth occurs via growth plate-dependent mechanisms.  The growth of phalanx bone apparently is not totally dependent on growth plate elongation.  As you realize, appositional growth can be mediated via osteoblasts that reside under the periosteal membrane.  Thus in phalanx bones, both types of bone growth must contribute to their expansion during overall skeletal growth."<-so perhaps on the proximal end of the phalanx bone there may be a periosteal membrane despite being separated by articular cartilage.

"During typical long bone growth (elongation), you will note that the ends of the long bones (where the growth plates reside) have a larger cross-sectional area than occurs at the mid-shaft.  The cells that sculpt the shape of the long bones are the osteoclasts which have the ability to remove bone.  In fact in a genetic disease where osteoclast formation is suppressed, the shape of the long bones is almost "post-like" with no reduction in mid-shaft cross-sectional area."<-Perhaps the larger cross-sectional area of the epiphysis formed by growth plate growth facilitates osteoclast absorption.  Thus, osteoclasts may be able to remove bone that is generated by endochondral ossification at a fast enough rate such that there is no net bone length increase.  And, in ends of the bones not formed by growth plates don't have as large a cross-sectional area favoring absorption thus apposition at the ends of the bones is greater than osteoclast resorption.

A way to test this is with osteoclast inhibitors however articular cartilage endochondral ossification is slow and osteoclasts are needed for many functions.  You could elevate HGH levels which increases both bone formation and resorption thus allowing you to safely lower osteoclast levels.  HGH would also increase the rate of the growth so it could occur in a reasonable time frame.  And then see if articular cartilage endochondral ossification could make you taller.

Metacarpophalangeal length changes in humans during adulthood: A longitudinal study

Metacarpophalangeal refers to hand bones essentially.

"Total lengths of the 19 diaphyseal hand bones were measured from standardized radiographs of healthy American whites as young adults (ca. 21 years) and again at ca. 55 years of age. The four hand-bone rows exhibit distinctive length changes: Distal and middle phalanges continue to increase significantly in length{the distal phalange may have periosteum at the distal end of the bone so it may be able to grow by appositional growth but that is not true of of the middle phalange}, proximal phalanges constitute a transition zone of little change, and metacarpals uniformly decrease in length[there are three bones in a non thumb finger.  The end bone is the distal bone and the one closest to the the end is the proximal phalange.  The metacarpals are part of the hand.]. Clear-cut sex differences are noteworthy: Males change more (lose more in some bone rows, gain more in others) than females. Progressive elongation was greatest in the distal phalanges where apposition around the distal aspect (“tufting”) is not constrained by a joint or epiphysis. Loss of bone length in the metacarpals by subchondral resorption is consistent with documented reductions in activity levels and grip strength with age, as well as diminished joint spaces which alter loading of the joints."

The increase in bone length was about 0.34 mm per decade.

"To test for [the possibility that the bone length gain was due to residual gain due to growth plate growth], we partitioned the sample into those cases whose younger-adult age at examination was less than 25 years and those with a radiograph after 25 years of age. Using a two-way  factorial analysis of variance, grouping by age grade and sex, none of the 19 tests achieved statistical  significance. "

"In the distal and middle phalanges most of  the increase was accounted for by progressive apposition at the distal, epiphysis-free ends of the bones"

If you look at the phalanx x-rays you can see that distal ends of the bones do not have a growth plate.


Only the proximal(closest to the body) side has growth plates.  Maybe bone growth can be renewed if you remove the epiphysis somehow.  LSJL via fluid based shear strain may degrade some of the epiphysis allowing for new height growth.

"the distal phalanges, which exhibit appreciable increase, are unique in not being constrained distally by a joint or epiphysis"

"When cartilage thickness exceeds the critical dimensions that limit nutrition by diffusion, the cartilage cells hypertrophy and degenerate, the spaces become vascularized, and osteoblasts develop to initiate endochondral bone formation in the midst of the articular cartilage."

Continuing bone growth throughout life: A general phenomenon

"Cross-sectional data on 2799 subjects from five different populations and longitudinal data on 113 older adults indicate continuing adult bone growth in the second metacarpal. Similar 6-decade increases in the size of the cranium confirm continuing bone growth as a general phenomenon not necesarily related to weightbearing or flexion stress and representing an increase of approximately 10% in skeletal volume concomitant with the major age-associated decrease in skeletal mass."

"there is a small but completely systematic three-decade gain in metacarpal width at mid-shaft  in  both sexes  and all  five  populations  sampled"

The scientists reported an increase in skull length.

Extreme elongation of the transverse processes of the fifth lumbar vertebra: an unusual variant.

"The fifth lumbar vertebra has massive transverse processes that are continuous with the pedicle and encroach the body of the vertebra. These processes are mainly meant for the attachment of the iliolumbar ligament. With increasing age, the iliolumbar ligament can undergo secondary degenerative changes such as calcification, hyalinization, and myxoid degeneration. [We discovered an] extremely elongated transverse processes of the fifth lumbar vertebra in a 45-year-old woman who underwent surgery for an intervertebral disc herniation. This unusual variant may be caused by calcification of the iliolumbar ligament rather than a congenital anomaly."

Causing calcification of ligaments isn't really reproducible but it's still bone length increase in a 45 year old.

If you look figure 1A and 1B you can see that the increase in transverse process is insane with the elongated transverse process being about 3 times longer than the other bones.

"[There was] a calcified nodular lesion in the left pelvic cavity, suggesting the presence of a calcified uterine myoma[mesenchymal tumor]."

"the trabecular bone of the transverse processes have normal shape and length, and the compact bone is elongated."

"[There was] a large, extruded intervertebral disc on the right side, compressing the dural sac."

"the direction of elongation of the transverse process corresponded to the position of the iliolumbar ligament."  Thus providing evidence that the iliolumbar ligament was calcified.

"The iliolumbar ligament is attached to the tip and the anteroinferior aspect of the transverse processes of the fifth lumbar vertebra"<-So the ligament may have been used as a scaffold to grow the bone longer.  Maybe a ligament can be inserted into a long bone so you can grow taller forever.

"the iliolumbar ligament does not exist at birth, but develops gradually in the first decade and attains full differentiation only in the second decade."


Mechanical strain leads to condylar growth in adult rats.

"Mechanical strain produced by forward mandibular positioning was found to enhance mandibular condylar growth in experimental animals and in patients. [We] identify the changes in number and rate of the proliferating mesenchymal cells in mandibular condyles of adult rats and to correlate these changes to the expression of SOX9 and type II collagen under mechanical strain. Seventy-eight 120-day-old female Sprague-Dawley rats{rats generally stop growing at six months} were randomly allotted to six groups, nine animals in each experimental group according to different time points. Cell kinetic studies for expression of PCNA were used to identify number and rate of proliferating mesenchymal cells. Immunostaining of SOX9 and in situ hybridization of Col2a1 gene were carried out. Results showed a significant increase in number of replicating mesenchymal cells and proliferation rate. The expression of SOX9 was enhanced and Col2a1 gene transcript was then activated. The proliferative layer became thicker on experimental day 21. The thickness of chondroblast layer and chondrocyte layer showed significant increase from experimental day 14 to day 30. Mechanical strain produced by mandibular advancement in adult rats promotes the proliferation of mesenchymal cells. Under control of transcription factor SOX9, these mesenchymal cells are then committed to enter the chondrogenic route leading to condylar growth."

Producing proliferating of MSCs which then differentiate into chondrocytes via SOX9 is exactly what we're trying to accomplish with LSJL.

"mandibular advancement reactivates endochondral ossification in the posterior condyle and ultimately results in new bone formation in the condyle"

"In the adult patients treated with Herbst appliance this would be the result of a reactivation of cells of prechondroblast zone, thus representing an area of active condylar growth"

"continuous bite jumping devices induce morphological adaptation in the mandible especially the length of condylar head in adult rats"

"During mandibular growth, the condyle undergoes endochondral ossification and the condylar cartilage acts as a template for bone growth. However, in the adults, the remnant condylar cartilage serves more 'articular' function than 'growth' function. From growing to adults, the thickness of cartilage becomes thinner. It has been reported that the adult rat's condyle is covered by a thin layer of cartilage, which is composed of 2-3 layers of chondrocytes and there is no obvious hypertrophic layer in the cartilage since a weak staining of Type X collagen, the marker of endochondral ossification, was obscured. This result implies that adult rat condyle stops growth or becomes inactive of endochondral ossification. Bone growth in the condyle is closely related to cartilage formation in the growing rats"

"The fibrous zone of the condylar cartilage of adult rats is composed of several layers of flattened cells . The cells in the proliferative layer, which was densely packed, located beneath the fibrous layer . Underneath the proliferative layer, the cells became chondrospecific and flattened gradually. The extracellular matrix was positively stained with type II collagen and thus this layer was termed as "type II collagen positive layer" in the present stud which may represent the level of expression of type II collagen. The current study showed that the thickness of cartilage in posterior condyle was apparently affected by the bite-jumping device. Analysis showed the thickness of each layer of cartilage in controls was unchanged during the observation period. In the experimental group, there were significant changes observed in all the layers. The thickness of fibrous layer showed significant increase from day 14 of mandibular advancement and was maintained from day 30 to day 60 Mandibular advancement resulted in an increase in the thickness of the proliferative layer on day 21 which was then followed by a decrease to the level found in the matched controls. The thickness of type II collagen positive layer showed a significant increase from experimental day 14. The highest level was presented on experimental day 21 followed by a lower level on day 30. The level of expression of type II collagen expressed on day 60 returned to the level expressed in the controls."

"The population [of MSCs] in that of mandibular advancement groups was significantly increased on day 21" No differences were observed in the control group.

"In the control groups, only a few SOX9 positive cells existed in the proliferative layer. On experimental day 3, SOX9 positive cells were remarkably increased in the proliferative layer of experimental animals. On experimental day 21, the SOX9 positive cells were increased in both proliferative layer and chondroblast layer but no positive staining can be detected in the hypertrophic chondrocyte"

"mandibular advancement in adult rats resulted in increase in condylar growth as measured by a significant increase in: the number and rate of replicating mesenchymal cells; the expression of transcription factor SOX9, the factor that regulates mesenchymal cell differentiation into chondroblasts; the thickness of cartilage layers and finally increase in the amount of osteocytes that led to increase in the production of new bone in the adult condyles "

I'm not sure how much a forward biting device is analagous to LSJL.  Maybe someone more familiar with dentistry can help out.

"[The] significant increase in SOX9 expression level coincided with the rate of proliferation of mesenchymal cells"

It should be noted that the population of MSCs began to decline after thirty days.  That may be related to an adaptative response and indicates that there may need to be a deconditioning period with LSJL after 30 days.

" Each group consisted of nine rats with bite-jumping appliances and four untreated controls"

On this page is an example of a bite jumping appliance(It's the Herbst) mentioned earlier.

Here's the picture of experimental jaw versus control:


I'm planning on looking for ectopic signs of cartilage formation later as that is what we're trying to induce with LSJL.  However there is some blue staining(which means it's positive for cartilage) on A but it is very faint. Note though that the entire shape of B(experimental) is different than A(control) so there must be some mechanism to achieve that.

"Alcian blue-PAS staining showing the overview of rat's TMJ condyle at age of 141-day (experimental day 21). The thickness of cartilage in the posterior condyle is remarkably increased by mandibular advancement (B) than that of control (A). Two measurement frames are illustrated on (B), one for the measurement of thickness of layers (1104×811µm, black) and the other frame for the cell counting (547×402µm, red)."
Here's the ectopic chondrogenesis highlighted with GIMP(blue line):



Here's the Col2a1 expression areas:

"In situ hybridization showing the localization of type II collagen (Col2a1) mRNA (marked with arrow) in the condylar cartilage of control (A) and experimental animal (C.D) on experimental day 21. (D) is higher magnification of (C). In situ hybridization with sense probe shows no hybridization signal in the cartilage (B)."  So there was no active COL2A1 mRNA production in B which is the control.
Arrows point to two possible areas where the bone ends both are distant from the Col2a1 staining indicating that the new growth plate formation is within the bone thus providing evidence for proof of concept for LSJL to form new growth plates within bone.

Forward mandibular positioning enhances condylar adaptation in adult rats.

"The aim of this investigation was to assess quantitatively the adaptive changes in the condyles of adult rats to forward mandibular positioning. The level of types II and X collagen expressed in the condyles of adult rats was compared with that formed in response to forward mandibular positioning and the levels of expression were correlated to the amount of bone formed in response to mandibular advancement. Seventy-eight 120-day-old female Sprague-Dawley rats were included in this study. The rats were randomly allocated to six groups. Each group consisted of nine rats with bite-jumping devices and four untreated controls. The animals in each group were sacrificed on days 3, 7, 14, 21, 30, and 60. Immunostaining was used for the detection of types II and X collagen, while Alcian blue-PAS was used to observe the extracellular matrix and new bone formation. New cartilage was formed in the posterior condyle. The highest level of expression of types II and X collagen were present on day 21, the amount of increase was 247.99 and 540.08 per cent, respectively. The highest level of new bone formation was measured at day 30 of advancement when the amount of increase in new bone formation was 318.91 per cent. Forward mandibular positioning causes changes in the biophysical environment of the temporomandibular joint (TMJ) of adult rats that leads to condylar adaptation."

The study won't let me copy and paste. When I get a chance, I might print the paper out and scan the images in. Click on the link and look at figure 2 for new cartilage growth.  Note in figure 2a that the region of new cartilage formation pointed to by the arrow is disconnected from the rest the cartilage.  Also note that there is red staining in scattered quantities throughout the entirety of the epiphysis with the exception of that attached to the bone attached to the new red zone.

Note that in figure 1 there is staining for Type II Collagen deep within the epiphysis in the control group.

In figure 3a there is staining for Type II collagen throughout the entire bone.  If you look at figure five bone formed downward furthering the possibility that you can increase bone length via the articular cartilage.

Regional shape change in adult facial bone curvature with age.

"hree-dimensional semilandmarks representing the curvature of the orbits, zygomatic arches, nasal aperture, and maxillary alveolar process were collected from a cross-sectional cranial sample of mixed sex and ancestry (male and female; African- and European-American), partitioned into three age groups (young adult = 18-39; middle-aged = 40-59 years; and elderly = 60+ years). Each facial region's semilandmarks were aligned into a common coordinate system via generalized Procrustes superimposition. Regional variation in shape was then explored via a battery of multivariate statistical techniques. Age-related shape differences were detected in the orbits, zygomatic arches, and maxillary alveolar process."

"adult craniofacial curvature shape is not static throughout human life. Instead, age-related spatial modifications occur in various regions of the craniofacial skeleton."

"Increases in craniofacial dimensions such as facial height, mandibular length, bizygomatic and bigonial breadth, and head circumference, length, and breadth have been detected with advancing age"

Natural craniofacial changes in the third decade of life: a longitudinal study.

"Natural head position lateral cephalometric films and dental casts of 30 people (14 women and 16 men) were evaluated. The mean age at the beginning of the observation period was 22.35 years for the women and 22.19 years for the men, and the observation period was approximately 10 years. Cephalometric films were superimposed by the structural method, and the measurements of the dental casts were made with a digital caliper. All tracings were digitized, and changes in the 65 cephalometric and 10 dental cast measurements were evaluated statistically. In this early adult period, small changes were found in the craniofacial and craniocervical parameters; the changes were more significant in the women. The most significant changes were found in the vertical dimension. The total anterior face height increased in both genders, while the lower anterior face height increased significantly in the female group. Soft tissue measurements reflected the vertical skeletal changes. The retrusion of the upper lip was significant in the women, and the upper lip thickness decreased in both genders. In the dentoalveolar region, the main movement was eruption of the teeth. The overbite amount increased significantly only in the female group. All dental arch measurements decreased in both sexes. The decrease in the mandibular arch length discrepancy was significant in the men."

Thursday, October 31, 2013

Merger with Natural Height Growth dot Com

I will now be making all new posts over at Natural Height Growth.  I will still be maintaining this blog but mainly with technical/scientific stuff.  All new posts regarding LSJL results, the LSJL method, height increase supplements, and definitive advancements in height increase methodology will be at the NHG website.  But tangential, technical things will be on this website.

Also, the search feature on this site can search both Natural Height Growth and Heightquest.

Monday, July 8, 2013

Resveratrol - A Potential Height Increase Supplement

 Surprisingly Resveratrol is available for sale: 1000 MG Resveratrol Extreme Juice Capsules Resveratrol Juice capsules TM 3 Months 180 pills HIGHLY POTENT Pure Resveratrol pills. 3 MONTH GUARANTEE. TWICE AS POTENT AS many RESVERATROL, Resveratrol Juice Extreme.

Resveratrol has a similar structure to estrogen and may prevent binding of estrogen to various cells that would decrease growth.  Therefore, resveratrol may increase height if taken during development at the right dose.

 Resveratrol Treatment Delays Growth Plate Fusion and Improves Bone Growth in Female Rabbits

"Trans-resveratrol (RES), naturally produced by many plants, has a structure similar to synthetic estrogen diethylstilbestrol. Pre-pubertal ovary-intact New Zealand white rabbits received daily oral administration of either vehicle (control) or RES (200 mg/kg) until growth plate fusion occurred{We don't know if this will have the same effect on men}. Bone growth and growth plate size were longitudinally monitored by X-ray imaging, while at the endpoint, bone length was assessed by a digital caliper. In addition, pubertal ovariectomized (OVX) rabbits were treated with vehicle, RES or estradiol cypionate (positive control) for 7 or 10 weeks and fetal rat metatarsal bones were cultured in vitro with RES (0.03 µM–50 µM) and followed for up to 19 days. In ovary-intact rabbits, sixteen-week treatment with RES increased tibiae and vertebrae bone growth and subsequently improved final length. In OVX rabbits, RES delayed fusion of the distal tibia, distal femur and proximal tibia epiphyses and femur length and vertebral bone growth increased when compared with controls. RES-treated OVX rabbits had a wider distal femur growth plate, enlarged resting zone, increased number/size of hypertrophic chondrocytes, increased height of the hypertrophic zone, and suppressed chondrocyte expression of VEGF and laminin. In cultured fetal rat metatarsal bones, RES stimulated growth at 0.3 µM while at higher concentrations (10 μM and 50 μM) growth was inhibited. RES has the potential to improve longitudinal bone growth. The effect was associated with a delay of growth plate fusion resulting in increased final length. These effects were accompanied by a profound suppression of VEGF and laminin expression suggesting that impairment of growth plate vascularization might be an underlying mechanism."

Note that only the smallest dosage of Resveratrol had an anabolic effect on growth which is consistent with the view that estrogen has an equilibrium level for growth.  These rabbits were pre-puberty so estrogen levels should've been lower than puberty.  Since estrogen levels increase during puberty doses should increase during puberty as estrogen would be higher than equilibrium level.  It's hard to ascertain what that is for humans though.

"Trans-resveratrol (3, 5, 4′-trihydroxystilbene), is a polyphenol naturally produced by a variety of plants such as peanuts, berries, skin of red grapes in response to stress, injuries and infections."<-Does anyone have anecdotal accounts of tall people or groups that ate lots of peanuts, berries, or red grapes?  Or drink red wine?

"in weanling rats demonstrating that 6 days of treatment with very low doses of RES (1–100 μg/day) had no significant effect on radial bone growth"

The Rabbits were twelve weeks old.

"tibia length 111.6±0.6 mm in the RES group vs. 109.5±0.6 mm in control" over 8 weeks.  That's approximately a 5% increase in growth rate.  Vertebral height was increased as well.

"RES-treatment delayed the time of growth plate fusion in all studied growth plates."

"After 10 weeks, 33% of the animals in the RES group had unfused distal femur growth plates while only 10% of control animals had"

Surprisingly, RES decreased the number of proliferative chondrocytes per area in growth plates versus control but this is consistent with the view that Resveratrol delays growth plate senescence.

"chondrocyte expression of VEGF to be clearly suppressed in RES-treated rabbits as compared to controls (265±54 vs. 626±50 VEGF positive cells/mm2) while in the E2 group VEGF expression was similar as in controls (632±153 vs. 626±50 positive cells/mm2). Also the expression of laminin was decreased in the RES-treated group as compared to controls (17.7±0.6 vs. 27.4±1.04 positive cells/mm2;). In contrast, laminin expression was elevated in E2 treated animals (44.4±0.8 vs. 27.4±1.04 positive cells/mm2 in control)"

"RES significantly improves bone growth by delaying the process of epiphyseal fusion in female animals. Animals treated with RES had wider growth plates with enlarged resting zone, fewer proliferative chondrocytes, increased number and size of hypertrophic chondrocytes and markedly suppressed VEGF and laminin expression."

Friday, July 5, 2013

Zone of Ranvier

In the studies of physeal briding, the zone of ranvier's unobstruction was critical for normal longitudinal bone growth without angular deformities. The zone of ranvier is also placed on the longitudinal side of the bone so may be key to LSJL.  As the zone of ranvier is on the longitudinal side, it can be more easily accessed than something that's within the bone itself.  Studying how much the zone of ranvier is maintained post diaphyseal/epiphyseal fusion may be key to forming new growth plates.  If the zone of ranvier is maintained to any degree post fusion than it may be possible to restore growth.

Here's an image of the zone of ranvier:
From Normal Bone Formation.

"The growth plate may be divided anatomically into three components: a cartilaginous component, itself divided into various histologic zones; a bony component, metaphysis; and a fibrous component surrounding the periphery of the plate comprising the groove of Ranvier and the perichondrial ring of LaCroix."

"The epiphyseal artery supplies the epiphysis, or the secondary center of ossification, which itself is not part of the growth plate. Small branches arise at right angles to the main epiphyseal artery in the epiphysis and pass through small cartilage canals in the reserve zone to terminate at the top of the cell columns in the proliferative zone. Each small branch from the epiphyseal artery arborizes in rakelike fashion to supply the top portion of from four to ten cell columns. The proliferative zone, therefore, is well supplied with blood. None of the branches from the epiphyseal arteries penetrate the cartilage portion of the growth plate beyond the uppermost part of the proliferative zone; that is, no vessels pass through the proliferative zone to supply the hypertrophic zone."

"The reserve zone lies immediately adjacent to the secondary bony epiphysis. Various terms have been applied to this zone, including resting zone, zone of small-size cartilage cells, and germinal zone. However, these cells are not resting, are not small in comparison with the cells in the proliferative zone, and they are not germinal cells. They appear to store lipid and other materials and perhaps are held in reserve for later nutritional requirements. If that is true, the term reserve zone may be appropriate. The cells in this zone are spherical, exist singly or in pairs, are relatively few when compared with the number of cells in other zones, and are separated from each other by more extracellular matrix than are cells in any other zone. The cells in the reserve zone are approximately the same size as the cells in the proliferative zone. The cytoplasm exhibits a positive staining reaction for glycogen.  These cells contain abundant endoplasmic reticulum, a clear indication that they are actively synthesizing protein. They contain more lipid bodies and vacuoles than do cells in other zones but contain less glucose-6-phosphate dehydrogenase, lactic dehydrogenase, malic dehydrogenase, and phosphoglucoisomerase. The zone also contains the lowest amount of alkaline and acid phosphatase, total and inorganic phosphate, calcium, chloride, potassium, and magnesium. The matrix in the reserve zone contains less lipid, glycosaminoglycan, protein polysaccharide, moisture, and ash than the matrix in any other zone. It exhibits less incorporation of radiosulfur (35S) than any other zone and also shows less Iysozyme activity than the other zones. It contains the highest content of hydroxyproline of any zone in the plate. Collagen fibrils in the matrix exhibit random distribution and orientation. Matrix vesicles are also seen in the matrix, but they are fewer than in other zones. The matrix shows a positive histochemical reaction for the presence of a neutral mucopolysaccharide or an aggregated proteoglycan."

Another image of the Zone of Ranvier and LaCroix:


"The perichondrial ring is a dense fibrous band that encircles the growth plate at the bone-cartilage junction and in which collagen fibers run vertically, obliquely, and circumferentially. It is continuous at one end with the group of fibroblasts and collagen fibers in the ossification groove and at the other end with the periosteum and subperiosteal bone of the metaphysis. In rodents, rabbits, and dogs, the innermost layer of the perichondrial ring consists of bone that may or may not be attached to the subperiosteal bone of the metaphysis. This cylindrical sheath of bone may not be present in all species at all ages in all growth plates. For instance, it is not present in the proximal femur in the human at any age. " Whether or not bone is present in the perichondrial ring, there is no doubt that the ring provides mechanical support for the otherwise weak bone-cartilage junction of the growth plate"

If we can somehow prove that the zone of Ranvier is retained post fusion then that would be a huge breakthrough for forming new growth plates.

Identification of a stem cell niche in the zone of Ranvier within the knee joint.

"A superficial lesion of the articular cartilage does not spontaneously self-repair and has been suggested to be partly due to lack of progenitor cells within the joint that can reach the site of injury. To study whether progenitor cells are present within the joint, 3-month-old New Zealand white rabbits were exposed to bromodeoxyuridine (BrdU) for 12 consecutive days and were then sacrificed 4, 6, 10, 14, 28 and 56 days after the first BrdU administration. Presence of BrdU and localization of progenitor markers were detected. After 10 days of BrdU exposure, BrdU-positive cells, i.e. proliferating cells, were abundantly detected in the epiphyseal plate, the perichondrial groove of Ranvier, and in all zones of the articular cartilage{so the rabbits were skeltally immature}. After a wash-out period, BrdU-positive cells were still present, i.e. those considered to be progenitor cells, in these regions of the knee except for the proliferative zone of the epiphyseal plate. Cells in the perichondrial groove of Ranvier were further positive for several markers associated with progenitor cells and stem cell niches, including Stro-1, Jagged1, and BMPr1a. A small population of progenitor cells is present in the perichondrial groove of Ranvier as well as within the articular cartilage in the knee. The perichondrial groove of Ranvier demonstrates the properties of a stem cell niche."

"The growth plate is surrounded by an encircling fibrochondrosseous structure. This anatomical structure consists of the zone of Ranvier and the ring of LaCroix. The area [harbors] prechondrocytes responsible for the circumferential growth of cartilage."

"perichondrial cells from the ring of LaCroix, which is a fibrous band that surrounds the groove of Ranvier and is continuous with the periosteum of the metaphysis, serve as a reservoir for precartilaginous cells in the germinal layer of the epiphyseal growth plate"

"A larger number of BrdU-positive cells in the epiphyseal plate[were] near the perichondrial groove of Ranvier than in the central area of the epiphyseal plate. [Cells may migrate] from the perichondrial groove of Ranvier into the epiphysis."<-Based on how much the Zone of Ranvier is retained this can be used to form new growth plates.


"The Janus kinase (Jak)-signal transducer and activator of transcription (STAT)-5 pathway is activated by GH, so we developed a method to visualize nuclear Stat5b and phosphorylated Stat5 in single cells in response to a pulse of GH. Hep2 cells did not show a Stat5 phosphorylation (pY-Stat5) response to GH except in cells transfected to express GH receptors. ATDC5 cells express GH receptors and showed GH-induced pY-Stat5 responses, which varied with their state of chondrocyte differentiation. In vivo, Stat5b(+ve) nuclei were seen in the resting and prehypertrophic chondrocytes of the growth plate. After a single ip pulse of human GH or mouse GH, but not prolactin, pY-Stat5 responses were visible in cells in the resting zone and groove of Ranvier, 10-45 min later{Maybe LSJL mimics these pulses}. Prehypertrophic chondrocytes showed no pY-Stat5 response to GH. GH target cells were also identified in other tissues, and a marked variability in spatiotemporal pY-Stat5 responses was evident. Endogenous hepatic pY-Stat5 was detected in mice with intact GH secretion but only during a GH pulse. Fasting and chronic exposure to GH attenuated the pY-Stat5 response to an acute GH injection.  pY-Stat5 responses to GH vary in time and space, are sensitive to nutritional status, and may be inhibited by prior GH exposure{GH needs to be cycled}. GH [regulates] the fate of immature chondrocytes."

"Although Stat1, -3, -5a, and -5b can all be activated by GH, Stat5b is the major target for growth promotion because it is uniquely responsive to the temporal pattern of plasma GH"

Figure
Groove of Ranvier identified in A.

Development of the distal femoral epiphysis: a microscopic morphological investigation of the zone of Ranvier.

"The distal femoral epiphysis, physis, and contiguous metaphysis were examined radiographically, morphologically, and histologically in 97 human specimens ranging in age from 9 prenatal weeks to 16 postnatal years. The earliest development of the femoral anlage was characterized by patterns of appositional and interstitial chondrogenesis throughout its entire structure. Once central endochondral ossification began, chondrogenic interstitial and appositional growth became regionally restricted to the femoral epiphyses. Interstitial chondrogenesis became limited to the germinal region of the developing physis, and appositional chondrogenesis was restricted to the region of loosely packed cells of the perichondrial ossification zone of Ranvier. Appositional chondrogenesis within the perichondrium appears to make its greatest contribution to transverse expansion of the distal femoral epiphysis during the first 5 months of gestation. After the sixth month of gestation, the perichondrial appositional growth contribution appears to decline steadily."

Couldn't get this full study which is unfortunate because it could give us insight into whether the Zone of Ranvier fuses or not.

According to The expression of the nuclear oncogenes c-myc and c-jun in the groove of Ranvier of the rabbit growth plate., cells in the Groove of Ranvier are positive for c-Myc and c-Jun.

Role of the ossification groove of Ranvier in normal and pathologic bone growth: a review.

"cells in the groove [of Ranvier] and adjacent periosteum contain type II collagen messenger RNA (mRNA) characteristic of cartilage"

"The normal interstitial growth of the reserve cell zone or the germinal layer of the growth plate leads to migration of cells toward the periphery, where some cells give rise to new cell columns inside the groove. Other cells have their structure changed and enter the inner cell layer of the well-vascularized tissue in the ossiffication groove. These cells lose their surrounding ground substance entering the groove but retain their ability to synthesize type II collagen mRNA. With continued growth of the bone, the cells are left behind and give rise to osteoblasts and bone."

 The periphysis and its effect on the metaphysis: I. Definition and normal radiographic pattern

"The zone of Ranvier and the ring of LaCroix, together with the membranous bone bark they produce, are termed the periphysis in order to emphasize their normal effect (the metaphyseal collar) on the metaphysis of the infant and young child. In the first 7 years of life, the normal collar at the wrist is 1-3 mm wide. The step-off between the metaphyseal collar and the curvilinear metaphysis, at the margin of the periphysis, should not be mistaken for abuse fracture. The periphyseal bone bark may be radiologically visible at the edge of the physis at the distal ulna in 9% of infants and should not be mistaken for fracture or rickets." 

"The periphysis surrounds the growth plate (physis) of tubular bones and also the most recently formed several millimeters of metaphysis in infants. It is a fibrochondroosseous structure that (a) appears to maintain the transverse diameter of the physis and at the same time (b) allows gradual transverse growth of the same physis. That portion of the periphysis adjacent to the physis has been described under the names zone or groove of Ranvier, that portion adjacent to the metaphysis, as the
ring of LaCroix.
Histologically, the Ranvier and LaCroix zones are a single structure; both lay down a continuous thin layer of bone, termed bone bark, centrally at the periphery of the physis and metaphysis. This bone bark is produced by membranous, rather than enchondral, bone formation. In the first several years of life that portion of the metaphysis surrounded by the periphysis has a flat, longitudinally directed periphery on radiographs, rather than a smooth curved contour characteristic of the margins of other portions of the metaphysis. The result is the short metaphyseal collar"

"The periphysis [restrains] longitudinal widening of the physis."

Cartilage Tissue Engineering; the search for chondrogenic progenitor cells and associated signalling pathways

"Stem cells [are] not only in the articular cartilage but also in the groove of Ranvier located in the periphery of the epiphyseal growth plate.
The groove of Ranvier exhibited properties as a stem cell niche structure. Further biopsies
from human normal articular cartilage, as well as regenerated and repaired cartilage after ACI
were studied. The human normal articular cartilage demonstrated expression of the stem cell
associated markers STRO-1 and Bcrp1 in cells in the superficial zone, and activity of the
fundamental Wnt (Wingless-related proteins) and Notch signalling pathways. The distribution
showed a distinct zonal pattern in the normal cartilage. In biopsies from regenerated cartilage
with almost normal histological architecture, the markers and pathways studied demonstrated a
distinct zonal pattern similar to that in normal cartilage."

"in articular cartilage there are subpopulations of cells with mesenchymal stem cell properties"

"From the lateral plate mesoderm, undifferentiated mesenchymal cells begin to migrate to areas destined to become bone, followed by tight packing of the cells, known as mesenchymal condensation. The cartilage anlagen for the future skeletal elements have now formed. Cellular condensation is associated with increased cell to cell contact and increased cell to matrix interaction. Molecules taking part in the intercellular communication are e.g. neural cell adhesion molecule (N-CAM), Ncadherin, tenascin, versican, fibronectin and gap junctions (connexin 42 and 43),"

"The first sign of joint formation is the appearance of an interzone. The interzone cells gives rise to the articular layer of the future long bones while the chondrocytes developing from the mesenchymal condensation are assumed to be a part of epiphyseal growth plate and to take part in endochondral ossification, these cells are called transient chondrocytes. It has been unclear whether the interzone cells derive from transdifferentiation of local prechondrocytes into interzone cells or if there is migration of mesenchymal cells into the joint site, or a combination"

"It[perichondrial groove of Raniver] is a circumferential anatomical structure in the periphery of the epiphyseal growth plate and consists of the zone of Ranvier and the ring of LaCroix. It is a well defined structure in the growing skeleton. In the adult it is assumed to be integrated with the periosteum however, this has not been well explored in the adult human being."

"Markers associated with and suggested to define possible stem cells or progenitor cells in mesenchymal tissue and also, in some cases, in adult cartilage are CD105(Endoglin), CD166 (Alcam) and FGFR3 (Fibroblast Growth Factor receptor 3)"

ID1 and ID3 are involved in the proliferation of adult articular chondrocytes.

"A significant decrease in DNA synthesis was noticed when antisense nucleotides against Id1 and Id3 were added, both in normal chondrocytes and chondrosarcoma cells."

"Progenitor cells exist in the perichondrial groove of Ranvier and in the articular cartilage of rabbits (IV)"

"The markers associated with stem cells/progenitor cells and stem cell niches: Stro-1, Notch1, Patched, Jagged1, BMPr1a, 1-Integrin and N-cadherin"

"Progenitor cells exist in the knee of sexually mature rabbits and are mainly located to the perichondrial groove of Ranvier. Progenitor cells have also been detected in small numbers dispersed throughout the articular cartilage."

"The groove of Ranvier in the joint is a potential stem cell niche"

Monday, June 24, 2013

Inhibiting growth plate ossification without inhibiting growth

Usually, when the ossification stage of endochondral bone growth is inhibited so is growth like when MMP13 is inhibited for example.  However, in the chicken growth plate, ossification can be inhibited without affecting longitudinal bone growth.  If we apply this to humans, we can have eternally open growth plates.

We do know there are instances in humans where ossification is inhibited but tall stature is achieved by means such as aromatase deficiency.  It's possible that the people with aromatase deficiency could have quincidentally had tall stature or they could have had other mutations in addition to aromatase defiency that makes estrogen less essential to longitudinal bone growth.  Perhaps, these mutations are related to making growth plates more like the chicken growth plate.

Pinealectomy in a broiler chicken model impairs endochondral ossification and induces rapid cancellous bone loss

"Adolescent idiopathic scoliosis (AIS) in humans is a lateral curvature of the spine often associated with osteopenia. It has recently been accepted that the development of AIS is closely associated with spinal overgrowth{a more controlled means of inducing spinal overgrowth with a similar pathology to scoliosis may be a possible height increase technique}. Pinealectomy (PNX) in a chicken model consistently induces scoliosis with anatomic features similar to human AIS.
A histomorphometric study was performed to analyze longitudinal bone growth and cancellous bone remodeling before the development of scoliosis. Static and dynamic parameters in cancellous bone and chondro-osseous junction of the 7th thoracic vertebral body at 9 days after hatching were compared between PNX chickens and control chickens with no surgery.
PNX resulted in a rapid and marked loss of cancellous bone volume (7.9±0.9% vs. 14.2±1.8%) and profoundly disrupted trabecular structure with increases in dynamic formative parameters, such as mineralizing surface, mineralization apposition rate, and adjusted appositional rate. In the chondro-osseous junction, activated osteoclasts phagocytized degenerating chondrocytes, leaving a minimal amount of cartilage matrix and activated osteoblasts, losing their scaffolding for bone formation, and directly covering the hypertrophic zone cells. The osteoid surface and thickness in the chondro-osseous junction were significantly increased in PNX chickens (43.1±14.2% vs. 11.6±5.7% and 4.1±0.2μm vs. 2.9±0.4 μm). In the subjacent cartilage regions being protected from further resorption, abundant labeled cartilage remained with higher cellularity.
Fast-growing birds have a unique paradigm of rapid bone elongation with minimal metaphyseal bone production. A bone-forming surface exists at the front of cartilage ossification in the growth plate; therefore, papillae of hypertrophic chondrocytes become included between the trabeculae of metaphyseal bone and the overall thickness of the growth plate increases considerably in addition to distal expansion. Our results indicate that the unique mechanism for rapid bone elongation in chicken is more pronounced after PNX."

"Supplementation with melatonin, the hormone produced by the pineal gland, in PNX chickens produces less severe spinal deformities"<-but does melatonin also reduce the overgrowth?

"Pinealectomy (PNX) alters growth plate morphologies by enlarging the bone-forming surface.  A bone-forming surface exists in front of the cartilage ossification with intermittent penetration of metaphyseal vessels. Papillae of degenerated hypertrophic chondrocytes extend into the metaphysis with osteoblasts on the surface forming primary bone trabeculae in a direction parallel to bone growth. In PNX chickens, osteoblast coverage at the ossification front is enlarged. Some of the osteoblasts align perpendicular to bone growth. Enlargement of the calcein-labeled hypertrophic zone  and higher numbers of proliferative chondrocytes are seen."

PNX increased the hypertrophic zone area.  Longitudinal bone growth was not labeled in this study however.  But "“The unique paradigm of rapid bone growth”  is more pronounced following PNX, suggesting longitudinal over-growth."

"In the growth plates of mammals, the ossification front is essentially straight because of the simultaneous replacement of hypertrophic chondrocytes by bone in a transverse plane and is solely composed of eroded surface. The majority of longitudinal bone growth results from advancing the whole plate by newly synthesized primary spongiosa, ie, cell proliferation and matrix synthesis at the top of the plate is more or less matched by resorption, thus the thickness of the growth plate stays reasonably constant. In the growth plates of chickens, metaphyseal vessels invade the zone of hypertrophy at intervals and resorption does not occur synchronously across the plate and a bone-forming surface exists in the chondro-osseous junction. Growth plate cartilage becomes included within the newly formed bone and the chondro-osseous junction undulates. A bone-forming surface exists and the subjacent region is temporarily protected from further resorption (protected regions). Primary spongiosa is not produced where endochondral bone is produced in direction perpendicular to longitudinal growth. The increase in thickness of the growth plate with reduced metaphyseal bone production considerably contributes to rapid longitudinal bone growth{can we mimic this in humans?}. Following PNX in chickens, activated osteoclasts and osteoblasts enlarge endochondral bone coverage. The subjacent region is protected from further resorption, resulting in the increase in thickness of the growth plates"

"at 6 days following PNX we found histological changes that were seen after activated osteoclasts and/or chondroclasts to a large extent phagocytized degenerating chondrocytes leaving a minimal amount of cartilage matrix. Activated osteoblasts, losing their scaffolding for bone formation, directly cover the hypertrophic cells. The enlarged endochondral bone coverage further minimizes metaphyseal bone production, leading to a rapid and marked loss of cancellous bone volume, and would accelerate bone elongation economically.  Where endochondral bone covers the cartilage, the subjacent region is temporarily protected from further resorption"<-maybe a surgery can be developed to inject endochondral bone into the growth plate preventing growth plate resorption.

Let's look at the genes produced in the chicken growth plate to see if there are any that could be linked to these protected growth plate regions i.e. eternal growth plate formation without fusion.

Screening of differentially expressed genes in the growth plate of broiler chickens with Tibial Dyschondroplasia by microarray analysis.

"Tibial dyschondroplasia (TD) is a common skeletal disorder in broiler chickens. It is characterized by the presence of a non-vascularized and unmineralized cartilage in the growth plate{so we get an even better idea of genes that might protect from resorption}. Previous studies have investigated differential expression of genes related to cartilage development during latter stages of TD. The aim of our study was to identify differentially expressed genes (DEGs) in the growth plate of broiler chickens, which were associated with early stage TD. We induced TD using tetramethylthiuram disulfide (thiram) for 1, 2, and 6 dayss.
We identified 1630 DEGs, with 82, 1385, and 429 exhibiting at least 2.0-fold changes  at days 1, 2, and 6, respectively. These DEGs participate in a variety of biological processes, including cytokine production, oxidation reduction, and cell surface receptor linked signal transduction on day 1; lipid biosynthesis, regulation of growth, cell cycle, positive and negative gene regulation, transcription and transcription regulation, and anti-apoptosis on day 2; and regulation of cell proliferation, transcription, dephosphorylation, catabolism, proteolysis, and immune responses on day 6. The identified DEGs were associated with the following pathways: neuroactive ligand-receptor interaction on day 1; synthesis and degradation of ketone bodies, terpenoid backbone biosynthesis, ether lipid metabolism, JAK-STAT, GnRH signaling pathway, ubiquitin mediated proteolysis, TGF-β signaling, focal adhesion, and Wnt signaling on day 2; and arachidonic acid metabolism, mitogen-activated protein kinase (MAPK) signaling, JAK-STAT, insulin signaling, and glycolysis on day 6."

"thiram-induced TD is not produced through an increase in chondrocyte multiplication in the transition zone, nor by altering the expression of genes causing the arrest of chondrocytes in a pre-hypertrophic state. It acts by creating metabolic dysfunction that leads to the destruction of blood capillaries in the transition zone chondrocytes. Thiram could promote chondrocyte proliferation in the growth plate of chickens, and disturbs the regulation of endochondral calcification and development of normal cartilage. This results in prehypertrophic cell accumulation, angionecrosis, abnormal extracellular matrix synthesis, deferred endochondral calcification, and bone resorption"

" the expression level of secreted frizzled-related protein 4 (sfrp4) was upregulated 2.8-, 73.5-, and 11.6-fold on days 1, 2, and 6, respectively. The expression level of cadherin 1 (cdh1) was upregulated 31.4- and 10.9-fold on days 2 and 6, respectively. Similarly, expression of enolase 2 (eno2) was upregulated 2.3-, 10.5-, and 4.0-fold on days 1, 2, and 6, respectively."

"lysyl oxidase (lox), which was upregulated, participates in crosslinking of extracellular collagen via oxidative deamination of lysine or hydroxylysine"

"Downregulation of prostaglandin E receptor 4 (subtype EP4) (ptger4) and arginine vasopressin receptor 2 (avpr2) on day 1 directly influenced signal transduction and blood vessel elasticity. On day 2, downregulation of a variety of synthases altered the production of lipid compounds that are precursors of hormones, vitamin D, PTGD, and PTGE, all of which likely have an important role in angiogenesis, regulation of transcription and cell proliferation, and bone development."

Detailed comparison of these genes to LSJL genes to be done.  Unfortunately, I could not find a comparison of normal chicken to human growth plates.

There was a weight loading study that weight loading in young chicks increased bone resorption but decreased longitudinal bone growth.  Maybe weight loading destroys the protected areas of the growth plate.  If this were true, then that study would not be relevant to humans as humans do not have the protected zones of the growth plate.

Does Tybial dyschondroplasia cause overgrowth in chickens?

Changes in the tibial growth plates of chickens with thiram-induced dyschondroplasia.

"Tibial dyschondroplasia (TD) is a metabolic cartilage disease of young poultry in which endochondral bone formation is disrupted leading to the retention of a non-calcified, avascular plug of cartilage in the tibial growth plate. Chicks aged 7 days were fed either a control diet or one containing thiram 100 ppm for 48 h to induce TD. Cell multiplication in the growth plate was determined thereafter with bromodeoxyuridine (BrdU) labelling, and metabolic changes by measuring alkaline phosphatase (ALP), tartrate-resistant acid phosphatase (TRAP), and glutathione (GSH) activities. The effect on chondrocyte maturation was examined. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling (TUNEL) and DNA fragmentation were used to determine the effects of thiram on cell survival.  Thiram-induced TD was not due to the multiplication of cells in the post-proliferative zones. Thiram did not affect ALP activity, which would have indicated a loss of calcification potential, but it reduced both TRAP and the glutathione concentrations, suggesting that the growth plate metabolism and remodelling functions were adversely affected. Thiram appeared to have no effect on the expression of type X collagen, transglutaminase, RUNX2, or matrix metalloproteinase-2 (MMP) genes suggesting that it did not alter the maturation potential of chondrocytes. On the contrary, the expressions of MMP-13 and vascular endothelial growth factor (VEGF) genes were "up-regulated," suggesting that thiram has pro-angiogenic activity. Thiram induced endothelial cell apoptosis in the capillary vessels of the growth plates, as early as 10 days of age, when TD was not visually evident. The vascular death increased on subsequent days accompanied by massive death of chondrocytes in the transition zone of the growth plate. The induction of apoptosis in the growth plate was also demonstrated by DNA fragmentation.  Thiram induced TD not through an increase in the multiplication of chondrocytes in the transition zone and not by altering the expression of genes causing the arrest of chondrocytes in a prehypertrophic state, but by creating a metabolic dysfunction which led to the destruction of blood capillaries in the transition zone chondrocytes."

Thiriam also depleted Guthione levels.

Full-size image (36 K)
"Typical morphology of growth plates from control and thiram-fed chickens aged 16 days. (a) Control growth plate. (b) Growth plate with TD severity score of 1 from a thiram-fed chicken. (c) Growth plate with a severity score of 2 from a thiram-fed chicken."<-C looks overgrown but I can't say for sure.  Tibial dyschondroplasia is associated with rapied chicken growth but we can't say in which way is the causal direction.

However, in instances where there are protected regions of the growth plate inhibiting ossification may increase and induce longitudinal bone growth.  This may be the reason for the deformity as only some areas are protected thus only some areas have overgrowth thus resulting in deformity like in C.

Chondrocytes and longitudinal bone growth: the development of tibial dyschondroplasia.

"Chondrocyte proliferation proceeds normally in TD, but markers of the differentiated phenotype, local growth factors, and the vitamin D receptor are abnormally expressed within the prehypertrophic chondrocytes above, and within, the lesion. Tibial dyschondroplasia is associated with a reduced incidence of apoptosis, suggesting that the lesion contains an accumulation of immature cells that have outlived their normal life span. Immunolocalization studies of matrix components suggest an abnormal distribution within the TD growth plate that is consistent with a failure of the chondrocytes to fully hypertrophy. In addition, the collagen matrix of the TD lesion is highly crosslinked, which may make the formed lesion more impervious to vascular invasion and osteoclastic resorption. "

"Abnormal, nonuniform bone growth within the area of the [TD] lesion leads to increased tibial plateau angle and tibial bowing"<-this deformity may be due to overgrowth.

So if we can recreate regions of the growth plate that can undergo longitudinal bone growth without needing the resorption phase like in some parts of the chicken then we can grow taller forever.

Monday, June 10, 2013

Stannioncalcin 1 & 2: Two targets for inhibition for height growth

 STC1 and especially STC2 are two potent targets for inhibition during development enhancing height growth.  So I open it up to brainstorming to try to find inhibitors.

Stanniocalcin 1 Acts as a Paracrine Regulator of Growth Plate Chondrogenesis

"During embryogenesis, the expression of mammalian stanniocalcin (STC1) in the appendicular skeleton suggests its involvement in the regulation of longitudinal bone growth. Such a role is further supported by the presence of dwarfism in mice overexpressing STC1. Yet, the STC 1 inhibitory effect on growth may be related to both postnatal metabolic abnormalities and prenatal defective bone formation. In our study, we used an organ culture system to evaluate the effects of STC on growth plate chondrogenesis, which is the primary determinant of longitudinal bone growth. Fetal rat metatarsal bones were cultured in the presence of recombinant human STC (rhSTC). After 3 days, rhSTC suppressed metatarsal growth, growth plate chondrocyte proliferation and hypertrophy/differentiation, and extracellular matrix synthesis. In addition, rhSTC increased the number of apoptotic chondrocytes in the growth plate. In cultured chondrocytes, rhSTC increased phosphate uptake, reduced chondrocyte proliferation and matrix synthesis, and induced apoptosis. All these effects were reversed by culturing chondrocytes with rhSTC and phosphonoformic acid, an inhibitor of phosphate transport. The rhSTC-mediated inhibition of metatarsal growth and growth plate chondrocyte proliferation and hypertrophy/differentiation was abolished by culturing metatarsals with rhSTC and phosphonoformic acid.  STC1 inhibits longitudinal bone growth directly at the growth plate. Such growth inhibition, likely mediated by an increased chondrocyte phosphate uptake, results from suppressed chondrocyte proliferation, hypertrophy/differentiation, and matrix synthesis and by increased apoptosis. Last, the expression of both STC1 and its binding site in the growth plate would support an autocrine/paracrine role for this growth factor in the regulation of growth plate chondrogenesis. "

"sodium-dependent Pi (NaPi) transporter(s) may be a target of STC1 activity"

PFA is an additional inhibitor of phosphate transport also used in the study.  STC decreased the hypertrophic or proliferatize zone height to an additional degree than PFA which had a relatively minor decrease.  STC also decreased cartilage matrix synthesis to a much greater degree than PFA.

"100 ng/ml rhSTC significantly increased Pit-1 mRNA expression in the metatarsal growth plate, whereas it decreased mRNA expression of FGF23"<-FGF23 is involved in phosphate homeostasis and increases chondrocyte hypertrophy.

"When compared with control mice, STC transgenic mice exhibited a 30-50% postnatal growth reduction."

"In a study on ADTC5 cells (a chondrogenic cell line), treatment with Pi and Ca2+ led to a decrease in the Bcl-2/Bax ratio, which is believed to disrupt the mitochondrial membrane and promote release of mitochondrial components, irreversibly engaging the cell toward apoptosis"

STC1 overexpression enhances osteoblast differentiation according to Stanniocalcin 1 stimulates osteoblast differentiation in rat calvaria cell cultures.

The murine stanniocalcin 1 gene is not essential for growth and development.

"Stc1 function is not essential for growth or reproduction in the mouse."

STC1 null mice had improved bone density but does that mean increased height?  Weight growth was lower in STC1 null mice but no measurements of longitudinal bone growth were provided but they did say that growth was normal.

STC2 deletion however does increase growth according to The murine stanniocalcin 2 gene is a negative regulator of postnatal growth.

More on STC1 and STC2: Human stanniocalcin-2 exhibits potent growth-suppressive properties in transgenic mice independently of growth hormone and IGFs.

Thursday, May 16, 2013

Growth Plate Regeneration

This is from the Google Preview of the Book Bone: Fracture Repair and Regeneration.  Specifically the chapter: Prospects of Regeneration of Growth Plates in Mammals written in 1992. 

The author Richard M. Libbin is old.  I believe he is still alive in New York but I couldn't find contact info.  The book was available for $8 so I bought it so I'll have more information from it.

Overall the book doesn't have new revolutionary information but it makes several statements that provide evidence for the possibility of height increase by LSJL or other mechanical means.

One interesting theory he presents is that the osseous bridge formed during growth plate fracture decreases height by decreasing blood flow to the growth plate.  Blood flow has been shown to affect growth plate and height growth via genes like HSP90.

The author mentions a regrowth of the hemiephysis occurring in some instances but "physeal regeneration does not occur innately in the distal humerus of the rat."

"Physeal regeneration [sites may be] formed via chondrocyte reorganization within the junctional cartilage."

"Regions of physeal regrowth were observed in the cartilage which had formed distal to the skeletal transection surfaces, and also within the junctional cartilage proximal to them."

"Proliferation of periosteal cartilage similar in morphology to fracture callus is the starting point for physeal regeneration"

"Regeneration of growth plate cartilage does not occur at forelimb amputation sites of rats [because] while exuberant periosteal chondrogenesis rapidly encloses the hindlimb bone ends within a mass of hyaline cartilage, in the forelimb the equivalent process occurs less frequently and less vigrous, newly formed cartilage rarely extending beyond the plane of amputation.  The failure of rat forelimb growth plate cartilage to regenerate may reflect a deficiency in the chondrogenic potential of its periosteum."

On page 274, he mentions an argument that states that regenerative capacity is never completely lost in higher level vertebrates.  In frogs, which can regenerate as tadpoles but not as full frogs the lack regenerative capacity as adults because cells lose the ability to dedifferentiate.  Maybe this relates to genes such as OCT4, Sox2, Klf4, and Myc.  Once dedifferentiation was induced through trauma, regeneration was achieved.  Maybe LSJL can help induce dedifferentiation.  Dedifferentiation may be a key step before neo-growth plates can be formed.

"In [instances of] regrown junctional cartilage, [that cartilage] now contained extended regions of growth plate cytoarchitechture, suggesting that physeal organization is not restricted to the ends of long bones, but may be provoked to occur at other sites as well."

On page 280, it's mentioned that cartilage formed off the periosteum is very similar to the growth plate in terms of cellular organization.

"Any cartilage or cartilage forming tissue may be able to reform a growth plate."<-MSCs and the periosteum is cartilage forming tissue.  The problem with MSCs is the microenvironment of the adult bone.  The goal with LSJL is induce mesenchymal condensation thus allowing MSCs to become cartilage forming tissue.

"Physeal cartilage may be provoked to form anywhere along the length of the bone"

"growth plate cartilage phenotype may be expressed wherever cartilage is present"

"After complete physeal ablation following division of the limb, it is periosteal cartilage which forms the regenerate, the characteristic ordered arrangement of growth plate chondrocytes appearing within an expanse of nonphyseal, hyaline cartilage as had occurred during the development of bone in fetal and neonatal life."

Mention of voluntary muscle at the skeletal end being important to cartilage regrowth.  This is a place of cutoff so when I get the book, I'll analyze it.

Other Chapters:

Synthesis and Stability during Fracture Repair


"[A lack of blood vessals may not lead] to chondrogenesis because some large, sinusoid-like vessels [was detected] in the cartilage of rat tibial fractures."

"[Some] areas of cartilage, or chondroid bone, are transient, persisting for only a few days, and so the proteoglycans may not mature to their normal levels of sulfation."


Regeneration of the growth plate.

"in 5 different series of experiments reported between 1950 and 1986 regeneration of injured parts of growth plates in long bones of rabbits and pigs could be demonstrated. The 1st series implied partial X-ray injury of growth plates in rabbits aged 3–6 weeks.The 2nd series implied autotransplantation of the head of the fibula in rabbits aged 10–21 days. The 3rd, 4th and 5th series implied transplantation of autologous fat grafts into provoked defects of growth plates in rabbits and pigs. The findings show that regeneration of a growth plate occurs when a part of it is injured in such a manner that a bone bridge is not formed between the epiphysis and the metaphysis. Regeneration of a plate is much faster in relation to the growth in length of the bone in the rabbit than in the pig. The 1st and 2nd series suggest that regeneration takes place by interstitial proliferation of cells from the germinal layer of the uninjured parts of the plate. Signs of partial regeneration of growth plates have been seen in radiographs after operation for partial closure of growth plates in children. "

Interesting that fat tissue was implanted to prevent bone fusion.

IGF-I RELEASING PLGA SCAFFOLDS FOR GROWTH PLATE REGENERATION

"rat bone marrow cells (BMCs) [were seeded] on the top of IGF-I encapsulated PLGA scaffolds, and the results showed an increase in cell multiplication and glycosaminoglycan content. "  They were then implanted into injured growth plates.  Of course, the question is what would be the effect of this implantation in a bone with no active growth plate.

"The practical difficulty in the use of IGF-I is due to its short biological half life. Encapsulation of IGF-I with PLGA protects the bioactivity and stability of IGF-I."

"Stacks of chondrocytes were observed in the case of the native growth plate. In the regenerated growth plate the chondrocytes were not found in the usual stacked manner. Single chondrocytes were distributed in the extra cellular matrix in the regenerated growth plate."<-maybe this is due to lack of some chemicals like BMP-2 or Ihh?

Monday, May 13, 2013

Lateral Synovial Joint Loading Supplement Guide

In an earlier post, I estimated that you can gain 1/4" every two months from lateral synovial joint loading.  This seems to be going along with how St.it(He reported gains of about 0.5 cm for 2 months so about 1/5") and RT(gains of about 1 cm in a month and a half) have reported gaining on the LSJL forum.  Now, what LSJL is good at is good at is inducing chondrogenic differentiation which can cause height growth.  But anything anabolic that can accelerate the rate of cellular proliferation can make this height growth occur faster like HGH.

And incorporating LIPUS and electromagnetic fields(which are important as shown by the pizeoeletric current and the OPG/RANKL gradient).

I'm not going to be going into things like supplement purity and supplement forms(yet).  That's something that will come with time.  Note that all supplements and dosages are at your own risk.  I only study the possible effects of supplements on height increase.  All the information I have on the supplements is based on the studies I present on this blog.  This means that there are possible interactions and side effects that I may overlook.  This list is intended to inspire discussion about the possibility of supplements to increase height and to inspire discussion about possible risks and side effects.  I do not vouch for the safety of any supplements nor do I provide any dosages.  If you want vouches of safety than look to the manufacturer or to an organization such as the FDA.

DNA Protectors like Sam-e may not be necessary with a normal diet but as you do more anabolic activities or take more anabolic supplements your need for these supplements may increase.

I'm will be including supplements like Viagra and Lithium that are only available by prescription.  Because if people are aware of the height increasing potential of certain supplements that might increase the availability.

Dosages of each supplement likely vary based on diet, weight, and activity level.

Basic Lateral Joint Loading Routine(Lateral Loading of the Epiphysis):
-Increases cellular differentiation stem cells to chondrocytes which leads to height growth.
-Increases TGF-Beta, Wnt, and ECM pathways(Hyaluronic Acid).

LIPUS:
-Need more TGF-Beta1.  Won't increase height without TGF Beta.
-Increases Aggrecan Expression.
-Inhibits GSK-3Beta increasing cellular proliferation(which is why it makes bone fractures heal faster).

PEMF:
Increases TGF-Beta release.

Axial Loading(Heavy Weightlifting):
-Increases TGF-Beta
-Increases all kinds of anabolic hormones(net gain in cellular proliferation resulting in more need for anti-oxidants and DNA methylaters)
-Increases need for calories

Endurance Training:
-Can increase VO2 max which can lengthen telomeres
-Increases sensitivity to Growth Hormone.

Now the Supplements:

c-Fos inhibitors:

-Apigenin

Beta-Catenin inhibitors:

-Quercetin

EstrogenReceptorAlpha inhibitors:

-Royal Jelly

ECM(Extracellular Matrix) Protectors:

-As your shear strain increases your need for more ECM increases so endurance training, sprinting or other exercises that cause shear strain on chondrocytes.  You'll notice that your bones will crack more after endurance training(not like a chiropractic crack but more of a dry crack).

So the more you run the more of these you'll need-
-Chondroitin & Glucosamine
-Hyaluronic Acid <-More Important than Chondroitin & Glucosamine for growing taller

Seaweed and Beta-Glycerophosphate:
Beta-Glycerophosphate may play a role in allowing endochondral ossification without periosteum.  Seaweed may help increase ECM levels.

Forskolin:
Increases proteoglycan syntehesis and aggrecan mRNA.

Glucosamine may only have benefits if you engage in a lot of joint taxing exercises whereas hyaluronic acid and chondroitin can help you grow taller during puberty or while performing LSJL.

DNA Protectors:


-B6, B12, Folic Acid(<-The need for these increases the more anabolic activities you engage in or the more anabolic supplements intake)

-Folinic Acid may provide additional protection for DNA.  It should also be noted that Folinic Acid produced an observable increase in growth plate morphology and a non-significant increase in longitudinal bone growth.

-Sam-e(<-You only need this if B6, B12, and Folic Acid are not performing their jobs which they do in most people)

-Telomere Length(Astragalus Membranaceous which also doubles as an anti-oxidant)

-Anakrina and Entarnercept(prescription only substances that act to inhibit TNF-alpha and IL-1Beta, those two compounds are produced endogenously by growth plate chondrocytes and reduce growth)

Increase Cellular Proliferation(May not always increase final adult height but results in faster gains in LSJL and doesn't hurt):


-Examples are HGH, Myostatin Inhibitors, IGF-1, Testosterone.  The higher your cellular proliferation rate the more DNA protectors and anti-oxidants you need.  Use all supplements as directed(Niacin must be taken at a specified large dose).  Remember, that anabolic supplements increase non-bone cells as well such as skin cells, muscle cells, etc.  Usually, adipogenic differentiation is inhibited though.

-Creatine(inhibits Myostatin)

-Lactoferrin(increases chondrocyte proliferation, also available in milk)

The below two supplements are testosterone boosters and have a role in the nitric oxide pathway which can increase height growth:

-Tribulus Terristris

-Horny Goat Weed

-Niacin(enhances the bodies response to HGH when taken in large doses)

-Puerarin(increases cellular proliferation by the PI3K pathway)

-Leptin(increases cellular proliferation)

Lithum:
-Increases cellular proliferation and hypertrophy be inhibiting GSK3Beta however may have negative effects on height like stabilizing Beta-Catenin.  However, inactivation of Beta Catenin & overexpression of Sox9 has been shown to reduce height.  Methylation of Sox9 by CARM1 inhibits Beta-Catenin degradation so upregulating Beta-Catenin may not be needed in some circumstances.

Sophorae Beans:
Increases TGF-Beta and IGF-1 levels.

Cnidium:
Increases bFGF, IGF-1, and BMP-2 levels.

Alfalfa(Ipriflavone):
Increases IGF-1 and Type II Collagen levels.

Growth Plate regulation(Endochondral Ossification Pathways):

Teriparatide:
Parathyroid hormone antagonizes Ihh, Runx2, and TypeX Collagen differentiation plus upregulates CyclinD1.  So basically Parathyroid Hormone delays terminal differentiation and increases chondrocyte proliferation.  PTH also stimulates Nkx3.2 which increases type II collagen(cartilage) and GAG production. Parathyroid Hormone is pro-chondrogenic.

Viagra:
PDE5 inhibitor and stimulates the Nitric Oxide pathway.  The Nitric Oxide Pathway and CNP both increase cGMP levels thus like CNP may increase longitudinal growth.  Viagra is a far more effective NO pathway stimulator than something like arginine, as Viagra targets a NO pathway inhibitor(PDE5) and so may be less susceptible to negative feedback mechanisms than something like Arginine.

Ecdysterone:
Stimulates NO pathway.

Harpogoside:
Inhibits NFKappaB which inhibits height growth in active growth plates.  In bones with no growth plates, NF-kappaB may cause apoptosis of bone cells and stimulate stem cells.  So you shouldn't take Harpogoside if you have active growth plates.

Anti-Oxidants:


Vitamin C:
Vitamin is pro-chondrogeneic.  It is unclear whether levels of Vitamin C above requirements would help increase height however Vitamin C deficiency reduces height. Vitafusion Power C, Gummy Vitamins For Adults, 150-Count.

-Pretty much all anti-oxidants are good except for NAC which inhibits free radicals that are essential for height growth(NADPH).

Melatonin:
Increases levels of TGF-Beta in addition to scavenging free radicals.  Note that Melatonin increases levels of CYP1A2 which metabolizes Melatonin.  Therefore it may be necessary to cycle Melatonin.  Also note, that most doses of Melatonin may be too high and may increase CYP1A2 levels higher than a low dose for the same beneficial effects.  Many studies have found 0.3mg of Melatonin to be effective versus the 3mg in most supplement tablets. Here's 0.5mg Melatonin: Pure Encapsulations Melatonin 0.5 mg - 180 capsules.

-Acai Berry has been shown to be a highly effective anti-oxidant and it is available in foods(Acai berry enhanced smoothies)

Diet:

Silicon Reduced Diet:
-Silicon Deficiency may have possibility to inhibit growth plate closure and increase longitudinal growth.
-Silicon seems to be pro-bone rather than pro-cartilage.  Thus, a silicon deficiency may be favorable to increased chondrogenesis.

So if you want to grow taller faster with LSJL.  First, look at what physically can you do that's anabolic like cardio and weight training.  Then make sure as you increase your activity level increase your levels of chondrocyte protectors as necessary.  Also increase your levels of DNA protectors and anti-oxidants.

With each supplement that's anabolic you try up your anabolic and DNA protector supplement content as well.  For safety, whenever possible go for water soluble supplements like Vitamin C.

Thursday, May 2, 2013

Grow taller with Collagen Hydrolysates

Collagen Hydrolysates are available for sale:
Alfa Vitamins Collegen Hydrolysate Nutrition Supplement, 120 Count

This makes it a very promising supplement but the cost of the dosage ratios recommended would be insane but could be up to 25% additional height.  There are 120 pills for $10.  A 50lb kid would take 25 a day to meet the dosage requirements.  So that would be about $2.50 a day.  Which I guess is not that bad.

Porcine Skin Gelatin Hydrolysate Promotes Longitudinal Bone Growth in Adolescent Rats.

"Collagen hydrolysates (CHs) are mixtures of peptides obtained by partial hydrolysis of gelatin that are receiving scientific attention as potential oral supplements for the restoration of osteoarticular tissues. The aim of this study was to evaluate the effectiveness of CHs for promoting longitudinal bone growth in growing rats. An in vitro study was carried out in osteoblast-like MG63 cells and the most effective CH on bone formation was selected among 36 various CHs. An in vivo study confirmed the functional effects of a selected CH with molecular weight of <3 kDa on longitudinal bone growth. CHs dose-dependently promoted the longitudinal bone growth and height of the growth plate in adolescent male rats, whereas gelatin failed to affect longitudinal bone growth. Insulin-like growth factor-1 and bone morphogenetic protein-2 in the CH treated group were highly expressed in the growth plate."

"Collagen is the major constituent of the connective tissues in vertebrates, comprising 30% of total body protein. The denatured form of collagen is referred to as gelatin and is commonly used in foods, pharmaceuticals, cosmetics, and others. To increase the solubility of gelatin, partially hydrolyzed gelatin products have been prepared and are referred to as collagen hydrolysates (CHs)."

3-Week old male Sprague-Dawley rats were used.

"Longitudinal bone growth in normal adolescent male rats was 404.0±11.6 μm/day, and administration of 50 and 250 mg/kg gelatin failed to promote the longitudinal bone growth. However, treatment with 250 mg/kg of CH significantly increased the longitudinal bone growth exhibiting 468.4±27.4 μm/day."<-The dosage for the alfa vitamins collagen above is 1000mg.  So maybe a human should actually take a larger dosage.  250mg/kg is actually pretty insane dosage in terms of cost but growth was over 25% more. That's 550mg/lb.  So a 200lbs individual would have to take 100 pills a day.  50mg/kg still increased height just not statistically significantly.

Here's the growth plate under Collagen Hydrolysate(growth plate height was increased by 11%).
http://online.liebertpub.com/na101/home/literatum/publisher/mal/journals/content/jmf/0/jmf.ahead-of-print/jmf.2012.2461/20130430/images/large/figure3.jpeg
"CHs with molecular weights <3000 Da that is able to increase IGF-1 and BMP-2 protein expression in growth plate, and consequently promote longitudinal bone growth in growing rats."<-the molecular weight of the supplement above is not listed.  Looking it up Collagen Hydrolysate has an average molecular weight of 2000-5000 Da so it's possible that the molecular weight here is over the threshold but humans may be able to tolerate the higher moleculate rate than rats.

Food consumption doesn't seem to be measured but gelatin could serve as sort of a control to that.

The osteochondral endplate

The osteochondral endplate is the place where the articular cartilage meets the bone.  What we've learned about plastic deformation is that is a threshold strain that must be achieved to induce longitudinal growth in the bone.  Studies with epiphyseal distraction have shown that stretching the growth plate rarely increases height without fracturing the bone.

Directly stretching the growth plate did not increase height unless there was fracture or the distraction caused an increase in growth plate activity.  Since stretching the growth plate region does not directly increase height it is unlikely that the growth plate region increases height by stretching that region.  If growth plate increased height by stretching the bone shouldn't a mechanism of stretching like epiphyseal distraction also increase height?


We also know that the amount of tensile strain to induce a longitudinal stretch in the cortical bone is extreme and unlikely to be generated by the growth.  The growth plates must induce a physical mechanism of growing taller, otherwise cartilage would just transform into bone and your bones would not grow longer.  I propose that this method involves a force against the osteochondral endplate.


The epiphysis is weaker than the diaphysis of the bone.  The epiphysis is not cylindrical shaped so it is less stable.  This is a picture of the tibia:



What if the mechanism of growing taller was just to push away the osteochondral endplate and then the stronger cortical bone grows around it?

The Cartilage-Bone Interface

"Mature articular cartilage is integrated with subchondral bone through a 20 to 250 μmthick layer of calcified cartilage. Inside the calcified cartilage layer, perpendicular chondrocyte-derived collagen type II fibers become structurally cemented to collagen type I osteoid deposited by osteoblasts. The mature mineralization front is delineated by a thin 5 μm undulating tidemark structure that forms at the base of articular cartilage.  Growth plate cartilage is anchored to epiphyseal bone, sometimes via a thin layer of calcified cartilage and tidemark{so the tidemark that is at the same at the osteochondral endplate is similar to that of growth plate cartilage}, while the hypertrophic edge does not form a tidemark and undergoes continual vascular invasion and endochondral ossification (EO) until skeletal maturity upon which the growth plates are fully resorbed and replaced by bone.  The tidemark can be regenerated through a bone marrow-driven growth process of EO near the articular surface."

"In the developing knee, epiphyseal bone will continue to expand into the cartilage anlage until the cartilage interface forms a thin calcified layer that arrests vascular invasion.  Calcified cartilage forms at the base of the articular cartilage, and in certain growth plate reserve zones"

"Growth plate hypertrophic cartilage (HTC) does not form a tidemark. This interface is actually a mixture of cartilage and bone, by definition of the primary spongiosa,where newbone is deposited on the cartilage trabeculae carved out by invading blood vessels and marrow"

"Like articular cartilage, the growth plate hypertrophic zone also contains collagen type X and alkaline phosphatase, but a tidemark is notably absent. The tidemark that forms at the base of mature articular cartilage develops slightly below the region of chondrocytes expressing collagen type X.  Mineral deposits form in the neonatal calcified layer of the articular cartilage in line with the collagen fibers."




According to this diagram the articular cartilage grows by appositional growth so you should be able to grow taller with no growth plates by appositional growth in the articular cartilage.

"The calcified cartilage layer is semipermeable and permits passage of small molecules (<500 Da) from the subchondral bone to the articular cartilage layer"

"Thickening of the calcified cartilage in OA could be expected to reduce the flow of small solutes from the vascularized subchondral bone to the deep zone chondrocytes."<-Maybe this could be part of the reason that people with osteoarthritis don't grow taller?

"Once formed, the tidemark and calcified cartilage layer persist as dynamic structures that can change and remodel over time. Below mature articular cartilage, the mineralization front is a relatively smooth and undulating plate-like surface"<-Maybe this remodeling of the tidemark and calcified cartilage layer plays a role in height growth

"growth plates develop a relatively stable reserve zone-epiphyseal bone interface, with a purely collagen type II GAG-rich cartilage phase, and a mixture of collagen type I and collagen type II in the newly forming primary spongiosa. Calcified cartilage becomes established at the edges of a “permanent” epiphyseal bone layer (i.e., proximal reserve zone and articular cartilage hypertrophic zone), and the tidemark serves as a barrier to vascular invasion and calcification of hyaline cartilage."<-maybe we can induce tidemarks to prevent growth plate resorption.

"The mineral front at the base of the growth plate corresponds with the vascular bone and newly deposited collagen type I. In the growth plate hypertrophic zone, calcification of the collagen type II matrix is much delayed compared with the articular cartilage calcified layer. This is because after
birth, the mammalian joints require a suitable mechanically stable articular surface, while growth plates in the long bones are continually expanding, even beyond sexual maturity. Cartilage calcification is therefore only occurring at the end-stage of cartilage growth. After reaching skeletal maturity, growth plates are completely resorbed and replaced by collagen type I–positive mineralized bone."<-So it's possible that the tidemark is both the limiting factor for the articular cartilage and the growth plate.

"Calcified cartilage becomes established at the edges of a “permanent” epiphyseal bone layer (i.e.,
proximal reserve zone and articular cartilage hypertrophic zone), and the tidemark serves as a barrier to vascular invasion and calcification of hyaline cartilage."<-So if you cause advancement of the tidemark you may create a signal for the bone to grow longer.

"In the calcified cartilage layer of normal human femoral condyles, chondrocytes are quiescent[not dividing] and present at a much lower density compared with hyaline cartilage (average of 51 cells/mm2 versus 152 cells/mm2).The calcified cartilage layer is flanked by an undulating tidemark, and an even more irregular cement line adjacent to the bone"

"the ratio of calcified cartilage to total cartilage thickness [is] relatively constant."  Calcified cartilage layer thins with age and older adults can experience tidemark advancement.

"The tidemark is a 5 μm thick structure that appears at the cartilage-calcified cartilage junction"

"A significant correlation was observed between increasing tidemark duplication, mineral density, and carbonate content in primates. Repetitive knee microtrauma in a rabbit model during 9 weeks of loading was shown to lead to a mean 25% increase in the proximal tibial calcified cartilage layer thickness, and tidemark duplication, with no change in mean articular cartilage thickness"

"chondrogenic foci will spontaneously form in drill or microfracture holes generated in skeletally mature knee cartilage defects"

"In some rabbit cartilage repair models involving complete debridement[removal] of the calcified cartilage layer, subchondral bone plate advancement beyond the native tidemark in flanking cartilage has been observed after 3 to 9 months of repair."<-so it may be the calcified cartilage layer that allows for height growth and not the tidemark

"the calcified layer is undergoing continual resorption and endochondral advancement over time"

"the epiphyseal blood vasculature in skeletally immature knees has active endothelial cell proliferation while adult vasculature has postmitotic endothelia and the subchondral bone no longer contains osteoclasts."<-Can LSJL induce endothelial cell proliferation and osteoclast differentiation in adult epiphysis?

I've always said there is nothing that inhibits the formation of growth plates in adult epiphysis.  This study presents two factors that could inhibit adult growth plate formation: lack of proliferating epithelia and no osteoclasts.

According to Early growth response 2 negatively modulates osteoclast differentiation through upregulation of Id helix-loop-helix proteins., egr2(which LSJL upregulates) downregulates osteoclasts by transactivating Id2 however LSJL downregulates Id2.

"All cartilage-bone interfaces develop from an initially cartilaginous structure that undergoes coordinated invasion by blood vessels and osteoblasts. Formation of a tidemark anatomically stabilizes the cartilage-bone interface and arrests cartilage calcification and blood vessel invasion.  Vascularization of the calcified cartilage layer and subchondral bone plate is an important feature of a healthy cartilage-bone interface."

"Calcified cartilage and osteoid in the adult subchondral bone have a similar mineral level."

"Bone plate advancement could be a consequence of delayed or failed tidemark regeneration during bone marrow-driven EO below hyaline-like repair tissue."


"The growth plate-epiphyseal bone interface sometimes includes a layer of calcified cartilage and a tidemark in the reserve zone (A, proximal trochlea), and in other areas is devoid of calcified cartilage
or tidemark and fused to a more vascular bone (B, distal trochlea). Representative decalcified transverse sections from 4-month-old rabbit trochlear growth plates stained with hematoxylin and eosin are shown, from N ¼ 7 distinct New Zealand white rabbit femurs, 4 months old. TM, tidemark (white arrows); BV, blood vessels; CC, calcified cartilage; EO, endochondral ossification (cartilage remnant)."<-Growth for New Zealand White Rabbits really starts to taper off at 19 weeks of age.

Here's the study related to the advancement of the subchondral bone past the tidemark:

Observations of subchondral plate advancement during osteochondral repair: a histomorphometric and mechanical study in the rabbit femoral condyle.

"Osteochondral defects, 3mm diameter by 3mm deep, were made by controlled drilling through the articular surface into the subchondral bone in femoral condyles of 33 rabbits. The repair response was examined at 8, 16 and 32 weeks post surgery.
At 8 weeks, the level of reparative subchondral bone was 0.79+/-0.36 mm below the native tidemark. By 16 weeks, reformed subchondral plate was irregular, showing that 76.5% of the plate had extended beyond the native tidemark (0.13+/-0.05 mm) whilst 16.9% of the plate remained below (0.19+/-0.15 mm). The repaired surface non-osseous layer became thinner than the adjacent cartilage (0.23+/-0.08 vs 0.38+/-0.11 mm, P<0.05). This persisted up to 32 weeks. The repaired surface layers showed disappearance of safranin-O staining, increased separation splits at the boundary, and eventual degradation. General histological scores were similar across 8, 16 and 32 weeks although the scores of defect filling and restoration of osteochondral junction were decreased from 8 to 16 weeks. Mechanically, repaired defects had lower contact pressure and greater indentation than the normal controls at all time. Indentations of the cartilage adjacent to the defects were also greater than the normal at 8 and 32 weeks."



The bone here is taller!  If this had occurred in all the longitudinal ends of the bone you would have a longer bone.  The arrow is pointing to the subchondral bone advancement.

"In [some osteochondral] defects, new marrow-derived cartilage underwent endochondral ossification, forming bone on the surface of calcified cartilage cores. In the depths of the defects, new bone formed directly from osteoblasts derived from marrow mesenchymal cells. The new bone is initially woven, eventually becoming lamella, with the subchondral region modified to form a compact bone plate and a reformed tidemark. However, histological architecture of the reconstituted bone plate and cancellous bone was not identical to the original, and the new tidemark and subchondral bone advanced beyond the native level."

"contact pressure [is the] pressure between the articular surface and the flat circular surface of the transducer."

"contact pressures of reparative articular surfaces were either higher or lower than normal controls, and suggested these differences were related to thickness variation of repaired surface tissue and the presence or absence of an abnormally thick subchondral plate."

There isn't a tidemark for the hypertrophic chondrocytes of the epiphyseal growth plate.  What if the tidemark serves as both the limiting factor for both the articular cartilage and longitudinal bone growth?  With removal of the tidemark/calcified cartilage layer there was advancement of the subchondral bone.  Thus, maybe the growth plate exerts a force causing an advancement of the tidemark allowing for new longitudinal bone growth.

In this model, growth plates would produce upward force(contact pressure) pushing the tidemark upwards allowing for new bone growth.