Increase Height with Hyaline Cartilage

Scientists have shown that it is possible to recreate a growth plate within hyaline cartilage using a mesenchymal chondrocarsonoma. Since we know that growth plate fusion doesn't inhibit height growth, we can try to recreate a new cartilagenous growth plate within the epiphyseal fusion.

In vivo restoration of full-thickness cartilage defects by poly(lactide-co-glycolide) sponges filled with fibrin gel, bone marrow mesenchymal stem cells and DNA complexes. 

"A composite construct comprising of bone marrow mesenchymal stem cells (BMSCs), plasmid DNA encoding transforming growth factor-beta1 (pDNA-TGF-beta1), fibrin gel and poly (lactide-co-glycolide) (PLGA) sponge was designed and employed. To improve the gene transfection efficiency, a cationized chitosan derivative N,N,N-trimethyl chitosan chloride (TMC) was employed as the vector. The TMC/DNA complexes had a transfection efficiency of 9% to BMSCs and showed heterogeneous TGF-beta1 expression in a 10-day culture period in vitro. In vivo culture of the composite constructs was performed by implantation into full-thickness cartilage defects of New Zealand white rabbit joints, using the constructs absence of pDNA-TGF-beta1 or BMSCs as controls. Heterogeneous expression of TGF-beta1 in vivo was detected at 4 weeks, but its level was decreased in comparison with that of 2 weeks. After implantation for 12 weeks, the cartilage defects were successfully repaired by the composite constructs of the experimental group, and the neo-cartilage integrated well with its surrounding tissue and subchondral bone. Immunohistochemical and glycosaminoglycans (GAGs) staining confirmed the similar amount and distribution of collagen type II and GAGs in the regenerated cartilage as that of hyaline cartilage. The cartilage special genes expressed in the neo-tissue were closer to those of the normal cartilage. An overall score of 2.83 was obtained according to Wakitani's standard. By contrast, only part of the defects was repaired by the pDNA-TGF-beta1 absence constructs, and no cartilage repair but fibrous tissue was found for the BMSCs absence constructs. Therefore, combination of the PLGA sponge/fibrin gel scaffold with BMSCs and gene therapy is an effective method to restore cartilage defects." 

Well if you want to create a new growth plate this is the way to do it.  For height increase, it's preferable to use the existing hyaline cartilage but inserting new hyaline cartilage and sending bone marrow mesenchymal stem cells(with appropriate genetic expression) can have applications like fixing scoliosis. 

Recombinant human midkine stimulates proliferation of articular chondrocytes.

"Midkine, a heparin-binding growth factor, promotes population growth, survival and migration of several cell types.
Bromodeoxyuridine incorporation and MTT assays were performed to examine the proliferative effect of recombinant human midkine (rhMK) on primary articular chondrocytes. Activation of extracellular signal-regulated kinase (ERK) and phosphatidylinositol 3-kinase (PI3K) was analysed using western blot analysis. Systemic and local delivery of rhMK into mice and rats was preformed to investigate the proliferative effect of rhMK in vivo, respectively. Histological evaluation, including measurement of articular cartilage thickness, cell density, matrix staining and immunostaining of proliferating cell nuclear antigen was carried out. rhMK promoted proliferation of articular chondrocytes cultured in a monolayer, which was mediated by activation of ERK and PI3K. The proliferative role of rhMK was not coupled to dedifferentiation of culture-expanded cells. Consistent with its action in vitro, rhMK stimulated proliferation of articular chondrocytes in vivo when it was administered subcutaneously and intra-articularly in mice and rats, respectively. rhMK stimulates proliferation of primary articular chondrocytes in vitro and in vivo." 

If you have actively proliferating chondrocytes(either by your natural growth or via delivering stem cells to the hyaline cartilage growth plate) and inject the growth factor rhMK then you will grow taller.  More proliferating chondrocytes equals more chondrocytes dying and eventually being invaded by bone cells thus resulting in longer bones. 
Hyaline cartilage is the base for which long bones grow.  Stem cells differentiate into chondrocytes under orders from TGF-beta.  You inject hyaline cartilage into new areas and activate endochondral ossification then you get new growth possibilities.

Here's a patent involving using Midkine for hair growth.  Maybe there's a way to apply it to growth plate chondrocytes.

"MK is known to promote the migration of inflammatory cells such as macrophages and neutrophil, leading to inflammation."

"Pleiotrophin (PTN or HB-GAM) is a midkine family protein having approximately 50% identity at the amino acid sequence level to MK. Both MK and PTN comprise a high content of cysteine and basic residues. All the 10 cysteine residues are conserved in MK and PTN, and structurally, both can be divided into the N-domain and the C- domain. As a result of NMR analysis, it is known that these two molecules have very similar three-dimensional structures. Each domain consists of three β sheets, connected via a flexible linker region. K79, R81 , and K102, considered to be important to the binding of to chondroitin sulfate and heparin, are conserved between the two proteins[So pleiotrophin does bind to chondrogenic factors]. MK and PTN also share three-dimensional structures wherein these basic residues appear in the vicinity of the protein surface. Accordingly, PTN has been disclosed previously for the same medical indications as MK."

There doesn't appear to be an oral form of MK and PTN at this time.


Chondromodulin I and pleiotrophin gene expression in bovine cartilage and epiphysis.

"Pleiotrophin and chondromodulin-I are low molecular weight proteins that are abundant (20 microg/g tissue) in fetal cartilage and difficult to detect in adult cartilage. The results showed that the mRNAs for both proteins were abundant in fetal cartilage and while present in adult cartilage, were at 20-60-fold lower levels. Northern blotting revealed gradients of mRNA for both of these proteins in growth plate cartilage, with the highest levels in the resting zone, and the lowest in the hypertrophic zone. In contrast to pleiotrophin, chondromodulin-1 is down-regulated by retinoic acid with a pattern of expression similar to collagen type II and link protein, and may play a more specific role than pleiotrophin in modulating the chondrocyte phenotype."

"Ptn is upregulated by platelet-derived growth factor"

Grow Taller with Hyaline Cartilage?

Since Hyaline Cartilage is the type of cartilage within the resting zone of the growth plate, it is a very important type of cartilage to know about.  The resting zone of the growth plate is where the stem cells are located which we want to increase proliferation of with Lithium or IGF-1.  Although mesenchymal stem cells do have the ability to generate new cartilage from nowhere(and thereby a new growth plate) it would be useful to know whether the growth plate line consists of hyaline cartilage.  It doesn't make sense for the layer of hyaline cartilage to ever go away because the other layers undergo apoptosis and are eventually replaced by bone.  Hyaline cartilage does seem to ossify but it occurs after the rest of the apoptosis.  Hyaline cartilage seems to be the extracellular matrix product of chondrocytes.  You can increase the serum level of the bone marrow of various extracellular matrix components like by supplementation of Hyaluronic Acid.

Reappraisal of mesenchymal chondrosarcoma: novel morphologic observations of the hyaline cartilage and endochondral ossification and beta-catenin, Sox9, and osteocalcin immunostaining of 22 cases. 

"Mesenchymal chondrosarcoma, a rare malignant round cell and hyaline cartilage tumor, is most commonly intraosseous but can occur in extraskeletal sites. We intensively observed the morphology and applied Sox9 (master regulator of chondrogenesis), beta-catenin (involved in bone formation, thought to inhibit chondrogenesis in a Sox9-dependent manner), and osteocalcin (a marker for osteoblastic phenotype) to 22 central nervous system and musculoskeletal mesenchymal chondrosarcoma. Immunohistochemistry and follow-up were obtained on mesenchymal chondrosarcoma and tumor controls. Twenty-two mesenchymal chondrosarcomas included 5 central nervous system (all female; mean age, 30.2; mean size, 7.8 cm; in frontal lobe [n = 4] and spinal cord [n = 1]) and 17 musculoskeletal (female-male ratio, 11:6; mean age, 31.1; mean size, 6.2 cm; 3 each of humerus and vertebrae; 2 each of pelvis, rib, tibia, neck soft tissue; one each of femur, unspecified bone, and elbow soft tissue). The hyaline cartilage in most tumors revealed a consistent linear progression of chondrocyte morphology, from resting to proliferating to hypertrophic chondrocytes[What does this sound like?  Yup.  The growth plate.]. Sixty-seven percent of cases demonstrated cell death and acquired osteoblastic phenotype, cells positive for osteocalcin at the site of endochondral ossification. Small round cells of mesenchymal chondrosarcoma were negative for osteocalcin. SOX9 was positive in both components of 21 of 22 cases of mesenchymal chondrosarcoma. beta-Catenin highlighted rare nuclei at the interface between round cells and hyaline cartilage in 35% cases. Control skull and central nervous system cases were compared, including chondrosarcomas and small cell osteosarcoma, the latter positive for osteocalcin in small cells. Mesenchymal chondrosarcoma demonstrates centrally located hyaline cartilage with a linear progression of chondrocytes from resting to proliferative to hypertrophic, which undergoes endochondral ossification, recapitulating growth plate cartilage and suggesting that this component of mesenchymal chondrosarcoma may be a differentiated (benign or metaplastic) component of a malignant metastasizing tumor. This hyaline cartilage component is morphologically different from cartilage of control chondrosarcoma. Mesenchymal chondrosarcoma can be separated from small cell osteosarcoma, using Sox 9 for cartilage and osteocalcin for osteoblastic phenotype. Rare nuclear beta-catenin expression at the interface between hyaline cartilage and small round cells potentially implicates the APC/Wnt pathway during endochondral ossification in morphologically benign hyaline cartilage component of mesenchymal chondrosarcoma." 

This mesenchymal stem cancer cell was able to replicate the growth plate in almost any hyaline cartilage layer(given the presence of Sox9 and beta-catenin).  67% of the hyaline cartilage layers were able to finish the job and turn into bone.  Sox9 helps provide nutrients to the chondrocytes and unless Sox9 becomes absent the chondrocytes won't die and turn into bone. 

"Histologically, mesenchymal chondrosarcoma has a characteristic biphasic pattern composed of a cellular poorly differentiated small round blue cell component interspersed with islands of well-differentiated hyaline cartilage."

"The hyaline cartilage in most mesenchymal chondrosarcomas showed apparent linear progression of chondrocytes from primitive “resting” chondrocytes to proliferating chondrocytes and then hypertrophic chondrocytes, which underwent visible cell death and endochondral bone formation, recapitulating normal growth plate cartilage"

Histology of chandrosarcoma. "Mesenchymal chondrosarcoma is biphasic with small round cell and centrally located hyaline cartilage components (A-C) and bone formation (A-D; see arrow, A). Bone formation is central but located in the top portion of B. The hyaline cartilage in mesenchymal chondrosarcoma is morphologically benign as it often appears to progress in a zonal pattern from small resting, chondrocytes to proliferating, then hypertrophic chondrocytes that die and become replaced by bone, via endochondral ossification. The interface between the cartilage and bone has chondrocyte swelling then linear chondrocyte cell death (D, arrows) and replacement of cartilage template by bone, recapitulating long bone growth plate."

"Sox9 is not specific to chondrocytes and can be found in Sertoli cells and can generate insulin-producing β-cells from stem cells in the pancreas"

How does cartilage grow?

A cartilage growth mixture model with collagen remodeling: validation protocols.

"New stress constitutive equations for the solid matrix are derived and collagen (COL) remodeling is incorporated into the CGM model by allowing the intrinsic COL material constants to evolve during growth. An analytical validation protocol based on experimental data from a recent in vitro growth study is developed. Available data included measurements of tissue volume, biochemical composition, and tensile modulus for bovine calf articular cartilage (AC) explants harvested at three depths and incubated for 13 days in 20% fetal borine serum (FBS) and 20% FBS+beta-aminopropionitrile. The proposed CGM model can match tissue biochemical content and volume exactly while predicting theoretical values of tensile moduli that do not significantly differ from experimental values. Also, theoretical values of a scalar COL remodeling factor are positively correlated with COL cross-link content, and mass growth functions are positively correlated with cell density. The results suggest that the CGM model may help us to guide in vitro growth protocols for AC tissue via the a priori prediction of geometric and biomechanical properties."

"The extracellular solid matrix (SM) of AC contains proteoglycans (PGs) and a crosslinked collagen (COL) network"<-this is true of growth plate cartilage as well.

"The PGs are aggregate molecules containing glycosaminoglycans (GAGs) that provide the tissue with a fixed charge density (FCD) that causes a swelling pressure that resists compressive loading"<-the hydrostatic pressure in the AC increases in response to compressive loading.  The growth plate cartilage is constantly compressed by two parts of bone so it has a high hydrostatic pressure there.  Bone does not have these GAGs so it does not have the manipulate fixed charge density to alter hydrostatic pressure.  Therefore it makes sense for bone to generate GAGs(and the chondrocytes to create them) in response to dynamic loading and hydrostatic pressure.

"The crosslinked COL network resists the PG swelling pressure and provides the tissue with both tensile and shear stiffnesses and strengths"

Bioengineering cartilage growth, maturation, and form.

"The growth of cartilage may arise nonuniformly in distinct regions of the tissue through specific biologic activities of the indwelling cells termed chondrocytes[so stem cells that differentiate into chondrocytes could grow cartilage growth plates]. These cells are embedded in a highly hydrated extracellular matrix consisting predominantly of collagen type II and aggrecan, a large, negatively charged proteoglycan. Growth may be mediated through increases in either the cell volume fraction by proliferation or hypertrophy or in the matrix volume fraction by a net accretion of constituent molecules. Early in cartilage development, the tissue is highly cellular, so significant changes in cell number or volume would likely have proportional effects on the tissue volume. As sources of matrix secretion, chondrocytes at high density would also be well poised to contribute to growth through their anabolic production of matrix molecules. However at later stages of growth, chondrocyte density is reduced , and the capacity for further growth is diminished[so proliferative capacity may be related to chondrocyte density, keep chondrocyte density high and keep growing taller]."

In the study, they recommend IGF-1 and BMP-7 as a way to increase cartilage size.