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.

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

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"

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.