Extended mechanical stimulations of cartilage for growth and repair

Abstract

Extended mechanical stimulation of articular cartilage in an in vitro model explant system promotes growth and repair. An alternating day mechanical loading protocol consisting of dynamic sinusoidal compression results in long term extracelluar matrix macromolecule biosynthesis and increased biosynthetic rates in the cartilage system. The protocol uses total glycosaminoglycan and DNA content assays to measure matrix macromolecule biosynthesis and uses L-³H-proline and ³⁵S-sulfate radiolabel incorporation rates to measure rates of biosynthesis. The results also demonstrate the feasibility of replacing the fetal bovine serum and L-ascorbic acid components of the typical explant feeding medium with ITS (insulin-transferrin-selenium solution) and acorbyl-2-phosphate in anticipation of future long term studies of the synergistic pathways of dynamic compression and IGF-I stimulation for cartilage growth and repair.