Static and dynamic compression modulate matrix metabolism in tissue engineered cartilage

Static and dynamic compression are known to modulate the metabolism of articular cartilage. The present study focussed on determining the effect of compressive loading on the metabolism of sulfated glycosaminoglycans (S-GAG) and protein in tissue engineered cartilage constructs. Cartilage constructs were subjected to static or dynamic compression for 24 h and radiolabeled with (SO4)-S-35 and H-3-proline to assess the total synthesis and percentage retention of S-GAG and total protein, respectively. Static compression at an amplitude of 50 suppressed the synthesis of both S-GAG and protein by 35% and 57%, respectively. Dynamic compression at an amplitude of 5% had stimualtory effects on synthesis that were dependent on the static offset compression amplitude (10% or 50%) and dynamic compression frequency (0.001 or 0.1 Hz). Thus, tissue engineered cartilage demonstrated the ability to respond to mechanical loading in a manner similar to that observed with articular cartilage. Mechanical loading may therefore potentially be used to modulate the growth of cartilaginous tissues in vitro, potentially facilitating the culture of functional cartilage tissues suitable for implantation. (C) 2002 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.