Mechanical and Glucose Stimulation of Bovine Chondrocytes Affect ECM Synthesis

Loss of articular cartilage is a cause of human morbidity which can potentially be cured with exogenous cartilage replacements. Although more research is required to create functional cartilage inserts, mechanical stimulation of chondrocytes (cartilage cells) in the correct media formulation may improve extracellular matrix (ECM) production, leading to a better-quality cartilage insert. This study aimed to identify the effect of unconfined dynamic compression of bovine chondrocytes seeded in agarose constructs on ECM production in different initial media glucose concentrations. Unstimulated constructs did not produce significantly different amounts of collagen or glycosaminoglycan (GAG) in response to different media glucose concentrations. Also, stimulated construct ECM production did not significantly differ from control constructs in each glucose concentration investigated. However, stimulated constructs in 10 mM glucose produced more collagen and GAG than in media containing 25 mM glucose. Analysis of the yield of lactate on glucose (YL/G) showed that stimulated constructs underwent more aerobic respiration as the glucose media concentration increased, which did not occur for control constructs. Culturing chondrocytes in media containing 10 mM glucose lead to more ECM production than media containing 25 mM glucose and should be used in future stimulation studies.