| Similar to other musculoskeletal tissues, tendons have the ability to adjust their constituents and structural design in response to changes in their mechanical environment, a phenomenon called remodeling . However, the cell-based mechanisms of load-associated remodeling are not well-understood. An organ culture in vitro model was developed and used to investigate the load-associated remodeling of tendons. Tendons were cultured in the absence of load (Unloaded group) or under low static load (Static group) for one week. We investigated remodeling at the organ, matrix and cell levels by evaluating mechanical (elastic and viscoelastic) properties, extracellular matrix composition and gene expression. In relation to control (Fresh group), the results showed that load deprivation decreased the elastic properties while a low static load increased the elastic properties and also changed the viscoelastic properties for both cultured groups. In terms of matrix composition, hyaluronan decreased in both cultured groups while chondroitin/dermatan sulfate glycosaminoglycan increased only in the Static group. There were no changes in collagen, water content in either cultured group and both cultured groups showed similar changes in gene expression pattern. Our results suggest that proteoglycans and other factors not evaluated, but not collagen, may be involved in the load-associated remodeling process at one week. Also, changes in gene expression seemed to be have been related to the culture environment and not to specific changes in mechanical load. |
