Functional Benefits of Low-Molecular-Weight Collagen Peptide in Achilles Tendon and Medial Collateral Ligament Injuries and Anterior Cruciate Ligament Transection-Induced Osteoarthritis

Musculoskeletal disorders, such as Achilles tendinopathy and anterior cruciate ligament (ACL) injury, can cause serious impairments in physical function and daily life. In particular, ACL rupture increases the risk of osteoarthritis (OA). Collagen maintains the mechanical strength and resilience of tendons and articular cartilage, while low-molecular-weight collagen peptides (LMWCP) support tissue integrity and joint mobility. This study evaluated the efficacy of LMWCP in promoting the repair of Achilles tendon (AT) and medial collateral ligament (MCL), and preventing ACL transection (ACLT)-induced OA. In animal models, LMWCP was administered following AT and MCL injuries, as well as ACLT. LMWCP treatment in the ACLT rabbit model significantly improved cartilage integrity, reducing surface damage, proteoglycan loss, and OARSI scores. It also inhibited subchondral bone deterioration and osteophyte formation, restoring bone volume fraction, as shown by Micro-CT analysis. Moreover, LMWCP administration increased type II collagen expression while decreasing that of matrix metalloproteinases (MMPs) in cartilage tissue, and decreased inflammatory cytokine concentrations in the synovial fluid. In IL-1β-stimulated human chondrocytes, LMWCP suppressed inflammatory cytokines and MMP expression, and increased hydroxyproline content, indicating reduced collagen degradation. In the AT and MCL defect model, LMWCP promoted tissue regeneration by improving fiber arrangement, rounding of nuclei, angiogenesis, and cell density and promoting collagen deposition. These findings suggest that LMWCP may enhance joint function and tendon healing through modulation of inflammation and collagen remodeling, representing a functional ingredient for promoting tendon and ligament repair and attenuating ACLT-induced OA progression.