Therapeutic Effects of Mesenchymal Stem Cells Derived from Bone Marrow and Adipose Tissue in a Rat Model of Temporomandibular Osteoarthritis.

Abstract

Objectives: To examine the potential of intra-articular administration of mesenchymal stem cells (MSCs) derived from bone marrow or adipose tissue to mitigate synovial inflammation in a rat model of temporomandibular joint (TMJ) osteoarthritis (OA).

Methods: In this experimental study, 40 rats were divided into 4 groups: (1) Control group; (2) Untreated TMJ-OA group; (3) TMJ-OA group treated with bone marrow-derived MSCs; (4) TMJ-OA group treated with adipose tissue-derived MSCs. The TMJ-OA model was established by inducing synovial inflammation through the intra-articular administration of complete Freund's adjuvant (CFA). After 8 weeks of TMJ-OA establishment, the animals were sacrificed and each mandibular condyle was extracted for histological evaluation.

Results: The untreated TMJ-OA group had significantly higher synovial inflammation, as indicated microscopically by higher grades of synovial membrane hyperplasia and adhesion, vascular vasodilation, and fibrin deposition than the control group (p < 0.001). Both TMJ-OA groups treated with MSCs had lower grades of synovial inflammation and less severe synovitis than the untreated TMJ-OA group (p < 0.001). The TMJ-OA group treated with adipose tissue-derived MSCs showed lower grades of synovial membrane hyperplasia and higher grades of fibrin deposition than the that treated with bone marrow-derived MSCs (p < 0.001). Other indicators of synovial inflammation and synovitis severity were comparable between the two treatment groups.

Conclusions: Administration of CFA to the TMJ-OA rat model augmented synovial inflammation. Intra-articular administration of MSCs derived from either bone marrow or adipose tissue attenuated the microscopic manifestations of this inflammation, indicating the therapeutic potential of this treatment for TMJ-OA.