Effect of growth differentiation factor 11 on the steatosis of condylar chondrocytes in temporomandibular joint osteoarthritic mice.

OBJECTIVES:To observe the effect of growth differentiation factor 11 (GDF11) on the steatosis of condylar chondrocytes in temporomandibular joint (TMJ) osteoarthritic mice. METHODS:Six-week-old female C57 mice were stimulated with unilateral anterior crossbite (UAC) and locally injected with GDF11. TMJ sections were stained with safranin O, and GDF11 and Adiponectin in the TMJ cartilage were detected by immunohistochemical staining. GDF11, Adiponectin, type Ⅱ collagen (Col-Ⅱ), Aggrecan, type Ⅰ collagen (Col-Ⅰ), fatty acid-binding protein 4 (FABP4), and Perilipin 1 mRNA were detected by real-time polymerase chain reaction (real-time PCR). RESULTS:The thickness and safranin O-positive area of TMJ cartilage in the UAC groups, as well as the mRNA expression of Col-Ⅱ and aggrecan, significantly decreased. The ratio of Adiponectin-positive cells significantly increased. The mRNA expression levels of Col-Ⅰ, Adiponectin, FABP4, and Perilipin 1 significantly increased. The TMJ cartilage of the GDF11 injection groups significantly thickened, and the safranin O-positive area significantly increased. The mRNA expression of Col-Ⅱ and Aggrecan significantly increased. The ratio of Adiponectin-positive cells significantly decreased. The mRNA expression levels of Col-I, Adiponectin, FABP4, and Perilipin 1 significantly decreased. CONCLUSIONS:Extensive steatosis of chondrocytes and decreased expression of GDF11 in the degenerated cartilage of TMJ osteoarthritis are induced by UAC stimulation. Supplementation of exogenous GDF11 can effectively inhibit the steatosis of chondrocytes.