High-Fructose Diet Aggravates Temporomandibular Joint Cartilage Degeneration

Temporomandibular joint (TMJ) is the only bilateral joint of craniomaxillofacial region, and temporomandibular joint osteoarthritis (TMJOA) is a common disease in TMJ. The damaged cartilage homeostasis is one of the fundamental causes of TMJ cartilage degeneration, and it is related to the abnormal metabolism of cartilage, which may come from the accumulation of metabolites of cells or the change of diet. Fructose diet is a common dietary habit; in this study, the relationship between fructose diet and TMJ cartilage degeneration was investigated through the establishment of preclinical models and histological examination. The results showed that at least in the short term, fructose diet alone could not lead to significant TMJ cartilage morphological abnormalities, but fructose diet could lead to more serious lesions in the degenerated condylar cartilage, including more obvious and severe cartilage degradation and more apoptotic chondrocytes. Molecular biology also showed that the catabolism of condylar cartilage matrix significantly increased, and anabolism significantly decreased after fructose drinking water, with TMJ cartilage tissue degeneration. The mechanism behind this histological phenotype may be related to the combined effect of fructose in coordination with IL-1β on condylar chondrocytes. The results of this study showed that fructose drinking water can aggravate the damage to condylar cartilage tissue homeostasis, thus aggravating the condylar cartilage degeneration of TMJ, suggesting that a high-fructose diet may be avoided in order to protect the cartilage homeostasis after condylar cartilage injury clinically.