Recent Advances in Animal Models, Diagnosis, and Treatment of Temporomandibular Joint Osteoarthritis.

Temporomandibular joint osteoarthritis (TMJOA) is a gradual degenerative jaw joint condition. Until recent years, TMJOA is still relatively unrecognized and ineffective to be treated. Appropriate animal models with reliable detection methods can help researchers understand the pathophysiology of TMJOA and find therapeutic options. In this study, we summarized common animal models of TMJOA created by chemical, surgical, mechanical, and genetical approaches. The relevant pathological symptoms and induction mechanisms were outlined. In addition, different pathological indicators, furthermore, emerging therapeutic regimens, such as intra-articular drug delivery and tissue engineering-based approaches to treat TMJOA based on these animal models, were summarized and updated. Understanding the physiology and pathogenesis of the TMJOA, together using various ways to diagnose the TMJOA, were elaborated, including imaging techniques, molecular techniques for detecting inflammatory cytokines, histochemical staining, and histomorphometry measures. A more reliable diagnosis will enable the development of new prevention and more effective treatment strategies and thereby improve the quality of life of TMJOA patients. Impact statement Temporomandibular joint osteoarthritis (TMJOA) affects 8 to 16 percent of the population worldwide. However, TMJOA is still relatively unrecognized and ineffective to be treated in the clinic. Appropriate animal models with reliable diagnostic methods can help researchers understand the pathophysiology of TMJOA and find therapeutic options. We herein summarized common animal models of TMJOA and various ways to diagnose the TMJOA. More importantly, emerging therapeutic regimens to treat TMJOA based on these animal models were summarized. With the aid of strategies listed, more effective treatment strategies will be developed and thereby improve the life quality of TMJOA patients.

Heteroexpression of the wheat phytochelatin synthase gene (TaPCS1) in rice enhances cadmium sensitivity.

Phytochelatin synthase (PCS) (EC 2.3.2.15) catalyzes the final step of phytochelatins (PCs) biosynthesis. PCs are a family of cysteine-rich thiol-reactive and heavy metal-binding peptides that play an important role in sequestration and detoxification of heavy metals in plants. Previous studies have indicated that plants that overexpressed PCS displayed contrasting phenotypes, ranging from enhanced cadmium (Cd) tolerance to Cd hypersensitivity in Arabidopsis thaliana. In this study, the wheat phytochelatin synthase gene, TaPCS1, was heteroexpressed in wild-type rice (Oryza sativa L., cv. Zhonghua 11) to evaluate the relationship between synthesis of PCs and Cd tolerance in rice. Data showed that the heteroexpression of TaPCS1 in rice enhanced Cd sensitivity and significantly increased Cd accumulation in shoots, but not in roots. Additionally, the PCS line exhibited a much higher content of PCs and non-protein thiols (NPTs) in shoots. Prominent changes in NPT composition led to reduced glutathione pool depletion and higher Cd content in cell organelles in shoots, followed by higher oxidative stress, which might result in Cd sensitivity. Therefore, the heteroexpression of TaPCS1 in rice is capable of increasing Cd accumulation in rice shoots and enhancing Cd sensitivity.