CAT and rheumatoid arthritis: For example, it was observed that TQ led to the upregulation of antioxidant enzymes such as catalase (CAT), glutathione peroxidase, and superoxide dismutase (SOD), enhancing effects on oxidative stress, leading to hepatoprotective effect, blocked Nuclear factor erythroid 2-related factor 2 (Nrf2)/Heme oxygenase-1 (HO-1) pathway, which led to the protection of epithelial cells from oxidative stress and effects on rheumatoid arthritis in experimental models.