Salvianolic Acid B Inhibits High‐Fat Diet‐Induced Inflammation by Activating the Nrf2 Pathway

Salvianolic acid B (Sal B) is a major water‐soluble bioactive component of Salvia miltiorrhiza, which is a traditional Chinese medicine. We investigated the ways in which Sal B affects high‐fat diet (HFD)‐induced immunological function disorder remission using a C57BL/6 mouse model. We gave groups of C57BL/6 mice a normal diet (Control), a normal diet supplemented with Sal B (Control + Sal B), a high‐fat diet (HF), and a high‐fat diet supplemented with Sal B (HF + Sal B) for 10 wk. Sal B supplementation decreased the body weight and plasma lipids, increased the fecal excretion of lipids, prevented the accumulation of chronic oxidative stress, and reversed the disproportionality of CD3⁺CD4⁺ and CD3⁺CD8⁺ T lymphocytes compared to HFD. We found an increase in IL‐6 and TNF‐α, while IL‐10 decreased in plasma after the HFD and Sal B reversed the deregulation of the Thl/Th2 ratio. In addition, HFD‐induced inflammation was stopped by Sal B through the downregulation of nuclear factor‐κB (NF‐κB), cyclooxygenase‐2 (COX‐2), and inducible NO synthesis (iNOS), and the upregulation of nuclear factor‐erythroid 2‐related factor 2 (Nrf2)‐regulated genes. These findings demonstrated that Sal B could effectively attenuate inflammation by activating the Nrf2‐mediated antioxidant defense system.