Curcumin alleviates lung injury in diabetic rats by inhibiting nuclear factor-κB pathway

Summary Curcumin is a polyphenolic compound that is extracted from Curcuma longa. It has broad anti-inflammation and anti-tumor activities. Curcumin was previously reported to exert beneficial effects on diabetes. However, the effect of curcumin on diabetes-induced lung injury is not yet clear. In this study, the effects of curcumin on lung injury induced by diabetes was explored using quantitative real time polymerase chain reaction (PCR), enzyme-linked immunosorbent assay (ELISA), immunohistochemistry and electrophoretic mobility shift assay. The results of this study showed that curcumin reduced oxidative stress level, inhibited the synthesis of nitric oxide and prostaglandin E2, and reduced inflammatory responses in the lungs of diabetic rats, thereby alleviating diabetes-induced lung injury. Further study of the mechanism revealed that curcumin inhibited the activation of nuclear factor (NF)-κB which is a key player in inflammatory responses. In summary, our study demonstrated that curcumin inhibited the activation of NF-κB in the lungs of diabetic rats, thus reducing pulmonary inflammatory responses and oxidative stress, and ultimately relieving diabetes-induced lung injury. This study suggests that curcumin may be a promising agent to alleviate diabetic lung injury and also provides theoretical foundation for the development of diabetes therapy.