He Qi, Li Zhenyu, Wang Yueting, Hou Yanghao, Li Lingyu, Zhao Jing
Department of Pathophysiology, Chongqing Medical University, Chongqing, People's Republic of China; Institute of Neuroscience, Chongqing Medical University, Chongqing, People's Republic of China.
Department of Pathology, Chongqing Medical University, Chongqing, People's Republic of China; Institute of Neuroscience, Chongqing Medical University, Chongqing, People's Republic of China.
Int Immunopharmacol. 2017 Sep;50:208-215. doi: 10.1016/j.intimp.2017.06.029. Epub 2017 Jul 3.
Resveratrol has been reported to protect against cerebral ischemia/reperfusion (I/R) injury in rats, but the underlying mechanism is unclear. In the current study, we examined whether resveratrol ameliorates cerebral I/R injury by inhibiting NLRP3 inflammasome-derived inflammation and whether autophagy is involved in this process. In addition, we explored the role of Sirt1 in resveratrol-mediated protective effects. To answer these questions, healthy male Sprague-Dawley rats were exposed to middle cerebral artery occlusion for 1h followed by 24h reperfusion. We found that cerebral I/R increased levels of activated NLRP3 inflammasome, caspase-1, IL-1β, and IL-18 and enhanced autophagy activity (ratio of LC3B-II/LC3B-I and p62/SQSTM1). Treatment with resveratrol, a specific Sirt1 agonist, attenuated I/R-induced NLRP3 inflammasome-derived inflammation but upregulated autophagy. Furthermore, resveratrol treatment clearly reduced cerebral infarct volume, decreased brain water content, and improved neurological scores. In addition, inhibition of autophagy using 3-MA intracerebroventricular injection blocked the inhibitory effect of resveratrol on NLRP3 inflammasome activation. Finally, Sirt1 knockdown with siRNA significantly blocked resveratrol-induced enhancement of autophagy activity and suppression of NLRP3 inflammasome activation. In conclusion, our results demonstrate that resveratrol protects against cerebral I/R injury by inhibiting NLRP3 inflammasome activation through Sirt1-dependent autophagy activity.
据报道,白藜芦醇可保护大鼠免受脑缺血/再灌注(I/R)损伤,但其潜在机制尚不清楚。在本研究中,我们研究了白藜芦醇是否通过抑制NLRP3炎性小体衍生的炎症来改善脑I/R损伤,以及自噬是否参与了这一过程。此外,我们还探讨了Sirt1在白藜芦醇介导的保护作用中的作用。为了回答这些问题,将健康雄性Sprague-Dawley大鼠暴露于大脑中动脉闭塞1小时,然后再灌注24小时。我们发现,脑I/R增加了活化的NLRP3炎性小体、半胱天冬酶-1、白细胞介素-1β和白细胞介素-18的水平,并增强了自噬活性(LC3B-II/LC3B-I和p62/SQSTM1的比率)。用特异性Sirt1激动剂白藜芦醇治疗可减轻I/R诱导的NLRP3炎性小体衍生的炎症,但上调自噬。此外,白藜芦醇治疗明显减少了脑梗死体积,降低了脑含水量,并改善了神经学评分。此外,通过脑室内注射3-MA抑制自噬可阻断白藜芦醇对NLRP3炎性小体激活的抑制作用。最后,用siRNA敲低Sirt1可显著阻断白藜芦醇诱导的自噬活性增强和NLRP3炎性小体激活的抑制。总之,我们的结果表明,白藜芦醇通过依赖Sirt1的自噬活性抑制NLRP3炎性小体激活,从而保护免受脑I/R损伤。