Effects of chrysophanol on hippocampal damage and mitochondrial autophagy in mice with cerebral ischemia reperfusion

Objective The cerebral ischemia-reperfusion (I/R) model is crucial for the study of cerebral stroke. Chrysophanol (Chry) can protect nerve damage of mice in cerebral ischemia-reperfusion injury. This study aimed at investigating the neuroprotective effects of chrysophanol through mitochondrial autophagy in mice with ischemia-reperfusion injury. Materials and methods Adult mice were stochastically divided into five groups: sham, I/R (solvent), I/R+Chry (dose, 10.0ml/kg), I/R+Chry (dose, 1.0ml/kg), and I/R+Chry (dose, 0.1ml/kg). The cerebral ischemia-reperfusion model was made in I/R and I/R+Chry groups. The changes in hippocampal formation were observed by hematoxylin and eosin (H&E) staining. The expressions of LC3B-II and LC3B-I protein in hippocampus were demonstrated by western blot (WB). The fluorescence intensities of NIX, LC3B, and mitochondria were detected by immunohistochemistry fluorescent (IF). Results Comparing with the I/R group, the I/R+Chry groups showed improvements in reducing the damage on the hippocampus, indicated by the reduced ratio of LC3B-II and LC3B-I protein, decreased fluorescence intensity of NIX and LC3B, and increased intensity of mitochondrial fluorescence. Conclusion Our study showed that chrysophanol may regulate mitochondrial autophagy through NIX protein and alleviate the damage of hippocampus through decreasing the level of mitochondrial autophagy.