Effect of picroside H on mitochondria cytochrome C expression and its significance in rats after ischemia/reperfusion / 中华神经医学杂志

ABSTRACT

Objective To investigate the effect ofpicroside Ⅱ on mitochondria cytochrome C (CytC) expression and its significance in rats after ischemia/reperfusion.Methods Ninety-six Wistar rats were randomly divided into sham-operated group,model group,picroside Ⅱ group,Cyclosporin A (CsA,specific antgonist of CytC) group,CsA+picroside Ⅱ group,atractyloside (Atr,selective agonist of CytC) group,Atr+picroside Ⅱ group and DMSO group (n=12);the middle cerebral artery occlusion/reperfusion models referring to Longa's method with medications were adopted,which were established by inserting a monofilament suture into the internal carotid artery for 2 h and then reperfusion for 24 h.After 24 h of ischemia/reperfusion,modified neurological severity scale (mNSS) scores were observed,contents of reactive oxygen species (ROS) in brain tissues were measured by enzyme-linked immunosorbent assay (ELISA),morphology of brain tissues was observed by hematoxylin-eosin staining,ultrastructures ofmitochondria were observed by transmission electron microscopy,apoptotic cells were counted by terminal deoxynucleotidyl transferase dUTP nick end labeling assay (TUNEL),and CytC expression was determined by immunohistochemical assay and Western blotting.Results As compared with the sham-operated group,the model group had significantly increased mNSS scores,ROS contents,number ofapoptotic cells and CytC expression (P＜0.05),and the mitochondria structure was seriously destroyed.The picroside Ⅱ group had obviously decreased mNSS scores,ROS contents,number of apoptotic cells and CytC expression,and the morphology of brain tissue was improved and the mitochondria damage was reduced as compared with the model group,with significant differences (P＜0.05).The Atr+picroside Ⅱ group had significantly decreased mNSS scores,ROS contents,number of apoptotic cells and CytC expression (P＜0.05),and the mitochondria damage in the Atr+picroside Ⅱ group was reduced as compared with that in the Atr group with significant difference (P＜0.05).Conclusion The mechanism of picroside Ⅱ protecting against focal cerebral ischemia reperfusion might attribute to decrease of ROS contents,protection of mitochondria structure and down-regulation of CytC expression in middle cerebral artery occlusion/reperfusion rats.