The Effects Of Ginsenoside Rg1 On Inhibiting Cortical Protein And Aggregation Inflammatory Response Underlying Mechanism After Cerebral Ischemia And Reperfusion Injury In Rats

Objective:To observe the effect of Rgl(Ginsenoside Rgl)on cerebral infraction volume,neurological score,protein aggregation and inflammation in a cerebral ischemia/reperfusion(I/R)injury model,and investigate the underlying mechanism of neuroprotection of Rg]Methods:72 male SD rats were divided into sham operation group,I/R model group,the ginsenoside Rgl treatment group(10 mg/kg,20 mg/kg,40mg/kg)and the nimodipine positive drug control group.Each group includes 12 rats.The sham group didn't perform the occlusion,and the rest groups occluded the middle cerebral artery using the thread embolizing in rats.After 90 minutes ischemia followed by 24 h reperfusion.the cerebral ischemia/reperfusion models were established.Rgl treatment group(10 mg/kg,20 mg/kg,40mg/kg)and the nimodipine positive drug control group were given by intraperitoneal injection,while the sham operation group and I/R model group were injected with saline by intraperitoneal injection.The neural function score of each group was measured 24 hours after ischemia reperfusion after model building,respectively.The expression of protein aggregates,proteasomes,NF-?B and I-?B?were detected by Western blotting and lmmunohistochemistry.The activity of proteasome was detected by fluorometric peptidase assay.Pro-inflammatory cytokines were measured using ELISAResults:Compared to the I/R model group,treatment with GS Rgl 40 mg/kg demonstrated a significantly reduced infarct volume and improved the neurological deficit as well as the histological appearance(P<0.()5).In addition,GS Rgl treatment significantly reduced the secretion of proinflammatory cytokines and suppressed the nuclear translocation of NF-?B as well as the phosphorylation of I?B?(P<0.01).Finally,Ginsenoside Rgl down-regulates proteasome activity and inhibits the protein aggregate accumulation in the brain.(P<0.01)Conclusions:1.GS Rgl can protect neurons and reduce the volume of cerebral infarction:2.GS Rgl can improve the neurological damage after cerebral ische mia/reperfusion and promote the recovery of neurological function;3.GS Rgl can inhibit the protein aggregate accumulation,reduce the expression of proteasome,and down-regulate the activity of proteasome;4.GS Rgl can ameliorate nerve cell injury,improve its tolerance to reperfusion injury and have a neuroprotective effect.In conclusion,GS Rgl can effectively inhibit cortical protein aggregation and neuroinflammation after ischemia/reperfusion,but the underlying mechanism needs to be further studied.