Study On The Inhibitory Effect Of NBP On Autophagy And Its Mechanism In Vascular Dementia Model Rats

Objective:Rapamycin is a specific inhibitor of mTOR.We used the rapamycin and the butylphthalide to interfere rhe VD rats.To investigate the changes of butylphthalide on autophagy on vascular dementia and the effect of beclin-1,LC3 I,LC3II;whether p-mTOR regulates autophagy and vascular dementia in ginseng;effect of butylphthalide on autophagy through mTOR signaling pathway regulation through the methods of Western,blot,HE staining and Nissl staining.Methods:A total of 32 SD rats were randomly divided into four groups,they are sham operation group,VD group,NBP group,and NBP + rapamycin group(N+R group),8 rats in each group.The VD rat model was made by bilateral common carotid artery ligation.The rats in the NBP group and the NBP + rapamycin group were given NBP Capsules for 4 weeks by 60mg/kg by gavage.Rapamycin were given through the lateral ventricle.The sham operation group and the VD rats group were injected with the same dose of normal saline each time,and the same dosage was given for 4 weeks.Rats kept for 4 weeks and the hippocampal tissues was taken though operation.The expression levels of mTOR,p-mTOR,beclin-1 and LC3 II/ LC3 I were detected by HE staining,Nissl staining and Western blot.Results: 1.HE staining showed that the nerve cells in the hippocampal CA1 area of the sham operation group were arranged regularly,the structure and morphology were normal,and the nuclei were large and full.In other groups,the number of neurons decreased,and the structure was disorder.There were different degrees of nuclear condensation and dissolution.Interstitial cells were loose,some cytoplasm was autolysis,vacuoles and vacuoles began to decrease.2.Nissl’s staining showed sham hippocampal neuron morphology,neatly arranged,abundant cytoplasm,large and round cells,Nissl bodies in the cytoplasm stained more content;reduce,other each group of neurons in the hippocampus pyramidal cells are arranged in disorder,morphological changes,cell body shrinkage or swelling,deformation,nuclear pyknosis,cell degeneration,karyopyknosis,nucleolus dissolved,Nissl body reduced number of the degree of change in VD group was the most serious.sham operation group rats showed a large amount of mTOR and p-mTOR positive expression;compared with the sham group,the other 3 CA1 region of the hippocampus of mTOR rats and the expression of p-mTOR decreased,the difference was statistically significant(P < 0.05);compared with VD group,NBP group and N+R group.The expression of p-mTOR and mTOR increased in the NBP group,significant difference was statistically significant(P < 0.05).(2)sham operation group rats showed a positive expression of beclin-1;compared with the sham group,the other 3 groups CA1 of rat hippocampus beclin-1 expression increased,the difference was statistically significant(P < 0.05);compared with VD group,NBP group and N+R group,the positive expression of beclin-1 decreased in the NBP group significant difference was statistically significant(P < 0.05).(3)surgery group rats showed a small amount of LC3-II positive expression;compared with the sham group,the other in hippocampal CA1 region of LC3-II in the 3 groups of rats and increase the expression of LC3II/LC3 I,the difference was statistically significant(P < 0.05);compared with VD group,NBP group and N+R group LC3-II and LC3II/LC3 I expression decreased,which NBP group,significant difference was statistically significant(P < 0.05).Conclusion: 1.Excessive activation of autophagy can be induced in the VD rat model.2,p-mTOR signaling pathway participates in the regulation of autophagy in rat vascular dementia.3,the neuroprotective effect of butylphthalide on vascular dementia is related to autophagy.It plays a neuroprotective role mainly by increasing the expression of mTOR and p-mTOR and decreasing the excessive autophagy induced by vascular dementia.