Effect And Mechanism Of Electroacupuncture On Energy Metabolism Remodeling Of Cochlear Nucleus In Guinea Pigs With Acute Posterior Circulation Ischemia

Objective:To explore the effects of acute posterior circulation ischemia（PCI）on energy metabolism and SIRT1-PINK1-mediated mitochondrial autophagy in cochlear nucleus of guinea pigs,and the effect and mechanism of electroacupuncture on energy metabolism remodeling of cochlear nucleus in guinea pigs with acute PCI.Methods:1.Animal groups.40 healthy variegated guinea pigs aged 3months old were randomly divided into four groups,including operation group（OG,n=10）,control group（CG,n=10）,electroacupuncture and operation group（EOG,n=10）and sham operation group（SOG,n=10）.The right common carotid artery was surgically dissected and the right subclavian artery was ligated in the guinea pigs of OG.In the EOG,electroacupuncturing at Baihui and Neiguan points was performed for 30minutes every day,and lasted for 7 days after the artery operation as well as OG.Moreover,the carotid exposure was the same as OG,and was not dissected and ligated in SOG.The guinea pigs were natural feeding in CG.2.The uptake value of 18F-FDG in the left and right cochlear nucleus was detected by Micro PET/CT,and the average ratio of SUVmax _left/rightwas analyzed in the cochlear nucleus.3.ELISA was used to detect the ATP level of the right cochlear nucleus in all groups.4.The real-time quantitative PCR was used to detect the expression of PINK1,SIRT1 and LC3 m RNA in the right cochlear nucleus.5.Statistical methods.One-way ANOVA was used for statistics.LSD method was used for comparison between groups when the variance was homogeneous,and tamhane’s T2 test was used when the variance was heterogeneous.The data of each group are expressed as mean±standard deviation（x±s）.The difference is considered to be statistically significant as P<0.05.Results:1.Changes in the glucose metabolism of the cochlear nucleus.The average ratio of SUVmax _left/right was statistically different in the 4groups（F=18.757,P=0.000）.Compared with the CG,the average ratio of SUVmax _left/right increased in the EOG（P=0.002）and OG（P=0.000）,and there was no significant difference in the SOG（P=0.228）.Moreover,the average ratio of SUVmax _left/right in EOG（P=0.028）and OG（P=0.000）increased in comparison with the SOG.Compared with the OG,the average ratio decreased in EOG（P=0.002）.2.ATP Level changes in right cochlear nucleus.There were significantly different in ATP levels of the right cochlear nucleus in 4 groups（F=369.129,P=0.000）.Compared with the CG,the ATP level of the right cochlear nucleus decreased in the OG（P=0.000）,SOG（P=0.000）and EOG（P=0.000）.Furthermore,the ATP levels of the right cochlear nucleus decreased in the OG（P=0.000）and EOG（P=0.000）in comparison with the SOG.Additionally,the ATP level increased in the cochlear nucleus of the EOG（P=0.000,compared with OG）.3.Changes of PINK1,SIRT1 and LC3 m RNA expression in cochlear nucleus.There was no significant difference in the expression of PINK1 m RNA（F=1.192,P=0.327）and LC3 m RNA（F=0.762,P=0.523）in the cochlear nucleus among the 4 groups.However,there was significant changes in the relative expression of SIRT1 m RNA in the cochlear nucleus among the 4 groups（F=3.374,P=0.029）.First,the expression of SIRT1 m RNA was increased in the OG（respectively P=0.004 and 0.049,compared with CG and SOG）.Second,the expression of SIRT1 m RNA was lower in the EOG than that in the OG（P=0.033）.Third,there was no significant difference in the expression of SIRT1m RNA in the EOG（respectively P=0.406 and 0.856,compared with the CG and SOG）.Finally,there was no significant difference in the expression of SIRT1m RNA between the CG and SOG（P=0.313）.Conclusion:1.Glucose metabolism and ATP decreased in the cochlear nucleus of guinea pigs with acute PCI.2.SIRT1 may be involved in the remodeling of energy metabolism of cochlear nucleus in guinea pigs with acute PCI.3.Electroacupuncturing at Baihui and Neiguan points may improve the glucose metabolism and ATP level.4.Electroacupuncturing at Baihui and Neiguan points may participate in the remodeling of energy metabolism of cochlear nucleus in guinea pigs with acute PCI by regulating the expression of SIRT1.5.There are further studies to be performed for the role of Sirt1-Pink1-mediated mitochondrial autophagy in the remodeling of energy metabolism in cochlear nucleus of guinea pigs with acute PCI.