Objective:To investigate the effect of aucubin(AU)on mitochondrial autophagy in the hippocampus of ischemic stroke(IS)rats by regulating the pten-induced kinase protein 1(PINK1)/cytoplasmic E3-ubiquitin ligase(Parkin)signaling pathway.Methods:The IS rat model was established by middle cerebral artery occlusion(MCAO),and was randomly divided into IS group,low-dose AU group(AU-L),medium-dose AU group(AU-M),high-dose AU group(AU-H),and high-dose AU combined with 3-MA group(AU-H+3-MA).The rats without liga-tion were used as the Sham surgery group.Zea Longa score was used to evaluate the neurological function of rats.TTC staining was used to detect the percentage of cerebral infarction volume.The microstructures of mitochondria were observed by transmission electron microscopy,and the changes of autophagy protein-microtubule associated protein light chain 3B(LC3B)and p62 were detected by immunohistochemistry.Hippocampal apoptosis was detected by TUNEL.PINK1/Parkin-related protein expression in hippocampus was detected by Western blot.Results:Neurological function score of IS rats was increased(P＜0.05),cerebral infarction was observed by TTC staining,the expression of mito-chondrial autophagy protein p62 in hippocampus was up-regulated(P＜0.05),the expression of LC3B was down-regu-lated(P＜0.05),the number of autophagosomes was decreased(P＜0.05),and apoptosis in hippocampus was in-creased(P＜0.05),the expression of PINK1 and ARKIN protein in hippocampus was down-regulated(P＜0.05).After AU intervention,the neural function score of rats was decreased,the percentage of cerebral infarction volume was reduced,the positive expression of p62 in hippocampus was down-regulated(P＜0.05),the positive expression of LC3B was up-regulated(P＜0.05),and the number of autophagosomes was increased(P＜0.05),the apoptosis of hippocampus was decreased(P＜0.05),and the expression of PINK1 and ARKIN protein in hippocampus was in-creased(P＜0.05).3-MA blocked the therapeutic effect of AU and aggravated the nerve injury in rats.Conclusion:AU promotes hippocampal mitochondrial autophagy and improves neurological damage in IS rats by activating the PINK1/Parkin signaling pathway.

Objective:To investigate the effect of aucubin(AU)on mitochondrial autophagy in the hippocampus of ischemic stroke(IS)rats by regulating the pten-induced kinase protein 1(PINK1)/cytoplasmic E3-ubiquitin ligase(Parkin)signaling pathway.Methods:The IS rat model was established by middle cerebral artery occlusion(MCAO),and was randomly divided into IS group,low-dose AU group(AU-L),medium-dose AU group(AU-M),high-dose AU group(AU-H),and high-dose AU combined with 3-MA group(AU-H+3-MA).The rats without liga-tion were used as the Sham surgery group.Zea Longa score was used to evaluate the neurological function of rats.TTC staining was used to detect the percentage of cerebral infarction volume.The microstructures of mitochondria were observed by transmission electron microscopy,and the changes of autophagy protein-microtubule associated protein light chain 3B(LC3B)and p62 were detected by immunohistochemistry.Hippocampal apoptosis was detected by TUNEL.PINK1/Parkin-related protein expression in hippocampus was detected by Western blot.Results:Neurological function score of IS rats was increased(P＜0.05),cerebral infarction was observed by TTC staining,the expression of mito-chondrial autophagy protein p62 in hippocampus was up-regulated(P＜0.05),the expression of LC3B was down-regu-lated(P＜0.05),the number of autophagosomes was decreased(P＜0.05),and apoptosis in hippocampus was in-creased(P＜0.05),the expression of PINK1 and ARKIN protein in hippocampus was down-regulated(P＜0.05).After AU intervention,the neural function score of rats was decreased,the percentage of cerebral infarction volume was reduced,the positive expression of p62 in hippocampus was down-regulated(P＜0.05),the positive expression of LC3B was up-regulated(P＜0.05),and the number of autophagosomes was increased(P＜0.05),the apoptosis of hippocampus was decreased(P＜0.05),and the expression of PINK1 and ARKIN protein in hippocampus was in-creased(P＜0.05).3-MA blocked the therapeutic effect of AU and aggravated the nerve injury in rats.Conclusion:AU promotes hippocampal mitochondrial autophagy and improves neurological damage in IS rats by activating the PINK1/Parkin signaling pathway.