Effects of electroacupuncture on mitophagy in hippocampal neurons of mouse depression model
10.3969/j.issn.1006-2157.2025.09.016
- VernacularTitle:电针对抑郁模型小鼠海马神经元线粒体自噬的影响
- Author:
Zhiyun YU
1
;
Wenmiao YANG
;
Mingmin XU
;
Zhiyan LI
;
Chenchen YANG
;
Junhan JIANG
;
Yinan FENG
;
Yu GUO
Author Information
1. 暨南大学中医学院 广州 510632;暨南大学中医学院广州市中医方证重点实验室
- Publication Type:Journal Article
- Keywords:
depression;
electroacupuncture;
hippocampal neurons;
mitophagy;
phosphatase and tensin homolog-induced kinase 1/Parkin pathway;
mice
- From:
Journal of Beijing University of Traditional Chinese Medicine
2025;48(9):1310-1323
- CountryChina
- Language:Chinese
-
Abstract:
Objective To explore the therapeutic effect and mechanism of electroacupuncture on depressive model mice based on the phosphatase and tensin homolog-induced kinase 1(PINK1)/Parkin pathway.Methods Specific pathogen-free grade male C57BL/6J mice were used.For experiment 1,60 mice were randomly divided into blank,model,sham electroacupuncture,and electroacupuncture groups using the random number table method,with 15 rats per group.For experiment 2,30 mice were randomly divided into normal,cyclosporine A(CsA),and electroacupuncture+CsA groups using the same method,with 10 rats per group.The chronic restraint stress(CRS)was used to establish a depression model.After successful modeling,CRS was continued to maintain model stability.After modeling,1 h before daily CRS stimulation,the electroacupuncture and electroacupuncture+CsA groups received electroacupuncture interventions at the"Baihui"(GV20)and"Zusanli"(ST36)acupoints,using continuous wave stimulation at a frequency of 2 Hz and an intensity of 1 mA for 20 min,once daily for 7 consecutive days.Mice in the sham electroacupuncture group received superficial needling at non-meridian,non-acupoint locations under the axilla 1 h before CRS,with the electroacupuncture device connected but not powered on once a day for 7 consecutive days.Mice in the CsA and electroacupuncture+CsA groups received an intraperitoneal injection of CsA solution(0.2 mg/g)30 min before electroacupuncture intervention,once daily for 7 consecutive days.In experiment 1,depressive-like behavior was assessed using the open field,tail suspension,and sucrose preference tests.The spontaneous excitatory postsynaptic currents(sEPSC)and spontaneous inhibitory postsynaptic currents(sIPSC)parameters of hippocampal neurons were evaluated using brain slice patch clamp techniques.Western blotting was conducted to measure the expression levels of mitochondrial autophagy-related proteins PINK 1,phosphorylated PINK1(p-PINK1),Parkin,microtubule-associated protein 1A/1B-light chain 3-Ⅱ/Ⅰ(LC3-Ⅱ/Ⅰ),ubiquitin-binding protein(p62),and mitochondrial markers,including translocase of outer mitochondrial membrane 20(TOMM20),heat shock protein 60(HSP 60),and cytochrome c oxidase Ⅳ(COX Ⅳ).Immunofluorescence was used to detect PINK1 protein expression in the CA3 region of the hippocampus.Transmission electron microscopy was used to examine the ultrastructure of mitochondria in hippocampal neurons.On the basis of experiment 1,experiment 2 evaluated depressive-like behavior in mice using sucrose preference,open field,and tail suspension tests;Western blotting was used to detect the expressions of PINK1,p-PINK1,Parkin,LC3-Ⅱ/Ⅰ,p62,TOMM20,HSP 60,and COX Ⅳ proteins of hippocampus in mice.The mitochondrial ultrastructure was observed in hippocampal neurons using transmission electron microscopy.Results In experiment 1,compared with the blank group,the model and sham electroacupuncture groups exhibited a decrease in sucrose consumption rate,a decrease in the time spent in the center area,a reduced proportion of distance moved in the center area,and an increase in immobility time of tail suspension(P＜0.05).The sEPSC and sIPSC in hippocampal neurons decreased in both amplitude and frequency(P＜0.05).p-PINK1,Parkin,LC3-Ⅱ/Ⅰ,TOMM20,HSP 60,and COXⅣ expression levels in the hippocampus were reduced,whereas the p62 expression level was increased(P＜0.05).The average fluorescence intensity of PINK1 in the CA3 region of the hippocampus decreased(P＜0.05).The number of healthy mitochondria in hippocampal neurons was reduced,with numerous damaged mitochondrial structures observed.Compared to the model and sham electroacupuncture groups,the electroacupuncture group showed an increased in the time spent in the center area,a higher proportion of distance moved in the center area,and an elevated sucrose consumption rate.In contrast,the immobility time in the tail suspension test decreased(P＜0.05),whereas the amplitude and frequency of sEPSC and sIPSC in hippocampal neurons increased(P＜0.05).p-PINK1,Parkin,LC3-Ⅱ/Ⅰ,TOMM20,HSP 60,and COXⅣ expression levels in the hippocampus increased,whereas the p62 expression level decreased(P＜0.05).The average fluorescence intensity of PINK1 in the CA3 region of the hippocampus increased(P＜0.05).Additionally,mitochondrial damage in hippocampal neurons was alleviated,and a notable presence of autophagosomes mitophagy lysosomes was observed.In experiment 2,compared with the normal group,the mice in the CsA and electroacupuncture+CsA groups showed a decrease in the time spent in the center area and the proportion of distance moved in the center area,a decrease in sucrose consumption rate,and an increase in the immobility time in the tail suspension test(P＜0.05).p-PINK1,Parkin,LC3-Ⅱ/Ⅰ,TOMM20,HSP 60,and COX Ⅳ expression levels in the hippocampus decreased,whereas p62 expression increased(P＜0.05).Many damaged mitochondria were observed in hippocampal neurons.Conclusion Electroacupuncture may exert its antidepressant effects by promoting PINK1/Parkin pathway-mediated mitophagy to eliminate damaged mitochondria,thereby restoring the function of hippocampal neurons in depressive model mice.
