Electro-acupuncture stimulation protects dopaminergic neurons from inflammation-mediated damage in medial forebrain bundle-transected rats.
Through producing a variety of cytotoxic factors upon activation, microglia are believed to participate in the mediation of neurodegeneration. Intervention against microglial activation may therefore exert a neuroprotective effect. Our previous study has shown that the electro-acupuncture (EA) stimulation at 100 Hz can protect axotomized dopaminergic neurons from degeneration. To explore the underlying mechanism, the effects of 100 Hz EA stimulation on medial forebrain bundle (MFB) axotomy-induced microglial activation were investigated. Complement receptor 3 (CR3) immunohistochemical staining revealed that 24 sessions of 100 Hz EA stimulation (28 days after MFB transection) significantly inhibited the activation of microglia in the substantia nigra pars compacta (SNpc) induced by MFB transection. Moreover, 100 Hz EA stimulation obviously inhibited the upregulation of the levels of tumor necrosis factor (TNF)-alpha and interleukin (IL)-1beta mRNA in the ventral midbrains in MFB-transected rats, as revealed by reverse transcriptase polymerase chain reaction (RT-PCR). ED1 immunohistochemical staining showed that a large number of macrophages appeared in the substantia nigra (SN) 14 days after MFB transection. The number of macrophages decreased by 47% in the rats that received 12 sessions of EA simulation after MFB transection. These data indicate that the neuroprotective role of 100 Hz EA stimulation on dopaminergic neurons in MFB-transected rats is likely to be mediated by suppressing axotomy-induced inflammatory responses. Taken together with our previous results, this study suggests that the neuroprotective effect of EA on the dopaminergic neurons may stem from the collaboration of its anti-inflammatory and neurotrophic actions.
Liu
Xian-Yu
XY
Neuroscience Research Institute, Peking University, Beijing 100083, PR China.
Zhou
Hui-Fang
HF
Pan
Yan-Li
YL
Liang
Xi-Bin
XB
Niu
Dong-Bin
DB
Xue
Bing
B
Li
Feng-Qiao
FQ
He
Qi-Hua
QH
Wang
Xin-Hong
XH
Wang
Xiao-Min
XM
D015669:Acupuncture Points; D015670:Acupuncture Therapy / Q000379:methods*; D000704:Analysis of Variance; D000818:Animals; D019771:Axotomy / Q000379:methods; D002452:Cell Count; D016923:Cell Death / Q000528:radiation effects; D004298:Dopamine / Q000378:metabolism*; D053331:Ectodysplasins; D004558:Electric Stimulation / Q000379:methods; D004660:Encephalitis / Q000473:pathology / Q000628:therapy*; D005260:Female; D007150:Immunohistochemistry / Q000379:methods; D007375:Interleukin-1 / Q000378:metabolism; D016177:Macrophage-1 Antigen / Q000378:metabolism; D008474:Medial Forebrain Bundle / Q000293:injuries / Q000502:physiology* / Q000528:radiation effects / Q000601:surgery; D008565:Membrane Proteins / Q000378:metabolism; D017628:Microglia / Q000378:metabolism / Q000528:radiation effects; D009474:Neurons / Q000378:metabolism / Q000528:radiation effects*; D012333:RNA, Messenger / Q000096:biosynthesis; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D013378:Substantia Nigra / Q000166:cytology*; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
D053331:Ectodysplasins; D007375:Interleukin-1; D016177:Macrophage-1 Antigen; D008565:Membrane Proteins; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D004298:Dopamine