Electroacupuncture protected pyramidal cells in hippocampal CA1 region of vascular dementia rats by inhibiting the expression of p53 and Noxa.
OBJECTIVE
Clinically electroacupuncture (EA) is proved an effective therapy for vascular dementia (VD), but their mechanisms remain uncertain. The aim of this study was to determine whether EA protects pyramidal cells from apoptosis in hippocampus of a VD rat model by inhibiting the expression of p53 and Noxa.


METHODS
One month after a VD animal model was established by bilateral occlusion of common carotid arteries, EA treatment was given at "Baihui" (DU20), "Dazhui" (DU14), and "Shenshu" (BL23). The learning and memory ability was assessed by Morris water maze. Neuronal apoptosis in hippocampus was evaluated with hematoxylin-eosin (HE) staining, and the expression of p53 and Noxa was analyzed by confocal laser scanning microscope with immunofluorescence staining.


RESULTS
Expressions of p53 and Noxa in the EA group and sham-operated group were less than in the VD model group (P < 0.01), and the expression of p53 was positively correlated to expression of Noxa in hippocampus of VD rats (r = 0.918, P < 0.01). EA treatment could reduce the amount of apoptotic neurons in hippocampal CA1 area of rats with VD. The average latency in the Morris water maze test was significantly shorter, and escape strategies improved from edge and random searches to more linear swim pathway in the EA group compared with the VD model group (P < 0.01).


CONCLUSIONS
The increasing expressions of p53 and Noxa play important roles in the pathogenesis of VD. EA improves learning and memory ability and protects pyramidal cells from apoptosis by blocking expression of p53 and Noxa in the hippocampal CA1 region of VD rats. These results suggest a novel mechanism of EA treatment to VD.
Department of Integrative Medicine, Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian Province, China.
Yanzhen
Y
Zhu
Yanjun
Y
Zeng
D000818:Animals; D017209:Apoptosis / Q000502:physiology; D001522:Behavior, Animal / Q000187:drug effects; D056547:CA1 Region, Hippocampal / Q000473:pathology*; D016893:Carotid Stenosis / Q000150:complications / Q000473:pathology; D015140:Dementia, Vascular / Q000378:metabolism* / Q000473:pathology*; D004195:Disease Models, Animal; D015671:Electroacupuncture; D005455:Fluorescent Antibody Technique; D008297:Male; D018782:Maze Learning / Q000187:drug effects; D018613:Microscopy, Confocal; D016612:Paraffin Embedding; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000096:biosynthesis*; D017966:Pyramidal Cells / Q000473:pathology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013028:Space Perception / Q000187:drug effects; D016159:Tumor Suppressor Protein p53 / Q000096:biosynthesis*
C539472:Pmaip1 protein, rat; D019253:Proto-Oncogene Proteins c-bcl-2; D016159:Tumor Suppressor Protein p53