ABSTRACT
OBJECTIVE: To observe the effect of electroacupuncture (EA) on the levels of Aβ 1-40 and Aβ 1-42 and neprilysin (NEP) protein in the temporal cortex of SAMP 8 mice with Alzheimer's disease (AD), so as to explore its mechanism underlying improvement of AD based on the theory of "mutual assistance of kidney and brain" in traditional Chinese medicine. METHODS: Eighteen male SAMP 8 mice were randomly assigned to 3 groups: model, EA and medication (memantine, n＝6/group), and 6 male homologous SAMR 1 mice were used as the normal control group. According to the "mutual assistance of kidney and brain" theory, EA (2 Hz，0.6 mA) was applied at "Baihui"(GV 20), bilateral "Shenshu"(BL 23) and "Taixi"(KI 3) for 15 min, once daily for 8 consecutive weeks. Mice of the medication group were treated with intragastric administration of memantine (20 mg•kg－1•d－1) for 8 weeks. The contents of Aβ 1-40 and Aβ 1-42 in the temporal cortex were assayed using ELISA, and the expression of NEP protein in the temporal cortex was detected using immunohistochemistry and Western blot (WB), separately. RESULTS: The contents of Aβ 1-40 and Aβ 1-42 were significantly higher in the model group than in the control group (P0.05). Immunohistochemistry stain showed that NEP-positive products mainly expressed in the perikaryon of neurons of the temporal cortex. CONCLUSION: EA intervention based on "mutual assistance of kidney and brain" theory has a good efficacy in up-regulating NEP expression and down-regulating Aβ 1-40 and Aβ 1-42 levels in the temporal cortex of AD mice, suggesting a potential effectiveness in the prevention and treatment of AD.
ABSTRACT
Objective To observe the effect of electroacupuncture at " Baihui"," Shenshu" and " Taixi" points on learning and memory,the expression of Aβ and insulin degrading enzyme(IDE) in the brain of SAMP8 mice.Methods Eight-month-old SAMR1 and SAMP8 mice were treated with electroacupuncture at " Baihui"," Shenshu" and "Taixi" points for eight consecutive weeks.The distribution and expression of Aβ and IDE in the brain prefrontal cortex of mouse were observed using immunohistochemistry and Western blot.Learning and memory function was assayed by Morris water maze(MWM).Results Compared with the normal control group,the brain prefrontal cortex of SAMP8 mice showed increased Aβ levels ((179.02± 15.11) ％),decreased IDE protein expression ((51.35 ± 14.94) ％).MWM showed the escape latency in SAMP8 mice was significantly longer than that in the control group (P＜0.05).Compared with the model group,Aβ levels in SAMP8 mice were markedly decreased in electroacupuncture group((119.72±9.21)％) and memantine-treated group ((116.84 ± 12.09) ％).IDE protein levels were increased by ((92.06 ± 8.05) ％) and ((83.84± 15.28) ％) after treatment with electroacupuncture and memantine relative to model group.MWM showed the escape latency was significantly shorter in SAMP8 mice treated with electroacupuncture and memantine than that in the model group(P＜0.05).Conclusion Electroacupuncture at " Baihui"," Shenshu" and "Taixi" points can inhibit Aβ levels,increase the expression of IDE and improve the learning and memory function of SAMP8 mice.