针刺抑制p53mRNA过表达并改善SAMP8小鼠的认知能力

目的]探讨针刺延缓脑衰老的机制。方法]将快速老化痴呆小鼠(SAMP8)及其正常同源对照小鼠(SAMR1)分为SAMR1对照组、SAMP8对照组、SAMP8针刺组和SAMP8非穴组。针刺组给予"益气调血,扶本培元"针法治疗;非穴组针刺双胁下两个固定非穴位点;其余两组给予等量的捉抓刺激;每天1次,持续15 d。采用Morris水迷宫测定动物的学习记忆能力;逆转录-聚合酶链反应(RT-PCR)法测定海马p53mRNA表达。结果]与SAMR1对照组相比,SAMP8各组的学习能力及记忆保持能力出现明显损伤,表现为思维僵化、学习过程减慢;其海马p53mRNA表达明显升高。针刺明显改善SAMP8的认知能力,并降低海马p53mRNA表达,甚至低于正常组。结论]SAMP8的认知损害与p53基因表达异常有关,针刺通过调节p53mRNA表达延缓SAMP8脑衰老的进程,是针刺改善衰老后认知能力下降的原因之一。

Acupuncture inhibits overexpression of p53 mRNA and improves cognitive ability in SAMP8 mice

Objective] To explore the mechanism of acupuncture in delaying the brain aging. Methods] The SAMP8 mice (senescence accelerated mouse prone 8) and their normal control, SAMR1 mice (senescence accelerated mouse resistant 1) were assigned to the following four groups: SAMR1 control group (Rc), SAMP8 control group (Pc), SAMP8 acupuncture group (Pa) and SAMP8 non-acupoint group (Pn). Pa was treated with "Yiqi Tiaoxue and Fuben Peiynan" acupuncture once a day for 15 days. For the Pn mice, the nonacupoints point at hypochondrium on both sides of the body were stimulated. The two control groups were grasped in the same amount of time and with the same extent of strength as that in Pa and Pn. Spatial learning and memory of mice was assessed by Morris water maze. The expression of p53mRNA was determined by RT-PCR. Results] The cognitive abilities of SAMP8 damaged apparently, which was showed by rigid thinking pattern and slow learning process in their Morris water maze tasks. The expression of p53mRNA in hippocampus of SAMP8 increased more obviously than that of SAMR1. After acupuncture treatment, the cognitive function of SAMP8 mice improved significantly and the expression of p53mRNA in hippocampus declined sharply, which even lower than that of the Rc group. Conclusion] The brain aging of SAMP8 mice is correlated with the expression of p53mRNA. Acupuncture treatment can delay the aging process by decreasing p53 mRNA level, which can partly explain why and how acupuncture worked in improving age-related cognitive impairments.