Effect of Bushen Jianpi Kaixin formula on cognitive function and the expression of autophagy related proteins in Alzheimer’s disease model rats / 中华行为医学与脑科学杂志

ABSTRACT

Objective:To investigate the effect and mechanism of the Bushen Jianpi Kaixin formula on the learning and memory ability of Alzheimer's disease (AD) model rats.Method:A total of 72 SPF grade male SD rats were divided into control group, model group, Bushen group, Jianpi group, Kaixin group and Bushen Jianpi Kaixin group according to the random number table method ( n=12 in each group). The rats were intraperitoneally injected with D-galactose once a day for 6 weeks to replicate the model of AD.And the rats in different medication groups were given corresponding administration (Bushen formula gavage 3.60 g·kg -1·d -1, Jianpi formula gavage 4.05 g·kg -1·d -1, Kaixin formula gavage 2.34 g·kg -1·d -1, Bushen Jianpi Kaixin formula gavage 9.99 g·kg -1·d -1), while rats in control group and model group were treated with equal volume of 0.9% sodium chloride solution once a day for 28 days.The learning and memory ability was tested by Morris water maze.The expressions of phosphoinositide 3-kinase(PI3K), protein kinase B(Akt) and mammalian target of rapamycin(mTOR) in cerebral cortical tissues were detected by immunohistochemistry.The relative mRNA levels of p62 and Beclin in brain cortical tissue were detected by RT-PCR.SPSS 25.0 software was used for data processing, one-way ANOVA was used for inter group comparisons, and LSD test was used for further pairwise comparisons. Results:Morris water maze results showed statistically significant differences in escape latency and the times of crossing platform among the six groups ( F=368.10, 47.43, both P<0.01). The escape latency of Bushen Jianpi Kaixin group((29.30±1.64) s) was shorter than that of model group((55.58±3.23) s) ( P<0.01), the times of crossing platform ((5.17±0.72) times) in Bushen Jianpi Kaixin group was higher than that of model group (1.50±0.52)time, P<0.01). Compared with the Bushen Jianpi Kaixin group, the escape latencies of Bushen group, Jianpi group and Kaixin group were longer (all P<0.01), the times of crossing platform in Bushen group was lower ( P<0.01). Immunohistochemical results showed statistically significant differences in the positive protein expression of PI3K, Akt, and mTOR proteins among the six groups ( F=68.52, 22.22, 31.52, all P<0.01). Compared with the model group, the levels of positive protein of PI3K ((0.47±0.15), (0.57±0.12)), Akt ((0.31±0.02), (0.38±0.02)), and mTOR ((0.22±0.18), (0.28±0.11)) in Bushen Jianpi Kaixin group were less (all P<0.01). Compared with the Bushen Jianpi Kaixin group, the levels of positive protein of PI3K and mTOR of Bushen group, Jianpi group and Kaixin group were higher (all P<0.01). RT-PCR results showed statistically significant differences in the relative mRNA levels of Beclin and p62 among all the groups ( F=8.79, 21.01, both P<0.01). The relative mRNA level of Beclin in Bushen Jianpi Kaixin group was higher than that of the model group ((0.97±0.07), (0.64±0.12)), and the relative mRNA level of p62 of Bushen Jianpi Kaixin group was less than that of model group((0.98±0.16), (1.16±0.24))(both P<0.01). The relative mRNA levels of p62 in Bushen group, Jianpi group and Kaixin group were higer than those of Bushen Jianpi Kaixin group (all P<0.05). Conclusion:Bushen Jianpi Kaixin formula can improve cognitive impairment and learning and memory ability in AD model rats.The mechanism may be related to the regulation of PI3K/Akt/mTOR autophagy pathway.The combination prescription is better than the split prescription.