Electroacupuncture could balance the gut microbiota and improve the learning and memory abilities of Alzheimer's disease animal model

Abstract

Alzheimer's disease (AD), as one of most common dementia, mainly affects older people from the worldwide. In this study, we intended to explore the possible mechanism of improving cognitive function and protecting the neuron effect by electroacupuncture.

Method: We applied senescence-accelerated mouse prone 8 (SAMP8) mice as AD animal model, used Morris water maze, HE staining, 16S rDNA amplicon sequencing of gut microbiota and ELISA to demonstrate our hypothesis.

Results: electroacupuncture improved the learning and memory abilities in SAMP8 mice (P<0.05) and could protect the frontal lobe cortex and hippocampus of SAMP8 mice; electroacupuncture significantly decreased the expression of IL-1β (P<0.01), IL-6 (P<0.01) and TNF-α (P<0.01 in hippocampus, P<0.05 in serum) in serum and hippocampus; electroacupuncture balanced the quantity and composition of gut microbiome, especially of the relative abundance in Delta-proteobacteria (P<0.05) and Epsilon-proteobacteria (P<0.05).

Conclusion: electroacupuncture treatment could inhibit the peripheral and central nerve system inflammatory response by balancing the gut microbiota.

Fig 1. Results of Morris water maze test.

(a, the tends of escape time in each group during the five training days of hidden platform test; b, comparing the escape time of each group during the five training days of hidden platform test; c, the ratio of swimming time in the target quadrant and total swimming time of each group in the probe test.).

Fig 2. Results of HE staining.

(a, the HE staining of each group at hippocampus, *400; b, HE staining of each group at frontal lobe cortex, *400.).

Fig 3. Differences of SAMP8 and SAMR1 mice in Gut Microbiota.

(a, comparing the OTUs numbers of each sample in control group and AD group; b, gut microbiota community structure of control group and AD group; c-d, linear discriminant analysis (LDA) coupled with effect size measurements, different species of control group and AD group; e, indicator analysis of indicator species in control group and AD group.).

Fig 4

(a, comparing the OTUs numbers of each group; b, gut microbiota community structure of each group; c-d, linear discriminant analysis (LDA) coupled with effect size measurements, different species of each group; e, indicator analysis of indicator species in each group.).

Fig 5

(a, comparation the relative abundance of Bacteroidia in each group; b, comparation the relative abundance of Clostridia in each group; c, comparation the ratio of Bacteroidia and Clostridia in relative abundance of each group; d, comparation the relative abundance of Delta-proteobacteria in each group; e, comparation the relative abundance of Epsilon-proteobacteria in each group; f, comparation the relative abundance of Deferribacteres in each group.).

Fig 6

(a, comparation of IL-1β content in serum and hippocampus of each group; b, comparation of IL-6 content in serum and hippocampus of each group; c, comparation of TNF-α content in serum and hippocampus of each group.).