高盐饮食对小鼠认知功能的影响 及其与肠道菌群的关系.

Abstract：Objective To investigate the effect of high-salt diet (HSD) on cognitive function of mice and to explore whether it is related to the disorders of gut microbiota. Methods Twenty C57BL/6 male mice were randomly divided into two groups：the ND group (n=10) and the HSD group (n=10) . The mice in the ND group were fed with ordinary maintenance fodder, and the mice in the HSD group were fed with high-salt fodder. They both were treated for 16 weeks. The cognitive function of mice was tested via Y maze and novel object recognition test, respectively, and we recorded the spontaneous response rate and preference rate data. Then fecal samples were collected for the total bacterial RNA extraction and 16S rDNA V4 fragment amplification by PCR method. We analyzed the differences of microbial composition between two groups by high-throughput sequencing. The relative expression levels of synaptophysin (SYP) mRNA in the brain tissues of two groups were detected by real-time fluorescence quantitative PCR method. Results The mice in the HSD group had significantly lower rate of spontaneous reaction and preference in both Y maze and novel object recognition test, as well as lower levels of SYP expression in brain tissues as compared with those of the ND group (all P<0. 05), and there were no significant differences in OTU number or α-diversity which included four indexes, Ace, Chao1, Shannon and Simpson, rspectively, between these two groups (all P>0. 05) . In the level of phylum, there were no significant differences in the the relative abundances of Birmicutes, Bacteroidetes, Proteobacteria, or Actinobacteria between these two groups (all P> 0. 05) . In the level of species, the relative abundances of Akkermansia muciniphila, Bacillus acidifaciens and Faecalibaculum rodentium were higher, while the relative abundance of Clostridium leptum was lower in the HSD group than in the ND group (all P<0. 05. Conclusion HSD impairs cognitive function in mice, which may be related to the disorders of gut microbiota. [ABSTRACT FROM AUTHOR]