Effects of sEA on Slow Transit Constipation through the Microbiota-Gut-Brain Axis in Rats

To investigate the effect of sacral electroacupuncture (sEA) on the microbiota-gut-brain axis in the treatment of slow transit constipation, this study established a drug-induced model of slow transit constipation in rats and carried out sEA at the Baliao acupoints (BL31-BL34). On the 14th day of the therapeutic period (24 h fecal pellets), the aquaporin 3 (AQP3), 5-hydroxytryptamine (5-HT), and substance P (SP) transcripts from the distal colon and hypothalamus were analyzed. 16S rDNA has been widely used to analyze the diversity of the microbial communities. Therefore, in the present study, changes in the intestinal microbiota were analyzed by 16S rDNA gene sequencing. The results showed that sEA significantly increased the number of fecal pellets and the water content in the feces and reduced the reabsorption of intestinal water in 24 h. sEA also upregulated the level of SP mRNA expression in the distal colon and the hypothalamus, but downregulated the level of 5-HT mRNA expression in the distal colon. Moreover, sEA improved the Bacteroidetes to Firmicutes (B/F) ratio, which is beneficial to the general structure of the intestinal microflora. Our findings suggested that the microbiota-gut-brain axis constitutes a crucial pathological basis in the development of slow transit constipation. sEA improved the slow transit constipation by regulating the balance of the microbiota-gut-brain axis.