Effect of Magnolia officinalis Cortex Before and After Sweating on Distribution of Intestinal Flora and Levels of 5-HT and SP in IBS-C Rats / 中国实验方剂学杂志

ABSTRACT

ObjectiveTo investigate the mechanism of Magnolia officinalis cortex for constipation-type irritable bowel syndrome（IBS-C） rats before and after sweating. MethodIBS-C rat model was established by gavage of ice water， and rats were randomly divided into the blank group， model group， mosapride group（1 mg·kg-1）， M. officinalis cortex group（10 g·kg-1） and sweated M. officinalis cortex group（10 g·kg-1）. The changes of body weight， fecal number and fecal water content of rats were observed， 16S rRNA sequencing was used to detect the structural changes of fecal intestinal flora in rats， the levels of 5-hydroxytryptamine（5-HT） and substance P（SP） in colonic tissues of rats were determined by enzyme-linked immunosorbent assay（ELISA）. ResultCompared with the model group， the fecal water content and fecal number of mosapride group， M. officinalis cortex group and sweated M. officinalis cortex group were significantly increased（P<0.05）. At the phylum level， the top four species of flora abundance were Firmicutes， Bacteroidetes， Spirochaetes and Proteobacteria. Compared with the blank group， the proportion of Firmicutes in the model group was significantly reduced（P<0.05）， while the proportion of Spirochaetes was significantly increased（P<0.05）. Compared with the model group， the proportion of Firmicutes and Spirochaetes in M. officinalis cortex group and sweated M. officinalis cortex group tended to be similar to that in the blank group， and the proportion of Spirochaetes in sweated M. officinalis cortex group was lower than that of M. officinalis cortex group. At the family level， the top four species of flora abundance were Lactobacillaceae， S24_7， Ruminococcaceae， Bacteroidaceae， compared with the blank group， the proportion of Lactobacillaceae in the model group decreased significantly（P<0.05）， and its proportion in the M. officinalis cortex group and sweated M. officinalis cortex group increased significantly after administration（P<0.05）， and the flora structure of the two groups tended to be similar to that of the blank group. At the genus level， the top four species of flora abundance were Lactobacillus， Unspecified_S24_7， Bacteroides and Treponema. Compared with the blank group， the proportion of Lactobacillus in the model group decreased significantly（P<0.05）， while the proportion of Treponema increased significantly（P<0.05）. Compared with the model group， ratio of bacterial structure of Lactobacillus and Treponema in the M. officinalis cortex group and sweated M. officinalis cortex group tended to be similar to those in the blank group， indicating that M. officinalis cortex could restore the intestinal microbial structure of IBS-C rats before and after sweating. Compared with the model group， the 5-HT content in mosapride group was significantly reduced（P<0.05）， the contents of 5-HT and SP in the M. officinalis cortex group and sweated M. officinalis cortex group were significantly increased（P<0.01）， and the sweated M. officinalis cortex group was higher than the M. officinalis cortex group. ConclusionM. officinalis cortex can play a therapeutic role on IBS-C rats by regulating 5-HT pathway and intestinal flora structure before and after sweating.