Emodin Improves Intestinal Health and Immunity through Modulation of Gut Microbiota in Mice Infected by Pathogenic Escherichia coli O1

Abstract

The effect of emodin on the intestinal mucosal barrier of a mouse E. coli O1-induced diarrhea model was observed. Following successful establishment of a diarrhea model, the mice were treated with drugs for seven days. Intestinal lesions and the shape and the number of goblet cells were assessed via hematoxylin-eosin and periodic-acid-Schiff staining, while changes in inflammatory factors, ultrastructure of the small intestine, expression of MUC-2, and changes in the intestinal microbiota were analyzed via RT-PCR, electron microscopy, immunofluorescence, and 16S rRNA sequencing. Examination showed that emodin ameliorated pathological damage to the intestines of diarrheic mice. RT-PCR indicated that emodin reduced TNF-α, IL-β, IL-6, MPO, and COX-2 mRNA levels in duodenal tissues and increased the levels of sIgA and MUC-2 and the number of goblet cells. Microbiome analysis revealed that Escherichia coli O1 reduced bacterial richness and altered the distribution pattern of bacterial communities at the phylum and order levels in cecum contents. Notably, pathogenic Clostridiales and Enterobacteriales were significantly increased in diarrheic mice. However, emodin reversed the trend. Thus, emodin protected against intestinal damage induced by E. coli O1 and improved intestinal mucosal barrier function in mice by increasing the abundance of beneficial intestinal microbiota and inhibiting the abundance of harmful bacteria, thereby alleviating diarrhea.

Dietary emodin alleviates lipopolysaccharide-induced intestinal mucosal barrier injury by regulating gut microbiota in piglets

“…In this investigation, LPS-challenge increased Proteobacteria abundance and decreased Bacteroidetes abundance, but ED reversed the adverse changes induced by LPS. Consistent with our findings, Gao et al. (2021) found that ED increased Bacteroidetes abundance while decreasing Proteobacteria abundance in a mice model of diarrhea.…”

“…Supplemental ED relieved LPS-induced adverse effects on intestinal morphology of piglets. Similarly, ED was found to reduce pathological damage of intestinal mucosa in septic rats ( Li et al., 2020 ) and E. coli challenged mice ( Gao et al., 2021 ). Plasma D-lactate and DAO are sensitive circulating markers of intestinal permeability ( Arrieta et al., 2006 ).…”

“…Moreover, ED could attenuate lipopolysaccharide (LPS) induced intestinal epithelial barrier dysfunction through NF-κB pathway modulation ( Qi et al., 2014 ; Piao et al., 2020 ; Qian et al., 2020 ). Gao et al. (2021) reported that ED decreased the damage to the mucosal barrier function of the intestine in mice infected with Escherichia coli by altering the intestinal microbiota, thereby alleviating diarrhea.…”

Bacteroides acidifaciens in the gut plays a protective role against CD95-mediated liver injury

“…Differentiated gut microbiota compositions are often used to study the regulatory function of intestinal flora. Previous studies showed that a variety of food or drug components, such as pectin, 22 , 50 a high-fiber diet, 51 a high-fat diet, 52 emodin, 53 quercetin 54 and various antibiotics, 55 changed the composition of the intestinal flora and affected its function. Artificially induced intestinal flora dysbiosis using antibiotics in healthy mice raised in the same living environment generated large differences in gut microbiota due to the distinct antimicrobial spectrum, which likely produces considerable differences in pathological responses.…”

Effect of natural polyphenols in Chinese herbal medicine on obesity and diabetes: Interactions among gut microbiota, metabolism, and immunity

“…The key mechanism of both microbiota is that they are producers of SCFAs, and the effects of SCFAs have been summarized above ( 78 ). Furthermore, Akkermansia participated in the repair of the intestinal barrier through upregulating the expression of ZO-1 and occludin in vivo and in vitro ( 74 ). As a pivotal source of acetic acid production, Lactobacillus was also regarded as a probiotic, and its curative effect was detected in obese subjects with T2DM through an RCT of fecal microbiota transplantation ( 77 ).…”