Tannins extract from Galla Chinensis can protect mice from infection by Enterotoxigenic Escherichia coli O101

Xu Song,Yi Yang,Min Cui,Juan Hang,Mengxue He,Lixia Li,Renyong Jia,Zhongqiong Yin,Yuanfeng Zou,Lu Bai,Junzhi Li

doi:10.1186/s12906-021-03261-x

Xu Song, Yi Yang + Show 9 more

Open Access

https://doi.org/10.1186/s12906-021-03261-x

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Abstract

BackgroundEnterotoxigenic Escherichia coli (ETEC) is classically associated with acute secretory diarrhea, which induces 2 million people death in developing countries over a year, predominantly children in the first years of life. Previously, tannins (47.75%) were extracted from Galla Chinensis and prepared as Galla Chinensis oral solution (GOS) which showed significant antidiarrheal activity in a castor oil-induced diarrhea in mice. Whether the tannins extract were also effective in treatment of ETEC-induced diarrhea was determined in this study.MethodsMice were randomly divided into 6 groups (n = 22). The mice in the normal and untreated groups were given normal saline. Three GOS-treated groups were received different concentrations of GOS (5, 10 and 15%, respectively) at a dose of 10 mL/kg. Mice in the positive control group were fed with loperamide (10 mg/kg). The treatment with GOS started 3 days before infection with ETEC and continued for 4 consecutive days after infection. On day 3, mice were all infected with one dose of LD50 of ETEC, except those in the normal group. Survival of mice was observed daily and recorded throughout the study. On days 4 and 7, samples were collected from 6 mice in each group.ResultsGOS could increase the survival rate up to 75%, while in the untreated group it is 43.75%. The body weights of mice treated with 15% GOS were significantly increased on day 7 in comparison with the untreated group and the normal group. GOS-treatment recovered the small intestine coefficient enhanced by ETEC-infection. The diarrhea index of mice treated with GOS was significantly decreased. GOS increased the levels of IgG and sIgA in the terminal ileum and decreased the levels of pro-inflammatory cytokines (IFN-γ, TNF-α, IL-1β, IL-6 and IL-8) in serum. GOS could increase the amount of intestinal probiotics, Lactobacilli and Bifidobacteria. GOS could alleviate colon lesions induced by ETEC-infection. GOS showed higher potency than loperamide.ConclusionsGOS could be a promising drug candidate for treating ETEC infections.

Highlights

Enterotoxigenic Escherichia coli (ETEC) is classically associated with acute secretory diarrhea, which induces 2 million people death in developing countries over a year, predominantly children in the first years of life
Enterotoxigenic Escherichia coli (ETEC) are a diverse group of pathogens that have in common the ability to colonize the small intestine, which are classically associated with acute secretory diarrhea [1]
We found that tannins extract showed significant antidiarrheal activity in a castor oil-induced diarrhea model in mice [21]

Summary

Introduction

Enterotoxigenic Escherichia coli (ETEC) is classically associated with acute secretory diarrhea, which induces 2 million people death in developing countries over a year, predominantly children in the first years of life. Whether the tannins extract were effective in treatment of ETEC-induced diarrhea was determined in this study. Enterotoxigenic Escherichia coli (ETEC) are a diverse group of pathogens that have in common the ability to colonize the small intestine, which are classically associated with acute secretory diarrhea [1]. 2 million of these people living in developing countries would die as a result of these diseases in a year, predominantly children in the first years of life [5]. Multiple pathogens are responsible for this suffering and death in developing countries, but ETEC is regarded as the most common bacterial cause of diarrhea [6]. In the present study, the O101 strain is used to establish a mouse model of ETEC -induced diarrhea

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