Epigallocatechin gallate protects mice from Salmonella enterica ser. Typhimurium infection by modulating bacterial virulence through quorum sensing inhibition

Guoqiang Cheng; Shanqiu Jian; Wen Li; Liangchun Yan; Tiezhu Chen; Tingting Cheng; Zongxiu Liu; Gang Ye; Huaqiao Tang; Li Zhang

doi:10.3389/fcimb.2024.1432111

Epigallocatechin gallate protects mice from Salmonella enterica ser. Typhimurium infection by modulating bacterial virulence through quorum sensing inhibition

Front Cell Infect Microbiol. 2024 Oct 16:14:1432111. doi: 10.3389/fcimb.2024.1432111. eCollection 2024.

Authors

Affiliations

¹ Animal Experiment Center, Sichuan Academy of Chinese Medicine Sciences, Chengdu, China.
² College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.
³ Department of Science, Sichuan Academy of Agricultural Sciences, Chengdu, China.
⁴ Department of Innovation, Chengdu Qiankun Animal Pharmaceutical Co., Ltd, Chengdu, China.

Abstract

Salmonella enterica ser. Typhimurium is a common pathogen that poses a considerable public health threat, contributing to severe gastrointestinal diseases and widespread foodborne illnesses. The virulence of S. Typhimurium is regulated by quorum sensing (QS) and the type III secretion system (T3SS). This study investigated the inhibitory effects and anti-QS activity of epigallocatechin gallate (EGCG), which is a bioactive ingredient found in green tea, on the virulence of S. Typhimurium. In vitro bacterial experiments demonstrated that EGCG inhibited the production of autoinducers, biofilm formation, and flagellar activity by downregulating the expression of AI-1, AI-2, Salmonella pathogenicity islands (SPI)-1, SPI-2, and genes related to flagella, fimbriae, and curli fibers. In a mouse model of S. Typhimurium-induced enteritis, EGCG considerably reduced intestinal colonization by S. Typhimurium and alleviated intestinal damage. In conclusion, EGCG protects the intestines of mice infected with S. Typhimurium by inhibiting QS-induced virulence gene expression, demonstrating its potential as a therapeutic agent for controlling S. Typhimurium infections.

Keywords: Salmonella enterica ser. Typhimurium; epigallocatechin gallate; quorum sensing; type III secretion system; virulence.

MeSH terms

Animals
Anti-Bacterial Agents / pharmacology
Bacterial Proteins / genetics
Bacterial Proteins / metabolism
Biofilms* / drug effects
Catechin* / analogs & derivatives
Catechin* / pharmacology
Disease Models, Animal*
Female
Flagella / drug effects
Gene Expression Regulation, Bacterial / drug effects
Genomic Islands
Intestines / microbiology
Mice
Mice, Inbred BALB C
Quorum Sensing* / drug effects
Salmonella Infections / drug therapy
Salmonella Infections / microbiology
Salmonella typhimurium* / drug effects
Salmonella typhimurium* / genetics
Salmonella typhimurium* / pathogenicity
Type III Secretion Systems / drug effects
Type III Secretion Systems / genetics
Type III Secretion Systems / metabolism
Virulence / drug effects
Virulence Factors / genetics
Virulence Factors / metabolism

Substances

epigallocatechin gallate
Catechin
Bacterial Proteins
Virulence Factors
Type III Secretion Systems
Anti-Bacterial Agents

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. This work was supported by the Science & Technology Department of Sichuan Province (2023JDKY0027), Sichuan provincial administration of traditional Chinese medicine (2024MS248), and Key Open Laboratory of Traditional Chinese Veterinary Medicine, National Ethnic Affairs Commission ([2022] No. 08).