Author:
Zhao Xueqin,Luo Weiyu,Wang Lei,Zhu Chunling,Xue Xianghong,Xia Xiaojing,Wu Xilong,Bai Yueyu,Hu Jianhe
Abstract
Abstract
Background
Escherichia coli is a facultative anaerobic bacterium that normally resides in the gastrointestinal tract of humans and animals but can cause diarrhea and enteritis. MPX is an antimicrobial peptide extracted from wasp venom and has potent bactericidal effects against many bacteria. This study aimed to investigate the mechanism of MPX’s bactericidal activity against E. coli in vitro, its effect on IPEC-J2 cell apoptosis and barrier function, and its therapeutic efficacy against E. coli infection in mice.
Methods
The effects of MPX on E. coli were investigated in vitro, at the cellular level, and in vivo.
Results
The study found that the MIC of MPX against E. coli was 31.25 µg/mL, and scanning electron microscopy showed that MPX caused the bacteria to become smaller in size with leaked contents. Additionally, NPN, PI, and DiSC3(5) results showed that MPX positively correlated with the fluorescence intensity. MPX significantly inhibited E. coli biofilm formation. Furthermore, MPX effectively reduced IPEC-J2 cell apoptosis, regulated ZO-1, Occludin, and Claudin-1 expression through the Rac1 pathway, and alleviated the pathological damage in the intestine, as shown by H&E staining results. qRT-PCR results indicated that MPX increased TFF3 mRNA expression in the jejunum and colon.
Conclusions
This study is the first to explore the mechanism of MPX's bactericidal activity against E. coli in vitro, providing a foundation for developing new drugs to treat bacterial infections.
Graphical Abstract
Funder
National Natural Science Foundation of China
National Key R&D Program of China
the Leading Talents of Scientific and Technological Innovation in the Central Plains
the Outstanding Youth Foundation of He’nan Scientific Committee
Youth Innovation Technology Project of Higher School in Shandong Province
Publisher
Springer Science and Business Media LLC
Subject
General Earth and Planetary Sciences,General Environmental Science
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