AUTHOR=Chen Kai , Qin Ting , Pan Liangkun , Bing Xuwen , Xi Bingwen , Xie Jun 

TITLE=Effects of glycyrrhetinic acid β on growth and virulence of Aeromonas hydrophila

JOURNAL=Frontiers in Microbiology

VOLUME=14

YEAR=2023

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2023.1043838

DOI=10.3389/fmicb.2023.1043838

ISSN=1664-302X

ABSTRACT=<p><italic>Aeromonas hydrophila</italic> is a significant pathogen to freshwater farmed animals, and antibiotics are usually used to control the bacterial septicemia caused by <italic>A. hydrophila</italic>. Due to the severe situation of development and spread of antibiotic resistance, there are stricter restrictions on antibiotics used in aquaculture. To evaluate the feasibility of glycyrrhetinic acid β (GA) as an alternative therapy against bacterial infection, in this study, an <italic>A. hydrophila</italic> isolated from diseased fish is used to test the antibacterial, anti-virulence activity and therapeutic effect of GA <italic>in vitro</italic> and <italic>in vivo</italic>, respectively. Results showed that GA did not affect the growth of <italic>A. hydrophila in vitro</italic>, while it could down-regulate (<italic>p</italic> &lt; 0.05) the mRNA expression of the hemolysis-related genes <italic>hly</italic> and <italic>aer</italic>A, and significantly inhibited (<italic>p</italic> &lt; 0.05) hemolytic activity of <italic>A. hydrophila</italic>. In addition, <italic>in vivo</italic> test showed that oral administration of GA was ineffective in controlling acute infections caused by <italic>A. hydrophila</italic>. In conclusion, these findings suggested that GA was a potential anti-virulence candidate against <italic>A. hydrophila</italic>, but the application of GA for the prevention and treatment of <italic>A. hydrophila</italic>-related diseases was still a long way.</p>