Palmatine Inhibits the Pathogenicity of Aeromonas hydrophila by Reducing Aerolysin Expression

Abstract

Aeromonas hydrophila, an opportunistic aquatic pathogen widely spread in aquatic environments, is responsible for a number of infectious diseases in freshwater aquaculture. In addition, A. hydrophila can transmit from diseased fish to humans and results in health problems. The occurrence of antibiotic-resistant bacterial strains restricts the application of antibiotics and is responsible for failure of the treatment. Moreover, residues of antibiotics in aquatic products often threaten the quality and safety. Therefore, alternative strategies are called to deal with infections caused by antibiotic-resistant bacteria. Aerolysin, one of the most important virulence factors of A. hydrophila, is adopted as a unique anti-virulence target on the basis of the anti-virulence strategy to battling infections caused by A. hydrophila. Palmatine, an isoquinoline alkaloid from a variety of herbal medicines that showed no anti-A. hydrophila activity, could reduce hemolysis of the bacterium by decreasing aerolysin production. The results of the qPCR assay demonstrated that the transcription of the aerA gene was suppressed. Moreover, cell viability and in vivo study showed that palmatine treatment could decrease the pathogenicity of A. hydrophila both in vitro and in vivo. In summary, palmatine is a leading compound against A. hydrophila-associated infection in aquaculture by inhibiting the expression of aerolysin.

DFT Calculations, Pro-Apoptotic Effects, and Anti-Infective Investigations of Alkaloids Isolated from the Stem Bark Extract of Enantia chlorantha

“…Amongst the four compounds, palmatine exhibited better activity against Aeromonas hydrophilia with a zone of inhibition > 29mm. However, a study reported that palmatine was not effective against Aeromonas hydrophilia, an opportunistic pathogen of aquaculture, showing an MIC value of 256 µg/mL compared with the standard antibiotic Enrofloxacin with an MIC value of 4 µg/mL [27].…”

“…The structures of compounds 1-4 were drawn in Gauss view 6.0 (Semichem Inc., Shawnee, KS, USA). The DFT methods were used to optimize the ground state of all candidate compounds (1-4) using the Gaussian 09 package of Frisch et al (2019) as described in [27]. In this study, Becke's 3-parameter formula Hybrid Lee-Yang-Parr exchange-correlation (B3LYP) functions with a 6-31G (d,p) basis set was used for gas-phase compound optimization [28].…”

Microbiological Hazard Analysis of Car Wash Wastewater

“…Bacterial groups: ▲-Firmicutes, • -Enterobacteria, ■ -Proteobacteria have become multidrug resistant [58]. One of the bacteria resistant to the commercial antibiotics is Aeromonas hydrophila which can be transmitted by bioareosols [59]. Bacillus subtilis strains are resistant to antibiotics used in oral bacteriotherapy [60].…”

The Natural Alkaloid Palmatine Selectively Induces Mitophagy and Restores Mitochondrial Function in an Alzheimer’s Disease Mouse Model

“…Previous studies have shown that palmatine has protective effects on the liver and kidney and antidiabetic effects in various in vitro and in vivo models [14]. In addition, cardioprotective [15], neuroprotective [16], and antibacterial functions of palmatine have also been reported [17,18]. Although previous studies have shown that palmatine has various physiological effects, its role in mitochondrial function and mitophagy has not been investigated.…”