Molecular dynamics simulation-driven focused virtual screening and experimental validation of Fisetin as an inhibitor of Helicobacter pylori HtrA protease

Abstract

Helicobacter pylori (H. pylori, Hp) is a primary contributor to various stomach diseases, including gastritis and gastric cancer. This bacterium can colonize gastric epithelial cells, compromising their integrity and leading to the development of these conditions. While antibiotics are the mainstay of treatment for H. pylori infections, their widespread use has led to serious issues with drug resistance. High-temperature requirement A (HtrA), an important virulence factor of H. pylori, emerges as a promising target for the design of new inhibitors. In this study, we employed molecular docking, molecular dynamics simulation (MDs), and in vitro experimental validation to identify potential active components that specifically target HtrA, effectively combating H. pylori. Based on the results of molecular docking and literature reports, 8 potential natural compounds targeting HtrA were found: Camelliaside B, Rehmanioside A, Hesperidin, Quercetin, Fisetin, Colchicine, Apigenin and Geniposide. MDs further revealed that Fisetin, Geniposide, and Quercetin show promising stability and interactions with HtrA. Importantly, in vitro experiments, including casein hydrolysis assays and antibacterial sensitivity tests, demonstrated that Fisetin observably inhibited the hydrolysis of casein by HtrA and effectively suppressed the growth of H. pylori. Overall, our findings highlight Fisetin as a potential therapeutic drug that targets HtrA, offering new tack for the development of lead compounds and potential drugs against H. pylori infections.