Lactiplantibacillus plantarum MH-301 reduces Helicobacter pylori treatment-related adverse events via gut-vaginal axis: a randomized, double-blind, placebo-controlled trial

Background: Adverse events and microbiota dysbiosis resulting from Helicobacter pylori eradication therapy have become increasingly evident. This study investigates the adjunctive therapeutic effects of Lactiplantibacillus plantarum MH-301 in H. pylori eradication therapy, along with its effects on the gut and vaginal microbiota. Method: 257 sexually active, premenopausal women aged 18-50 years, diagnosed with H. pylori infection alongside chronic gastritis, were randomly allocated to undergo either bismuth-containing quadruple therapy (amoxicillin, furazolidone, potassium bismuth citrate, rabeprazole) combined with probiotics ( L. plantarum MH-301) or a placebo for 14 days. Stool samples and vaginal swabs were collected before and after treatment to facilitate high-throughput sequencing analysis. Result: The probiotic group exhibited lower incidences of bloating (10.2% vs 19.4%, P =0.037), constipation (2.3% vs 7.8%, P =0.048), and excessive vaginal discharge (3.1% vs 9.3%, P =0.040), and showed better treatment tolerability compared to the placebo group ( P <0.05), although no statistically significant difference in eradication rates between the two groups. High-throughput sequencing revealed that H. pylori eradication therapy led to a decrease in the relative abundance of Prevotella in the gut microbiota, and an increase in Streptococcus and Haemophilus . In the vaginal microbiota, Lactobacillus decreased while Gardnerella increased. Compared to the placebo group, the probiotic group showed a higher relative abundance of Megamonas , Prevotella , and Lactobacillus in the gut microbiota, and lower levels of Streptococcus and Haemophilus . In the vaginal microbiota, Gardnerella was significantly lower ( P <0.05). Correlation analysis revealed a positive association between gastrointestinal and vaginal adverse events, and a positive correlation of Lactobacillus in both gut and vaginal microbiota ( P <0.05). Conclusion: This study is the first to demonstrate at the clinical level that L. plantarum MH-301 reduces H. pylori treatment-related adverse events via gut-vaginal axis. In addition, microbiota modulation could be the possible mechanism through which it achieves its clinical efficacy.