Intervention With Lacticaseibacillus paracaseiPC-01 Fermented Milk Beverage Ameliorates Functional Dyspepsia and Modulates Gut Microbiome: A Pilot Study.

Functional dyspepsia (FD) is a common chronic gastrointestinal disorder characterized by persistent or recurrent epigastric symptoms in the absence of detectable structural abnormalities. In this pilot study, we explored whether a Lacticaseibacillus paracasei PC-01 (PC-01) fermented milk beverage alleviates FD symptoms. Fifty-five patients with FD were randomized into an experimental group (EP, n = 37) receiving the PC-01 fermented milk beverage (5.0 × 108 CFU/mL, 200 mL/day) or a control group (CP, n = 18) receiving the active comparator, an acidified milk beverage (non-fermented, without PC-01) (200 mL/day). The interventions lasted 28 days, with symptom scores on the 7-point Global Overall Symptom Scale (GOSS) and Gastrointestinal Symptom Rating Scale (GSRS), and fecal samples were collected at baseline (day 0), 14, and 28. Consumption of the PC-01 fermented milk beverage in this pilot study was associated with improvements in FD symptoms, and a higher effective response rate was observed in the EP group than in the CP group (p = 0.04). Metagenomic analysis revealed that, compared with the CP group, the EP group exhibited significant enrichment of potentially beneficial bacteria (e.g., Blautia) and a reduction in potentially pathogenic bacteria (e.g., Clostridium paraputrificum), accompanied by significant downregulation of the fatty acid β-oxidation I (FAO-PWY) pathway. We acknowledge that the limitation of this pilot study is that the acidified milk beverage used as the control might also exert certain effects on gastrointestinal symptoms and gut microbiota, which could not be fully avoided due to the lack of a fully inert placebo. Collectively, the findings of this preliminary study indicate that the PC-01 fermented milk beverage may alleviate FD-related symptoms and modulate the gut microbiome and metabolic pathways, highlighting its potential in ameliorating FD-associated symptoms. Further large-sample, multi-center, and long-term clinical studies are warranted to verify these preliminary results and establish the long-term efficacy and safety of FD management.