This is a single-center, open-label, single-arm interventional study designed to evaluate the effects of a functionally enhanced Limosilactobacillus reuteri probiotic preparation on intestinal immunity, gut microbiota balance, and intestinal function in elderly patients with functional bowel disorders. Participants aged 50-65 years with functional bowel disorders, including functional constipation, irritable bowel syndrome, or functional abdominal pain syndrome diagnosed according to Rome IV criteria, will receive the probiotic intervention.
The study will assess changes in senescence-associated secretory phenotype (SASP) expression levels to determine the extent of aging improvement, thereby evaluating the impact on intestinal immune aging. Clinical symptoms, including abdominal pain, abdominal distension, bowel movement frequency, and stool form, will also be recorded. In addition, changes in gut microbiota composition, key functional bacteria abundance, and tryptophan metabolites will be analyzed through fecal metagenomic and metabolomic approaches.
Safety and tolerability will be monitored throughout the study by recording adverse events and assessing routine laboratory parameters, including blood count and serum biochemical markers. This study aims to explore the potential mechanisms by which the probiotic preparation may improve gut immune function and microbiota balance, providing evidence for future clinical applications in elderly patients with functional bowel disorders.