Prebiotic, probiotic, and chlorophyllin interventions differentially attenuate melphalan-induced intestinal injury and modulate gut metabolite profiles

Introduction Melphalan treatment can cause substantial gastrointestinal toxicity, yet the relationship between chemotherapy-induced epithelial injury, intestinal barrier dysfunction, and alterations in the gut metabolic environment remains incompletely understood. Here, we investigated whether nutritionally and mechanistically distinct interventions could attenuate melphalan-induced intestinal injury and associated metabolic perturbations. Methods C57BL/6 mice were allocated to vehicle control, melphalan alone, melphalan plus fructo-oligosaccharides (FOS), melphalan plus a commercial probiotic preparation containing Lacticaseibacillus paracasei Shirota, or melphalan plus chlorophyllin ( n = per group). Interventions were administered orally for 3 days before and 3 days after a single oral dose of melphalan (10 mg/kg). Intestinal toxicity was characterized through physiological outcomes, circulating markers of epithelial injury and barrier dysfunction, intestinal protein expression, and targeted LC–MS/MS profiling of short-chain fatty acids, bile acids, and indole-derived metabolites. Results Melphalan induced body-weight loss and shortening of the small intestine, accompanied by reduced plasma citrulline and increased circulating lipopolysaccharide and occludin, consistent with enterocyte loss and impaired intestinal barrier integrity. These alterations coincided with broad reductions across multiple metabolite classes, indicating substantial disruption of the intestinal metabolic environment. FOS, the commercial probiotic preparation, and chlorophyllin attenuated body-weight loss and restored small-intestinal length and plasma-marker levels toward vehicle-control values. FOS and the probiotic preparation significantly increased selected SCFAs and bile acids, whereas the probiotic preparation and chlorophyllin significantly increased selected tryptophan-derived metabolites. Chlorophyllin also significantly increased taurocholate relative to melphalan alone. Discussion These findings support further investigation of gut-directed nutritional interventions as strategies to mitigate chemotherapy-associated intestinal injury, with the exploratory metabolite findings requiring confirmation in larger studies.