Synergistic Addition of Ligilactobacillus acidipiscis YJ5 to a Probiotic Consortium for Enhanced Alleviation of Loperamide-Induced Constipation in Mice

Probiotics have emerged as a promising therapeutic strategy for relieving constipation. The strategy of employing multi-strain probiotic combinations to achieve synergistic therapeutic effects is widely adopted in commercial applications. This study demonstrates that incorporating Ligilactobacillus acidipiscis YJ5 as a synergistic keystone strain into a base three-strain probiotic consortium (CP3-L) creates a potent low-dose formulation (CP4-L) with enhanced efficacy against loperamide-induced constipation in mice. Although the CP3-L consortium ( Lactiplantibacillus plantarum SYS1 and T34, Limosilactobacillus fermentum W1) itself outperformed its constituent single strains, the CP4-L consortium provided improvement in defecation parameters, intestinal barrier integrity, and inflammatory markers. It effectively restored interstitial cells of Cajal (ICC) markers (c‑Kit/SCF) to enhance intestinal motility, downregulated colonic aquaporins to increase fecal water content, and selectively modulated the gut microbiota to raise beneficial Bifidobacterium and fecal butyrate levels. These findings validate a mechanism-guided approach to probiotic consortium design, where functional complementarity between strains yields synergistic, multi-target anti-constipation activity at a reduced dosage.