Lactobacillus fermentum (MTCC-5898) based fermented whey renders prophylactic action against colitis by strengthening the gut barrier function and maintaining immune homeostasis

Abstract

Nutritional intervention using probiotic fermented dairy product has emerged as a promising prophylactic strategy to curb inflammatory bowel diseases. Under present investigation, the potential of fermented whey prepared with probiotic Lactobacillus fermentum (LF:MTCC-5898) was investigated on dextran sodium sulfate (DSS) induced impaired intestinal barrier function in mice. Probiotic fermented whey (PFW) consumption improved the symptoms of colitis-associated with intestinal inflammation by significantly (p < 0.01) diminishing the percent loss in body weight, disease activity index and spleen index with improved colon length besides hematological and histopathological score. Likewise, pre-treatment with PFW improved the barrier integrity (p < 0.01) in contrast to leaky condition induced by DSS administration which increased the FITC-dextran permeability across gut epithelium. PFW consumption also provided the gut immune protection through significantly increased (p < 0.05) TLR-2 expression and stimulated T-regulatory response by producing TGF-β (p < 0.01) and, potently suppressed (p < 0.01) inflammatory response (TNF-α, IL-4 and C-reactive protein). Further, PFW intake significantly enhanced (p < 0.05) immunoglobulin (sIgA) secretion and concomitantly restored the Occludin, ZO-1 (p < 0.01) and Claudin-1(p < 0.05) transcriptional expression as compared to colitis mice. Additionally, immune-fluorescence further established the presence of intact actin cytoskeleton and tight junction proteins (claudin-1, occludin and ZO-1) after PFW consumption. Thus, PFW rectified the impaired and leaky barrier junctions not only through modulation of transcriptional expression of tight junction genes but also with reduced secretion of inflammatory mediators and helped in ameliorating the colitis. Hence, probiotic fermented whey prepared with L.fermentum (MTCC-5898) could be used as potential prophylactic functional food in the prevention of gut ailments.

Keywords: Fermented whey; Gut-barrier integrity; Immunomodulation; Probiotics; Ulcerative colitis.