A comparative study of the preventative effects exerted by three probiotics,Bifidobacterium lactis,Lactobacillus caseiandLactobacillus acidophilus, in the TNBS model of rat colitis

Abstract

Aims: The intestinal anti‐inflammatory effects of three probiotics with immunomodulatory properties, Lactobacillus casei, Lactobacillus acidophilus and Bifidobacterium lactis, were evaluated and compared in the trinitrobenzenesulphonic acid (TNBS) model of rat colitis. Methods and Results: Colitis was induced in rats by intracolonic administration of 10 mg of TNBS dissolved in 0·25 ml of 50% ethanol. Each probiotic was administered orally (5 × 108 CFU suspended in 0·5 ml of skimmed milk) for 3 weeks, starting 2 weeks before the administration of TNBS. Colonic damage was evaluated histologically and biochemically 1 week after TNBS instillation. The results obtained revealed that all probiotics assayed showed intestinal anti‐inflammatory effects, macroscopically evidenced by a significant reduction in the colonic weight/length ratio. Only B. lactis showed a lower incidence of diarrhoea in comparison with untreated rats. Biochemically, all probiotics restored colonic glutathione levels, depleted as a consequence of the oxidative stress of the inflammatory process. Bifidobacterium lactis treatment reduced colonic tumour necrosis factor (TNF)‐α production, and inducible nitric oxide synthase (iNOS) and cyclo‐oxygenase‐2 (COX‐2) expression; L. acidophilus administration reduced colonic leukotriene B4 production and iNOS expression and L. casei intake was associated with a decrease in colonic COX‐2 expression. Conclusion: The three probiotics assayed have shown intestinal anti‐inflammatory activity in the TNBS model of rat colitis, although each probiotic shows its own anti‐inflammatory profile. Significance and Impact of the Study: These probiotics could be considered as potential adjuvants in the treatment of inflammatory bowel disease, although more studies are required in order to demonstrate their efficacy in humans.

Bifidobacterium bifidum reduces apoptosis in the intestinal epithelium in necrotizing enterocolitis

“…There have been only a few studies exploring the effect of different probiotics on COX-2 expression in intestinal cells or rat models of colitis. Both in vivo and in vitro studies show decreased COX-2 with probiotic treatment (28,34,35) except for Lactobacillus acidophilus, which significantly increased COX-2 expression in intestinal cells (34). This demonstrates how the effects of probiotics vary, and the protective mechanisms depend on each strain.…”

Lactobacillus Salivarius REN Inhibits Rat Oral Cancer Induced by 4-Nitroquioline 1-Oxide

“…These findings suggested that inhibition of COX-2 may be another mechanism to suppress the development of 4NQO-induced oral carcinogenesis. Several species of probiotics were also proven to reduce the inflammation response by downregulating the COX-2 expression in vivo (36,37). However, this mechanism had not been proven effective in cancer prevention.…”

Probiotics and immunity

“…However, downregulating the production of proinfl ammatory cytokines and other infl ammatory mediators seems to constitute important mechanisms for the partial amelioration of colitis seen with numerous LAB strains in various models. 48,[100][101][102] Of note, TNF-α blocking agents are also quite successful in the treatment of patients with CD.…”