Effect of Yogurt With or Without Probiotic Addition on Body Composition Changes and Immune System in an Obese Model

Abstract

Yogurt is a dairy product made by milk fermented with Lactobacillus bulgaricus and Streptococcus thermophilus. Probiotic bacteria are added to conventional yogurt in order to boost benefits on the consumer health.In present work we studied in an obese mouse model the effect of the yogurt or probiotic yogurt supplementation to the diet on body weight, in biochemical parameters and in the thymus and intestinal immune system improvement. Adult mice received conventional balanced diet or a high-fat diet supplemented with milk, conventional yogurt or probiotic yogurt over 60 d. The body weight and biochemical parameters in serum (glucose, total LDL and HDL-cholesterol and triglycerides) were determined. Small intestine and thymus histology were analyzed. The changes in the gut microbiota, the possible translocation to internal organs and the levels of IgA and cytokines were also investigated. Probiotic yogurt was the most effective supplement for decreasing body weight and normalizing biochemical parameters in serum and in the improvement of small intestine and thymus histology. The gut microbiota showed increased bifidobacteria and recovered the balance of Enterobacteria population in obese mice given probiotic yogurt without translocation to internal organs, showing increases in IgA+ cells and cytokine production in gut.The present study demonstrated the safety and useful of yogurt consumption in obese host, benefiting mainly the innate mucosal immunity, biochemical parameters, intestine and thymus histology.These results allows advance in the research about the influence of functional foods on the thymus cells activity, which play a key role in the immune response.