L.CASEI CRL 431 AND ITS CELLULAR WALL HAS EFFECT ON THE THYMUS FUNCTIONALLITY IN A MICE OBESE MODEL

BALCELLS, FLORENCIA; VELEZ EVA; CAZORLA, SILVIA INES; PERDIGÓN, GABRIELA; MALDONADO GALDEANO CAROLINA

Buenos Aires

Congreso; Reunión Conjunta de Sociedades de BioCiencias; 2017

Aim: to study the effect of L. casei 431 and/or its cell wall on the thymus restoration in obese mice.Five weeks old BALB/c mice were divided into 2 groups: Normal Control (NC) that received a conventional balanced diet and water, Obese Control (OC) fed a high fat diet (HFD). NC and OC were divided into sub-groups: N+Probiotic (NP) and O+Probiotic (OP) who received probiotic strain suspension for 12 weeks.Body weight was determined 3 times per week. Animals were sacrificed at 12 weeks. The samples were thymus (T) for histology and T cells analyses, small intestinal fluid (IF) for cytokines determination (IL-6, IFNγ and IL-10), large intestine for microbiota studies. Cytokines were also determined in the supernatant of Thymus, peritoneal macrophages (PM) and spleen (SM) cultures treated with whole bacteria (B) or its cell wall (W).Results: OP reached peak body weight at week 9 and decreased at week 10 reaching to NC values and was maintained until end of the study. In relation body weight/thymus OC showed significantly higher values, probiotic supplementation decreases this relation. OC showed enterobacteria and total anaerobes population increased, and lactobacilli decreased. Higher values of lactobacilli were showed in OP. The immune cells in thymus, CD8+ and CD4+/CD8+ population in OL increased significantly respect to OC (CD8+: OC=13,5% ±1,5 OL=21,5%±12,8; CD4+/CD8+: OC=8,6%±2,9 OL=12,6% ±4,9). Cytokine in cellular cultures and IF showed IFNγ and IL-10 decrease in OC respect to NC, probiotic treatment increases significantly these values. IL-6 values increased in the supernatant of MP and Thymus of OC and in the IF. These values decreased with probiotic or cell wall addition. Both probiotic and its cell wall treatment were effective on the thymus weight and on T cells recovery during HFD, regulating the cytokine levels. At the intestinal levels probiotic supplementation ameliorated the inflammatory effect observed in obese mice.