Prevention of intestinal inflammation and synovitis during Salmonella enterocolitis in mice fed with Lactobacillus casei fermented milk

NOTO LLANA; GARTNER, A; GIACOMODONATO MN; SARNACKI, SH; AYA CASTAÑEDA, MR; CERQUETTI MC

Congreso; XLVII Reunión Anual de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2011

We investigated inflammatory responses of intestine and knee joints in a mouse model for enterocolitis. Mice were inoculated orally with 20 mg of streptomycin and 24 hs later they received 103 CFU of a virulent strain of Salmonella Enteritidis by the same route. Salmonella was recovered from Peyer´s patches (PP) up to day 4 and from spleen up to day 14. Bacteria were neither recovered from knee joints nor from draining lymphnodes. Infected mice showed a significant increase in intestinal IL-17 and TNF-a, determined by qPCR. 21 days post-infection animals presented synovitis in the knee joints, suggesting that this model of Salmonella enterocolitis is suitable for studying reactive arthritis. We then tested the effect of probiotics in preventing the joint sequelae. Mice were fed with commercially-available Lactobacillus casei fermented milk for 7 days before infection. PP and spleen of mice pretreated with probiotics were less colonized with Salmonella, and for a shorter period. Probiotic feeding previous to Salmonella infection resulted in a significant decrease of gut inflammatory cytokines, compared to infected animals not receiving Lactobacillus. Our results showed that the model for enterocolitis might be useful for studying the pathogenesis of Salmonella-induced synovitis and that these sequelae were prevented in mice pretreated with fermented milk containing L. casei.