Effect of probiotic bacteria Lactobacillus paracasei subsp. paracasei on the development of acute colitis in BALB/c mice.

Inflammatory bowel disease - ulcerative colitis and Crohn's disease - are chronic relapsing intestinal disorders of unknown etiology. Acute ulcerative colitis was induced in BALB/c mice by 3 % dextran sulfate sodium (DSS) administrated in drinking water for 5 days. The effect of Lactobacillus paracasei subsp. paracasei RL14-P, a bacterium with potential probiotic influence, on the development of inflammation was evaluated. Lactobacillus was administrated intragastrically to mice on days 1, 4 and 8 and the administration continued for next 5 days during DSS treatment. Control groups received instead of lactobacillus MRSC medium or phosphate-buffered saline according to the same schedule. Clinical symptoms such as diarrhoea, rectal bleeding and loss in body weight were evaluated daily. Cytokine secretion (IL-6, IL-10 and TNF-α) was determined in supernatants of 48 h cultivated splenocytes, mesenteric lymph node lymphocytes and colon pieces by ELISA. The impairment of colon descendens was evaluated histologically. Lactobacillus paracasei subsp. paracasei RL14-P administrated mice remained healthy without signs of the intestinal inflammation. We did not find the shortening of colon (a sign of inflammed intestine) in lactobacillus-treated mice. We observed that administration of probiotic bacteria..