[Prophylactic effect of Lactobacillus GG in animal colitis and its effect on cytokine secretion and mucin gene expressions]

Abstract

Background/aims: Lactobacillus rhamnosus GG (LGG) has been used in acute colitis treatment. However, it is unclear whether the LGG prevents chronic colitis. The aim of this study was to examine the prophylactic effect of LGG on animal colitis, cytokine secretion, and mucin gene expression.

Methods: BALB/c mice (n=64) were exposed to 5% dextran sulfate sodium (DSS) for 7 days followed by 10 days recovery period and repeatedly exposed for 4 days. Then, the mice were devided into three group; group of oral LGG adminstration throughout the recovery and repeated colitis period; PBS group of PBS administration; control group. Colon length, histologic score, tumor necrosis factor-alpha (TNF-alpha), interleukin-10 (IL-10) levels, mucin gene expressions were determined at each period.

Results: In acute colitis period, the LGG group showed higher levels of disease activity index (DAI), histologic score, TNF-alpha, IL-10, but shorter colon length, lower levels of mucin gene expressions than the control group. However, in repeated colitis period, the LGG group showed markedly lower levels of DAI and IL-10 but significantly longer colon length than PBS group (p<0.05). There was no difference in the mucin gene expression.

Conclusions: These results suggest that LGG prevents chronic murine colitis. It may be associated with cytokine modulation and competitive inhibition of pathogenic bacteria. However, it may not be related with gene expression.