Effects of lactic acid bacteria on amelioration of inflammatory response and dextran sodium sulfate-induced colitis

• Main Authors: Yu-Chen Wu, 吳羽宸
• Other Authors: Ying-Chieh Tsai
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/zjy9b7

碩士 === 國立陽明大學 === 生化暨分子生物研究所 === 102 === Breast milk was viewed as sterile, but many studies have found that microorganisms present in the milk, which contains several species of lactic acid bacteria (LAB). There are evidences that LAB has anti-inflammatory effects, studies also points out that human milk bacteria has a positive effect on the health of lactating mothers and babies. It makes human milk bacteria as the new target of probiotics development. This study uses dextran sodium sulfate (DSS) induced ulcerative colitis animal model to evaluate the anti-inflammatory effects of human milk bacteria on intestinal inflammation. To explore whether human milk bacteria could survive in the stressful environment of gastrointestinal tract and the ability of intestinal colonization, we use yeast agglutination test, extracellular polysaccharides forming test, acid, bile salt and phenol tolerance and biofilm formation test. Further, we use human intestinal epithelial cell line (Caco-2), mouse macrophage cell line (RAW 264.7) and human peripheral blood mononuclear cells (hPBMCs) to assess the anti-inflammatory potential of human milk bacteria. Five LABs thus stand out above the rest, and then five candidate LABs were compared the effect by oral administration on animal model of ulcerative colitis. Results showed that BMG1-5 have effects on alleviation of ulcerative colitis symptoms, including reduce fecal occult blood, decrease colon shortening. We evaluate the anti-inflammatory effects between alive and heat-killed BMG1-5. Histological analysis showed that BMG1-5 protect colonic wall integrity and decrease neutrophil infiltration. And the concentration of pro-inflammatory cytokines in colon tissue are reduced by BMG1-5. According to these experimental results, BMG1-5 significant ameliorate DSS-induced ulcerative colitis symptoms in mice. Thus, BMG1-5 could be expected as a supplementary agent to ulcerative colitis patient.