Department of Gastroenterology, First Affiliated Hospital of China Medical University, 110001 Shenyang, Liaoning Province, China.
BMC Gastroenterol. 2013 Oct 20;13:151. doi: 10.1186/1471-230X-13-151.
This study aimed to investigate the mechanism of the probiotic VSL#3 in acute alcoholic intestinal injury, and evaluate the effect of VSL#3, glutamine,VSL#3+glutamine and heat-killed VSL#3 therapy in a rat model.
Six- to eight-week-old male wild-type rats were divided into seven groups. To establish the acute alcohol liver disease model, rats received three doses of corn starch dissolved in PBS/40% alcohol administered intra-gastrically every 12 hours. Treatment groups received an intra-gastric dose of VSL#3, Glutamine, heat-killed VSL#3, or VSL#3+Glutamine 30 minutes prior to alcohol administration. The placebo group was treated with PBS prior to alcohol administration. TNFα and endotoxin in plasma was measured by ELISA and Tachypleus Ameboctye Lysate assays, and electron microscopy, Western blotting, and reverse transcription polymerase chain reaction were used to identify the mechanisms of VSL#3 in the regulation of epithelial permeability.
First, compared with control group, endotoxin and TNFα in alcohol group was obviously high. At the same time, in VSL#3 group,the expression of endotoxin and TNFα obviously lower than the alcohol group. And the trends of the expression of tight junction proteins in these groups were reversed with the change of endotoxin and TNFα. Second, compared the groups of VSL#3 with glutamine,VSL#3+glutamine and heat-killed VSL#3,we found that both VSL#3 and heat-killed VSL#3, glutamine were as effective as VSL#3+glutamine in the treatment of acute alcohol liver disease, the expression of endotoxin and TNFα were lower than the alcohol group, and tight junction proteins were higher than the alcohol group whereas the expression of tight junction proteins were higher in VSL#3 + glutamine group than either agent alone, but have no significant difference.
We conclude that VSL#3 treatment can regulate the ecological balance of the gut microflora, preventing passage of endotoxin and other bacterial products from the gut lumen into the portal circulation and down-regulating the expression of TNFα, which could otherwise down-regulate the expression of tight junction proteins and increase epithelial permeability.
本研究旨在探讨益生菌 VSL#3 在急性酒精性肠损伤中的作用机制,并评估 VSL#3、谷氨酰胺、VSL#3+谷氨酰胺和热灭活 VSL#3 治疗在大鼠模型中的效果。
将 6-8 周龄雄性野生型大鼠分为 7 组。为了建立急性酒精性肝病模型,大鼠每 12 小时接受 3 次溶于 PBS/40%酒精的玉米淀粉的胃内给药。治疗组在给予酒精前 30 分钟接受胃内 VSL#3、谷氨酰胺、热灭活 VSL#3 或 VSL#3+谷氨酰胺的剂量。安慰剂组在给予酒精前接受 PBS 处理。通过 ELISA 和鲎变形细胞溶解物试验测定血浆中的 TNFα 和内毒素,通过电子显微镜、Western blot 和逆转录聚合酶链反应鉴定 VSL#3 调节上皮通透性的作用机制。
首先,与对照组相比,酒精组中的内毒素和 TNFα 明显升高。同时,在 VSL#3 组中,内毒素和 TNFα 的表达明显低于酒精组。这些组中紧密连接蛋白的表达趋势随着内毒素和 TNFα 的变化而逆转。其次,与 VSL#3 与谷氨酰胺、VSL#3+谷氨酰胺和热灭活 VSL#3 的组相比,我们发现 VSL#3 和热灭活 VSL#3 与谷氨酰胺一样有效治疗急性酒精性肝病,内毒素和 TNFα 的表达低于酒精组,紧密连接蛋白的表达高于酒精组,而 VSL#3+谷氨酰胺组的紧密连接蛋白表达高于任一单一药物,但无显著差异。
我们的结论是,VSL#3 治疗可以调节肠道微生物群落的生态平衡,防止内毒素和其他细菌产物从肠道腔转移到门静脉循环,并下调 TNFα 的表达,否则会下调紧密连接蛋白的表达并增加上皮通透性。