Forsyth Christopher B, Farhadi Ashkan, Jakate Shriram M, Tang Yueming, Shaikh Maliha, Keshavarzian Ali
Department of Internal Medicine, Division of Digestive Diseases and Nutrition, and Rush University Medical Center, 1725 W. Harrison, Suite 206, Chicago, IL 60612, USA.
Alcohol. 2009 Mar;43(2):163-72. doi: 10.1016/j.alcohol.2008.12.009.
Because only 30% of alcoholics develop alcoholic liver disease (ALD), a factor other than heavy alcohol consumption must be involved in the development of alcohol-induced liver injury. Animal and human studies suggest that bacterial products, such as endotoxins, are the second key co-factors, and oxidant-mediated gut leakiness is one of the sources of endotoxemia. Probiotics have been used to prevent and treat diseases associated with gut-derived bacterial products and disorders associated with gut leakiness. Indeed, "probiotic"Lactobacillus rhamnosus has been successfully used to treat alcohol-induced liver injury in rats. However, the mechanism of action involved in the potential beneficial effects of L. rhamnosus in alcohol liver injury is not known. We hypothesized that probiotics could preserve normal barrier function in an animal model of ALD by preventing alcohol-induced oxidative stress and thus prevent the development of hyperpermeability and subsequent alcoholic steatohepatitis (ASH). Male Sprague-Dawley rats were gavaged with alcohol twice daily (8 gm/kg) for 10 weeks. In addition, alcoholic rats were also treated with once daily gavage of either 2.5 x 10(7) live L. rhamnosus Gorbach-Goldin (LGG) or vehicle (V). Intestinal permeability (baseline and at 10 weeks) was determined using a sugar bolus and GC analysis of urinary sugars. Intestinal and liver tissues were analyzed for markers of oxidative stress and inflammation. In addition, livers were assessed histologically for severity of ASH and total fat (steatosis). Alcohol+LGG (ALC+LGG)-fed rats had significantly (P< or =.05) less severe ASH than ALC+V-fed rats. L. rhamnosus Gorbach-Goldin also reduced alcohol-induced gut leakiness and significantly blunted alcohol-induced oxidative stress and inflammation in both intestine and the liver. L. rhamnosus Gorbach-Goldin probiotic gavage significantly ameliorated ASH in rats. This improvement was associated with reduced markers of intestinal and liver oxidative stress and inflammation and preserved gut barrier function. Our study provides a scientific rationale to test probiotics for treatment and/or prevention of alcoholic liver disease in man.
由于只有30%的酗酒者会发展为酒精性肝病(ALD),因此除大量饮酒外,必然有其他因素参与酒精性肝损伤的发生发展。动物和人体研究表明,细菌产物,如内毒素,是第二个关键的协同因素,而氧化应激介导的肠道通透性增加是内毒素血症的来源之一。益生菌已被用于预防和治疗与肠道来源细菌产物相关的疾病以及与肠道通透性增加相关的病症。事实上,“益生菌”鼠李糖乳杆菌已成功用于治疗大鼠酒精性肝损伤。然而,鼠李糖乳杆菌对酒精性肝损伤潜在有益作用的作用机制尚不清楚。我们推测,益生菌可以通过预防酒精诱导的氧化应激,在ALD动物模型中维持正常的屏障功能,从而预防通透性增加及随后的酒精性脂肪性肝炎(ASH)的发生。雄性Sprague-Dawley大鼠每天两次灌胃给予酒精(8克/千克),持续10周。此外,酒精喂养的大鼠还每天一次灌胃给予2.5×10⁷活的鼠李糖乳杆菌戈尔巴赫-戈尔丁株(LGG)或赋形剂(V)。使用糖丸和尿糖的气相色谱分析测定肠道通透性(基线和10周时)。分析肠道和肝脏组织中的氧化应激和炎症标志物。此外,对肝脏进行组织学评估,以确定ASH的严重程度和总脂肪(脂肪变性)。喂食酒精+LGG(ALC+LGG)的大鼠ASH严重程度明显低于喂食ALC+V的大鼠(P≤0.05)。鼠李糖乳杆菌戈尔巴赫-戈尔丁株还降低了酒精诱导的肠道通透性增加,并显著减轻了酒精诱导的肠道和肝脏氧化应激及炎症。鼠李糖乳杆菌戈尔巴赫-戈尔丁株益生菌灌胃显著改善了大鼠的ASH。这种改善与肠道和肝脏氧化应激及炎症标志物减少以及肠道屏障功能维持有关。我们的研究为在人类中测试益生菌治疗和/或预防酒精性肝病提供了科学依据。