Nier Anika, Engstler Anna Janina, Maier Ina Barbara, Bergheim Ina
Department of Nutritional Sciences, Molecular Nutritional Science, University of Vienna, Vienna, Austria.
Institute of Nutrition, SD Model Systems of Molecular Nutrition, Friedrich-Schiller University Jena, Jena, Germany.
PLoS One. 2017 Sep 7;12(9):e0183282. doi: 10.1371/journal.pone.0183282. eCollection 2017.
BACKGROUND & AIMS: Recent studies have shown that patients with manifest non-alcoholic fatty liver disease (NAFLD), e.g. steatosis grade 3 or steatohepatitis with or without beginning fibrosis frequently show altered fecal microbiota composition and elevated bacterial endotoxin levels. However, if these alterations are signs of a progressing disease or are already found in initial disease stages has not yet been clarified.
Twenty children with simple steatosis (grade 1) diagnosed by ultrasound and 29 normal weight healthy control children (age <10 years) were included in the study (mean age 7.6 ± 1.1 years). Metabolic parameters, markers of intestinal barrier function and inflammation were determined.
Activity of alanine aminotransferase, concentrations of some markers of inflammation and insulin resistance were significantly higher in plasma of NAFLD children than in controls. When compared to controls, plasma bacterial endotoxin and lipopolysaccharide-binding protein (LBP) levels were significantly higher in NAFLD children (+50% and +24%, respectively), while soluble CD14 serum and D-lactate plasma levels as well as the prevalence of small intestinal bacterial overgrowth did not differ between groups. Plasma endotoxin and LBP levels were positive associated with proinflammatory markers like plasminogen activator inhibitor-1, c-reactive protein, interleukin-6 and leptin while no associations with markers of insulin resistance were found.
Taken together, our results indicate that even in juvenile patients with early stages of NAFLD e.g. simple steatosis grade 1, plasma endotoxin concentrations are already elevated further suggesting that intestinal barrier dysfunction might be present already in the initial phases of the disease.
近期研究表明,患有明显非酒精性脂肪性肝病(NAFLD)的患者,如3级脂肪变性或伴有或不伴有早期纤维化的脂肪性肝炎患者,其粪便微生物群组成经常发生改变,细菌内毒素水平升高。然而,这些改变是疾病进展的迹象还是在疾病初始阶段就已出现,目前尚未明确。
本研究纳入了20名经超声诊断为单纯性脂肪变性(1级)的儿童以及29名体重正常的健康对照儿童(年龄<10岁)(平均年龄7.6±1.1岁)。测定了代谢参数、肠道屏障功能和炎症标志物。
NAFLD儿童血浆中丙氨酸转氨酶活性、一些炎症标志物和胰岛素抵抗标志物的浓度显著高于对照组。与对照组相比,NAFLD儿童血浆细菌内毒素和脂多糖结合蛋白(LBP)水平显著升高(分别升高50%和24%),而可溶性CD14血清和D-乳酸血浆水平以及小肠细菌过度生长的发生率在两组之间没有差异。血浆内毒素和LBP水平与纤溶酶原激活物抑制剂-1、C反应蛋白、白细胞介素-6和瘦素等促炎标志物呈正相关,而与胰岛素抵抗标志物无相关性。
综上所述,我们的结果表明,即使在患有NAFLD早期阶段(如单纯性1级脂肪变性)的青少年患者中,血浆内毒素浓度也已升高,这进一步表明肠道屏障功能障碍可能在疾病的初始阶段就已存在。