探究了四株益生菌对非酒精性脂肪性肝病（Nonalcoholic Fatty Liver Disease，NAFLD）的改善作用。30只小鼠随机分为正常组（N）、高脂饮食（HFD）模型组（M）及益生菌干预组四组：植物乳杆菌LP45（Lactobacillus plantarum，LP）、嗜酸乳杆菌La28 （Lactobacillus acidophilus，La）、鼠李糖乳杆菌LR519（Lactobacillus rhamnosus，LR）和乳双歧杆菌BAL531（Bifidobacteriumlactis，Bal）。正常组给予常规饲料喂养，其它组给予HFD喂养；同时益生菌组每天给予对应菌液灌胃21 d，对照组给等体量生理盐水；期间监测小鼠体质量和摄食量。检测内脏脂肪、肝脏生化指标、组织病理和炎症因子表达水平。与N组相比，M组摄食量、体质量及内脏脂肪均显著增加，高达8.74 g/d、33.30 g、0.71 g。较于M组，益生菌干预组小鼠的摄食量和内脏脂肪均明显降低，Bal、La、LR和LP组摄食量分别为6.97、6.91、5.94和6.59 g/d；内脏脂肪0.41、0.40、0.27和0.36 g；ALT、CHO、TG和MDA水平也显著下降；肝脂肪变性明显缓解；炎症因子ELF3和TNF-α的mRNA及IL-6的蛋白表达水平显著降低（P<0.05）。体外，四株益生菌也表现出一定抗氧化和降脂活性，其中Bal抗氧化活性最高，达16.81%；La降脂活性最高，为46.40%。Bal、La、LP、LR可有效改善小鼠的NAFLD，其机制至少部分归因于其降脂、抗炎、抗氧化和保肝等生物学活性。

This study aimed to explore the positive effects of four strains of probiotics on non-alcoholic fatty liver disease (NAFLD). Thirty mice were randomly divided into six groups: the normal control group (N), the high-fat diet (HFD)-model group (M), and four probiotic intervention groups (Lactobacillus plantarum [LP, 45], Lactobacillus acidophilus [La, 28], Lactobacillus rhamnosus LR, 519] and Bifidobacterium lactis [Bal, 531]). Group N was fed a regular diet, while the other groups were fed the HFD. Additionally, the probiotic intervention groups were fed by gavage daily with the corresponding bacteria solutions for 21 days. The control groups (N and M) received an equal volume of normal saline. Throughout this period, the body weight and food intake of the mice were monitored. Visceral fat, biochemical indices, histopathology, and inflammatory cytokine levels in the liver were examined. Compared to the N group, the M group demonstrated significant increases in food intake, body weight, and visceral fat, with values reaching 8.74 g/d, 33.30 g, and 0.71 g, respectively. The probiotic intervention groups showed marked reductions in food intake and visceral fat compared to the M group. Specifically, the food intake for the Bal, La, LR, and LP groups were 6.97, 6.91, 5.94, and 6.59 g/d, respectively, and the corresponding values for visceral fat were 0.41, 0.40, 0.27, and 0.36 g. Levels of alanine aminotransferase, cholesterol, triglycerides, and malondialdehyde significantly decreased. A notable alleviation in hepatic steatosis was observed. Furthermore, the levels of inflammatory cytokines (ELF3, TNF-α mRNA, and IL-6 protein) significantly decreased (P<0.05). The four probiotic strains also showed certain antioxidant and hypolipidemic activities in vitro. Notably, Bal had the highest antioxidant activity (16.81%) and La had the highest hypolipidemic activity (46.40%). The Bal, La, LP, and LR groups showed effective alleviation of NAFLD in mice. Our findings suggest that the hypolipidemic, anti-inflammatory, antioxidative, and liver-protective activities of the probiotic strains are at least partially responsible for the ameliorative effect on NAFLD.

湖北省老年胃肠癌精准防治临床医学研究中心开放基金项目（2022EGC-10）；宜昌市医疗卫生科研项目（A21-2-026；A17-301-24）；天然产物研究与利用湖北省重点实验室（三峡大学）开放基金项目（NPRD-2018012）