State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China.
Food and Nutritional Science, School of Biological Science, University of Hong Kong, Pokfulam Road, Hong Kong, China.
J Dairy Sci. 2020 Apr;103(4):2969-2981. doi: 10.3168/jds.2019-17185. Epub 2020 Feb 12.
Enterococcus hirae WEHI01 is a potential probiotic strain isolated from a healthy Chinese infant. This strain has previously been characterized as having cholesterol-lowering potential and good dairy fermentation performance. In this study, we used rat models with obesity and type 2 diabetes mellitus (T2DM) induced by a high fat and sucrose diet and low-dose streptozotocin, respectively, and we evaluated the effect of E. hirae WEHI01 on glycolipid metabolism, glycolipid-related gene expression, organ histopathology, and intestinal flora changes in the 2 models. Our results showed that administration of 5.0 × 10 cfu of E. hirae WEHI01 for 4 wk decreased serum lipid levels and regulated glycolipid metabolism in the liver of obese rats. Following continuous administration of the same concentration of E. hirae WEHI01 to a T2DM rat model for another 5 wk, E. hirae WEHI01 improved glucose tolerance, recovered body weight loss, and led to significant decreases in tumor necrosis factor-α, IL-6, IL-10, and total bile acid in serum. We also found that E. hirae WEHI01 restored the morphology of the pancreas, kidney, and liver, and changed the composition of the gut microbiota (i.e., decreased the Shannon index, increased the Simpson index, and substantially increased the abundance of Lactobacillales). Combining the results for the obese model and the T2DM model, we speculated that beneficial effects of E. hirae WEHI01 on T2DM could be due to (1) a significant increase in PPARA expression and a tendency for increased CYP7A1 expression in the liver of obese rats, promoting the conversion of cholesterol into bile acid and reducing serum total bile acid levels in T2DM model rats; or (2) a change in gut microbial diversity, especially elevated Lactobacillales abundance, which reduced the total bile acid in T2DM model rats. These results demonstrated that E. hirae WEHI01 has the potential to ameliorate type 2 diabetes in rats and provide a promising rationale for further research into the prevention and treatment of T2DM.
屎肠球菌 WEHI01 是从健康中国婴儿中分离出来的一种有潜力的益生菌株。该菌株先前被鉴定具有降低胆固醇的潜力和良好的乳制品发酵性能。在这项研究中，我们使用高脂肪和蔗糖饮食以及低剂量链脲佐菌素分别诱导肥胖和 2 型糖尿病（T2DM）的大鼠模型，评估了屎肠球菌 WEHI01 对糖脂代谢、糖脂相关基因表达、器官组织病理学和 2 种模型肠道菌群变化的影响。结果显示，5.0×10cfu 的屎肠球菌 WEHI01 连续给药 4 周可降低肥胖大鼠血清脂质水平并调节肝脏糖脂代谢。连续给予相同浓度的屎肠球菌 WEHI01 5 周后，可改善 2 型糖尿病大鼠的葡萄糖耐量，恢复体重减轻，并显著降低血清肿瘤坏死因子-α、IL-6、IL-10 和总胆汁酸。我们还发现屎肠球菌 WEHI01 恢复了胰腺、肾脏和肝脏的形态，并改变了肠道微生物群的组成（即降低 Shannon 指数，增加 Simpson 指数，并显著增加乳杆菌目丰度）。综合肥胖模型和 T2DM 模型的结果，我们推测屎肠球菌 WEHI01 对 T2DM 的有益作用可能归因于（1）肥胖大鼠肝脏中 PPARA 表达显著增加，CYP7A1 表达有增加趋势，促进胆固醇转化为胆汁酸，降低 T2DM 模型大鼠血清总胆汁酸水平；或（2）肠道微生物多样性发生变化，特别是乳杆菌目丰度升高，降低 T2DM 模型大鼠的总胆汁酸。这些结果表明屎肠球菌 WEHI01 具有改善大鼠 2 型糖尿病的潜力，为进一步研究 2 型糖尿病的预防和治疗提供了有希望的依据。
