Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Food Science & Nutritional Engineering, China Agricultural University, Beijing, P. R. China.
Food Funct. 2019 Jun 19;10(6):3368-3378. doi: 10.1039/c8fo01967c.
Gut microbiota has been identified as an important factor in the link between nutrient excess and obesity. The aim of this study was to confirm whether bovine α-lactalbumin hydrolysates (LAH) can ameliorate high-fat diet (HFD)-induced endotoxemia and systematic inflammation by modulating the structure of gut microbiota in mice. The results showed that LAH changed the overall structure of gut microbiota in HFD-induced obese mice. LAH increased the Bacteroidetes/Firmicutes ratios and the relative abundance of S24-7, Lachnospiraceae and Blautia. Spearman's correlation analysis revealed significant correlations between the alteration of gut microbiota and obesity-related indexes. LAH decreased the HFD-induced protein expression of G protein-coupled receptor 43 (GPR43) and 41 (GPR41) in the colon tissue. Besides, LAH inhibited the destruction of the gut barrier through the up-regulation of tight junction protein (zonulin/zonula occludens (ZO)-1 and occludin) expression and the decrease of toll-like receptor 4 (TLR4) protein expression in the colon tissue. LAH also significantly reduced the concentration of tumour cell necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in both serum and colon and decreased the level of lipopolysaccharides (LPS) in serum and feces, leading to reduced systematic inflammation and metabolic endotoxemia. In summary, LAH partly modulated the gut microbial composition and structure, and alleviated the obesity-associated inflammation. These findings shed light on bovine α-lactalbumin hydrolysate as a potential functional food ingredient to prevent obesity-related inflammation.
肠道微生物群已被确定为营养过剩与肥胖之间关联的重要因素。本研究旨在确认牛α-乳白蛋白水解物（LAH）是否通过调节高脂肪饮食（HFD）诱导肥胖小鼠的肠道微生物群结构来改善内毒素血症和全身炎症。结果表明，LAH 改变了 HFD 诱导肥胖小鼠肠道微生物群的整体结构。LAH 增加了拟杆菌门/厚壁菌门的比例和 S24-7、lachnospiraceae 和 Blautia 的相对丰度。Spearman 相关性分析显示，肠道微生物群的改变与肥胖相关指标之间存在显著相关性。LAH 降低了 HFD 诱导的结肠组织中 G 蛋白偶联受体 43（GPR43）和 41（GPR41）的蛋白表达。此外，LAH 通过上调紧密连接蛋白（zonulin/zonula occludens (ZO)-1 和 occludin）的表达和降低结肠组织中 toll 样受体 4（TLR4）蛋白的表达，抑制了肠道屏障的破坏。LAH 还显著降低了血清和结肠中肿瘤坏死因子-α（TNF-α）和白细胞介素-6（IL-6）的浓度，并降低了血清和粪便中脂多糖（LPS）的水平，从而减轻了全身炎症和代谢性内毒素血症。综上所述，LAH 部分调节了肠道微生物群落的组成和结构，并缓解了肥胖相关的炎症。这些发现为牛α-乳白蛋白水解物作为预防肥胖相关炎症的潜在功能性食品成分提供了依据。
