相对于高脂饮食的小鼠，每只小鼠每天口服1×109 CFU剂量的BL21可使其体重减轻16.9％，并显着降低血清中的总胆固醇、甘油三酸酯和低密度脂蛋白胆固醇水平。BL21改善了肝细胞中的脂肪空泡化和附睾脂肪积聚。BL21还降低了厚壁菌/拟杆菌比例，调节了甘油磷脂中的肝脏重构，并降低了d-色氨酸的水平。首次发现了产丁酸盐的罗斯氏菌（Roseburia）与细胞膜成分磷脂酰丝氨酸呈正相关。因此，BL21可以通过重整肠道菌群和甘油磷脂代谢来预防小鼠肥胖。BL21可作为一种用于控制体重的前景广阔的膳食补充剂。
Bifidobacterium longum subsp. longum Remodeled Roseburia and Phosphatidylserine Levels and Ameliorated Intestinal Disorders and liver metabolic Abnormalities Induced by High-Fat Diet
Tao Wu1, Mengzhen Sun1, Rui Liu1, Wenjie Sui1, Jiaojiao Zhang2, Jinjin Yin1,*, Shuguang Fang3, Jianguo Zhu3, Min Zhang1,4,*
1 State Key Laboratory of Food Nutrition and Safety, Tianjin University of Science & Technology, Tianjin 300457, China
2 Department of Clinical Sciences, Faculty of Medicine, Università Politecnicadelle Marche, Ancona 60131, Italy
3 Jiangsu Wecare Biotechnology Co., LTD, Suzhou, Jiangsu 215200, China
4 Tianjin Agricultural University, Tianjin 300384, PR China
Bifidobacterium longum is considered as a potential supplement in antiobesity treatment; however, the underlying molecular mechanism has rarely been studied. To understand the contributions of B. longum subsp. Longum (BL21) in the prevention of obesity, we investigated alterations in the liver metabonomic phenotype and gut microbiota by ultraperformance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry and 16S ribosomal RNA gene sequencing in C57BL/6J male mice orally administered with BL21 for 8 weeks [high-fat diet (HFD)]. BL21 at 1 × 109 CFU·day-1 per mouse reduced the weight of mice by 16.9% relative to that of the mice fed with HFD and significantly lowered the serum levels of total cholesterol, triglycerides, and low-density lipoprotein cholesterol. BL21 also ameliorated fat vacuolization in liver cells and epididymal fat accumulation. BL21 also lowered the Firmicutes/Bacteroidetes ratio, regulated liver remodeling in glycerophospholipids, and alleviated the levels of d-tryptophan. A positive correlation between the butyrate-producing strain Roseburia and the cell membrane component phosphatidylserine was found for the first time. Thus, BL21 can potentially prevent mice from being obese by rebalancing the gut microbiota and glycerophospholipid metabolism. BL21 can be a promising dietary supplement for weight control.
