Project description:The C57BL/6J mouse model develops obesity and pre-diabetes when fed a high-fat diet. In this experiment, DNA methylation was assessed globally at specific CpG sites in liver tissue from mice receiving high-fat diet (45E% from fat) for 13 weeks (Control) or high-fat diet supplemented with 20% (w/w) of freeze-dried lingonberries (n=4). Our findings show that lingonberries prevent development of high-fat induced obesity, hepatic steatosis and low-grade inflammation, and the DNA was hypermethylated in mice receiving lingonberries compared to control. Genome wide hepatic DNA methylation comparison between mice fed high-fat diet with or without a lingonberry supplement (n=4/group).
Project description:Metabolic disorders, such as obesity and type 2 diabetes, are major public health concerns worldwide. Dietary interventions, such as tea consumption, have been suggested as an effective strategy to prevent and treat metabolic disorders. White adipose tissue, as the main energy storage organ in mammals, plays a critical role in the regulation of whole-body metabolism. Recent studies have shown that the microenvironmental cell composition and metabolic network of white adipose tissue can be modulated by dietary factors, including tea consumption. However, the underlying mechanisms and the effects of tea consumption on white adipose tissue in the context of high-fat diet-induced metabolic disorders are not fully understood. Therefore, this study aimed to investigate the effects of tea consumption on the microenvironmental cell composition and metabolic network of white adipose tissue in high-fat diet-fed mice.
Project description:Germfree (GF) mice have been used as a model to study the contribution of the intestinal microbiota to metabolic energy balance of the host. Despite a wealth of knowledge accumulated since the 1940’s, the response of GF mice to a high fat diet is largely unknown. In the present study, we compared the metabolic consequences of a high fat (HF) diet on GF and conventional (Conv) C57BL/6J mice. As expected, Conv mice developed obesity and glucose intolerance with a HF diet. In contrast, GF mice remained lean and resisted the HF diet-induced insulin resistance. The anti-obesity phenotype of GF/HF mice was accompanied by reduced caloric intake, diminished food efficiency, and excessive fecal lipid excretion contributed to the reduced food efficiency. In addition, HF diet-induced hypercholesterolemia was ameliorated, which was partially due to an increase in fecal cholesterol excretion. However, hepatic cholesterols were increased in GF/HF mice. Elevated nuclear SREBP2 proteins and the up-regulation of cholesterol biosynthesis genes support the increased liver cholesterol biosynthesis in GF/HF mice. The resistance to HF diet-induced metabolic abnormalities in GF mice was also associated with a reduced immune response, indicated by low plasma pro-inflammatory and anti-inflammatory markers. These data suggest that the gut microbiota of Conv mice contributes to HF diet-induced obesity, insulin resistance, dyslipidemia and hepatic steatosis in mice. Thus, results of the present study describe the metabolic responses of GF mice to a HF diet and further our understandings of the relationship between the gut microbiota and the host. Germfree and conventional C57BL/6J mice were fed with a high fat diet for 11 weeks. Then, all mice were sacrified under 10-h food deprevation, and liver samples of germfree (n=14) and conventional (n=16) were examined.