Objective To investigate the effect of dandelion polysaccharide (DP) on lipid metabolism disorder in liver and gut microbiota structure in high-fat diet-induced obese mice. Methods A total of 40 SPF male C57BL/6J mice were randomly divided into control group, model group, orlistat (10 mg/kg) group, DP low-, high-dose (200, 400 mg/kg) groups, with eight mice in each group. Mice were fed with high-fat diet to establish an obesity model, and the model was simultaneously administered with ig for eight weeks. After the end of administration, mice were euthanized by removing their eyeballs and collecting blood. Serum was collected to measure the levels of total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C); Hematoxylin-eosin (HE) staining and Oil red O staining were used to observe the pathological changes of liver and epididymal fat in mice; qRT-PCR was used to detect the expressions of lipid metabolism related genes [carnitine palmitoyltransferase 1 (CPT-1), cytochrome P450 family 7 subfamily A member 1 (CYP7A1), peroxisome proliferator-activated receptor α (PPARα), fatty acid synthase (FAS), peroxisome proliferator-activated receptor γ (PPARγ), stearoyl-CoA desaturase 1 (SCD-1), hormone-sensitive lipase (HSL), adipose triglyceride lipase (ATGL)] in liver tissue; Feces were collected from each group of mice for microbiome sequencing. Results Compared with control group, the body weight, epididymal fat index, and levels of TC, TG, LDL-C in serum of mice in model group were significantly increased (P < 0.01, 0.001), HDL-C level were significantly decreased (P < 0.01). The structure of liver cells was damaged, the intercellular space was unclear, the arrangement of hepatic cords was significantly disordered, the area of vacuoles and the number of lipid droplets were significantly increased (P < 0.001), and the volume of epididymal fat cells was significantly increased with varying cell shapes and sizes. The expression levels of fat generation related genes FAS, PPARγ and SCD-1 mRNA were significantly increased (P < 0.01), while the expression levels of fat breakdown related genes HSL and ATGL mRNA were significantly decreased (P < 0.01). Compared with model group, DP low-, high-dose groups and orlistat group all reduced the body weight and epididymal fat index of obese mice to varying degrees, and improved the histopathological morphology of liver tissue and epididymal fat. The expression levels of fat synthesis related genes FAS, PPARγ and SCD-1 were significantly reduced in DP high dose group (P < 0.01), while the expression levels of fat breakdown and oxidation related genes HSL, ATGL, CTP-1, CYP7A1, PPARα mRNA were significantly increased (P < 0.01). Meanwhile, DP regulated the species composition of gut microbiota in obese mice to a certain extent, significantly increased the relative abundance of Blautia, s_unclassified_g_Lachnospiraceae_NK4A136_group, Lachnospiraceae_bacterium_28-4 and Helicobacter rodentium, decreased the relative abundance of Erysipelatoclostridium and Ruminococcus_torques_group, and their dominant strains were positively correlated with fat oxidation and decomposition genes HSL, ATGL, CTP-1, CYP7A1 and PPARα, and negatively correlated with fat synthesis genes FAS, PPARγ and SCD-1. Conclusion DP could significantly reduce the body weight of obese mice induced by a high-fat diet. The mechanism may be related to regulating beneficial bacteria to promote fat oxidation and decomposition and inhibit fat synthesis.

dandelion polysaccharide  /  obesity  /  gut microbiota  /  lipid metabolism  /  fat oxidation and decomposition  /  fat synthesis  /  beneficial bacteria