Effects Of Compound Dark Tea On Obesity And Glucose And Lipid Metabolism In High-fat Diet Mice And Its Mechanism

In this study,the C57BL/6J experimental mice were used as animal models to explore the effects of compound dark tea on growth performance,feed intake,blood glucose,blood lipids and molecular mechanisms induced by high-fat diet,and to comprehensively evaluate the biological functions of compound dark tea.In the experiment,36 C57/BL6 J mice with similar body weight were selected and set as blank control group(ND),high-fat diet model group(HFD),compound dark tea 6mg/ml(HL),compound dark tea 12mg/ml(HH)Four treatment groups,3 replicates per treatment,3 mice per replicate,and a total experimental period of 18 w.(1)The effect of compound dark tea on its growth performance was evaluated by measuring the body weight line chart,terminal body weight,body fat rate and average daily feed intake of mice.The study found that there was no significant difference in feed intake among the experimental groups.Differences,the high-fat diet group successfully established the model,and its body weight and body fat rate were extremely significantly higher than those of the ND group(P>0.01),and the compound dark tea experimental group significantly reduced the high-fat diet-induced weight gain and body fat rate.increased(P<0.01).The compound dark tea experimental group significantly improved high-fat diet-induced abnormal fasting blood glucose and impaired glucose tolerance;compound dark tea improved the growth performance and glucose metabolism disorder of mice.(2)To explore the effect of compound black tea on blood lipid content in mice by measuring blood lipid-related indicators(TC,TG,HDL-C,LDL-C)in mouse serum.Studies have shown that high-fat diet can significantly increase the contents of TC,TG,LDL-C and HDL-C in serum,and the compound dark tea experimental group significantly reduced the hyperlipidemia induced by high-fat diet.By measuring the contents of TC,TG and free fatty acid(FFA)in the liver tissue of mice,the experimental results showed that the TC and TG in the liver tissue of the high-fat diet group were significantly higher than those of the ND group,and the content of FFA was also significantly higher than that of the ND group,but there was no significant difference.The dark tea experimental groups all had a significant reducing effect on the accumulation of TC and TG in liver tissue,and also had a certain tendency to reduce the accumulation of FFA.The liver and kidney function-related indicators(ALT,AST,etc.)in the serum of the mice were measured.The experimental results showed that the contents of AST and ALP in the HFD group were significantly increased,which may indicate abnormal liver function and liver damage.The content of CREA in HFD group was significantly higher than that in ND group,and UA was higher than that in ND group.The results indicated that high-fat diet had adverse effects on renal protein utilization and renal function;AST and ALP in compound dark tea experimental group(HL and HH)were significantly lower than those in ND group.In the HFD group,CREA was also significantly lower than that in the HFD group,and the UA content showed a decreasing trend,suggesting that long-term drinking of compound dark tea has a potential protective effect on liver and kidney function damage induced by high-fat diet.(3)The pathological observation was carried out by H&E staining and UCP1 immunohistochemistry on brown adipose tissue,H&E staining on white adipose tissue,and HE staining and Oil Red O staining on liver tissue to explore the effect of compound black tea on lipid deposition in mouse liver.Impact.From the experimental results,the vacuoles in brown adipose tissue and white adipose tissue of mice in the high-fat diet group increased,the volume increased and the shape was irregular.The positive expression of UCP1 in brown adipocytes in the HFD group was significantly lower than that in the ND group;long-term drinking of compound black The adipocyte morphology of mice in the experimental group of tea was significantly improved and resistant to high-fat diet-induced brown fat "whitening".The results of HE staining showed that the fat vacuoles in the hepatocytes of the HFD group were significantly increased and enlarged,the morphology of the hepatocytes was changed,and the structure was destroyed.Oil red staining results have the same trend as H&E staining results.This indicated that prolonged high-fat diet resulted in massive deposition of lipids in hepatocytes,and consumption of complex dark tea while consuming a high-fat diet significantly reduced lipid deposition in hepatocytes.(4)By measuring brown adipose tissue and white adipose tissue for brown fat "whitening",white fat "browning" and the expression of target genes related to lipid synthesis and decomposition in liver tissue to explore the effect of compound dark tea on obesity,lipid Molecular Mechanisms of Metabolism.The results showed that the key characteristic genes of brown fat UCP1,PGC-1α,PPARγ,PRDM16 and other related target genes were significantly reduced under high-fat diet induction,which further clarified the weight gain of mice in high-fat diet group from the mechanism level.,Increased body fat rate and abnormal glucose and lipid metabolism.Under the action of compound dark tea,the expression of key characteristic genes of brown fat UCP1,PGC-1α,PPARγ,PRDM16,and CTP1 in HL and HH groups were significantly up-regulated compared with HFD group;The reasons for the significant reduction in body weight gain,the significant decrease in body fat rate,and the significant improvement in abnormal glucose and lipid metabolism in mice treated with compound dark tea.Compared with the ND group,the expression levels of UCP1,PGC-1α,PPARγ,FGF21,and Cidea,the key characteristic genes of subcutaneous inguinal fat "browning" in high-fat diet mice were significantly down-regulated,which indicated that highfat diet would hinder the growth of mice.The "browning" of white fat reduces its adaptive thermogenesis ability,and the long-term drinking of compound dark tea in mice can promote the expression levels of UCP1 and other genes related to fat "browning" to be significantly or significantly up-regulated.Therefore,compound dark tea has the potential to prevent obesity,improve insulin resistance,impaired glucose tolerance and other related metabolic diseases by promoting the molecular mechanism of "browning" of white fat.This study also explored the expression of genes related to lipid synthesis and decomposition in the liver.The expression of the target gene ATGL related to lipid decomposition in the liver under high-fat diet was significantly lower than that in the ND group.The expression of the ATGL gene was extremely significantly increased,thereby enhancing the ability of liver fat breakdown and extremely significantly improving the excessive accumulation of hepatic lipids induced by a high-fat diet.At the same time,the expression of liver lipid synthesis-related target genes SREBP-1C,FAS,and ACC2 under high-fat diet was significantly or significantly increased compared with ND group,and the expression of SREBP-1C,FAS and ACC2 in compound dark tea experimental group The level was extremely significant or significantly lower than that of the HFD group;this further indicated that long-term consumption of compound dark tea could improve the lipid oversynthesis and hepatic lipid deposition induced by high-fat diet.In conclusion,this study confirms that compound dark tea has the effect of reducing fat and weight loss,lowering blood sugar,the mechanism is achieved by regulating brown fat thermogenesis(UCP1,Nrf2),white fat browning(UCP1,PPARγ,PGC-1α),and hepatic lipid metabolism(ATGL,FAS,SREBP1-C).