Large Yellow Tea Extract Ameliorates Metabolic Syndrome by Suppressing Lipogenesis through SIRT6/SREBP1 Pathway and Modulating Microbiota in Leptin Receptor Knockout Rats

Abstract

Metabolic syndrome is a chronic metabolic disorder that has turned into a severe health problem worldwide. A previous study reported that large yellow tea exhibited better anti-diabetic and lipid-lowering effects than green tea. Nevertheless, the potential mechanisms are not yet understood. In this study, we examined the prevention effects and mechanisms of large yellow tea water extract (LWE) on metabolic syndrome using leptin receptor knockout (Lepr−/−) rats. Seven-week-old male Lepr−/− and wild type (WT) littermate rats were divided into Lepr−/− control group (KO) (n = 5), Lepr−/− with LWE-treated group (KL) (n = 5), WT control group (WT) (n = 6), and WT with LWE intervention group (WL) (n = 6). Then, the rats were administered water or LWE (700 mg/kg BW) daily by oral gavage for 24 weeks, respectively. The results showed that the administration of LWE significantly reduced the serum concentrations of random blood glucose, total cholesterol, triglyceride, and free fatty acids, and increased glucose tolerance in Lepr−/− rats. Moreover, LWE remarkably reduced hepatic lipid accumulation and alleviated fatty liver formation in Lepr−/− rats. A mechanistic study showed that LWE obviously activated SIRT6 and decreased the expression of key lipogenesis-related molecules SREBP1, FAS, and DGAT1 in the livers of Lepr−/− rats. Furthermore, LWE significantly improved microbiota dysbiosis via an increase in gut microbiota diversity and an abundance of the microbiota that produce short chain fatty acids (SCFAs), such as Ruminococcaceae, Faecalibaculum, Intestinimonas, and Alistipes. Finally, LWE supplementation increased the concentrations of SCFAs in the feces of Lepr−/− rats. These results revealed that LWE attenuated metabolic syndrome of Lepr−/− rats via the reduction of hepatic lipid synthesis through the SIRT6/SREBP1 pathway and the modulation of gut microbiota.

Large yellow tea polysaccharides ameliorate obesity-associated metabolic syndrome by promoting M2 polarization of adipose tissue macrophages

“…In this study, we exhibited that homogeneous LYT polysaccharides (LYPs) could prevent diet-induced obesity and metabolic syndrome via improving glucolipid homeostasis, increasing energy expenditure, modulating islet β-cell function, and reducing M1 polarization of ATMs and inflammatory responses in C57BL/6J mice. Consistent with the previous studies demonstrating the anti-obesity efficacy of LYT, 23,24 our results confirmed that the oral administration of LYPs remarkably reduced HFD-induced body weight gain and visceral fat mass. Obesity-related metabolic syndrome is accompanied by hyperglycemia, hyperlipidemia, and hyperinsulinemia.…”

“…Consistent with the previous studies demonstrating the anti-obesity efficacy of LYT, 23,24 our results confirmed that the oral administration of LYPs remarkably reduced HFD-induced body weight gain and visceral fat mass. Obesity-related metabolic syndrome is accompanied by hyperglycemia, hyperlipidemia, and hyperinsulinemia.…”

Integrating metabolite and transcriptome analysis revealed the different mechanisms of characteristic compound biosynthesis and transcriptional regulation in tea flowers

“…It is important to research new applications of tea flowers for improving the economic value thereof. Large-leaf yellow tea (LYT) is one kind of yellow-type tea which has multiple health benefits, such as alleviating alcoholic liver disease and inhibiting adipose tissue hypertrophy ( Xu et al., 2021 ; Wang et al., 2022 ; Wu et al., 2022 ). However, LYT is made from old tea leaves and stems, leading to poor aroma and flavor or being unpopular.…”

Gastrodia elata Blume extract improves high-fat diet-induced type 2 diabetes by regulating gut microbiota and bile acid profile

“…Consistent with this, a previous study showed that GEBE increased the abundance of Faecalibaculum and thereby ameliorated early atherosclerosis in mice (Liu et al, 2021). In addition, the abundance of Faecalibaculum was previously reported to be closely and negatively associated with characteristics of the metabolic syndrome (Wu et al, 2022a). Lactobacillus, a recognized probiotic, ameliorates glucose metabolism disorders and disturbances of the intestinal ecology in a rat model of T2D and reduces inflammation and the circulating concentration of lipopolysaccharide (El-Baz et al, 2021;Wu et al, 2022b).…”