Protective and ameliorative effects of maté (Ilex paraguariensis) on metabolic syndrome in TSOD mice

Yerba maté (mate) tea, a herbal tea prepared from the leaves of Ilex paraguariensis, is widely consumed in southern Latin America, and is gaining popularity worldwide. We investigated effects of an aqueous extract of mate on metabolic syndrome features in a metabolic syndrome model Tsumura Suzuki obese diabetic (TSOD) mouse. Oral administration of mate (100 mg/kg) for 7 weeks induced significant decreases in body weight, body mass index, and food intake in TSOD. It significantly decreased the hyperglycemia by reducing fasting blood glucose level, and increasing glucose uptake in glucose tolerance test. It also showed significant improvement in insulin sensitivity by increasing glucose uptake in insulin tolerance test, increasing quantitative insulin sensitivity check index, and decreasing homeostasis model assessment of insulin resistance index. The results also showed significant effects of mate on hyperlipidemia by decreasing blood levels of triglycerides, non-esterified fatty acids, and total cholesterol. Moreover, mate significantly improved adiponectin (AD) level, and exhibited significant reduction in white adipose tissue weight, and adiposity index in TSOD. It also showed significant ameliorative effects on TSOD histopathology, by reducing adipocytes proliferation, and improving hepatic steatosis. Furthermore, mate administration induced a dose-dependent delay in gastric emptying. The current data suggest that mate ameliorates metabolic syndrome by mechanisms involving increase of peripheral insulin sensitivity and cellular glucose uptake, and by modulating the level of circulating lipid metabolites and AD. These results indicate that mate can induce protective and ameliorative effects on insulin resistance, diabesity, and dyslipidemia in metabolic syndrome.