RESUMO
AIMS: Marrubiin and an organic extract of Leonotis leonurus were tested in vitro and in vivo for their antidiabetic and anti-inflammatory activities. MATERIALS AND METHODS: INS-1 cells were cultured under normo- and hyperglycemic conditions conditions. An in vivo animal model confirmed the biological activities of marrubiin and the organic extract observed in the studies in vitro. RESULTS: The stimulatory index of INS-1 cells cultured under hyperglycemic conditions was significantly increased in cells exposed to the organic extract and marrubiin, relative to the hyperglycaemic conditions. Insulin and glucose transporter-2 gene expressions were significantly increased by the organic extract and marrubiin. Similarly, the extract and marrubiin resulted in an increase in respiratory rate and mitochondrial membrane potential under hyperglycaemic conditions. Marrubiin increased insulin secretion, HDL-cholesterol, while it normalized total cholesterol, LDL-cholesterol, atherogenic index, IL-1ß and IL-6 levels in an obese rat model. CONCLUSION: The results provide evidence that marrubiin, a constituent of Leonotis leonurus, alleviates diabetic symptoms.
