Adiponectin and its receptor are considered as an important metabolic syndrome biomarker and therapeutic target. Green tea is widely consumed worldwide and its catechins is an attractive candidates in treating metabolic syndrome. This study aimed to investigate the effect of green tea extract administration on adiponectin and its receptor gene expression in metabolic syndrome rat models.
Thirty Sprague Dawley Metabolic Syndrome Rat Model weighed 300 – 400 grams were divided into EGCG 200 (n = 5), EGCG 300 (n = 5), and EGCG 400 (n = 5) groups. Moreover, as control groups fifteen rats were divided into normal control (NC) (n = 5), simvastatin and metformin treated (SM) (n = 5), and metabolic syndrome (MS) (n = 5) groups. Rats in the EGCG groups were treated once daily with green tea extract at a dose of 200, 300, and 400 mg/bw.t respectively. Moreover, Rats in the SM group were treated daily with 10 mg/bw.t of simvastatin and 200 mg/bw.t of metformin. The extract as well as the drug were administrated for 9 weeks through oral gavage. Fasting blood glucose, triglyceride, and HDL level was measured every two weeks by colorimetric method. Blood pressure was determined by tail cuff blood pressure recorder. Adiponectin level was analyzed by ELISA method. Adiponectin receptor gene expression was analyzed by RT-PCR methods.
After administration of green tea extract for 9 weeks, fasting blood glucose, triglyceride, and systolic blood pressure were significantly lower (p < 0.05), and HDL-Cholesterol was significantly higher in all EGCG groups compared to that of MS group. Moreover, adiponectin level was similar between EGCG 200 grup and MS group (p > 0.05). In contrast, the adiponectin level in EGCG 300 and EGCG 400 group was significantly higher (p < 0.05) compared to that of MS group. On the other hand, the adiponectin level was similar among all EGCG group compared to that of SM group. Furthermore, adiponectin receptor gene expression in EGCG 300 and EGCG 400 group were significantly higher compared to that of MS group (p < 0.05). In contrast, adiponectin receptor gene expression in EGCG 200 group was not significantly higher compared to that MS group.
Administration of green tea extract at a dose of 300 and 400 mg/bw.t for 9 weeks improved adiponectin level and adiponectin receptor gene expression in metabolic syndrome rat model
Brawijaya Cardiovascular Research Center, Department of Cardiology and Vascular Medicine, Faculty of Medicine Brawijaya University, Department of Nursing, Faculty of Medicine Brawijaya University