Antihypertensive effect of total flavones extracted from seed residues of Hippophae rhamnoides L. in sucrose-fed rats

The study was designed to investigate the antihypertensive effect of total flavones extracted from seed residues of Hippophae rhamnoides L. (TFH-SR) and its underlying mechanism in chronic sucrose-fed rats by evaluating its ability to regulate insulin and angiotensin II levels. Feeding of high-sucrose diet (HS: 77% of kcal from carbohydrate, 16% from protein and 6% from lipid, respectively) for 6 weeks resulted in significant rise in systolic blood pressure (SBP) by 25.60%, plasma insulin by 114.24%, triglycerides by 85.14% and activated angiotensin II contents in heart and kidney. However, TFH-SR treatment significantly suppressed the elevated hypertension, hyperinsulinemia and dyshpidemia. Furthermore, TFH-SR (especially at the dose of 150 mg/kg/day) increased the circulatory blood angiotensin II level as effective as angiotensin II receptor blocker. These results indicated that TFH-SR exerted its antihypertensive effects at least in part by improving insulin sensitivity and blocking angiotensin II signal pathway. Findings of the present study suggested that TFH-SR might prove to be of potential use in the management of hyperinsulinemia in non-diabetic state with cardiovascular diseases. (C) 2008 Elsevier Ireland Ltd. All rights reserved.