hydroxysafflor-yellow-a and Hypertension

Hydroxysafflor yellow A (HSYA), the main chemical component of the safflower yellow pigments, is used extensively in traditional Chinese medicine for the treatment of cerebrovascular and cardiovascular diseases.. The present study determined the effects of HSYA on left ventricular hypertrophy after pressure overload and investigated the underlying mechanisms.. Cardiac hypertrophy was induced by the ligation of abdominal aorta in male Wistar rats. The rats were then divided into five groups and treated with captopril (100 mg/kg) or HSYA at different doses (0, 10, 20 and 40 mg/kg). Six weeks after treatment, the weight of left ventricle, LVMI (left ventricular mass index) and pathological changes were measured. MMP-2 (metalloproteinase 2) and MMP-9 (metalloproteinase 9) levels were determined by ELISA. Protein expressions of Bcl-2 and Bax were evaluated by immunohistochemistry.. HSYA (20, 40 mg/kg) significantly attenuated the increase of LVMI (ventricular weight/body weight) by 13.04 and 30.43% respectively, when compared with the model group. This was associated with the amelioration of pathological lesion, such as cardiac muscle fibers were smaller and the nuclei of cardiomyocytes were lightly stained in animals treated with HSYA (20, 40 mg/kg). In addition, the administration of HSYA at doses of 20 and 40 mg/kg increased the Bcl-2/Bax ratio (1.17 ± 0.08 and 1.39 ± 0.07 versus 0.71 ± 0.06). In addition, the serum MMP-2 and MMP-9 levels were blocked by the treatment at doses of 20 and 40 mg/kg HSYA (MMP-2, 76.1 ± 9.2 and 65.6 ± 6.8 versus 82.9 ± 6.2, ng/ml; MMP-9, 66.6 ± 4.8 and 57.5 ± 5.0 versus 83.5 ± 6.0, ng/ml).. These findings indicated that HSYA has beneficial effects on hypertensive ventricular remodeling, which may involve mechanisms of inhibiting cell apoptosis and suppressing metalloproteinases expression.

Topics: Animals; Apoptosis; Captopril; Cardiomegaly; Carthamus tinctorius; Chalcone; Disease Models, Animal; Dose-Response Relationship, Drug; Enzyme-Linked Immunosorbent Assay; Hypertension; Male; Matrix Metalloproteinase 2; Matrix Metalloproteinase 9; Medicine, Chinese Traditional; Myocytes, Cardiac; Quinones; Rats; Rats, Wistar; Ventricular Remodeling

This work aims to investigate the effects of HSYA on cardiac function and blood pressure.. To evaluate changes in mean arterial pressure (MAP) and heart rate (HR), different groups of pentobarbitone-anesthetized normotensive and spontaneously hypertensive rats (SHR) were treated with intravenous HSYA (0.1-3 mg/kg). Isolated WKY rat hearts in Langendorff system were employed for examining the effect of HSYA on hemodynamic. After 30 min equilibration time the isolated hearts were perfused with HSYA (30 μmol/L) in a stepwise fashion. Potassium channel inhibitors were used to determine the role of potassium channel activation in HSYA effect.. Intravenous injection of the HSYA significantly reduced MAP and HR in both normotensive rats and SHR in a dose-dependent manner. HSYA reduced left ventricular systolic pressure (LVSP), left ventricular end-diastolic pressure (LVEDP), the maximum rate of increase of left ventricular pressure (+dp/dt(max)) and heart rate (HR) in a dose-dependent manner. HSYA had no remarkable effect on the maximum rate of decrease of left ventricular pressure (-dp/dt(max)); BK(Ca) and K(ATP) blocker can weakened the inhibitory effect of HSYA on heart function and HR, but K(V) and K(ACh) blocker did not significantly weaken the HSYA effects.. Our results show that HSYA could significantly reduce blood pressure and heart rate, which may be related to activation of BK(Ca) and K(ATP) channels.

Topics: Animals; Antihypertensive Agents; Blood Pressure; Calcium Channel Blockers; Calcium Channels; Carthamus tinctorius; Chalcone; Dose-Response Relationship, Drug; Flowers; Heart Rate; Hypertension; Plant Extracts; Potassium Channel Blockers; Potassium Channels; Quinones; Rats; Rats, Inbred SHR; Rats, Inbred WKY; Reference Values; Ventricular Function, Left