Study on the Synergistic Effect between Gynostemma pentaphyllum and Scutellaria baicalensis in Control of Diabetic Cardiopathy

Abstract:

Objective:To study the synergistic effect between Gynostemma pentaphyllum (GP) and Scutellaria baicalensis Georgi (SBG) in control of diabetic cardiopathy(DC), providing the scientific basis for the clinical application. Method: The in vitro effects of GP (0.5, 5, 50 mg·L^-1), SBG (0.5, 5, 50 mg·L^-1) and the mixture of GP extract and SBG extract (GPSBG, 0.5, 5, 50 mg·L^-1) on vascular endothelial cells, myocardial cells and mesangial cells were investigated. Rat model of DC was induced by high fat feeding and injection of streptozotocin(STZ)of 25 mg·kg^-1. The DC rats were randomly divided into GP 300 mg·kg^-1,SBG 300 mg·kg^-1,GPSBG 600 mg·kg^-1 and DC model group. The investigation groups were respectively ig given corresponding extracts once daily for 8 weeks, while the controls and the models were given the same volume of sodium carboxy methyl cellulose (0.5%). The cardiac hemodynamic indexes and serum lipids were measured at 24 hours after the last administration. Result: SBG 5 mg·L^-1and GPSBG 5 mg·L^-1could compete the suppression of ECV-304 growth in 30 mmol·L^-1 glucose, increasing NO generation, reduce GSH levels, compete the inhibition of mesangial cell proliferation in 30 mmol·L^-1 glucose medium. SBG 5 mg·L^-1, GP 5 mg·L^-1 and GPSBG 5 mg·L^-1could compete the suppression of ECV-304 growth, increase NO generation, reduce GSH levels by H₂O₂ on myocardial cell. GP 300 mg·kg^-1and SBG 300 mg·kg^-1 could decrease the cardiac index in typeⅡdiabetic rats, GPSBG 600 mg·kg^-1 could significantly reduce the serum levels of TG and TC, index of heart in typeⅡdiabetic rats. GP 300 mg·kg^-1 could significantly increase left ventricular systolic blood pressure and heart rate, left ventricular end-diastolic pressure, the rate index of left ventricular contraction and relaxation time, and lower left ventricular end-diastolic pressure. SBG 300 mg·kg^-1could significantly reduce left ventricular end-diastolic pressure, GPSBG 600 mg·kg^-1 could significantly increase heart rate, left ventricular systolic blood pressure, left ventricular contraction and relaxation time rate, reduce left ventricular end-diastolic pressure in typeⅡdiabetic rats. Conclusion: GP and SBG show synergistic effect on improving cardiac function in typeⅡdiabetic rats. This may be related to the effects of GP and SBG on reducing serum TG, TC in typeⅡ diabetic rats, and their effects on endothelial cells, myocardial cells, mesangium cells and aldose reductase.