Study on the Cardiac and Cardiovascular Protection by Danshen and Gegen Decoction and Its Underlying Mechanisms

Coronary heart diseases (CHD) are one of the most prevalent causes of premature death all over the world. In contrast to western medicine, traditional Chinese medicine (TCM) has shown the benefit of multi-targeting and synergism to treat CHD. Two kinds of Chinese herbs, Danshen (Radix Salviae Miltiorrhiza) (D) and Gegen (Radix Puerariae Lobatae ) (G) always present on the TCM formula for treating heart disease. We found a useful formula of Danshen and Gegen decoction with weight ratio of 7:3 (DG) exerting properties of improving the heart function in patient with atheroslcerosis and providing vasodiation and antioxidant protection on the rat cardiovascular system. The present study was designed to evaluate the effects of DG on the vascular activity by its properties on antioxidant and anti-ion stunning to inhibiting the ischemia and reperfusion injury, vasodilation effect on pig coronary artery and angiogenesis effect on zebrafish model.;In the cell hypoxia and reoxygenation model, DG significantly inhibited the cell death after H/R treatment with bcl2 expression increase and caspase3 expression decrease. DG also reversed the H/R-induced mitochondrial depolarization and inhibited cytochrome c diffusing out of mitochondria, which confirmed DG anti-apoptosis activity. DG also was found to significantly decrease the intracellular calcium accumulation and reactive oxygen species release within H9c2.;In the second part of present study, results revealed that DG elicited a concentration-dependent relaxation of U46619-preconstricted porcine coronary artery. DG-induced relaxation responses were not altered by the presence of endothelium-related dilator inhibitors, most potassium channel blockers, GMP and AMP pathway inhibitors and endothelium removal. Ba2+ (an inward rectifier K+ channel blocker) slightly attenuated DG-induced relaxation. The protein expression of phosphorylated myosin light chain (MLC) was inhibited by DG in a concentration-dependent manner whereas the activity of RhoA was not modified. Ca2+-induced contraction of coronary artery was inhibited by DG in a concentration-dependent fashion. DG acted as an antagonist of calcium channel inducing the porcine artery dilation.;The third part of the present study is about the pro-angiogenic effect of DG. We found that DG dose-dependently induced zebrafish sub-intestinal vessel sprouting and increased the mRNA expression of vascular endothelial growth factor (VEGF) and its receptors. To explore the underlying mechanism, we also examined the proangiogenic effect of DG on the angiogenesis of endothelial cells. The results showed that DG induced the HMEC-1 proliferation, migration and forming tube.;In the first part of the study, we explored protective effect of DG on rat hearts and cardiomyocytes after ischemia-reperfusion and hypoxia-reoxygenation injury. Comparing to control group, the release of creatine kinase (CK) and lactate dehydrogenase (LDH) significantly decreased in the DG treated groups in a dose-dependent manner. The recovery percentage of coronary flow and contractile force in the DG was higher than that in the control group. These results suggested that DG dose-dependently improved the heart function after ischemia and reperfusion injury in a dose-dependent manner. We also examined chronic effect of DG (14 days pretreatment) on rat heart with ischemia and reperfusion injury. DG induced rat heart with high potential to deal with I/R injury, less damaged enzymes release and high recovery percentage of heart function recovery.;In conclusion, we found that DG could provide cardiac and cardiovascular protection by its multiple targets. It prevented heart injuries after ischemia or hypoxia and reperfusion through scavenging ROS and inhibiting calcium accumulation. Moreover, it mainly acts as an antagonist of L-type calcium channel to relax the contracted LAD vessel. It also exerted property of inducing angiogenesis in vivo and in vitro. Therefore, DG would be useful for treating coronary artery disease depending on its multiple targets.