[Effects of Guanxinkang on expressions of ATP-sensitive potassium channel subunits Kir6.1, Kir6.2, SUR2A and SUR2B in ischemic myocytes of rats]

Chinese Herbal Medicine on Cardiovascular Diseases and the Mechanisms of Action

Cardiovascular diseases are the principal cause of death worldwide. The potentially serious adverse effects of therapeutic drugs lead to growing awareness of the role of Chinese herbal medicine in the treatment of cardiovascular diseases. Chinese herbal medicine has been widely used in many countries especially in China from antiquity; however, the mechanisms by which herbal medicine acts in the prevention and treatment of cardiovascular diseases are far from clear. In this review, we briefly describe the characteristics of Chinese herbal medicine by comparing with western medicine. Then we summarize the formulae and herbs/natural products applied in the clinic and animal studies being sorted according to the specific cardiovascular diseases. Most importantly, we elaborate the existing investigations into mechanisms by which herbal compounds act at the cellular levels, including vascular smooth muscle cells, endothelial cells, cardiomyocytes and immune cells. Future research should focus on well-designed clinic trial, in-depth mechanic study, investigations on side effects of herbs and drug interactions. Studies on developing new agents with effectiveness and safety from traditional Chinese medicine is a promising way for prevention and treatment of patients with cardiovascular diseases.

Effect of electronic stimulation at Neiguan (PC 6) acupoint on gene expression of adenosine triphosphate-sensitive potassium channel and protein kinases in rats with myocardial ischemia

OBJECTIVE

To investigate the effects of electronic stimulation at acupoints Neiguan (PC 6) and Lieque (LU 7) on the gene expression of the adenosine triphosphate (ATP)-Sensitive potassium channel (KATP: Kir6.1, Kir6.2, SUR2A, and SUR2B) and protein kinases (PKA, PKG, and PKCβ2) in myocardial cells of rats with myocardial ischemia (MI) induced by isoproterenol (ISO).

METHODS

Rats were randomly divided into a control, model, Neiguan (PC 6), Lieque (LU 7), and non-acupoint groups. The MI model was established by injecting rats with ISO. Electro-acupuncture treatment was given to the acupuncture groups, once a day for 7 days. Gene expression was analyzed with real-time PCR.

RESULTS

The gene expression of KATP and protein kinases in the model group was higher than those in the control group (P < 0.05). After acupuncture treatment, the KATP and protein kinase expression levels were significantly lower in the Neiguan (PC 6) and Lieque (LU 7) groups compared with the mod- el group (P < 0.05). The Neiguan (PC 6) group lowered these levels significantly more than that of the Lieque (LU 7) group (P < 0.05). No significant differences were observed between the model and non-acupoint groups (P> 0.05).

CONCLUSION

Our findings suggest that electronic needling of Neiguan (PC 6) can both reduce the gene expression of KATP and protein kinases in rats with ISO-induced MI.

Guanxinkang Decoction Exerts Its Antiatherosclerotic Effect Partly through Inhibiting the Endoplasmic Reticulum Stress

Purpose. To investigate the antiatherosclerotic effect of Guanxinkang (GXK) decoction on the apoptosis, mitochondrial membrane potential (MMP), and endoplasmic reticulum stress (ERS) of human umbilical vein endothelial cells (HUVEC) pretreated with homocysteinemia (HCY). Materials and Methods. HUVEC were randomly divided into 5 groups: (1) blank control group (control), (2) model control group (model), (3) GXK low dose group, (4) GXK medium dose group, and (5) GXK high dose group. For the three GXK groups, HCY was given to reach the concentration of 3.0 mmol/L after HUVEC had been incubated with rabbit serum containing GXK for two hours. At 3, 6, 12, and 24 h after HCY had been incubated with the cells, the HUVEC were collected for test of the apoptosis rate, MMP, and GRP78 protein (reflecting ERS). Results. In the model control group, the apoptosis rate and GRP 78 protein expression of HUVEC significantly increased (P < 0.05), while MMP significantly decreased (P < 0.05) compared with the blank control group. After GXK treatment of medium and high doses, the apoptosis rate and the GRP 78 protein expression significantly (P < 0.05) decreased, while MMP significantly increased (P < 0.05) in a time-dependent manner compared with the model control group. Conclusion. GXK can antagonize the injury of HUVEC caused by HCY and the antagonism effect increases with the concentration and treatment duration of GXK, with the possible mechanism of GXK antagonism being through inhibiting ERS caused by HCY.

[Effects of Chinese herbal medicine Guanxinkang on lipid metabolism and serum C-reactive protein, amyloid A protein and fibrinogen in apolipoprotein E-knockout mice with atherosclerosis]

OBJECTIVE

To observe the effects of Guanxinkang (GXK) decoction, a compound traditional Chinese herbal medicine, on serum lipids and apolipoprotein A I (ApoA I), apolipoprotein B (ApoB), apolipoprotein E (ApoE), C-reactive protein (CRP), serum amyloid A protein (SAA) and fibrinogen (Fbg) concentrations of ApoE-knockout mice with atherosclerosis, and to explore the mechanism of GXK decoction in anti-atherosclerosis.

METHODS

Seventy 6-week-old ApoE-knockout mice receiving a high-cholesterol diet were used to induce atherosclerosis and were randomly divided into 5 groups: untreated group, simvastatin group and low- (drug concentration is 0.864 g/mL), medium- (1.728 g/mL), and high-dose (3.456 g/mL) GXK groups. Another fourteen 6-week-old C57BL/6J mice were used as the normal control. Two 12-week-old mice were randomly selected from the normal control and the ApoE-knockout mice respectively to observe vulnerable plaque in the mouse's aortic by hematoxylin-eosin staining. Blood was collected from venous plexus of eye socket after gavage of corresponding drugs once daily for 8 weeks continuously, and then the serum was separated. Triglyceride (TAG) and total cholesterol (TC) were measured by enzyme-coupled assay; low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) were measured by selective precipitation method. Serum levels of ApoA I and ApoB were determined by turbidimetry. Double-antibody sandwich enzyme-linked immunosorbent assay was used to detect ApoE, CRP, SAA and Fbg concentrations in serum.

RESULTS

Compared with the normal control group, the levels of serum TC, TAG, LDL-C, ApoB, CRP, SAA and Fbg in the untreated group were increased (P<0.05), and the serum concentrations of HDL-C, ApoA I and ApoE in the untreated group were decreased (P<0.05). After treatment, GXK decoction and simvastatin improved the dyslipidemia by increasing the concentrations of ApoA I and HDL-C and decreasing the concentrations of TC, TAG, LDL-C, ApoB, CRP, SAA and Fbg (P<0.05). The high-dose GXK decoction had the most marked effects on SAA and Fbg and the serum lipids compared with the low-dose and medium-dose GXK and simvastatin.

CONCLUSION

GXK decoction may not only provide an active effect on hyperlipidemia, but also down-regulate the levels of serum CRP, SAA and Fbg. GXK decoction exerts an anti-atherosclerosis effect in ApoE-knockout mice.