OBJECTIVETo investigate the effect of the active components from Red Paeonia and Rhizoma chuanxiong (in Xiongshao Capsule, XSC) on matrix metalloproteinases (MMPs) in rabbit model of atherosclerosis.

METHODSFifty New Zealand rabbits were randomly divided into the normal control group (A), the model control group (B), the Simvastatin treated group (C), the low-dose XSC treated group (D) and the high-dose XSC treated group (E), 10 in each group. Rabbits in the normal control group were fed with normal diet, while those in the other four groups were fed with high fat diet and duplicated after two weeks feeding into model of abdominal aortic atherosclerosis by balloon angioplasty. In the 6 successive weeks feeding of high fat diet, Simvastatin 2.5 mg/kg, XSC 0.24 g/kg and 0.48 g/kg per day was given respectively to the rabbits in the three treated groups. Blood sample was collected for determining the level of blood lipids; serum MMP-3 and MMP-9, and tissue inhibitor of metalloproteinase-1 (TIMP-1) with enzyme-linked immunoassay; and the protein expression of MMP-3 and cluster of differentiation antigen 40 ligand (CD40L) in plaque were detected with immunohistochemical method.

RESULTSCompared with Group B, the serum levels of MMP-3 and MMP-9; the expression of MMP-3 and CD40L in plaque; and the blood content of total cholesterol in the three treated groups were significantly lower (P < 0.05 or P < 0.01). Besides, the content of triglyceride and low-density lipoprotein cholesterol were significantly reduced in Group C, while the TIMP-1 showed no statistical difference among different groups (P > 0.05).

CONCLUSIONThe active components of Red Paeonia and Rhizoma chuanxiong play a definite role in stabilizing the atherosclerotic plaque in rabbits, one of their possible mechanisms may be by way of inhibiting the expressions of MMP-3, MMP-9 in vascular walls and blood serum.

Animals ; Atherosclerosis ; drug therapy ; enzymology ; Drugs, Chinese Herbal ; pharmacology ; Male ; Matrix Metalloproteinase 3 ; blood ; Matrix Metalloproteinase 9 ; blood ; Paeonia ; chemistry ; Phytotherapy ; Rabbits ; Random Allocation ; Tissue Inhibitor of Metalloproteinase-1 ; blood

PURPOSE: Increased lipoprotein-associated phospholipase A2 (Lp-PLA2) activity and Rho kinase activity may be associated with atherosclerosis. The principal aim of this study was to examine whether darapladib (a selective Lp-PLA2 inhibitor) could reduce the elevated Lp-PLA2 and Rho kinase activity in atherosclerosis. MATERIALS AND METHODS: Studies were performed in male Sprague-Dawley rats. The atherosclerosis rats were prepared by feeding them with a high-cholesterol diet for 10 weeks. Low-dose darapladib (25 mg.kg-1.d-1) and high-dose darapladib (50 mg.kg-1.d-1) interventions were then administered over the course of 2 weeks. RESULTS: The serum levels of triglycerides, total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), high-sensitivity C-reactive protein (hs-CRP), and Lp-PLA2, significantly increased in atherosclerosis model groups, as did Rho kinase activity and cardiomyocyte apoptosis (p<0.05 vs. sham group), whereas nitric oxide (NO) production was reduced. Levels of TC, LDL-C, CRP, Lp-PLA2, and Rho kinase activity were respectively reduced in darapladib groups, whereas NO production was enhanced. When compared to the low-dose darapladib group, the reduction of the levels of TC, LDL-C, CRP, and Lp-PLA2 was more prominent in the high-dose darapladib group (p<0.05), and the increase of NO production was more prominent (p<0.05). Cardiomyocyte apoptosis of the high-dose darapladib group was also significantly reduced compared to the low-dose darapladib group (p<0.05). However, there was no significant difference in Rho kinase activity between the low-dose darapladib group and the high-dose darapladib group (p>0.05). CONCLUSION: Darapladib, a Lp-PLA2 inhibitor, leads to cardiovascular protection that might be mediated by its inhibition of both Rho kinase and Lp-PLA2 in atherosclerosis.
1-Alkyl-2-acetylglycerophosphocholine Esterase/*antagonists & inhibitors/blood/drug effects ; Animals ; Atherosclerosis/blood/*drug therapy/*enzymology ; *Benzaldehydes ; C-Reactive Protein/metabolism ; Cholesterol/blood ; Cholesterol, HDL/blood ; Cholesterol, LDL/blood ; Dose-Response Relationship, Drug ; Male ; *Oximes ; Phospholipase A2 Inhibitors/*administration & dosage/adverse effects ; Rats ; Rats, Sprague-Dawley ; Triglycerides/blood ; rho-Associated Kinases/*metabolism