Expressions of CD147, matrix metalloproteinase-9 in carotid atherosclerotic plaque and the interference effect of atorvastatin on them

Objective To investigate the expression of CD147 and matrix metalloproteinase-9 （MMP-9） in rabbit models of carotid atherosclerotic plaque and the interference effect of atorvastatin on their expressions. Methods Twenty-four New Zealand white male rabbits were randomly divided into group A （normal diet group, n=8）, and group B （n=16）. Group A was given normal diet for 16 weeks. The 16 rabbits in group B underwent balloon-induced endothelial injury in the right carotid artery, and thereafter, were fed with a high-cholesterol diet （1% cholesterol） for 12 weeks; then, these rabbits were divided into group C （the model control group）, and group D （undergoing gastric perfusion of atorvastatin Russell＇s viper venom and histamine. The damaged carotid arteries in all the groups were collected to undergo pathological examination. The protein expressions of MMP-9 and CD147, and the level of macrophages were detected by immunohistochemical analysis, and the mRNA expressions of MMP-9 and CD147 were evaluated by reverse-transcription PCR. Results In group C, it was found that plaque disruption and thrombosis occurred in 4 out of the 6 rabbits after triggering, while in group D, only 1 rabbit demonstrated plaque disruption and thrombosis; however, rabbits in the normal diet group did not have plaque disruption and thrombosis. Group D showed significantly decreased level of macrophage （16.22±2.61）, decreased percentages of positive staining area of protein expression levels of MMP-9 （11.11±1.87） and CD147 （14.22±1.63） as compared with group C （33.62±3.82, 21.18±4.75 and 29.54±3.03, respectively） （P〈0.05）. Significant difference on the mRNA expression levels of CD147 and MMP-9 was noted between group C （0.939±0.105, 0.335±0.069, respectively） and group D （0.4256±0.112, 0.135 ±0.067, respectively） （P〈0.05）. The levels of the protein, mRNA expressions of CD 147 and MMP-9 were correlative positively by Pearson＇s correlation coefficient （r=0.669, 0.783, respectively, P=0.001, P=0.000）. Conclusion The up-expression of CD147 and MMP-9 may be involved in the pathogenesis of vulnerable carotid atherosclerotic plaque and atorvastatin can stabilize the plaque possibly through inhibiting the CD 147, and MMP-9 expressions. Key words: Atherosclerosis CD147 Matrix metalloproteinase-9 Atorvastatin