Study on the relationship of transforming growth factor-β1 and a disintegrin and metalloproteinase with thrombospondin motif-4 in carotid atherosclerotic plaques

Abstract

Objective To investigate the relationship between the expression level of transforming growth factor-β1 (TGF-β1) and a disintegrin and metalloproteinase with thrombospondin motif-4 (ADAMTS4) in human carotid atherosclerotic (AS) plaques. Methods Plaque tissues (n=46) were collected after carotid endarterectomy and divided into stable plaque group and unstable plaque group according to the histopathological features by hematoxylin and eosin (HE) staining. Immunohistochemistry (IHC) and real-time quantitative reverse transcriptase-polymerase chain reaction (RT-qPCR) were used to detect the expression of ADAMTS4 and TGF-β1 in plaques, respectively. Umbilical arteries were served as the control group (n=10) and statistics analysis were conducted as needed. Results IHC results showed that both of ADAMTS4 and TGF-β1 were expressed in all plaques; RT-qPCR results showed that the expression level of ADAMTS4 mRNA was significantly higher in unstable plaque group (4.43±2.02) compared to the stable plaque group (3.16±1.57) and the controls (1.02±0.22, F=17.545, P<0.05); TGF-β1 mRNA in stable plaque group (4.68±1.42) was also higher than that in the unstable plaques (3.57±1.76) and the controls (1.14±0.31), and the difference was statistically significant between groups (F=24.676, P<0.05). Pearson correlation analysis showed that there existed a positive correlation between indexes (r=0.439, P<0.05). Conclusion ADAMTS4 and TGF-β1 were increased together during the process of AS and plaque evolution, which may be related to dose or cell type dependence. Key words: Carotid atherosclerosis; Unstable plaques; Transforming growth factor-β1; A disintegrin and metalloproteinase with thrombospondin motif-4