2024, Vol. 28 ›› Issue (2): 186-192

CXCL5 participates in carotid plaque formation by inducing vascular calcification

Qi Ming, Wang Lei, Zhang Zhen   

Abstract: BACKGROUND: CXC motif chemokine 5 (CXCL5) is a neutrophil activating peptide derived from epithelial cells, which may be involved in arterial diseases. However, there is yet no report on the effect of CXCL5 in vascular calcification.
OBJECTIVE: To explore the role of CXCL5 in the vascular calcification of carotid atherosclerosis (CAS).
METHODS: (1) Cytological experiment: Mouse vascular smooth muscle cells (VSMCs) were divided into five groups: osteogenic medium group, Vector group (vector, blank plasmid transfected into VSMCs), CXCL5 group (CXCL5 plasmid transfected into VSMCs), si-NC group (CXCL5 negative control siRNA transfected into VSMCs), si-CXCL5 group (CXCL5 siRNA transfected into VSMCs), Vector+LY2157299 group and CXCL5+LY2157299 group (LY2157299 transferred into the cells 24 hours after cell transfection). Alizarin red staining, alkaline phosphatase staining, and calcium content determination were performed to evaluate the osteogenic differentiation level of VSMCs. (2) Animal experiment: Forty-eight ApoE-/- mice were randomly divided into four groups (n=12 per group): Con+si-NC group, Con+si-CXCL5 group, CAS+si-NC group and CAS+si-CXCL5 group. Animal models were not prepared in the first two groups, in which si-NC or si-CXCL5 lentivirus was injected into the tail vein; carotid atherosclerosis models were made in the latter two groups, in which si-NC or si-CXCL5 lentivirus was injected into the tail vein. Von Kossa staining and immunohistochemical staining were used to evaluate carotid vascular calcification and the expression of CXCL5 and transforming growth factor-β receptor 1 (TGFBR1) in mice.
RESULTS AND CONCLUSION: In the CXCL5 group, the protein level of runt-related transcription factor 2 (RUNX2) was up-regulated and the level of α-smooth muscle actin was down-regulated, in contrary to the findings in the si-CXCL5 group. In addition, CXCL5 overexpression upregulated the level of TGFBR1, while CXCL5 knockdown inhibited the level of TGFBR1. Compared with the Vector group, the intensity of alizarin red staining, alkaline phosphatase activity and calcium content in the CXCL5 group increased significantly (P < 0.05). Compared with the si-NC group, the intensity of alizarin red staining, alkaline phosphatase activity and calcium content in the si-CXCL5 group decreased significantly (P < 0.05). When LY2157299 inhibited TGFBR1 expression, the osteogenic differentiation of VSMCs induced by CXCL5 was reduced. Compared with the Con+si-NC group, the expression of CXCL5 protein in the carotid artery and calcification area in the CAS+si-NC group increased significantly (P < 0.05). Compared with the CAS+si-NC group, the expression of CXCL5 protein in the carotid artery and vascular calcification area in the CAS+si-CXCL5 group decreased significantly (P < 0.05). In addition, compared with the Con+si-NC group, the expression of RUNX2 protein in the carotid artery in the CAS+si-NC group increased significantly (P < 0.05), while the expression of α-smooth muscle actin protein decreased significantly (P < 0.05). Compared with the CAS+si-NC group, the expression of RUNX2 protein in the carotid artery in CAS+si-CXCL5 group decreased significantly (P < 0.05), while the expression of α-smooth muscle actin protein increased significantly (P < 0.05). In conclusion, CXCL5 can induce osteogenic transformation of VSMCs by activating the TGFBR1 pathway, and inhibition of CXCL5 expression is effective in improving carotid arterial calcification in CAS mice.

Key words: CXC motif chemokine 5, carotid atherosclerosis, vascular calcification, vascular smooth muscle cell, transforming growth factor-β receptor 1