骨钙素在血管钙化中的作用机制OA

Objective To investigate the role and underlying mechanisms of osteocalcin in vascular calcification.Methods Forty healthy female Sprague-Dawley rats were randomly assigned to five groups(n=8 per group):normal group,sham-operated plus calcification group,ovariectomy plus calcification group,osteocalcin-silencing group(ovar-iectomy+calcification+osteocalcin silencing),and negative control silencing group(ovariectomy+calcification+negative control).Except for the normal group,vascular calcification was induced in all groups by vitamin D3 administra-tion.Osteocalcin gene silencing was performed in the osteocalcin-silencing group.Serum lipid profiles were measured.Vascular calcification was evaluated by Von Kossa staining.The mRNA and protein expression levels of osteocalcin(bone Gla protein,BGP)and runt-related transcription factor 2(Runx2)were determined using reverse transcription quantita-tive polymerase chain reaction(RT-qPCR)and Western blot analysis,respectively.Results Compared with the nor-mal group,low-density lipoprotein cholesterol(LDL-C)levels were significantly increased in all calcification groups,including the sham-operated plus calcification,ovariectomy plus calcification,osteocalcin-silencing,and negative con-trol groups(P＜0.05).Von Kossa staining demonstrated marked medial vascular calcification in all calcification groups compared with the normal group.Osteocalcin silencing significantly attenuated vascular calcification compared with the negative control group(P＜0.05).The mRNA and protein expression levels of BGP and Runx2 were significantly in-creased in all calcification groups compared with the normal group(P＜0.05).Following osteocalcin silencing,both BGP and Runx2 mRNA and protein expression levels were significantly reduced compared with the negative control group(P＜0.05).Conclusion Osteocalcin participates in the development and progression of vascular calcification and may pro-mote vascular calcification by upregulating Runx2 expression.