Uremic serum induces osteogenic transition and calcification of human umbilical artery smooth muscle cells / 中华肾脏病杂志

ABSTRACT

Objective To study the effect of uremic serum on the calcification and osteogenic transition of cultured human umhilical artery smooth muscle cells(HUASMC).Methods Sera from 40 healthy controls(control group),40 nondialysis uremic patients(nondialysis group)and 45 uremic patients on dialysis(dialysis group)were detected fi)r biochemical indexes concerned and used to treat the cultured HUASMC.Alizarin red S stain was applied to examined calcium deposition in the cell layer.Calcium concentration was determined calorimetrically by the Ocresolphtha]ein complexone method,and corrected by total cell proteins.The mRNA expression of bone specific alkaline phosphatase(BAP),osteopontin(OPN)and bone morphogenelic protein 2(BMP2)was estimated by realtime PCR.OPN and BMP2 protein expression was assessed by Western blotting and fluorometry method was used to check the BAP concentration. Results Serum biochemical detection revealed thai both uremic groups had higher levels of phosphate,triglyseride,iPTH,C-reactive protein(CRP)and IL-6,and lower level of fetuin-A than healthy control(P＜0.05).Furthermore,dialysis serum had higher levels of triglyseride,CRP and IL-6 than nondialysis serum(P＜0.05).Compared with control group,both uremic scra induced more cell layer calcium deposition and higher mRNA and protein expression levels of BMP2,BAP and OPN(P＜0.05).Higher mRNA and protein expression levels of above factors were found in dialysis group as compared to nondialysis group(P＜0.05). Conclusions Uremic serum can induce HUASMC calcification and osteogenic transition in vitro,which may be one of the mechanisms involved in vascular calcification of ESRD patients.Microinflammatory state may promote the osteogenic transition and vascular calcification in dialysis patients.