高磷对大鼠血管平滑肌细胞钙化及核心结合因子α1表达的影响

Effect of high phosphate on calcification and core binding factor α1 expression in cultured rat vascular smooth muscle cells

关键词:  血管平滑肌细胞  高磷  血管钙化  核心结合因子α1

Key words:  vascular smooth muscle cell (VSMC)  high phosphate  vascular calcification  core binding factorα1(Cbfα1)

摘要:

［目的］研究高磷对体外培养大鼠血管平滑肌细胞（VSMC）钙沉积以及核心结合因子α1 （Cbfα1）的影响。［方法］体外培养大鼠主动脉平滑肌细胞，根据培养基中磷浓度分为：正常磷浓度（磷浓度1.4 mmol/L）和高磷浓度（磷浓度2.4 mmol/L）组，培养第3 d、6 d、9 d后，BCA法检测细胞内钙含量，放射免疫方法检测培养液骨钙素含量，ELISA检测细胞Cbfα1与DNA结合活性。 ［结果］正常磷浓度组VSMCs钙含量在9 d内无明显变化。高磷浓度组第3、6、9天细胞钙含量比第0天明显增高（P<0.01）。高磷浓度组细胞钙含量在第3、6、9天均明显高于相同时间点正常磷浓度组（P<0.05）。培养3 d后，高磷浓度组培养上清液骨钙素水平明显高于正常磷浓度组，（14.62±2.93）pg/μg蛋白vs （2.83±0.64）pg/μg蛋白，P<0.01。Cbfα1活性在正常磷浓度组细胞9 d内无明显变化；但在高磷浓度组6、9天与第0天比明显增强（P<0.05）。高磷浓度组在第6、9天细胞Cbfα1活性与相同时间点正常磷浓度组比明显增强（P<0.05）。［结论］高磷可直接刺激大鼠VSMC的钙沉积和骨钙素产生，其作用可能与高磷上调VSMC的Cbfα1表达有关。

Abstract:

［Objective］To investigate the effect of high phosphate on calcification and the expression of core binding factor α1(Cbfα1) of rat vascular smooth muscle cells (VSMC). ［Methods］Rat aortic VSMC were cultured for 3、6 or 9 days. cells were divided into two groups: normal phosphate group (medium containing 1.4 mmol/L phosphate) and high phosphate group (medium containing 2.4 mmol/L phosphate). Calcium deposition in cells was measured by BCA. Osteocalcin levels were detected by radioimmun assay. The expression of Cbfα1 was detected by ELISA.［Results］No significant change was found for 9 days in normal phosphate group. The calcium depositions in 3 d, 6 d and 9 d were significantly more than that in 0 d in high phosphate group (P<0.01). The calcium deposition in 3 d, 6 d and 9 d in high phosphate group were significantly more than those in normal phosphate group at same times (P<0.05). After culture for 3 days, osteocalcin level of supernatant in high phosphate group was significantly more than that in normal phosphate group, (14.62±2.93)pg/μg protein vs (2.83±0.64)pg/μg protein, P<0.01. The Cbfα1 activities in 6 d and 9 d were significantly stronger than that in 0 d in high phosphate group (P<0.05). The Cbfα1 activities in 6 d and 9 d in high phosphate group were significantly stronger than those in normal phosphate group at same times (P<0.05). ［Conclusion］High phosphate may directly increase calcium deposition and osteocalcin level in rat VSMC, this change is possibly related to Cbfα1 up-regulation stimulated by high phosphate in VSMC.