细胞凋亡在维生素 K2抑制高磷诱导的大鼠血管平滑肌细胞钙化中的作用

摘要

Objective To explore the effects of vitamin K2 on high - phosphorus - induced calcification of rat vascular smooth muscle cells(VSMCs),and the role played by cell apoptosis. Methods A total of 6 healthy female SD rats aged 8 - 10 weeks were selected,VSMCs from rat thoracic aorta were cultured in vitro,and identified by immunocytochemistry. VSMCs were randomly divided into 5 groups by random number table method:control group,high phosphorus group,vitamin K2 group 1(10μmol/ L),vitamin K2 group 2(25 μmol/ L),vitamin K2 group 3(50 μmol/ L). The cell calcium content,the expression of Axl and Bcl - 2 mRNA,and the cell apoptosis rate were measured. Results There was significant difference in calcium content of VSMCs among 5 groups of rats(P ﹤ 0. 05). The VSMCs calcium level in high phosphorus group,vitamin K2 group 1,vitamin K2 group 2,vitamin K2 group 3 was significantly higher than that in control group,respectively( P ﹤ 0. 05). The VSMCs calcium level in vitamin K2 group 1,vitamin K2 group 2,vitamin K2 group 3 was significantly lower than that in high phosphorus group,respectively(P ﹤ 0. 05). The VSMCs calcium level in vitamin K2 group 2,vitamin K2 group 3 was significantly lower than that in vitamin K2 group 1,respectively(P ﹤ 0. 05). The VSMCs calcium level in vitamin K2 group 3 was significantly lower than that in vitamin K2 group 2( P ﹤ 0. 05). There was significant difference in the expression level of Axl mRNA in VSMCs among 5 groups of rats(P ﹤ 0. 05). The expression level of VSMCs Axl mRNA in high phosphorus group and in vitamin K2 group 1 was significantly lower than that in control group,respectively( P ﹤ 0. 05). The expression level of VSMCs Axl mRNA in vitamin K2 group 3 was significantly higher than that in control group(P ﹤ 0. 05). The expression level of VSMCs Axl mRNA in vitamin K2 group 2 and in vitamin K2 group 3 was significantly higher than that in high phosphorus group,respectively (P ﹤ 0. 05). There was no significant difference in the expression level of Bcl - 2 mRNA in VSMCs among 5 groups of rats(P ﹥0. 05). There was significant difference in VSMCs apoptosis rate among 5 groups of rats(P ﹤ 0. 05). The VSMCs apoptosis rate in high phosphorus group and in vitamin K2 group 1 was significantly higher than that in control group,the VSMCs apoptosis rate in vitamin K2 group 1,in vitamin K2 group 2 and in vitamin K2 group 3 was significantly lower than that in high phosphorus group,respectively(P ﹤ 0. 05). Conclusion Vitamin K2 can inhibit high - phosphorus - induced calcification of rat VSMCs, may alleviate VSMCs apoptosis by increasing Gas6 / Axl expression,the mechanism is probably that vitamin K2 may alleviate VSMCs apoptosis by increasing Gas6 / Axl expression.%目的：探讨维生素 K2对高磷诱导的大鼠血管平滑肌细胞（VSMCs）钙化的影响及细胞凋亡在其中所起的作用。方法选取8~10周龄健康雄性 SD 大鼠6只，分别体外分离培养大鼠胸主动脉 VSMCs，采用免疫细胞化学方法鉴定。将 VSMCs 采用随机数字表法分为正常对照组、高磷组、维生素 K2组1（10μmol/ L）、维生素 K2组2（25μmol/ L）及维生素 K2组3（50μmol/ L）。检测 VSMCs 钙含量、Axl mRNA 和 Bcl -2 mRNA 表达、细胞凋亡率。结果5组大鼠 VSMCs 钙含量比较，差异有统计学意义（P ﹤0.05）。高磷组、维生素 K2组1、维生素 K2组2、维生素 K2组3均高于正常对照组（P ﹤0.05）；维生素 K2组1、维生素 K2组2、维生素 K2组3均低于高磷组（P ﹤0.05）；维生素K2组2、维生素 K2组3均低于维生素 K2组1（P ﹤0.05）；维生素 K2组3低于维生素 K2组2（P ﹤0.05）。5组大鼠VSMCs 中 Axl mRNA 表达水平比较，差异有统计学意义（P ﹤0.05）。高磷组、维生素 K2组1 Axl mRNA 表达水平低于正常对照组，维生素 K2组3 Axl mRNA 表达水平高于正常对照组，维生素 K2组2、维生素 K2组3 Axl mRNA 表达水平高于高磷组（P ﹤0.05）。5组大鼠 VSMCs 中 Bcl -2 mRNA 表达水平比较，差异无统计学意义（P ﹥0.05）。5组大鼠细胞凋亡率比较，差异有统计学意义（P ﹤0.05）。高磷组、维生素 K2组1细胞凋亡率高于正常对照组，维生素 K2组1、维生素 K2组2、维生素 K2组3细胞凋亡率低于高磷组（P ﹤0.05）。结论维生素 K2能够抑制高磷诱导的大鼠 VSMCs钙化，其机制可能是通过上调生长停滞特异基因6（Gas6）/ Axl 的表达而抑制了 VSMCs 的凋亡。