组蛋白去乙酰化酶8对大鼠骨髓间充质干细胞成骨分化的影响

目的：探讨组蛋白去乙酰化酶8（histone deacetylase 8，HDAC8）对大鼠骨髓间充质干细胞（bone marrow mesenchymal stem cells，BMSCs）成骨分化的影响。方法：通过全骨髓贴壁法体外分离培养大鼠 BMSCs，转染 HDAC8过表达慢病毒载体，并于矿化诱导液中培养7 d后，实时荧光定量PCR、Western blot检测BMSCs成骨分化能力的变化；矿化诱导14 d后，茜素红钙结节染色检测BMSCs矿化能力的变化。组蛋白去乙酰化酶抑制剂---曲古抑菌素A（trichostatin A，TSA）刺激转染HDAC8过表达慢病毒载体的 BMSCs，于矿化诱导液中培养7 d后，实时荧光定量 PCR及 Western blot检测 TSA刺激前后过表达 HDAC8的BMSCs成骨分化能力的变化。结果：HDAC8过表达组经矿化诱导7 d 后，成骨分化相关基因 mRNA、蛋白表达水平均低于空白对照组；经14 d矿化诱导后，HDAC8过表达组茜素红钙结节的着色程度及范围低于空白对照组。TSA 刺激的 HDAC8过表达组矿化诱导7 d后，成骨分化相关基因 mRNA及蛋白的表达均高于未加刺激组（P＜0．05）。结论：HDAC8对大鼠 BMSCs成骨分化具有抑制作用。

Effect of histone deacetylase 8 on osteoblast differentiation of rat bone marrow mesenchymal stem cells

Objective：To evaluate the effect of histone deacetylase 8 （HDAC8）on osteoblast differentiation of rat bone marrow mes-enchymal stem cells （BMSCs）.Methods：Rat BMSCs were isolated and cultured by the method of whole bone marrow adherent and transfected with HDAC8 overexpression lentiviral vector.Real-time PCR,Western blot were applied to estimate the change of osteogen-ic capacity after 7 days of osteogenic induction and Alizarin red stain was used to estimate the mineralization capacity after 1 4 days of osteogenic induction.Trichostatin A （TSA）,one kind of histone deacetylase inhibitor,acted on BMSCs with HDAC8 overexpression and the change of osteogenic capacity of cells after 7 days of osteogenic induction was estimated by real-time PCR and Western blot. Results：For BMSCs with HDAC8 overexpression,the expression of osteogenesis-related genes at mRNA and protein levels were all low-er than those in control group after 7 days of ostogenic induction and the capacity to form calcified nodules was lower than that of the control group after 1 4 days of ostogenic induction.The osteogenesis-related genes expression of BMSCs with HDAC8 overexpression which was treated with TSA were all higher than those in untreated group after 7 days of ostogenic induction （P〈0.05）.Conclusions：HDAC8 could suppress osteogenic differentiation of rat BMSCs.