IOX1对TGF-β诱导的LX2细胞增殖、凋亡及细胞外基质相关蛋白表达的影响

Effects of IOX1 on proliferation,apoptosis and extracellular matrix-related protein expression in LX2 cells induced by TGF-β

目的:探讨组蛋白去甲基化酶抑制剂IOX1(5-羧基-8-羟基喹啉)提高组蛋白H3第9位赖氨酸二甲基化(H3K9me2)水平对转化生长因子β(TGF-β)诱导的人肝星状细胞株LX2增殖、凋亡及细胞外基质合成和代谢的影响。方法:采用实时无标记细胞分析技术动态观察不同浓度IOX1对TGF-β诱导的LX2细胞增殖的影响。采用流式细胞术观察IOX1对TGF-β诱导的LX2细胞凋亡的影响。Western blot检测细胞中H3K9me2水平,以及α-平滑肌肌动蛋白(α-SMA)、Ⅰ型胶原(Col I)、基质金属蛋白酶1(MMP-1)和金属蛋白酶组织抑制物1(TIMP-1)蛋白的表达。结果:与对照组相比,不同浓度的IOX1均能抑制LX2细胞增殖。流式细胞术结果表明,IOX1能够促进LX2细胞凋亡(P<0.05)。Western blot结果发现,IOX1能提高LX2中H3K9me2水平,且呈剂量依赖性(P<0.05);与对照组相比,300μmol/L IOX1能够明显抑制TGF-β诱导的LX2细胞中α-SMA、TIMP-1和Col I蛋白的表达(P<0.05),MMP-1蛋白的表达在不同浓度IOX1组中表现为上升趋势(P<0.05)。结论:IOX1可抑制TGF-β诱导的LX2细胞增殖并促进细胞凋亡,还可通过提高H3K9me2水平调节细胞外基质的合成和代谢,从而发挥抗肝纤维化作用。

AIM:To investigate the effects of histone demethylase inhibitor IOX1(5-carboxy-8-hydroxyquinoline)on the proliferation,apoptosis and extracellular matrix(ECM)-related protein expression in transforming growth factor-β(TGF-β)-induced human hepatic stellate LX2 cells.METHODS:The proliferation and apoptosis of the LX2 cells were determined by real-time cell analysis and flow cytometry,respectively.The level of histone H3 lysine 9 dimethylation(H3 K9 me2)and the protein expression of ECM-related molecules[α-smooth muscle actin(α-SMA),collagen type I(Col I),matrix metalloproteinase-1(MMP-1)and tissue inhibitor of metalloproteinase-1(TIMP-1)]in the LX2 cells were detected by Western blot.RESULTS:Treatment with IOX1 at 50~300μmol/L significantly inhibited LX2 cell proliferation,and 300μmol/L IOX1 significantly promoted the apoptosis of the LX2 cells.In addition,different concentrations of IOX1 increased the levels of H3 K9 me2 and MMP-1,and down-regulated the expression ofα-SMA,Col I and TIMP-1 in TGF-β-induced LX2 cells(P<0.05).CONCLUSION:Treatment with IOX1 inhibits the proliferation of LX2 cells induced by TGF-β,promotes the cell apoptosis,and regulates the synthesis and metabolism of ECM by elevating H3K9 me2 level,thus attenuating hepatic fibrosis.