重组人脑利钠肽抑制氧化型低密度脂蛋白诱导的巨噬细胞凋亡及其相关机制

Inhibition of oxidised low-density-liporotein-induced apoptosis of macrophages by recombinant human brain natriuretic peptide and the underlying mechanism

目的:观察重组人脑利钠肽(rhBNP)对氧化型低密度脂蛋白(ox-LDL)诱导的THP-1源巨噬细胞凋亡的影响,并初步探讨其机制。方法:建立ox-LDL诱导巨噬细胞凋亡的模型。收集干预好的细胞,采用流式细胞仪检测各组细胞凋亡率及线粒体膜电位的变化;应用共聚焦显微镜测定细胞内活性氧(ROS)水平。结果:ox-LDL以浓度依赖方式诱导巨噬细胞凋亡,与control组相比,100μg/ml ox-LDL呈现出最大的凋亡率[(45.62±2.76)%∶(6.81±1.94)%,P<0.05]。rhBNP可以抑制ox-LDL诱导的巨噬细胞凋亡,在10^(-9) mol/L抑制作用最大(18.56±1.79)%,P<0.05。与control组相比,100μg/ml ox-LDL组ROS水平升高,而线粒体膜电位降低[(527.30±36.20)%∶(100.00±0.00)%,(3.01±0.52)%∶(9.67±0.51)%,P<0.05];10^(-9) mol/L rhBNP逆转这些变化[(237.30±30.62)%,(6.55±1.57)%,P<0.05]。结论:rhBNP抑制ox-LDL诱导的THP-1源巨噬细胞凋亡,其机制可能与调节氧化应激及抑制线粒体电位降低相关。

Objective：To investigate the effects of recombinant human brain natriuretic peptide（rhBNP）on oxidised low-density lipoprotein（ox-LDL）-induced macrophage apoptosis and explored the mechanism underlying the activity of rhBNP.Method：A model of ox-LDL-induced macrophage injury was established to evaluate the effect of rhBNP.Flow cytometry was employed to detect apoptosis and changes in mitochondrial membrane potential（MMP orΔΨm）,and confocal microscopy was used to determine the cellular reactive oxygen species（ROS）levels.Result：ox-LDL induced macrophage apoptosis in a concentration-dependent manner,peaking at 100μg/ml ox-LDL[（45.62±2.76）%∶（6.81±1.94）%,P〈0.05].Conversely,rhBNP suppressed macrophage apoptosis,inducing a maximal effect at 10^-9 mol/L（18.56±1.79）%,P〈0.05.Compared with the control group,in the100μg/ml ox-LDL group,the intracellular ROS levels were increased,ΔΨm was decreased[（527.30±36.20）%∶（100.00±0.00）%,（3.01±0.52）% ∶（9.67±0.51）%,respectively,P〈0.05];the effect was significantly counteracted by 10^-9 mol/L rhBNP [（237.30±30.62）%,（6.55±1.57）%,P〈0.05].Conclusion：rhBNP attenuates ox-LDL-induced macrophage apoptosis by suppressing oxidative stress and preserving the mitochondrial membrane potential.