Krüppel样因子4通过支持PPARγ信号通路维持细胞稳态以保护血管平滑肌细胞免受泡沫细胞样表型转化的损害
KLF4 Protects VSMCs from Damage of Foam Cell-like Phenotypic Transformation by Maintaining Cellular Homeostasis through Supporting PPARγ Signaling Pathway
张凯 1高尚 2刘丹3
作者信息
- 1. 石家庄学院化工学院,石家庄 050035;石家庄市靶点药物研究与药效学评价重点实验室,石家庄 050035
- 2. 石家庄学院化工学院,石家庄 050035
- 3. 河北医科大学生物化学与分子生物学系,石家庄 050017
- 折叠
摘要
动脉粥样硬化(AS)被普遍认为是一种血管壁细胞(包括内皮细胞和血管平滑肌细胞)、循环细胞以及固有免疫原性细胞(例如单核细胞/巨噬细胞)等多种细胞综合作用引起的炎症性疾病.其中血管平滑肌细胞(VSMCs)胆固醇超负荷形成的泡沫细胞可能在动脉粥样硬化的进展中发挥重要作用.Krüppel样因子4(KLF4)是一种关键的抗炎转录因子,尤其在心血管疾病方面,已被证实发挥了重要的血管功能保护作用.然而,目前尚不清楚KLF4是否在AS过程胆固醇对VSMCs的损伤中发挥保护作用.该研究旨在探讨KLF4在AS进展过程中VSMCs泡沫细胞样表型转化的作用及其分子机制.小鼠AS造模结果显示,KLF4缺失增加动脉粥样硬化斑块面积(P＜0.05),并增加动脉壁脂质蓄积(P＜0.05)及血清胆固醇含量(P＜0.05),加速AS进展.细胞内油红O染色及胆固醇含量测定研究证实,KLF4缺失促进VSMCs内胆固醇蓄积(P＜0.05).QRT-PCR和Western印迹结果证实,KLF4缺失促进VSMCs胆固醇摄取、合成、促炎因子分泌及巨噬细胞黏附和胆固醇损伤诱导的巨噬细胞标志物的表达(P＜0.05),抑制胆固醇流出和氧化相关基因及收缩表型标志物的表达(P＜0.05),加速VSMCs源性泡沫细胞形成.KLF4敲除VSMCs中利用腺病毒Ad-GFP-KLF4补救表达KLF4,显著逆转上述改变,并阻断由胆固醇蓄积诱导的TLR4-MyD88-p65通路的激活.随后,siRNA诱导的过氧化物酶体增殖物激活受体γ(PPARγ)的选择性基因消融消除了KLF4的这些作用.总之,我们的研究结果提示,KLF4通过激活PPARγ途径,抑制胆固醇摄取和合成,加速胆固醇流出,同时抑制促炎因子分泌、巨噬细胞黏附和胆固醇损伤诱导的巨噬细胞标志物表达,从而在VSMCs中实现对胆固醇刺激的保护作用.
Abstract
Atherosclerosis is popularly recognized as a multifaceted inflammatory disease that associated with varies cells in vascular wall[including endothelial cells and vascular smooth muscle cells(VSMCs)]and circulating as well as resident immunogenic cells(such as monocytes/macrophages).Foam cells formed by cholesterol-overload VSMCs may play an essential role in the progression of athero-sclerosis.Krüppel-like factor 4(KLF4),a key anti-inflammatory transcriptional factor,has been shown a beneficial effect on vascular function,especially in regard of cardiovascular disease.However,it is un-clear that whether KLF4 may play a protective role in the damage of cholesterol to VSMCs.The aim of this study was to investigate the role of KLF4 in the process of foam cell-like phenotypic transformation of VSMCs during atherosclerosis progression and its underlying molecular mechanism.The results of athero-sclerosis modeling in mice showed that KLF4 disruption accelerated atherosclerosis progression.Intracel-lular oil red O staining and cholesterol content assay confirmed that loss of KLF4 promoted cholesterol ac-cumulation in VSMCs.The results of qRT-PCR and Western blot confirmed that KLF4 deletion promoted cholesterol uptake,synthesis,pro-inflammatory factor secretion,macrophage adhesion and expression of macrophage markers which induced by cholesterol damage,and meanwhile inhibited cholesterol efflux and oxidation-related genes as well as contractive phenotypic markers expression,which finally resulted in VSMCs-derived foam cell formation.Furthermore,rescue expression of KLF4 notably reversed above changes.Additionally,KLF4 blocked the activation of TLR4-MyD88-p65 pathway induced by cholesterol accumulation and upregulated the expression of proteins important for cholesterol efflux.SiRNA-induced selective gene ablation of peroxisome proliferator-activated receptor γ(PPARγ)abolished these effects of KLF4.In conclusion,our results suggest that KLF4 exerts a protective effect on cholesterol stimulation in VSMCs by activating PPARγ pathway,inhibiting cholesterol uptake and synthesis,accelerating choles-terol efflux,and meanwhile preventing pro-inflammatory cytokines secretion,macrophage adhesion,and macrophage markers expression.
关键词
Krüppel样因子4/过氧化物酶体增殖物激活受体γ/动脉粥样硬化/血管平滑肌细胞/泡沫细胞样表型转化Key words
Krüppel-like factor 4(KLF4)/peroxisome proliferator-activated receptor γ(PPARγ)/atherosclerosis/vascular smooth muscle cells(VSMCs)/foam cell-like phenotypic transformation引用本文复制引用
基金项目
石家庄学院博士科研启动基金(20BS006)
河北省高层次人才项目(B2022005008)
国家自然科学基金(41471198)
出版年
2024
NETL
NSTL
维普
万方数据