JMJD3在动脉粥样硬化过程中作用及硫化氢调控研究

Macrophage polarization plays a pivotal role in the development - of atherosclerosis. Our previous results have demonstrated that histone H3 Lys 27 (H3K27) demethylase Jumonji domain containing-3 (JMJD3) promotes an inflammatory phenotype of macrophages in lipopolysaccharide-stimulated macrophages. Hydrogen sulfide (H2S) is endogenously generated by cystathionine γ-lyase (CSE) and has been demonstrated to influence a wide range of physiological and pathological processes in cardiovascular system. In addition, CSE/H2S markedly inhibited JMJD-mediated change of macrophage phenotype through a negative feedback mechanism. Therefore, JMJD3 may play a key regulatory role in the process of inflammatory response of atherosclerosis. Herein, it is the first time to explore CSE/H2S initiated feedback inhibition on the transcription of JMJD3 which plays a pivotal role in inflammatory responses and development of atherosclerosis as follows: 1) atherosclerosis was induced by high fat diet (HFD) in ApoE-/- mice and the plaque size，fibrous cap stability, M1/M2 macrophage ratio, inflammatory mediators, CSE activity and expression, H2S levels in atherosclerotic vascular were measured. A positive correlation of JMJD3 expression with atherosclerosis and a key role of JMJD3 in HFD-induced atherosclerosis were identified by combining lentiviral-mediated JMJD3 overexpression/knockdown and strategies of drug interference; 2) To elucidate feedback regulation by CSE/H2S on JMJD3, atherosclerosis was induced by HFD in ApoE/CSE double knockout and ApoE-/- mice. The plaque size，fibrous cap stability，M1/M2 macrophage ratio, inflammatory mediators, JMJD3 expression, H3K27 methylation levels in artery were compared. Alternatively, lentiviral CSE overexpression and drug interference will be used; 3) In above-mentioned cell and animal models by various molecular biology techniques, we further verify that the molecule mechanism is that CSE/H2S acts by sulfhydrating the p65 subunit of NF-κB at cysteine-38, which inhibits its binding to the JMJD3 promoter and reduces JMJD3 transcription. These findings will shed lights on the mechanistic insights during development of atherosclerosis and suggest that modulation of JMJD3 by CSE/H2S as a novel therapeutic option for treating atherosclerosis.

巨噬细胞表型在动脉粥样硬化发展中发挥重要角色；我们研究表明组蛋白H3K27去甲基化酶JMJD3对巨噬细胞炎症表型起促进作用，而胱硫醚-γ-裂解酶（CSE）/硫化氢（H2S）在心血管疾病和巨噬细胞表型中起积极作用。本项目首次探讨JMJD3在动脉粥样硬化免疫炎症作用及CSE/H2S调控作用：1)通过高脂诱导ApoE-/-小鼠动脉粥样硬化模型，结合慢病毒过表达/沉默JMJD3，检测动脉斑块形成、稳定性、M1/M2巨噬细胞比例、CSE/H2S等指标等，确定JMJD3促进动脉粥样硬化免疫炎症作用；2)进一步构建ApoE/CSE双敲除小鼠、慢病毒过表达CSE等，阐明CSE/H2S反馈性抑制JMJD3作用；3) 利用上述动物和细胞模型，揭示H2S通过硫巯化NF-κBp65 cysteine 38反馈性抑制JMJD3转录表达的新机制；为防治动脉粥样硬化提供新的理论依据。

巨噬细胞表型在动脉粥样硬化发展中发挥重要角色；我们研究表明组蛋白H3K27去甲基化酶JMJD3对巨噬细胞炎症表型起促进作用，而胱硫醚-γ-裂解酶（CSE）/硫化氢（H2S）在心血管疾病和巨噬细胞表型中起积极作用。本项目首次探讨JMJD3在动脉粥样硬化免疫炎症作用及CSE/H2S调控作用：1)通过高脂诱导ApoE-/-小鼠动脉粥样硬化模型，结合慢病毒过表达/沉默JMJD3，检测动脉斑块形成、稳定性、M1/M2巨噬细胞比例、CSE/H2S等指标等，确定JMJD3促进动脉粥样硬化免疫炎症作用；2)进一步构建ApoE/CSE双敲除小鼠、慢病毒过表达CSE等，阐明CSE/H2S反馈性抑制JMJD3作用；3) 利用上述动物和细胞模型，揭示H2S通过硫巯化NF-κBp65 cysteine 38反馈性抑制JMJD3转录表达的新机制；为防治动脉粥样硬化提供新的理论依据。