Guangxi Key Laboratory of Diabetic Systems Medicine & Institute of Basic Medical Sciences, Faculty of Basic Medical Sciences, Guilin Medical University, Guilin 541199, China.
Hunan Mingshun Pharmaceutical Co., Ltd., Shaodong 422800, China.
J Zhejiang Univ Sci B. 2023 Nov 15;24(11):998-1013. doi: 10.1631/jzus.B2200682.
This study aims to investigate the impact of hepatocyte nuclear factor 1β (HNF1b) on macrophage sortilin-mediated lipid metabolism and aortic atherosclerosis and explore the role of the flavone of (PAOA-flavone)-promoted small ubiquitin-related modifier (SUMO) modification in the atheroprotective efficacy of HNF1b. HNF1b was predicted to be a transcriptional regulator of sortilin expression via bioinformatics, dual-luciferase reporter gene assay, and chromatin immunoprecipitation. HNF1b overexpression decreased sortilin expression and cellular lipid contents in THP-1 macrophages, leading to a depression in atherosclerotic plaque formation in low-density lipoprotein (LDL) receptor-deficient (LDLR) mice. Multiple SUMO1-modified sites were identified on the HNF1b protein and co-immunoprecipitation confirmed its SUMO1 modification. The SUMOylation of HNF1b protein enhanced the HNF1b-inhibited effect on sortilin expression and reduced lipid contents in macrophages. PAOA-flavone treatment promoted SUMO-activating enzyme subunit 1 (SAE1) expression and SAE1-catalyzed SUMOylation of the HNF1b protein, which prevented sortilin-mediated lipid accumulation in macrophages and the formation of atherosclerotic plaques in apolipoprotein E-deficient (ApoE) mice. Interference with SAE1 abrogated the improvement in lipid metabolism in macrophage cells and atheroprotective efficacy in vivo upon PAOA-flavone administration. In summary, HNF1b transcriptionally suppressed sortilin expression and macrophage lipid accumulation to inhibit aortic lipid deposition and the development of atherosclerosis. This anti-atherosclerotic effect was enhanced by PAOA-flavone-facilitated, SAE1-catalyzed SUMOylation of the HNF1b protein.
本研究旨在探讨肝细胞核因子 1β（HNF1b）对巨噬细胞分选素介导的脂质代谢和主动脉粥样硬化的影响，并探索 HNF1b 促进小泛素相关修饰物（SUMO）修饰的 flavone of （PAOA-flavone）在其抗动脉粥样硬化作用中的作用。通过生物信息学、双荧光素酶报告基因检测和染色质免疫沉淀实验，预测 HNF1b 是分选素表达的转录调节因子。HNF1b 过表达可降低 THP-1 巨噬细胞中分选素的表达和细胞内脂质含量，导致载脂蛋白 E 缺陷（ApoE）小鼠低密度脂蛋白（LDL）受体缺陷（LDLR）小鼠动脉粥样硬化斑块形成减少。在 HNF1b 蛋白上鉴定到多个 SUMO1 修饰位点，并通过共免疫沉淀证实了其 SUMO1 修饰。HNF1b 蛋白的 SUMOylation 增强了 HNF1b 对分选素表达的抑制作用，并降低了巨噬细胞中的脂质含量。PAOA-flavone 处理可促进 SUMO 激活酶亚基 1（SAE1）的表达和 SAE1 催化的 HNF1b 蛋白 SUMOylation，从而防止巨噬细胞中分选素介导的脂质积累和载脂蛋白 E 缺陷（ApoE）小鼠动脉粥样硬化斑块的形成。干扰 SAE1 可阻断 PAOA-flavone 给药后巨噬细胞脂质代谢的改善和体内的抗动脉粥样硬化作用。综上所述，HNF1b 通过转录抑制分选素的表达和巨噬细胞的脂质积累，抑制主动脉脂质沉积和动脉粥样硬化的发展。这种抗动脉粥样硬化作用通过 PAOA-flavone 促进的、SAE1 催化的 HNF1b 蛋白 SUMOylation 得到增强。
