The First Affiliated Hospital, Department of Ultrasound Medicine, Hengyang Medical School, University of South China, Hengyang, Hunan 421001, China.
The First Affiliated Hospital, Department of Cardiothoracic Surgery, Hengyang Medical School, University of South China, Hengyang, Hunan 421001, China.
Epigenetics. 2023 Dec;18(1):2239592. doi: 10.1080/15592294.2023.2239592.
Nonalcoholic fatty liver disease (NAFLD) is the most common hepatic disorders worldwide. The mitophagy is suggested to be repressed in NAFLD, but the mechanism remains to be elucidated.
NAFLD cell and mouse models were established by treating with free fatty acid (FFA) and feeding a high fat diet (HFD), respectively. QRT-PCR, Western blotting, or IHC measured the expression of ZNF143, lncRNA NEAT1, ROCK2, and lipid formation/mitophagy-related proteins. Cell viability and mitophagy were evaluated by MTT and immunofluorescence. The chloroform-methanol extraction method measured triglyceride and total cholesterol levels. ELISA detected ALT and AST levels. The interactions among ZNF143, lncRNA NEAT1 and SND1 were analysed by ChIP, dual-luciferase reporter, pull-down, and RIP. The lipid droplets were determined by Oil-red O and HE staining.
ZNF143 and lncRNA NEAT1 were upregulated in hepatic cells treated with FFA ( < 0.01 and < 0.001). Knockdown of ZNF143 or lncRNA NEAT1 inhibited lipid droplets formation, while promoting mitophagy ( < 0.01 and < 0.001). ZNF143 promoted lncRNA NEAT1 transcriptional expression through binding to its promoter. LncRNA NEAT1 increased ROCK2 mRNA stability by targeting SND1. LncRNA NEAT1 or ROCK2 overexpression reversed the effect of ZNF143 or lncRNA NEAT1 knockdown on hepatic steatosis and mitophagy ( < 0.01 and < 0.001). ZNF143 or lncRNA NEAT1 knockdown inhibited HFD-induced steatosis and promoted mitophagy ( < 0.01 and < 0.001).
The upregulation of lncRNA NEAT1 caused by ZNF143 promoted NAFLD through inhibiting mitophagy via activating ROCK2 pathway by targeting SND1, providing potential targets for NAFLD therapy.
非酒精性脂肪性肝病（NAFLD）是全球最常见的肝脏疾病。有研究表明自噬在 NAFLD 中受到抑制，但具体机制尚不清楚。
通过用游离脂肪酸（FFA）处理和高脂饮食（HFD）喂养分别建立 NAFLD 细胞和小鼠模型。用 QRT-PCR、Western blot 或 IHC 检测 ZNF143、lncRNA NEAT1、ROCK2 和脂质形成/自噬相关蛋白的表达。用 MTT 和免疫荧光评估细胞活力和自噬。用氯仿-甲醇提取法测量甘油三酯和总胆固醇水平。用 ELISA 检测 ALT 和 AST 水平。用 ChIP、双荧光素酶报告基因、下拉和 RIP 分析 ZNF143、lncRNA NEAT1 和 SND1 之间的相互作用。用油红 O 和 HE 染色检测脂滴。
FFA 处理的肝细胞中 ZNF143 和 lncRNA NEAT1 表达上调（<0.01 和 <0.001）。敲低 ZNF143 或 lncRNA NEAT1 抑制脂滴形成，同时促进自噬（<0.01 和 <0.001）。ZNF143 通过结合其启动子促进 lncRNA NEAT1 的转录表达。lncRNA NEAT1 通过靶向 SND1 增加 ROCK2 mRNA 的稳定性。lncRNA NEAT1 或 ROCK2 的过表达逆转了 ZNF143 或 lncRNA NEAT1 敲低对肝脂肪变性和自噬的影响（<0.01 和 <0.001）。ZNF143 或 lncRNA NEAT1 敲低抑制 HFD 诱导的脂肪变性并促进自噬（<0.01 和 <0.001）。
由 ZNF143 引起的 lncRNA NEAT1 的上调通过靶向 SND1 激活 ROCK2 通路抑制自噬，促进 NAFLD 的发生，为 NAFLD 的治疗提供了潜在靶点。
