USP5 通过稳定 TXNIP 蛋白促进脂多糖诱导的细胞凋亡和炎症反应。

USP5 promotes lipopolysaccharide-induced apoptosis and inflammatory response by stabilizing the TXNIP protein.

机构信息

Department of Critical Care Medicine, Shengli Clinical Medical College of Fujian Medical University, Fujian Provincial Hospital South Branch, Fujian Provincial Hospital, Fuzhou, Fujian Province, China.

Department of Hepatobiliary and Pancreatic Surgery, Clinical Oncology School of Fujian Medical University, Fujian Cancer Hospital, Fuzhou, Fujian Province, China.

出版信息

Hepatol Commun. 2023 Aug 3;7(8). doi: 10.1097/HC9.0000000000000193. eCollection 2023 Aug 1.

DOI:10.1097/HC9.0000000000000193

PMID:37534934

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC10553006/

Abstract

BACKGROUND

The role of thioredoxin-interacting protein (TXNIP) in lipopolysaccharide-induced liver injury in mice has been reported, but the underlying mechanisms are poorly understood.

METHODS

We overexpressed deubiquitinase in cells overexpressing TXNIP and then detected the level of TXNIP to screen out the deubiquitinase regulating TXNIP; the interaction between TXNIP and deubiquitinase was verified by coimmunoprecipitation. After knockdown of a deubiquitinase and overexpression of TXNIP in Huh7 and HepG2 cells, lipopolysaccharide was used to establish a cellular inflammatory model to explore the role of deubiquitinase and TXNIP in hepatocyte inflammation.

RESULTS

In this study, we discovered that ubiquitin-specific protease 5 (USP5) interacts with TXNIP and stabilizes it through deubiquitylation in Huh-7 and HepG2 cells after treatment with lipopolysaccharide. In lipopolysaccharide-treated Huh-7 and HepG2 cells, USP5 knockdown increased cell viability, reduced apoptosis, and decreased the expression of inflammatory factors, including NLRP3, IL-1β, IL-18, ASC, and procaspase-1. Overexpression of TXNIP reversed the phenotype induced by knockdown USP5.

CONCLUSIONS

In summary, USP5 promotes lipopolysaccharide-induced apoptosis and inflammatory response by stabilizing the TXNIP protein.

摘要

背景

已有报道称，硫氧还蛋白相互作用蛋白（TXNIP）在脂多糖诱导的小鼠肝损伤中发挥作用，但其中的作用机制尚不清楚。

方法

我们在过表达 TXNIP 的细胞中过表达去泛素化酶，然后检测 TXNIP 的水平，以筛选出调节 TXNIP 的去泛素化酶；通过共免疫沉淀验证 TXNIP 与去泛素化酶之间的相互作用。在 Huh7 和 HepG2 细胞中敲低一种去泛素化酶并过表达 TXNIP 后，用脂多糖建立细胞炎症模型，以探讨去泛素化酶和 TXNIP 在肝细胞炎症中的作用。

结果

本研究发现，在脂多糖处理的 Huh-7 和 HepG2 细胞中，泛素特异性蛋白酶 5（USP5）通过去泛素化作用与 TXNIP 相互作用并使其稳定。在脂多糖处理的 Huh-7 和 HepG2 细胞中，USP5 敲低可增加细胞活力，减少细胞凋亡，并降低炎症因子（包括 NLRP3、IL-1β、IL-18、ASC 和 procaspase-1）的表达。TXNIP 的过表达逆转了 USP5 敲低引起的表型。