肠道菌群产物三甲胺诱导HepG2细胞产生氧化应激、炎症和凋亡

摘要/Abstract

摘要： 目的探讨三甲胺-N-氧化物(TMAO)的前体三甲胺(TMA)对肝细胞的影响。方法采用不同浓度(0、50、10 mmol/L)TMA处理HepG2细胞24 h和48 h,评估细胞活力、TMA向TMAO的转化及黄素单导氧化酶(FMO)基因表达。液相色谱串联质谱(LC-MS/MS)检测TMAO水平,油红O染色评估脂质沉积,DHE染色及ELISA分析氧化应激与炎症反应,流式细胞术及蛋白质印迹检测细胞凋亡。结果高浓度TMA显著降低HepG2细胞活力,TMA向TMAO的转化呈浓度和时间依赖性,伴随FMO1、FMO2和FMO3基因表达上调。尽管TMA本身对脂质代谢影响不大,但与脂肪酸共同作用时,可显著促进脂滴生成。同时,TMA诱导氧化应激、炎症反应及细胞凋亡。结论 TMA可能通过诱导氧化应激、炎症反应和细胞凋亡,间接加速非酒精性脂肪性肝病的进展。

关键词: 非酒精性脂肪性肝病, 三甲胺, 氧化三甲胺, 含黄素单氧化酶, 脂质代谢, 细胞凋亡

Abstract: Objective This study aims to evaluate the effects of TMA on hepatocytes. Methods HepG2 cells were treated with different concentrations (0, 50 μM, and 10 mM) of TMA for 24 and 48 hours. Cell viability, the conversion of TMA to TMAO, and the expression of flavin-containing monooxygenase (FMO) genes were assessed. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) were used to detect TMAO levels, while oil red O staining was used to evaluate lipid deposition. Oxidative stress and inflammatory responses were analyzed by DHE staining and ELISA. Cell apoptosis was detected by flow cytometry and western blotting (WB). Results High concentrations of TMA significantly reduced the viability of HepG2 cells in a dose- and time-dependent manner. The conversion of TMA to TMAO increased in a concentration-and time-dependent manner, accompanied by upregulation of FMO1, FMO2, and FMO3 gene expression. Although TMA itself did not significantly affect lipid metabolism, it significantly promoted lipid droplet formation when combined with fatty acids. Additionally, TMA induced oxidative stress, inflammation, and apoptosis in HepG2 cells. Conclusion TMA may indirectly accelerate the progression of non-alcoholic fatty liver disease (NAFLD) by inducing oxidative stress, inflammation, and apoptosis.

Key words: Non-alcoholic fatty liver disease, Trimethylamine, Trimethylamine-oxide, Flavin-containing mono-adducted oxidase, Lipid metabolism, Apoptosis

张秋令, 姚黎超, 佘莎, 戴锴, 李汛. 肠道菌群产物三甲胺诱导HepG2细胞产生氧化应激、炎症和凋亡[J]. 肝脏, 2026, 31(5): 711-717.

ZHANG Qiu-ling, YAO Li-chao, SHE Sha, DAI Kai, LI Xun. Gut microbiota-derived trimethylamine induces oxidative stress, inflammation, and apoptosis in HepG2 cells[J]. Chinese Hepatolgy, 2026, 31(5): 711-717.

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