ERK/CT-1通路对氧化应激致H9C2细胞凋亡的影响

Role of ERK/CT-1 pathway in oxidative stress-induced H9C2 cell apoptosis

摘要:

目的 观察在氧化应激情况下心肌营养因子-1（CT-1）的表达情况及其对心肌细胞凋亡的影响，探讨其相关机制。方法 以过氧化氢刺激H9C2细胞建立氧化损伤模型，N-乙酰半胱氨酸或CT-1小干扰RNA（siRNA）与过氧化氢共同孵育以确定活性氧类（ROS）对CT-1表达的影响，以及CT-1在细胞凋亡中的作用。以丝裂原活化细胞外信号调节激酶（MEK/ERK）特异性抑制剂PD98059预处理H9C2细胞，以确定过氧化氢诱导CT-1表达的机制。结果 过氧化氢可剂量依赖性地诱导CT-1的过表达，N-乙酰半胱氨酸可显著抑制过氧化氢诱导的CT-1过表达。过氧化氢诱导的H9C2细胞凋亡可被N-乙酰半胱氨酸阻断，但CT-1 siRNA可加重过氧化氢诱导的H9C2细胞凋亡。过氧化氢可剂量依赖性地促进ERK的活化，PD98059预处理明显抑制过氧化氢诱导的CT-1上调。结论 过氧化氢能活化ERK/CT-1通路，从而缓解氧化应激引起的细胞凋亡。

Abstract:

Objective To examine the expression profile of cardiotrophin-1 (CT-1) in oxidative stress challenged H9C2 cells and potential role of ERK/CT-1 signal pathway in this pathological procedure. Methods H9C2 cell model of oxidative stress was established by coincubation with hydrogen peroxide. N-acetylcysteine or CT-1 siRNA was incubated to determine the effect of reactive oxygen species (ROS) on CT-1 expression and apoptosis. Mitogen-activated extracellular signal-regulated kinase (MEK/ERK) specific inhibitor PD98059 was utilized to determine the probable mechanisms. Results Hydrogen peroxide induced a dose-dependent increasing of CT-1 expression, which was significantly attenuated by N-acetylcysteine. H9C2 cell apoptosis was inhibited by N-acetylcysteine treatment but was accelerated by CT-1 siRNA. Hydrogen peroxide dose promoted the activation of ERK signal pathway, while pretreatment with PD98059 significantly inhibited Hydrogen peroxide -induced upregulated expression of CT-1. Conclusions Hydrogen peroxide alleviates cell apoptosis probably through activation of ERK/CT-1 pathway.