Department of Cardiology, Jiangxi Provincial People's Hospital, Nanchang, Jiangxi 330006, P.R. China.
Department of Internal Medicine, Shanggao Hospital of Traditional Chinese Medicine, Yichun, Jiangxi 336400, P.R. China.
Mol Med Rep. 2019 Jun;19(6):4973-4979. doi: 10.3892/mmr.2019.10161. Epub 2019 Apr 12.
Atherosclerosis is a chronic and progressive disease. Its morbidity and mortality rates have demonstrated an increase in recent years. The present study aimed to explore the role of sirtuin (SIRT) 4 in the development of atherosclerosis. Alterations in SIRT4 expression in response to oxidized low density lipoprotein (oxLDL) were quantified in human umbilical vein endothelial cells (HUVECs) using western blotting. Cell counting kit‑8 and flow cytometry assays were used in order to explore the effects of SIRT4 on HUVEC proliferation and apoptosis. The effect of SIRT4 on the expression of inflammatory factors in HUVECs was analyzed using ELISA. The expression and phosphorylation of proteins in the phosphoinositide 3‑kinase (PI3K)/protein kinase B (Akt)/nuclear factor (NF)‑κB pathway were comparatively analyzed using western blotting. Nuclear translocation of p65 NF‑κB was examined using immunofluorescence. The present study indicated that oxLDL treatment decreased the expression of SIRT4 in HUVECs in a dose‑ and time‑dependent manner. SIRT4 overexpression promoted oxLDL‑induced HUVEC proliferation and inhibited cell apoptosis. Furthermore, SIRT4 overexpression suppressed the PI3K/Akt/NF‑κB pathway by inhibiting PI3K phosphorylation and phosphorylated (p)‑Akt, p‑nuclear factor of kappa light polypeptide gene enhancer in B‑cells inhibitor α and p‑p65 NF‑κB expression; blocking p65 NF‑κB nuclear translocation and decreasing interleukin (IL)‑1β, IL‑6, and tumor necrosis factor α expression in oxLDL‑induced HUVECs. In conclusion, SIRT4 overexpression enhanced HUVEC survival, suppressed the PI3K/Akt/NF‑κB signaling pathway and inhibited the expression of inflammatory cytokines in oxLDL‑induced HUVECs.
动脉粥样硬化是一种慢性进行性疾病。近年来,其发病率和死亡率呈上升趋势。本研究旨在探讨沉默信息调节因子 4(SIRT4)在动脉粥样硬化发展中的作用。采用 Western blot 法检测人脐静脉内皮细胞(HUVEC)中氧化型低密度脂蛋白(oxLDL)作用下 SIRT4 表达的变化。细胞计数试剂盒-8 和流式细胞术检测 SIRT4 对 HUVEC 增殖和凋亡的影响。ELISA 法分析 SIRT4 对 HUVEC 中炎症因子表达的影响。Western blot 法比较分析 SIRT4 对磷酸肌醇 3-激酶(PI3K)/蛋白激酶 B(Akt)/核因子(NF)-κB 通路中蛋白表达和磷酸化的影响。免疫荧光法检测 p65 NF-κB 的核转位。本研究表明,oxLDL 处理呈剂量和时间依赖性地下调 HUVEC 中 SIRT4 的表达。SIRT4 过表达促进 oxLDL 诱导的 HUVEC 增殖,抑制细胞凋亡。此外,SIRT4 过表达通过抑制 PI3K 磷酸化和磷酸化(p)-Akt、p-核因子κB 抑制亚基抑制 PI3K/Akt/NF-κB 通路α和 p-p65 NF-κB 的表达;阻断 p65 NF-κB 核转位,减少 oxLDL 诱导的 HUVEC 中白细胞介素(IL)-1β、IL-6 和肿瘤坏死因子α的表达。综上所述,SIRT4 过表达增强了 HUVEC 的存活,抑制了 oxLDL 诱导的 HUVEC 中 PI3K/Akt/NF-κB 信号通路和炎症细胞因子的表达。