Department of Pathology, Peking University, Shenzhen Hospital, Shenzhen, Guangdong 518001, P.R. China.
Department of Pathology, Fudan University Affiliated Zhongshan Hospital, Shanghai 200032, P.R. China.
Mol Med Rep. 2017 Nov;16(5):6088-6093. doi: 10.3892/mmr.2017.7358. Epub 2017 Aug 24.
CCAAT enhancer binding protein‑α (C/EBP‑α) is a transcription factor expressed only in certain tissues, including the liver. It has been previously demonstrated that C/EBP‑α may induce apoptosis in hepatic stellate cells (HSCs), raising the question of whether acetylation of C/EBP‑α is associated with HSCs, and the potential associated mechanism. A total of three histone deacetylase inhibitors (HDACIs), including trichostatin A (TSA), suberoylanilide hydroxamic acid and nicotinamide, were selected to determine whether acetylation affects C/EBP‑α expression. A Cell Counting Kit‑8 assay was used to determine the rate of proliferation inhibition following treatment with varying doses of the three HDACIs in HSC‑T6 and BRL‑3A cells. Western blot analysis was used to examine Caspase‑3, ‑8, ‑9, and ‑12 levels in HSC‑T6 cells treated with adenoviral‑C/EBP‑α and/or TSA. Following treatment with TSA, a combination of reverse transcription‑quantitative polymerase chain reaction and western blot analyses was used to determine the inherent C/EBP‑α mRNA and protein levels in HSC‑T6 cells at 0, 1, 2, 4, 8, 12, 24, 36 and 48 h. Nuclear and cytoplasmic proteins were extracted to examine C/EBP‑α distribution. Co‑immunoprecipitation analysis was used to examine the lysine acetylation of C/EBP‑α. It was observed that TSA inhibited the proliferation of HSC‑T6 cells to a greater extent compared with BRL‑3A cells, following treatment with the three HDACIs. TSA induced apoptosis in HSC‑T6 cells and enhanced the expression of C/EBP‑α. Following treatment of HSC‑T6 cells with TSA, inherent C/EBP‑α expression increased in a time‑dependent manner, and its lysine acetylation simultaneously increased. Therefore, the results of the present study suggested that TSA may increase C/EBP‑α expression by increasing its lysine acetylation in HSCs.
CCAAT 增强子结合蛋白-α(C/EBP-α)是一种仅在特定组织中表达的转录因子,包括肝脏。先前已经证明,C/EBP-α 可能诱导肝星状细胞(HSCs)凋亡,这就提出了一个问题,即 C/EBP-α 的乙酰化是否与 HSCs 相关,以及潜在的相关机制。本研究选择了三种组蛋白去乙酰化酶抑制剂(HDACIs),包括曲古抑菌素 A(TSA)、丁酸钠和烟酰胺,以确定乙酰化是否会影响 C/EBP-α 的表达。采用细胞计数试剂盒-8 检测三种 HDACIs 处理 HSC-T6 和 BRL-3A 细胞后增殖抑制率。采用 Western blot 分析检测腺病毒-C/EBP-α 和/或 TSA 处理的 HSC-T6 细胞中 Caspase-3、-8、-9 和 -12 的水平。用 TSA 处理后,采用逆转录-定量聚合酶链反应和 Western blot 分析相结合的方法,在 0、1、2、4、8、12、24、36 和 48 h 时检测 HSC-T6 细胞中固有 C/EBP-α mRNA 和蛋白水平。提取核和细胞质蛋白以检测 C/EBP-α 的分布。采用免疫共沉淀分析检测 C/EBP-α 的赖氨酸乙酰化。结果发现,与 BRL-3A 细胞相比,三种 HDACIs 处理后 TSA 对 HSC-T6 细胞的增殖抑制作用更大。TSA 诱导 HSC-T6 细胞凋亡,并增强 C/EBP-α 的表达。用 TSA 处理 HSC-T6 细胞后,固有 C/EBP-α 的表达呈时间依赖性增加,其赖氨酸乙酰化同时增加。因此,本研究结果表明,TSA 可能通过增加 HSCs 中 C/EBP-α 的赖氨酸乙酰化来增加其表达。