GATA-4 regulates neuronal apoptosis after intracerebral hemorrhage via the NF-κB/Bax/Caspase-3 pathway both in vivo and in vitro（GATA-4调节脑出血后神经元凋亡）

Hui Xu  ¹ , Jie Cao  ² , Jianguo Xu  ³ , Haiying Li  ³ , Haitao Shen  ³ , Xiang Li  ³ , Zhong Wang  ³ , Jiang Wu  ⁴ , Gang Chen  ³

• ¹ Department of Neurosurgery & Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou 215006, Jiangsu Province, China; Department of Neurosurgery, The Sixth People’s Hospital of Nantong, No. 500 Yonghe Road, Nantong 226011, Jiangsu Province, China.
• ² Department of Neurosurgery & Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou 215006, Jiangsu Province, China; Department of Neurosurgery, The First People’s Hospital of Changzhou, Juqian Street, Changzhou 213003, Jiangsu Province, China.
• ³ Department of Neurosurgery & Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou 215006, Jiangsu Province, China.
• ⁴ Department of Neurosurgery & Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou 215006, Jiangsu Province, China. Electronic address: wujiangsz@163.com.

Abstract

GATA-binding protein 4 (GATA-4)，a member of the GATA family of transcription factors, is expressed in the normal brain and participates in the neural inflammatory response and senescence. However, few studies have investigated whether GATA-4 is involved in the brain damage induced by intracerebral hemorrhage (ICH). The aim of this study was to investigate in vivo and in vitro the role of GATA-4 in ICH-induced secondary brain injury (SBI) and its potential underlying mechanisms. A rat model of ICH was established by autologous blood injection in vivo. In vitro, oxidized hemoglobin was applied to mimic the effects of ICH in neuronal culture. The function of GATA-4 and its mechanism of action after ICH were investigated using siRNA-mediated knockdown and plasmid-mediated overexpression techniques combined with immunofluorescence, western blot, and other molecular methods. It was found that the expression of GATA-4 was increased in the brain of rats after ICH, and its phosphorylation also increased correspondingly. Furthermore, knocking down the expression of GATA-4 led to a significant decrease in neurobehavioral scores and neuronal apoptosis, indicating that secondary brain damage was improved. Conversely, the overexpression of GATA-4 aggravated brain damage. Blockade of a critical phosphorylation site on the GATA-4 overexpression plasmid alleviated the exacerbated damage in vitro and in vivo. Moreover, GATA-4 promoted the activation of NF-κB, and increased the expression of Bax, and cysteine aspartate-specific protease 3 (caspase-3) in its cleaved form, causing neuronal apoptosis. In conclusion, the expression of GATA-4 was increased in the brain of rats after ICH. GATA-4 phosphorylation mediates the function of the protein in ICH-induced SBI. Neuronal apoptosis after ICH was mainly induced by NF-κB activation, which was promoted by GATA-4.

Keywords: Apoptosis; Bax; Caspase-3; GATA-4; Intracerebral hemorrhage; NF-κB.