Jiang Guannan, Zhou Jialei, Zhuang Yan, Yang Siyuan, Chen Gang, You Wanchun, Li Xiang
Department of Neurosurgery and Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, Suzhou, China.
Institute of Stroke Research, Soochow University, Suzhou, China.
CNS Neurosci Ther. 2025 Apr;31(4):e70373. doi: 10.1111/cns.70373.
Intracerebral hemorrhage (ICH) is a severe condition characterized by elevated mortality and disability rates. The cAMP-activated exchange protein-1 (EPAC-1) is implicated in various cytoprotective mechanisms; however, its specific role in ICH remains unclear.
A rat model of ICH was established by injecting autologous blood, while the in vitro primary neuronal model was stimulated using oxyhemoglobin (OxyHb). The construction of EPAC-1 overexpression wild-type (WT) and phosphorylated mutant plasmids (S108A or S108E), as well as lentiviruses, was performed for in vitro and in vivo studies.
The cAMP signaling pathway was found to be significantly enriched following ICH by high-throughput sequencing analysis. Our findings showed that while EPAC-1 protein levels remained relatively unchanged after ICH, RabGEF activity was conspicuously upregulated. This was accompanied by a marked decrease in EPAC-1 phosphorylation levels. Mutations that activate EPAC-1 phosphorylation led to significant improvements in neuronal survival and behavioral outcomes after ICH. Bioinformatics analysis revealed that ferroptosis was significantly enriched after ICH and showed a positive correlation with EPAC-1 serine phosphorylation. EPAC-1 phosphorylation activating mutations inhibit neuronal ferroptosis, whereas inactivating mutations exacerbate it.
The phosphorylation of EPAC-1 is essential for maintaining neuronal survival, which may be related to ferroptosis inhibition after ICH.
脑出血（ICH）是一种严重疾病，其死亡率和致残率较高。环磷酸腺苷（cAMP）激活的交换蛋白1（EPAC-1）参与多种细胞保护机制；然而，其在脑出血中的具体作用尚不清楚。
通过注射自体血建立大鼠脑出血模型，同时使用氧合血红蛋白（OxyHb）刺激体外原代神经元模型。构建EPAC-1过表达野生型（WT）和磷酸化突变体质粒（S108A或S108E）以及慢病毒，用于体外和体内研究。
通过高通量测序分析发现，脑出血后cAMP信号通路显著富集。我们的研究结果表明，脑出血后EPAC-1蛋白水平相对保持不变，而RabGEF活性明显上调。同时，EPAC-1磷酸化水平显著降低。激活EPAC-1磷酸化的突变导致脑出血后神经元存活率和行为结果显著改善。生物信息学分析显示，脑出血后铁死亡显著富集，且与EPAC-1丝氨酸磷酸化呈正相关。EPAC-1磷酸化激活突变抑制神经元铁死亡，而失活突变则使其加剧。
EPAC-1的磷酸化对于维持神经元存活至关重要，这可能与脑出血后抑制铁死亡有关。
