Zhu Pingping, Yuan Wei, Liu Wenquan, Wu Jian, Wang Pengzhen, Ning Bo
Department of Neurology, Guangzhou Red Cross Hospital, Jinan University, Guangzhou, China.
Department of General Surgery, Guangzhou Red Cross Hospital, Jinan University, Guangzhou, China.
Cytojournal. 2024 Nov 28;21:57. doi: 10.25259/Cytojournal_53_2024. eCollection 2024.
Potassium voltage-gated channel sub-family A member 1 (Kv1.1), as a shaker homolog potassium channel, displays a special mechanism for posttranscriptional regulation called RNA editing. Adenosine deaminase acting on RNA 2 (ADAR2) can cause abnormal editing or loss of normal editing, which results in cell damage and related diseases. The relationship between Kv1.1 and editing enzyme ADAR2 in epileptic rats remains incompletely understood. We aimed to investigate the neuroprotective role of ADAR2 and its relationship with Kv1.1 in epileptic rats and the SH-SY5Y neuroblastoma cell line.
A rat epilepsy model was induced using lithium chloride-pilocarpine. We investigated the effect of ADAR2 on epileptic rats through Western blotting, quantitative reverse transcription polymerase chain reaction (qRT-PCR), and histological analysis. Western blotting was aimed at investigating the effect of overexpression of ADAR2 and Kv1.1-interfering RNA (si-Kv1.1) for neuronal apoptosis.
The overexpression of ADAR2 in epileptic rats led to the increased mRNA and protein expression of Kv1.1 ( < 0.001) and B-cell leukemia/lymphoma 2 protein (Bcl-2) ( < 0.001), whereas the decreased expressions of Bcl-2-associated X protein and cleaved caspases-3/7 at protein levels ( < 0.0001; < 0.0001; < 0.01) detected by Western blotting and qRT-PCR experiments. Hematoxylin and eosin staining and Nissl staining revealed the neuroprotection provided by ADAR2 overexpression. The experiments demonstrated that Kv1.1 was regulated by ADAR2. ADAR2 overexpression increased neuronal survival in experiments through the elevation of Bcl-2 levels ( < 0.05) and reduction of cleaved caspase-3/7 activity ( < 0.0001; < 0.01). In the recovery experimental group that involved silencing Kv1.1, the beneficial effects of overexpressing ADAR2 were no longer observed ( < 0.05).
Our findings confirm that the upregulation of ADAR2 promotes Kv1.1 protein expression, which ultimately reduces neuronal damage in the hippocampus of animals with epilepsy.
钾离子电压门控通道亚家族A成员1（Kv1.1）作为一种震颤同源钾通道，具有一种称为RNA编辑的特殊转录后调控机制。作用于RNA的腺苷脱氨酶2（ADAR2）可导致异常编辑或正常编辑缺失，进而导致细胞损伤及相关疾病。癫痫大鼠中Kv1.1与编辑酶ADAR2之间的关系仍未完全明确。我们旨在研究ADAR2在癫痫大鼠及SH-SY5Y神经母细胞瘤细胞系中的神经保护作用及其与Kv1.1的关系。
采用氯化锂-匹鲁卡品诱导建立大鼠癫痫模型。我们通过蛋白质免疫印迹法、定量逆转录聚合酶链反应（qRT-PCR）和组织学分析来研究ADAR2对癫痫大鼠的影响。蛋白质免疫印迹法旨在研究ADAR2过表达和Kv1.1干扰RNA（si-Kv1.1）对神经元凋亡的影响。
癫痫大鼠中ADAR2过表达导致Kv1.1的mRNA和蛋白表达增加（<0.001）以及B细胞淋巴瘤/白血病-2蛋白（Bcl-2）表达增加（<0.0,01），而蛋白质免疫印迹法和qRT-PCR实验检测到Bcl-2相关X蛋白和裂解的半胱天冬酶-3/7在蛋白水平的表达降低（<0.0001；<0.0001；<0.01）。苏木精-伊红染色和尼氏染色显示ADAR2过表达具有神经保护作用。实验表明Kv1.1受ADAR2调控。ADAR2过表达通过提高Bcl-2水平（<0.05）和降低裂解的半胱天冬酶-3/7活性（<0.0001；<0.01）增加了实验中的神经元存活率。在涉及沉默Kv1.1的恢复实验组中，未再观察到ADAR2过表达的有益作用（<0.05）。
我们的研究结果证实，ADAR2上调可促进Kv1.1蛋白表达，最终减少癫痫动物海马体中的神经元损伤。
