Kumar Sonali, Shanker Ozasvi R, Parambath Sreestha Dinesh, Banerjee Jyotirmoy, Tripathi Manjari, Chandra P Sarat, Sharma M C, Lalwani Sanjeev, Siraj Fouzia, Dixit Aparna Banerjee
Dr. B. R. Ambedkar Centre for Biomedical Research, University of Delhi, Delhi, India.
Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India.
Exp Neurol. 2025 Oct;392:115367. doi: 10.1016/j.expneurol.2025.115367. Epub 2025 Jun 30.
Focal cortical dysplasia (FCD) is one of the most common causes of drug-resistant epilepsy (DRE) which is characterized by malformations of the cortex and molecular dysregulation. Despite advancements in classification and surgical interventions the pathophysiology behind it remains unclear and non-surgical treatment options remain limited. Oxidative stress, induced by imbalances of reactive oxygen species (ROS) and antioxidant defences, has been involved in the pathophysiology of FCD. This study evaluates the role of histone deacetylase 6 (HDAC6) in modulating oxidative stress and seizure activity through the acetylation status of peroxiredoxin-1 (Prdx1), a key antioxidant enzyme.
Cortical samples from FCD Type II patients and BCNU rat model were analysed using qRT-PCR, immunoblotting, and co-immunoprecipitation to assess the expression of HDAC6, and acetylation status of Prdx1. ROS levels were measured using dichlorofluorescin diacetate (DCFDA) assay. Pharmacological inhibition of HDAC6 using Tubastatin A (TubA) was evaluated for its effects on oxidative stress, Prdx1 acetylation, and seizure activity induced by pilocarpine.
HDAC6 was found to be significantly upregulated in the cortical samples from FCD Type II tissues and BCNU rats. Increased HDAC6 activity reduced Prdx1 acetylation, leading to elevated ROS levels and oxidative stress. TubA treatment restored Prdx1 acetylation, reduced oxidative stress, and significantly decreased seizure frequency and increased seizure latency in the BCNU model.
This study identifies HDAC6 as a key regulator of oxidative stress and epileptogenesis in FCD through Prdx1 deacetylation. Pharmacological inhibition of HDAC6 offers a promising therapeutic strategy for managing FCD-associated epilepsy by restoring antioxidant defences and mitigating seizure activity. Further studies are warranted to explore its clinical potential.
局灶性皮质发育不良(FCD)是药物难治性癫痫(DRE)最常见的病因之一,其特征为皮质畸形和分子调节异常。尽管在分类和手术干预方面取得了进展,但其背后的病理生理学仍不清楚,非手术治疗选择也仍然有限。活性氧(ROS)与抗氧化防御失衡所诱导的氧化应激已参与FCD的病理生理学过程。本研究通过关键抗氧化酶过氧化物酶1(Prdx1)的乙酰化状态,评估组蛋白去乙酰化酶6(HDAC6)在调节氧化应激和癫痫发作活动中的作用。
使用定量逆转录聚合酶链反应(qRT-PCR)、免疫印迹和免疫共沉淀分析II型FCD患者的皮质样本和卡氮芥(BCNU)大鼠模型,以评估HDAC6的表达及Prdx1的乙酰化状态。使用二氯荧光素二乙酸酯(DCFDA)测定法测量ROS水平。评估曲古抑菌素A(TubA)对HDAC6的药理学抑制作用,观察其对氧化应激、Prdx1乙酰化以及毛果芸香碱诱导的癫痫发作活动的影响。
发现HDAC6在II型FCD组织和BCNU大鼠的皮质样本中显著上调。HDAC6活性增加会降低Prdx1的乙酰化,导致ROS水平升高和氧化应激。TubA治疗可恢复Prdx1的乙酰化,减轻氧化应激,并显著降低BCNU模型中的癫痫发作频率,延长癫痫发作潜伏期。
本研究确定HDAC6是通过Prdx1去乙酰化调节FCD氧化应激和癫痫发生的关键调节因子。对HDAC6的药理学抑制通过恢复抗氧化防御和减轻癫痫发作活动,为治疗FCD相关癫痫提供了一种有前景的治疗策略。有必要进一步研究以探索其临床潜力。