Ghosh Chaitali, Westcott Rosemary, Skvasik David, Khurana Ishant, Khoury Jean, Blumcke Ingmar, El-Osta Assam, Najm Imad M
Cleveland Clinic.
Baker IDI Heart and Diabetes Institute.
Res Sq. 2024 Oct 17:rs.3.rs-4946501. doi: 10.21203/rs.3.rs-4946501/v1.
Focal cortical dysplasia (FCD) is recognized as a significant etiological factor in pharmacoresistant intractable epilepsy, linked with disturbances in neurovascular metabolism. Our study investigated regulation of glucose-transporter1 (GLUT1) and cerebral hypometabolism within FCD subtypes. Surgically excised human brain specimens underwent histopathological categorization. A subset of samples (paired with matching blood) was assessed for DNA methylation changes of glucose metabolism-related genes. We evaluated GLUT1, VEGFα, MCT2, and mTOR expression by western blot analysis, measured glucose-lactate concentrations, and established correlations with patients' demographic and clinical profiles. Furthermore, we investigated the impact of DNA methylation inhibitor decitabine and hypometabolic condition on the uptake of [H]-2-deoxyglucose and ATPase in epileptic brain endothelial cells (EPI-EC). We observed hypermethylation of GLUT1 and glucose metabolic genes in FCD brain/blood samples and could distinguish FCDIIa/b from mMCD, MOGHE and non-lesional types in brain. Low GLUT1 and glucose-lactate ratios corresponded to elevated VEGFα and MCT2 in FCDIIa/b vs non-lesional tissues, independent of age, gender, seizure-onset, or duration of epilepsy. Increased mTOR signaling in FCDIIa/b tissues was evident. Decitabine stimulation increased GLUT1, decreased VEGFα expression, restored glucose uptake and ATPase activity in EPI-ECs and reduced mTOR and MCT2 levels in HEK cells. We demonstrated: 1) hypermethylation of glucose regulatory genes distinguish FCDIIa/b from mMCD, MOGHE and non-lesional types, 2) glucose uptake reduction is due to GLUT1 suppression mediated possibly by a GLUT1-mTOR mechanism; and 3) DNA methylation regulates cellular glucose update and metabolism. Together, these studies may lead to GLUT1-mediated biomarkers, glucose metabolism and identify early intervention strategies in FCD.
局灶性皮质发育不良（FCD）被认为是药物难治性顽固性癫痫的一个重要病因，与神经血管代谢紊乱有关。我们的研究调查了FCD亚型中葡萄糖转运蛋白1（GLUT1）的调节和脑代谢减退情况。对手术切除的人脑标本进行组织病理学分类。对一部分样本（与匹配的血液配对）评估葡萄糖代谢相关基因的DNA甲基化变化。我们通过蛋白质印迹分析评估GLUT1、VEGFα、MCT2和mTOR的表达，测量葡萄糖 - 乳酸浓度，并建立与患者人口统计学和临床特征的相关性。此外，我们研究了DNA甲基化抑制剂地西他滨和代谢减退状态对癫痫性脑内皮细胞（EPI - EC）中[H] - 2 - 脱氧葡萄糖摄取和ATP酶的影响。我们观察到FCD脑/血样本中GLUT1和葡萄糖代谢基因的高甲基化，并且可以在脑中区分FCDIIa/b与微小发育不良性皮质病变（mMCD）、局灶性多小脑回畸形（MOGHE）和非病变类型。与非病变组织相比，FCDIIa/b中低GLUT1和葡萄糖 - 乳酸比值与升高的VEGFα和MCT2相对应，与年龄、性别、癫痫发作起始或癫痫持续时间无关。FCDIIa/b组织中mTOR信号传导增加是明显的。地西他滨刺激增加了GLUT1，降低了VEGFα表达，恢复了EPI - EC中的葡萄糖摄取和ATP酶活性，并降低了HEK细胞中的mTOR和MCT2水平。我们证明：1）葡萄糖调节基因的高甲基化将FCDIIa/b与mMCD、MOGHE和非病变类型区分开来；2）葡萄糖摄取减少是由于可能由GLUT1 - mTOR机制介导的GLUT1抑制；3）DNA甲基化调节细胞葡萄糖摄取和代谢。总之，这些研究可能会产生GLUT1介导的生物标志物、葡萄糖代谢，并确定FCD的早期干预策略。
