Department of Pharmacology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran; Division of Neurocognitive Sciences, Psychiatry and Behavioral Sciences Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.
Neuroscience Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.
Life Sci. 2021 Nov 1;284:119923. doi: 10.1016/j.lfs.2021.119923. Epub 2021 Sep 2.
Levetiracetam (LEV) is a broad-spectrum antiepileptic drug with neuroprotective properties and novel mechanisms of action. Some evidence suggests that LEV may impact adult neurogenesis, but the results are controversial. The present study was aimed to evaluate the effects of LEV on the proliferation and differentiation of rat embryonic neural stem cells (NSCs) and to explore the role of GABA or NMDA receptors.
NSCs were isolated from rat fetal ganglionic eminence at embryonic day 14.5. The effects of LEV on viability, proliferation, neurosphere formation, and neuronal or astroglial differentiation of NSCs were assessed using resazurin, BrdU incorporation, immunocytochemistry, quantitative real-time PCR, and western blotting. Additionally, we addressed the relationship between treatment with NMDA and GABA receptor antagonists (MK801 and saclofen, respectively) in combination with LEV on these parameters.
The data showed that LEV (50 μM) significantly increased the number (p < 0.01) and diameter of neurospheres (p < 0.05), enhanced proliferation (p < 0.01), and promoted neuronal differentiation, as revealed by significantly increased expressions of DCX and NeuN. The expressions of astroglial markers, GFAP and Olig2, were markedly reduced. The addition of MK801 (10 μM) significantly diminished neurospheres growth (p < 0.001), decreased the number of proliferating cells (p < 0.01), and reduced the number of new neurons (p < 0.001) but increased the astroglial cells (p < 0.001) induced by LEV. Co-treatment with saclofen (25 μM) did not significantly affect LEV-induced NSCs proliferation and differentiation.
Our findings suggest that LEV may enhance rat embryonic neurogenesis mainly through an NMDA receptor-mediated mechanism.
左乙拉西坦（LEV）是一种具有神经保护作用和新型作用机制的广谱抗癫痫药物。有证据表明，LEV 可能影响成年神经发生，但结果存在争议。本研究旨在评估 LEV 对大鼠胚胎神经干细胞（NSC）增殖和分化的影响，并探讨 GABA 或 NMDA 受体的作用。
从胚胎第 14.5 天的大鼠胎神经节隆起中分离 NSCs。使用 Resazurin、BrdU 掺入、免疫细胞化学、实时定量 PCR 和 Western blot 评估 LEV 对 NSCs 活力、增殖、神经球形成以及神经元或星形胶质细胞分化的影响。此外，我们还研究了 NMDA 和 GABA 受体拮抗剂（MK801 和 saclofen）分别与 LEV 联合处理对这些参数的关系。
数据表明，LEV（50 μM）显著增加了神经球的数量（p<0.01）和直径（p<0.05），增强了增殖（p<0.01），并促进了神经元分化，表现为 DCX 和 NeuN 的表达显著增加。星形胶质细胞标志物 GFAP 和 Olig2 的表达明显减少。添加 MK801（10 μM）显著降低了神经球的生长（p<0.001），减少了增殖细胞的数量（p<0.01），并减少了新神经元的数量（p<0.001），但增加了 LEV 诱导的星形胶质细胞（p<0.001）。与 saclofen（25 μM）共同处理对 LEV 诱导的 NSCs 增殖和分化没有显著影响。
我们的发现表明，LEV 可能主要通过 NMDA 受体介导的机制增强大鼠胚胎神经发生。
