Effects of dietary alpha-linolenic acid on SUDEP, seizures, and neural structure and function in mouse models of epilepsy

项目总结 目前可用的药物无法控制约30%的癫痫患者的癫痫发作。这是一次严重的医疗事故 问题是因为患有严重进展性耐药癫痫的患者有很高的突发风险 癫痫意外死亡(SUDEP)。因此，需要新的和有效的预防战略 癫痫的治疗迫在眉睫。在可能的辅助治疗中，这种难治性的形式 癫痫，基于饮食的方法有很大的前景，因为它们通常是经济的，而且很少与广告相关。 反面副作用。我们的长期目标是为开发新技术提供必要的科学基础 对抗耐药癫痫的有效干预措施。为此，有必要澄清 通过改变饮食减少癫痫发作和SUDEP的分子和细胞机制。这个 这一探索性项目的总体目标是确定1)饮食的有益影响 小鼠补充-3多不饱和脂肪酸---亚麻酸 癫痫模型，以及2)“治疗性饮食”如何影响大脑的形态和生理功能 与癫痫有关的神经元。我们的中心假设是口服丙氨酸和牛奶乳清 通过诱导形态和生理改变降低癫痫小鼠模型的表型严重程度 在大脑的GABA能神经元中。这一假设部分是基于我们对果蝇和果蝇的初步发现 小鼠：1)补充牛奶乳清显著抑制神经和行为 果蝇的高兴奋性，以及癫痫小鼠的自发性癫痫发作和SUDEP，以及2)丙氨酸在 乳清介导了这种饮食诱导的对果蝇癫痫发作的抑制。当前项目将使用鼠标 电压门控钠通道突变体，已建立的人类癫痫模型。目标1是确定 丙氨酸对SUDEP和癫痫发作的影响建立Dravet综合征(Scn1aR1407X/+)和早期婴儿模型的小鼠 癫痫脑病(Scn8aN1768D/+)在脱机后每天给予ALA，自发性癫痫发作和 SUDEP将在持续的视频监控下进行监控。体温过高引起的癫痫也会 在有或没有ALA喂养的情况下对频率和严重程度进行评分。目标2是描绘饮食-- 诱导大脑神经元的形态和生理变化。牛奶、乳清和丙氨酸对小鼠生长发育的影响 新皮质GABA能中间神经元的形态将通过检查它们的数量、树突 Scn1aR1407X/+突变体的复杂性、轴突投射和末端密度。治疗性饮食的作用 GABA能神经元的功能也将通过来自新皮质的膜片钳记录来确定 切片。这项拟议的研究意义重大，因为它有望确定饮食的有益影响 在良好控制条件下对小鼠遗传性癫痫模型的修改，以及在 由饮食诱导的大脑神经元。这些成果为今后的研究奠定了坚实基础 改良饮食预防癫痫的分子和细胞机制。

PROJECT SUMMARY Currently available medications fail to control seizures in ~30% of epilepsy patients. This is a serious medical problem because patients with severe progressive forms of drug-resistant epilepsy have a high risk of sudden unexpected death in epilepsy (SUDEP). Thus, the need for novel and effective strategies for the prevention and treatment of epilepsy is pressing. Among the potential adjunctive therapies for such refractory forms of epilepsy, diet-based approaches hold great promise as they are often economical and associated with few ad- verse side effects. Our long-term goal is to provide the scientific foundation necessary for developing new effective interventions for combating drug-resistant epilepsy. To this end, it will be necessary to elucidate the molecular and cellular mechanisms through which dietary modifications reduce seizures and SUDEP. The overall objectives of this exploratory project are to determine 1) the beneficial effects of dietary supplementation with -linolenic acid (ALA), an essential -3 polyunsaturated fatty acid (PUFA), on mouse models of epilepsy, and 2) how “therapeutic diets” affect the morphology and physiological function of brain neurons that are relevant to epilepsy. Our central hypothesis is that orally administered ALA and milk whey reduce phenotypic severity in mouse models of epilepsy by inducing morphological and physiological changes in brain GABAergic neurons. This hypothesis is based, in part, on our preliminary findings in fruit flies and mice: 1) supplementation of diets with milk whey significantly suppresses neuronal and behavioral hyperexcitability in Drosophila, as well as spontaneous seizures and SUDEP in epileptic mice, and 2) ALA in milk whey mediates this diet-induced suppression of seizures in Drosophila. The current project will use mouse voltage-gated sodium channel mutants, well-established models of human epilepsy. Aim #1 is to determine the effects of ALA on SUDEP and seizures. Mice that model Dravet syndrome (Scn1aR1407X/+) and early infantile epileptic encephalopathy (Scn8aN1768D/+) will be fed ALA daily after weaning, and spontaneous seizures and SUDEP will be monitored under continuous video surveillance. Hyperthermia-induced seizures will also be scored for frequency and severity in the presence or absence of ALA feeding. Aim #2 is to delineate diet- induced morphological and physiological alterations in brain neurons. The effects of milk whey and ALA on the morphology of neocortical GABAergic interneurons will be assessed by examining their numbers, dendritic complexity, axonal projections, and terminal density in Scn1aR1407X/+ mutants. The effects of therapeutic diets on the function of GABAergic neurons will also be determined, by patch clamp recordings from neocortical slices. The proposed research is significant because it is expected to identify the beneficial effects of dietary modifications on mouse models of genetic epilepsy under well-controlled conditions, as well as the changes in brain neurons that are induced by diet. These outcomes represent a solid foundation for future studies of the molecular and cellular mechanisms by which modified diets protect against epilepsy.