Oxidative Stress and the Ketogenic Diet

描述(由申请者提供)：本申请表为两机构合作探索/发展奖的初级研究员癫痫研究。皮特是肯塔基大学的助理教授，虽然在线粒体生物能量学和线粒体介导的细胞损伤和死亡领域发表了大量文章，但他在癫痫研究领域相对较新。在一次博士后研究期间，PI与加州大学欧文分校的一位知名癫痫研究人员发起了一项创新合作。这位合作者是生酮饮食(KD)抗惊厥作用机制方面的专家，这是一种治疗难治性癫痫的有效非药物疗法。KD是一种高脂肪、低碳水化合物/低蛋白质的饮食，旨在重现禁食后的早期生化变化。尽管KD已经有了几十年的成功临床经验，但其抗惊厥作用的机制仍然知之甚少。众所周知，禁食可增加外周血线粒体解偶联蛋白(UCP)的活性。然而，目前还没有数据说明KD对大脑线粒体解偶联的影响。在初步研究中，我们发现KD增强了正常小鼠大脑皮质线粒体的解偶联，并减少了ROS的产生。这项研究的基本目标是确定KD是否能减少癫痫发育期小鼠(即Kcnal缺失突变体)和正常小鼠急性兴奋性毒性损伤后海马区线粒体的氧化损伤。具体地说，我们假设KD增加了UCP介导的线粒体解偶联，并减少了癫痫海马区随后的ROS形成。此外，我们假设KD可减少红藻氨酸诱导的癫痫发作后线粒体功能障碍、脂质过氧化和蛋白质氧化。我们在红藻氨酸模型中的初步数据有力地表明了KD的直接神经保护作用，但与对照组饮食与KD处理的动物之间的癫痫发作严重程度无关。这些研究的结果将阐明KD是否在发育性癫痫的遗传模型中以及在公认的兴奋性毒性模型中减少氧化应激。这些发现的临床意义在于，这种疗法可以改善癫痫本身的状况，而不仅仅是阻止自发的反复发作活动。

DESCRIPTION (provided by applicant): This application is for a bi-institutional collaborative Exploratory/Developmental Award in Epilepsy Research for Junior Investigators. The PI is an Assistant Professor at the University of Kentucky, and although published extensively in the field of mitochondrial bioenergetics and mitochondria-mediated cellular injury and death, he is relatively new to the field of epilepsy research. During a post-doctoral fellowship, the PI initiated an innovative collaboration with an established epilepsy researcher at the University of California at Irvine. The co-PI is an expert on mechanisms underlying the anticonvulsant actions of the ketogenic diet (KD), an effective non-pharmacological treatment for medically refractory epilepsy. The KD is a high-fat, low-carbohydrate/low-protein diet designed to reproduce the early biochemical changes seen upon fasting. Despite decades of successful clinical experience with the KD, the mechanisms underlying its anticonvulsant actions remain poorly understood. It is well known that fasting increases peripheral mitochondrial uncoupling protein (UCP) activity. However, there are no data addressing the effects of a KD on brain mitochondrial uncoupling. In preliminary studies, we have found that a KD enhances mitochondrial uncoupling and decreases reactive oxygen species (ROS) production in normal mouse cortex. The fundamental goal of the proposed studies is to determine whether a KD decreases mitochondrial oxidative damage in the hippocampus of developing epileptic mice (i.e., the Kcnal-null mutant), and following acute excitotoxic insult in normal mice. Specifically, we hypothesize that a KD increases UCP-mediated mitochondrial uncoupling and reduces subsequent ROS formation in epileptic hippocampus. Additionally, we hypothesize that the KD reduces mitochondrial dysfunction, lipid peroxidation and protein oxidation following kainic acid-induced seizures. Our preliminary data in the kainic acid model strongly suggest a direct neuroprotective effect of the KD, not related to seizure severity between groups of control diet- vs. KD-treated animals. The results of these studies will shed light on whether a KD reduces oxidative stress in a genetic model of developmental epilepsy, as well as in a well-established excitotoxic model. The clinical importance of such findings is that this therapy may ameliorate the epileptic condition itself, and not merely halt spontaneous recurrent seizure activity.