Pilot Test of a Novel Behavioral Intervention on BP Control in HTN Patients

维生素E是一种有效的脂溶抗氧化剂，它的作用机制是 繁殖，是未知的[1]。维生素E的抗氧化剂和生物活性之间存在着二分法， 因为植物合成了八种不同的具有维生素E抗氧化活性的分子，但只有一种 这些是-生育酚，是动物所需的营养物质。我们认为，没有成功地确定 -生育酚的分子功能有两个主要障碍。首先，-生育酚需要 给药到组织的特殊运输机制，并参与复杂的相互作用 各种氧化和抗氧化系统；这些因素在很大程度上决定了细胞培养研究的结果 误导性的。其次，使用实验动物获取组织(尤其是胚胎)是困难的 充分消耗生育酚，可用于鉴定生育酚敏感功能。免去 针对这些问题，我们建议使用维生素E耗竭的斑马鱼(Danio Rerio)作为模型系统。 斑马鱼是脊椎动物，其基因通常与人类的基因同源， 可以饲养动物，可以很容易地操纵饮食，可以很容易地修改目标基因，以及 胚胎阶段可以在发育过程中进行研究。关键是，-生育酚转移 蛋白(-ttp)在人卵黄囊中表达[2]，在受精后48小时大量表达。 (HPF)斑马鱼胚胎及其表达随着氧化压力的增加而增加[3]。因此，- 三磷酸腺苷可能参与-生育酚从卵黄囊向胚胎的转移。 为了研究生育酚缺乏(E-)斑马鱼，我们开发了一种明确的生育酚缺乏的饲料 并在初步研究中证明，E-斑马鱼具有生育能力，并能够产生可存活的胚胎。 到48HPF时，许多E-胚胎表现出严重的发育畸形。缺陷包括 颅面和心血管异常，从而将-生育酚需求与神经学联系起来 和心血管疾病的发展。 根据我们的文献回顾，我们假设-生育酚对 胚胎发育所必需的特定的、关键的脂质介质，包括通过程序化的细胞损失 细胞死亡。具体地说，谷胱甘肽过氧化物酶4(Gpx4)，磷脂氢过氧化物的解毒剂， 感受氧化应激并将其转化为由12/15-脂氧合酶介导的细胞死亡(12/15 LOX)和凋亡诱导因子(AIF)[4]。重要的是，-生育酚，但不是水溶性的 抗氧化剂，有效地防止细胞死亡。这些发现支持-生育酚是 在胚胎发育过程中是必需的，以调节特定发育步骤中涉及的脂质介体， 尤其是在神经系统中。为了验证这一假设，我们提出了以下目标： 目的1.明确-生育酚转移蛋白(-TTP)在胚胎发育中的作用 假设：-ttp存在于胚胎的卵黄囊中，并且呈递增表达。 在胚胎发育期间，促进-生育酚转移到关键部位。-生育酚是必需的 对于胚胎发育的最早细胞，允许适当的脂质介体调节。 目的2.明确氧化和抗氧化细胞凋亡调节因子在胚胎发育过程中的作用 发展 假设：-生育酚是必要的，以防止关键介质的异常脂质过氧化。12/15- LOX增加脂质过氧化，从而发出AIF转位和细胞死亡的信号。相反的12/15-LOX 是Gpx4，它使用谷胱甘肽(作为辅助因子)，并解毒磷脂过氧化氢。因此， Gpx4抑制脂质过氧化作用。-生育酚不仅可以阻止脂质过氧化连锁反应，它还可以 是繁殖所必需的。因此，-生育酚将阻止，它的存在将 如果GSH合成或Gpx4表达被取消，则会加剧发育异常。如果 12/15-LOX或AIF表达下调，-生育酚的影响较小。 目的3.确定-生育酚在神经系统发育中的作用 假设：神经系统对-生育酚缺乏特别敏感；因此，缺乏 发育中胚胎中的-生育酚会导致特定的神经系统畸形和 功能障碍。 斑马鱼模型是我们研究的理想模型，因为它和人类一样，对-生育酚有偏好， 表达ttp基因并需要维生素C，维生素C是中的重要决定因素-生育酚抗氧化剂 在人类身上的功能[5]。此外，-生育酚缺陷斑马鱼胚胎表现出 异常提示神经和心血管发育障碍。我们的长期目标 是定义因生育酚缺乏而改变的分子靶点，因为这种机制数据可以 在其他模型系统中进行测试，最终将这些结果转化为我们对原因的基本理解 人类需要-生育酚，不仅是为了生殖，也是为了维持健康的神经系统。 斑马鱼使我们能够区分-生育酚缺乏对胚胎本身的影响，单独 孕妇孕期生育酚缺乏症。考虑到这一点，我们的方法是让我们的 生物系统对侮辱(生育酚缺乏)做出反应，然后追求潜在的 通过利用斑马鱼模型的优势来实现这一机制。使用这种方法，我们的斑马鱼 研究将使我们能够记录特定的-生育酚分子功能，关键的抗氧化剂/氧化剂 信号机制，以及确定在哪些阶段需要-生育酚

The mechanisms of action of vitamin E, a potent lipid soluble antioxidant that is necessary for reproduction, are unknown [1]. A dichotomy exists between vitamin E’s antioxidant and biologic activities, in that plants synthesize eight different molecules with vitamin E antioxidant activity, yet only one of these, -tocopherol, is a nutrient required by animals. We believe that the lack of success in determining the molecular function of -tocopherol results from two major obstacles. First, -tocopherol requires special transport mechanisms for delivery to tissues and is involved in complex interactions between various oxidizing and antioxidant systems; these factors make outcomes from cell culture studies largely misleading. Secondly, it is difficult using experimental animals to obtain tissues (especially embryos) that are sufficiently -tocopherol-depleted to be useful to identify -tocopherol-sensitive functions. To obviate these problems, we propose to use vitamin E-depleted zebrafish (Danio rerio) as a model system. Zebrafish are vertebrate animals with genes generally homologous to those of humans, large numbers of animals can be raised, diets can easily be manipulated, targeted genes can be readily modified, and embryonic stages can be studied over the course of development. Critically, the -tocopherol transfer protein (-TTP) is expressed in human yolk sac [2], is abundantly expressed by the 48 hour postfertilization (hpf) zebrafish embryo and its expression increases with oxidative stress [3]. Therefore, - TTP likely mediates -tocopherol transfer to the embryo from the yolk sac. To study -tocopherol-deficient (E-) zebrafish, we have developed a defined, -tocopherol-deficient diet and demonstrate in preliminary studies that E-zebrafish are fertile and capable of producing viable, Eembryos. By 48 hpf, many E- embryos exhibit severe developmental malformations. Defects include craniofacial and cardiovascular abnormalities, thereby linking -tocopherol requirements to neurological and cardiovascular development. Based on our literature review, we hypothesize that -tocopherol provides antioxidant protection for specific, key lipid mediators necessary for embryonic development, including cell loss via programmed cell death. Specifically, glutathione peroxidase 4 (GPx4), a detoxifier of phospholipid hydroperoxides, senses and translates oxidative stress into cell death that is mediated by both 12/15-lipoxygenase (12/15 LOX) and apoptosis-inducing factor (AIF) [4]. Importantly, -tocopherol, but not water-soluble antioxidants, efficiently prevented cell death. These findings support the hypothesis that -tocopherol is necessary during embryogenesis to modulate lipid mediators involved in specific developmental steps, especially in the nervous system. To test this hypothesis, we propose the following aims: Aim 1. Define the role of the -tocopherol transfer protein (-TTP) during embryonic development Hypothesis: -TTP is present in the yolk sac of the embryo, and is expressed in increasing amounts during embryonic development, to facilitate -tocopherol transfer to key sites. -Tocopherol is necessary for the earliest cells in embryonic development to allow appropriate lipid-mediator regulation. Aim 2. Define the roles of oxidant and antioxidant apoptosis regulators during embryonic development Hypothesis: -tocopherol is necessary to prevent abnormal lipid peroxidation of key mediators. 12/15- LOX increases lipid peroxidation thereby signaling AIF translocation and cell death. Opposing 12/15-LOX is GPX4, which uses glutathione (as a co-factor) and detoxifies phospholipid hydroperoxides. Thus, GPX4 suppresses lipid peroxidation. -Tocopherol not only stops the lipid peroxidation chain reaction, it is absolutely required for reproduction. Therefore, -tocopherol will prevent, and its absence will potentiate, developmental abnormalities if either GSH synthesis or GPX4 expression is abrogated. If 12/15-LOX or AIF expression is knocked down, -tocopherol will have a lesser effect. Aim 3. Define the role of -tocopherol in the developing nervous system Hypothesis: The nervous system is especially sensitive to -tocopherol deficiency; therefore, the lack of -tocopherol in the developing embryo will result in specific nervous system malformation and dysfunction. The zebrafish model is ideal for our studies because it, like humans, has a preference for -tocopherol, expresses the ttp gene and requires vitamin C, an important determinant in -tocopherol antioxidant function in humans [5]. Moreover, the -tocopherol deficient zebrafish embryo displays characteristic abnormalities suggesting dysfunctional neurological and cardiovascular development. Our long-term goal is to define molecular targets altered by -tocopherol-deficiency because this mechanistic data can then be tested in other model systems, ultimately translating these results to our basic understanding of why humans require -tocopherol, not just for reproduction, but also to maintain a healthy nervous system. The zebrafish allows us to distinguish the effect of -tocopherol deficiency in the embryo itself, separate from maternal -tocopherol deficiency during gestation. With that in mind, our approach is to let our biological system respond to the insult (-tocopherol-deficiency), and then pursue the underlying mechanism by exploiting the advantages of the zebrafish model. Using this approach, our zebrafish studies will allow us to document specific -tocopherol molecular functions, key antioxidant/oxidant signaling mechanisms, as well as determining at what stages -tocopherol is required