DIETARY CAROTENOIDS--TRANSPORT IN HUMAN PLASMA

膳食类胡萝卜素——在人体血浆中的运输

• 批准号: 2225914
• 负责人: EARL Howard HARRISON
• 金额: $ 18.86万
• 依托单位: ALLEGHENY UNIVERSITY OF HEALTH SCIENCES
• 依托单位国家: 美国
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-07-01 至 1997-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2225914
• 关键词: antioxidants; biological transport; blood chemistry; blood lipoprotein; blood lipoprotein metabolism; carotene; carotenoids; cholesterol; diet; dietary constituent; dietary supplements; high performance liquid chromatography; human subject; nutrient bioavailability; nutrient interaction; nutrition related tag; oxidation; oxidized lipid; plasma; steroid metabolism; tissue /cell culture; tocopherols

Carotenoids are tetraterpene pigments whose de novo biosynthesis is restricted to plants and microorgamsms. Thus, humans obtain carotenoids in the diet by the ingestion of fruits and vegetables. Historically, it was thought that the most important role of some carotenoids in the human diet was their metabolic conversion to the essential micronutrient, vitamin A (retinol), and indeed, consumption of carotenoid-containing foods fulfills a significant part of the vitamin A requirement of many humans. More recently, other important roles for dietary carotenoids which are independent of their conversion to vitamin A have been suggested. In particular, recent studies suggest that carotenoids can inhibit both carcinogenesis and lipoprotein oxidation due to their intrinsic properties as fat soluble antioxidants. Thus carotenoids may help prevent both cancer and atherosclerotic heart disease. In spite of these potentially important roles in human health, little detailed information is available on the transport of carotenoids in human plasma. The objective of the present proposal is to define the transport systems for carotenoids in human plasma and the role of these compounds in preventing or retarding lipoprotein oxidation. Under AIM 1 we will determine the distribution of individual carotenoids among human plasma lipoproteins. This will be done by isolating lipoproteins, extracting carotenoids and quantitating them by high performance liquid chromatography. We will test the hypothesis that the lipid-soluble carotenoids will be associated with the plasma lipoproteins. Under AIM 2, we will explore the role of individual carotenoids in protecting plasma lipoproteins from oxidation. Isolated lipoproteins will be oxidized in vitro and the kinetics of disappearance of endogenous carotenoids and the appearance of oxidized lipids will be assessed by chemical analyses. The biological consequences of lipoprotein oxidation will be assessed using functional assays. We will test the hypothesis that oxidation of lipoproteins does not occur until endogenous carotenoids are destroyed. Under AIM 3 we will enrich the lipoproteins in individual carotenoids by oral ingestion of carotenoids and see if this leads to increased resistance of the lipoproteins to oxidative damage. We will test the hypothesis that increased consumption of carotenoids protects lipoproteins from oxidation.

类胡萝卜素是一种四萜色素，其从头生物合成是 仅限于植物和微生物。因此，人类在体内获得类胡萝卜素 通过摄入水果和蔬菜来节食。从历史上看，它是 认为某些类胡萝卜素在人类饮食中最重要的作用 他们的代谢转化为必需的微量营养素--维生素A (视黄醇)，事实上，摄入含胡萝卜素的食物就满足了 这是许多人所需的维生素A的重要组成部分。更多 最近，饮食中类胡萝卜素的其他重要作用是 已经提出了独立于它们转化为维生素A的研究。在……里面 特别是，最近的研究表明，类胡萝卜素可以抑制这两种作用 脂蛋白因其固有性质而致癌和氧化 作为脂溶抗氧化剂。因此，类胡萝卜素可能有助于预防这两种癌症 和动脉粥样硬化性心脏病。尽管有这些潜在重要因素 在人类健康中的作用，几乎没有详细的信息 类胡萝卜素在人血浆中的转运。当前的目标是 建议定义类胡萝卜素在人体内的运输系统 血浆和这些化合物在预防或延缓中的作用 脂蛋白氧化。在目标1下，我们将确定 人血浆脂蛋白中的个别类胡萝卜素。这件事会做到的 通过分离脂蛋白，提取类胡萝卜素，并通过 高效液相色谱仪。我们将检验这一假设 脂溶类胡萝卜素将与血浆有关 脂蛋白。在目标2下，我们将探讨个人的作用 类胡萝卜素保护血浆脂蛋白免受氧化。孤立 脂蛋白在体外会被氧化和消失的动力学 内源性类胡萝卜素和氧化脂质的出现 通过化学分析进行评估。脂蛋白的生物学后果 氧化将使用功能分析进行评估。我们将测试 脂蛋白氧化直到内源性才发生的假说 类胡萝卜素就会被破坏。在目标3下，我们将在 通过口服类胡萝卜素来单独摄入类胡萝卜素，看看这是否 导致脂蛋白对氧化损伤的抵抗力增强。我们 将检验增加类胡萝卜素摄入量的假设 保护脂蛋白免受氧化。