RESVERATROL BIOAVAILABILITY--PRECLINICAL AND CLINICAL

描述：（申请人描述）流行病学研究，以及 对实验室动物的研究表明，存在于水果中的多酚， 蔬菜和饮料，对多种癌症有保护作用。 一 越来越多的生物化学研究表明， 这些影响的机制。 然而，目前尚不清楚在多大程度上和 其形成膳食多酚在人体肠道中被吸收， 因此可以获得对所提议的蜂窝活动站点的访问。 临床和 多酚生物利用度的动物研究一般已经 不成功，我们正在使用一种中间临床前方法，使用 Caco-2细胞系作为人肠吸收模型以及 新陈代谢. 这项研究的重点是多酚白藜芦醇， 葡萄和红酒中的植物抗毒素。 我们的假设是Caco-2 细胞模型高度预测的吸收和代谢， 人体内的白藜芦醇 在目标1中，我们将首先确定吸收，即顶端到 白藜芦醇通过Caco-2细胞单层的基底外侧转运，使用 分子特异性HPLC测定。 这也将产生代谢的命运， 白藜芦醇，包括潜在的氧化以及共轭产物， 通过HPLC/MS和其他光谱方法鉴定。 剂量依赖性 运输和新陈代谢将是特别关注的问题。 相应的离体吸收研究，即基底外侧至顶端转运， 为了确定可能的定向运输， 白藜芦醇及其代谢产物介导的外排泵，如 P-糖蛋白和MRPs。 此外，我们将确定药物 参与白藜芦醇生物转化的代谢酶。 在目标2中， 将直接决定白藜芦醇的口服生物利用度。 这 需要口服（25毫克）和静脉注射（1毫克 mg）剂量。 将给予50 microCi的（14 C）标记的白藜芦醇 以使其能够确定回收率和完整的 白藜芦醇的代谢命运。 这也将有助于评估 粪便排泄是多酚类物质排泄的主要途径。 从这些 数据，我们将确定药代动力学参数 白藜芦醇，包括清除率（总清除率、肾清除率、代谢清除率、粪便清除率）， 消除半衰期和分布容积。 目标1和目标2将使我们确定Caco-2细胞的有用性 作为临床前模型。

DESCRIPTION: (Applicant's Description) Epidemiological studies, as well as studies in laboratory animals, suggest that polyphenols, present in fruits, vegetables and beverages, have protective effects in a variety of cancers. A rapidly growing number of biochemical studies show a vast array of plausible mechanisms for these effects. However, it is not clear to what extent and in which form the dietary polyphenols are absorbed in the human intestine and thus can gain access to proposed cellular sites of action. As clinical and animal studies of the bioavailability of the polyphenols in general have been unsuccessful, we are using an intermediary preclinical approach, using the Caco-2 cell line as model of human intestinal absorption as well as metabolism. The proposed study is focusing on the polyphenol resveratrol, a phytoalexin in grapes and red wine. Our working hypothesis is that the Caco-2 cell model is highly predictive of both absorption and metabolism of resveratrol in humans in vivo. In Aim 1 we will in first hand determine the absorption, i.e. apical to basolateral transport across the Caco-2 cell monolayer, of resveratrol, using a molecularly specific HPLC assay. This will also yield the metabolic fate of resveratrol, including potential oxidation as well as conjugation products, identified by HPLC/MS and other spectroscopic methods. Dose-dependency in transport and metabolism will be of particular concern. Corresponding studies of ex sorption, i.e. basolateral to apical transport, will be done in order to determine the possible directional transport of resveratrol and its metabolites mediated by efflux pumps, such as P-glycoprotein and the MRPs. In addition, we will identify the drug metabolizing enzymes involved in resveratrol biotransformation. In Aim 2 we will in first hand determine the oral bioavailability of resveratrol. This will require the administration of both an oral (25 mg) and an intravenous (1 mg) dose. Fifty microCi of (14C)-labeled resveratrol will be administered with each dose to make it possible to determine recoveries and the complete metabolic fate of resveratrol. This will also make it possible to assess fecal elimination, the major route of elimination of polyphenols. From these data we will determine the pharmacokinetic parameters for resveratrol, including clearances (total, renal, metabolic, fecal), elimination half -life and volume of distribution. Together Aims 1 and 2 will let us determine the usefulness of the Caco-2 cells as a preclinical model.