Liver SVCT Systems: Vitamin C Uptake, Roles & Regulation

肝脏 SVCT 系统：维生素 C 摄取、作用

• 批准号: 7013031
• 负责人: JACK C REIDLING
• 金额: $ 12.31万
• 依托单位: UNIVERSITY OF CALIFORNIA-IRVINE
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-04-01 至 2011-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7013031
• 关键词: ascorbate; biological transport; cell line; gel mobility shift assay; genetic library; genetically modified animals; laboratory mouse; liver; liver cells; messenger RNA; protein isoforms; small interfering RNA; transcription factor; transport proteins; vitamin metabolism

DESCRIPTION (provided by applicant): This proposal has been designed to advance the Principle Investigator (PI) towards his goal of academic independence. To attain that objective he will learn advanced molecular biology and mouse genetic techniques as well as liver pathology/histology in his studies of vitamin C regulation in the liver. Ascorbic acid (vitamin C) is a required essential micronutrient and effective antioxidant in humans. Two isoforms of the sodium-dependent vitamin C transporters (SVCT1 and SVCT2) are expressed in many human and mouse tissues, including the liver. Nothing is known regarding the regulation or relative contribution of the SVCT systems toward the overall vitamin C uptake process in the liver. Understanding these mechanisms is clinically relevant since many liver related diseases benefit from optimizing vitamin C body homeostasis. Our studies will use both an in vitro and in vivo approach to perform a comprehensive examination of the human liver vitamin C uptake process and regulation. We will determine the characteristics/kinetics of vitamin C uptake, characterize the hSVCT1 and hSVCT2 promoters, establish the relative contribution of hSVCT1 and hSVCT2 toward total uptake using an siRNA approach and perform studies regarding the effects of adaptive regulation of the vitamin C uptake process, all in human liver cells. In addition we will determine the characteristics/kinetics of vitamin C uptake in the liver of an in vivo mouse model that like humans is unable to synthesize vitamin C, establish the relative contribution of mSVCT1 and mSVCT2 toward total uptake using the cre/lox system to generate liver specific knockouts of each gene independently, and continue our studies into adaptive regulation of vitamin C uptake in this in vivo model. Our studies into the mechanisms involved in maintaining and regulating normal vitamin C body homeostasis will potentially allow clinicians to develop effective strategies for patients during conditions of deficiency. The extensive training and educational opportunities will allow the PI to launch into a career as an independent academic researcher

描述（由申请人提供）： 该建议旨在将主要研究者（PI）推向其学术独立目标。为了实现这一目标，他将学习先进的分子生物学和小鼠遗传技术，以及肝脏病理学/组织学在他对肝脏中维生素C调节的研究中。抗坏血酸（维生素C）是人类必需的必需微量营养素和有效的抗氧化剂。依赖钠的维生素C转运蛋白的两种同工型（SVCT1和SVCT2）在包括肝脏在内的许多人和小鼠组织中表达。关于SVCT系统对肝脏整体维生素C摄取过程的调节或相对贡献，尚无任何了解。了解这些机制在临床上是相关的，因为许多肝脏相关疾病从优化维生素C身体稳态中受益。我们的研究将同时使用体外和体内方法对人肝脏维生素C摄取过程和调节进行全面检查。我们将确定维生素C摄取的特征/动力学，表征HSVCT1和HSVCT2启动子，建立HSVCT1和HSVCT2对使用siRNA方法对总摄取的相对贡献，并使用siRNA方法进行研究，并进行有关人类Liver细胞中维生素C摄取过程的适应性调节作用的研究。 In addition we will determine the characteristics/kinetics of vitamin C uptake in the liver of an in vivo mouse model that like humans is unable to synthesize vitamin C, establish the relative contribution of mSVCT1 and mSVCT2 toward total uptake using the cre/lox system to generate liver specific knockouts of each gene independently, and continue our studies into adaptive regulation of vitamin C uptake in this in vivo model.我们对维持和调节正常维生素C身体体内稳态涉及的机制的研究将有可能使临床医生在缺乏症状的情况下为患者制定有效的策略。广泛的培训和教育机会将使PI成为独立学术研究员的职业生涯