ASSESSING HIGH DIETARY VITAMIN A

这个子项目是利用由NIH/NCRR资助的中心拨款提供的资源的许多研究子项目之一。子项目和调查员(PI)可能从另一个NIH来源获得了主要资金，因此可能会出现在其他CRISE条目中。列出的机构是针对中心的，而不一定是针对调查员的机构。为了进一步确定长期高维生素A饮食的影响，最近研究了被用作人类生物医学研究模型的恒河猴(Macaca Mulatta)的维生素A(VA)状况，发现肝脏VA浓度处于亚毒性。绒猴(Callithrix Jacchus)也表现出高VA水平和高血清视黄酯浓度。这两个物种都食用共同的研究饮食，提供的VA量是国家研究委员会推荐的四倍。对这些发现的进一步解释仅限于组织视黄醇和视黄酯的分布和其他物种的外推，而不是直接与正常值进行比较。为了进一步确定恒河猴的VA状态，使用雄性恒河猴进行了一项涉及稳定同位素和肝脏活检的研究。虽然VA分析仍在进行中，但我们在16只雄性恒河猴(年龄从8到15岁)中的10只发现了化学筛查资料中的异常值。在猴子中，这些包括升高的碱性磷酸酶、γ-谷氨酰转移酶、乳酸脱氢酶和天冬氨酸转氨酶。这些酶的升高是值得关注的，因为它们都是肝脏疾病或功能障碍的标志，这是维生素A中毒的直接结果。这项研究使用了WNPRC Research Services。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. To further define the effects of chronically high dietary vitamin A. Recent work examining the vitamin A (VA) status of rhesus monkeys (Macaca mulatta) used as models for human biomedical research revealed subtoxic hepatic VA concentrations. Marmoset monkeys (Callithrix jacchus), also showed high VA levels and high serum retinyl ester concentration. Both species consumed common research diets that provided up to four times the amount of VA recommended by the National Research Council. Further interpretation of these findings is limited to tissue retinol and retinyl ester profiles and extrapolation from other species rather than direct comparison to normal values. To further define VA status in rhesus monkeys, male rhesus monkeys were used for a study that involved stable isotopes and liver biopsies. While the VA analysis is still in process, we found ¿abnormal¿ values in the chemistry screening profiles in 10 of the 16 male rhesus monkeys (age range 8 to 15 years). Among the monkeys, these included elevated alkaline phosphatase, gamma-glutamyl transferase, lactate dehydrogenase, and aspartate aminotransferase. Elevations of these enzymes are cause for concern as they are all markers of liver disease or malfunction, which is a direct outcome of vitamin A toxicity. This research used WNPRC Research Services.