Novel, Noninvasive Biomarker of Fruit & Vegetable Intake

水果/蔬菜和慢性疾病的流行病学研究受到缺乏饮食摄入/饮食依从性干预的非侵入性客观生物标志物的限制。类胡萝卜素的血液浓度被认为是水果和蔬菜摄入量的最佳生物标志物，但需要静脉穿刺，而且对于大型队列研究和干预试验来说成本过高。类胡萝卜素存在于包括皮肤在内的许多人体组织中，并且类胡萝卜素的皮肤浓度（来自真皮活检）已被证明是强烈的， 与相同类胡萝卜素的血浆浓度显著相关（例如，β-胡萝卜素，r=0.75）。我们建议调整现有的技术，拉曼光谱，在体内作为水果和蔬菜摄入量的生物标志物的人体组织的类胡萝卜素状态的评估。更具体地说，我们建议（i）完善我们目前的仪器，如有一个坚固的，便携式装置，用于快速评估类胡萝卜素状态在人体皮肤在体内。 一旦我们的原型仪器得到适当的改进，我们建议（ii）评估重现性， 受试者内变化和受试者间皮肤类胡萝卜素水平的变化，如通过拉曼光谱在同一时间和随时间估计的。完成这一目标后，我们的最终目标是（iii）确定类胡萝卜素状态之间的相关性，如通过拉曼光谱和类胡萝卜素状态的其他措施，包括水果/蔬菜和特定的类胡萝卜素，血浆类胡萝卜素浓度和类胡萝卜素浓度在皮肤活检评估。目前正在开发/完善这项有前途的技术，以评估 这项研究的主要目的是研究人类视网膜组织中的类胡萝卜素（国家眼科研究所）;目前的提议将大大拓宽这种非侵入性技术在癌症流行病学和预防研究中的潜在用途。拉曼光谱技术具有巨大的潜力，作为一种突破性的方法，快速筛选类胡萝卜素的水平在大的人口，发展和验证是迫切需要将这项技术转移到人口的研究和监测。

Epidemiologic studies of fruits/vegetables and chronic disease have been limited by the lack of non-invasive objective biomarkers of dietary intake/dietary adherence to interventions. Blood concentrations of carotenoids are considered the best biological markers of fruit and vegetable intake, but require venipuncture and are prohibitively expensive for large cohort studies and intervention trials. Carotenoids are found in many human tissues including skin, and skin concentrations of carotenoids (from dermal biopsies) have been shown to be strongly and significantly correlated with plasma concentrations of the same carotenoids (e.g., beta-carotene, r=0.75). We propose to adapt an existing technology, Raman spectroscopy, for the assessment of the carotenoid status of human tissues in vivo as a biomarker of fruit and vegetable intake. More specifically, we propose to (i) refine our current instrument such as to have a rugged, portable device for rapidly assessing carotenoid status ill human skin in vivo. Once our protype instrument is appropriately refined, we then propose to (ii) evaluate the reproducibility, intra-subject variability, and inter-subject variability in dermal cartenoid levels as estimated by Raman spectroscopy at one time and over time. Upon completion of this aim, our final aim is to (iii) determine the correlation between carotenoid status as assessed by Raman spectroscopy and other measures of carotenoid status including dietary intake of fruits/vegetables and specific carotenoids, plasma carotenoid concentrations and carotenioid concentrations in dermal biopsies. This promising technology is currently being developed/refined for the assessment of carotenoids in human retinal tissue (National Eye Institute); the current proposal would greatly broaden the potential use of this noninvasive technology for cancer epidemiology and prevention studies. Raman spectroscopic technology has tremendous potential as a breakthrough method for rapid screening of carotenoid levels in large populations, and development and validation are critically required to move this technology into human population research and surveillance.