title: Applications of stable, nonradioactive isotope tracers in in vivo human metabolic research.
abstract: The human body is in a constant state of turnover, that is, being synthesized, broken down and/or converted to different compounds. The dynamic nature of in vivo kinetics of human metabolism at rest and in stressed conditions such as exercise and pathophysiological conditions such as diabetes and cancer can be quantitatively assessed with stable, nonradioactive isotope tracers in conjunction with gas or liquid chromatography mass spectrometry and modeling. Although measurements of metabolite concentrations have been useful as general indicators of one's health status, critical information on in vivo kinetics of metabolites such as rates of production, appearance or disappearance of metabolites are not provided. Over the past decades, stable, nonradioactive isotope tracers have been used to provide information on dynamics of specific metabolites. Stable isotope tracers can be used in conjunction with molecular and cellular biology tools, thereby providing an in-depth dynamic assessment of metabolic changes, as well as simultaneous investigation of the molecular basis for the observed kinetic responses. In this review, we will introduce basic principles of stable isotope methodology for tracing in vivo kinetics of human or animal metabolism with examples of quantifying certain aspects of in vivo kinetics of carbohydrate, lipid and protein metabolism.
authors.affiliation: Department of Geriatrics, the Center for Translational Research on Aging and Longevity, Donald W. Reynolds Institute on Aging, College of Medicine, The University of Arkansas for Medical Sciences, Little Rock, AR, USA.
authors.forename: Il-Young
authors.initials: IY
authors.lastname: Kim
authors.affiliation: Deparatment of Physical Education, College of Sciences in Education, Yonsei University, Seoul, Republic of Korea.
authors.forename: Sang-Hoon
authors.initials: SH
authors.lastname: Suh
authors.affiliation: Section of Endocrinology, Department of Internal Medicine, School of Medicine, Kyungpook National University, Daegu, Republic of Korea.
authors.forename: In-Kyu
authors.initials: IK
authors.lastname: Lee
authors.affiliation: Department of Geriatrics, the Center for Translational Research on Aging and Longevity, Donald W. Reynolds Institute on Aging, College of Medicine, The University of Arkansas for Medical Sciences, Little Rock, AR, USA.
authors.forename: Robert R
authors.initials: RR
authors.lastname: Wolfe
mesh_terms: D004734:Energy Metabolism; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D007554:Isotopes / Q000008:administration & dosage / Q000378:metabolism; D055432:Metabolomics / Q000379:methods*; D008962:Models, Theoretical
chemical_list: D007554:Isotopes