title: Effect of Error Propagation in Stable Isotope Tracer Studies: An Approach for Estimating Impact on Apparent Biochemical Flux.
abstract: Stable isotope tracers are widely used to quantify metabolic rates, and yet a limited number of studies have considered the impact of analytical error on estimates of flux. For example, when estimating the contribution of de novo lipogenesis, one typically measures a minimum of four isotope ratios, i.e., the precursor and product labeling pre- and posttracer administration. This seemingly simple problem has 1 correct solution and 80 erroneous outcomes. In this report, we outline a methodology for evaluating the effect of error propagation on apparent physiological endpoints. We demonstrate examples of how to evaluate the influence of analytical error in case studies concerning lipid and protein synthesis; we have focused on (2)H2O as a tracer and contrast different mass spectrometry platforms including GC-quadrupole-MS, GC-pyrolysis-IRMS, LC-quadrupole-MS, and high-resolution FT-ICR-MS. The method outlined herein can be used to determine how to minimize variations in the apparent biology by altering the dose and/or the type of tracer. Likewise, one can facilitate biological studies by estimating the reduction in the noise of an outcome that is expected for a given increase in the number of replicate injections.
authors.affiliation: Merck Research Laboratories, Kenilworth, New Jersey, USA. Electronic address: stephen_previs@merck.com.
authors.forename: Stephen F
authors.initials: SF
authors.lastname: Previs
authors.affiliation: Merck Research Laboratories, Kenilworth, New Jersey, USA.
authors.forename: Kithsiri
authors.initials: K
authors.lastname: Herath
authors.affiliation: Merck Research Laboratories, Kenilworth, New Jersey, USA.
authors.forename: Jose
authors.initials: J
authors.lastname: Castro-Perez
authors.affiliation: Merck Research Laboratories, Kenilworth, New Jersey, USA.
authors.forename: Ablatt
authors.initials: A
authors.lastname: Mahsut
authors.affiliation: Merck Research Laboratories, Kenilworth, New Jersey, USA.
authors.forename: Haihong
authors.initials: H
authors.lastname: Zhou
authors.affiliation: Merck Research Laboratories, Kenilworth, New Jersey, USA.
authors.forename: David G
authors.initials: DG
authors.lastname: McLaren
authors.affiliation: Merck Research Laboratories, Kenilworth, New Jersey, USA.
authors.forename: Vinit
authors.initials: V
authors.lastname: Shah
authors.affiliation: Merck Research Laboratories, Kenilworth, New Jersey, USA.
authors.forename: Rory J
authors.initials: RJ
authors.lastname: Rohm
authors.affiliation: Merck Research Laboratories, Kenilworth, New Jersey, USA.
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Stout
authors.affiliation: Merck Research Laboratories, Kenilworth, New Jersey, USA.
authors.forename: Wendy
authors.initials: W
authors.lastname: Zhong
authors.affiliation: Merck Research Laboratories, Kenilworth, New Jersey, USA.
authors.forename: Sheng-Ping
authors.initials: SP
authors.lastname: Wang
authors.affiliation: Merck Research Laboratories, Kenilworth, New Jersey, USA.
authors.forename: Douglas G
authors.initials: DG
authors.lastname: Johns
authors.affiliation: Merck Research Laboratories, Kenilworth, New Jersey, USA.
authors.forename: Brian K
authors.initials: BK
authors.lastname: Hubbard
authors.affiliation: Merck Research Laboratories, Kenilworth, New Jersey, USA.
authors.forename: Michele A
authors.initials: MA
authors.lastname: Cleary
authors.affiliation: Merck Research Laboratories, Kenilworth, New Jersey, USA.
authors.forename: Thomas P
authors.initials: TP
authors.lastname: Roddy
mesh_terms: D000818:Animals; D002247:Carbon Isotopes; D002849:Chromatography, Gas / Q000379:methods; D002853:Chromatography, Liquid / Q000379:methods; D017666:Deuterium Oxide; D006801:Humans; D007553:Isotope Labeling / Q000379:methods*; D013058:Mass Spectrometry / Q000379:methods*; D008660:Metabolism; D059629:Signal-To-Noise Ratio
chemical_list: D002247:Carbon Isotopes; D017666:Deuterium Oxide
keywords: Cardiovascular disease; Diabetes; Dyslipidemia; Isotope ratio mass spectrometry; Lipogenesis; Mass isotopomer distribution analysis; Protein synthesis