Molecular flux rates through critical pathways measured by stable isotope labeling in vivo, as biomarkers of drug action and disease activity

摘要

The methods described herein enable the evaluation of compounds on subjects to assess their therapeutic efficacy or toxic effects. The target of analysis is the underlying biochemical process or processes (i.e., metabolic process) thought to be involved in disease pathogenesis. Molecular flux rates within the one or more biochemical processes serve as biomarkers and are quantitated and compared with the molecular flux rates (i.e., biomarker) from control subjects (i.e., subjects not exposed to the compounds). Any change in the biomarker in the subject relative to the biomarker in the control subject provides information to evaluate therapeutic efficacy of an administered drug or a toxic effect and to develop the compound further if desired. In one aspect of the invention, stable isotope-labeled substrate molecules are administered to a subject and the label is incorporated into targeted molecules in a manner that reveals molecular flux rates through metabolic pathways of interest.

主权项

1. A method for evaluating an action of one or more compounds on a molecular flux rate through a hepatic de novo lipogenesis pathway in a living system, said method comprising:
a) administering a first isotope-labeled substrate to a first living system, not exposed to said one or more compounds, for a period of time sufficient for said first isotope-labeled substrate to enter into and label at least one fatty acid to produce at least one first isotope-labeled fatty acid within said hepatic de novo lipogenesis pathway in said first living system; b) obtaining one or more samples from said first living system, wherein said one or more samples comprise said at least one first isotope-labeled fatty acid; c) measuring an isotopic content, rate of incorporation, and/or pattern or rate of change in isotopic content and/or pattern of isotope labeling of said at least one first isotope-labeled fatty acid; d) calculating a molecular flux rate through said hepatic de novo lipogenesis pathway based on the isotopic content, rate of incorporation, and/or pattern or rate of change of isotopic content and/or pattern of isotopic labeling in said at least one first isotope-labeled fatty acid; e) exposing a second living system to said one or more compounds; f) administering a second isotope-labeled substrate to said second living system for a period of time sufficient for said second isotope-labeled substrate to enter into and label at least one fatty acid to produce at least one second isotope-labeled fatty acid; g) obtaining one or more samples from said second living system, wherein said one or more samples comprise said at least one second isotope-labeled fatty acid; h) measuring an isotopic content, rate of incorporation, and/or pattern or rate of change in isotopic content and/or pattern of isotope labeling of said at least one second isotope-labeled fatty acid; i) calculating a molecular flux rate through said hepatic de novo lipogenesis pathway in said second living system based on the isotopic content, rate of incorporation, and/or pattern or rate of change in isotopic content and/or pattern of isotope labeling of said at least one second isotope-labeled fatty acid; and j) comparing said molecular flux rate through said hepatic de novo lipogenesis pathway in said first living system to said molecular flux rate through said hepatic de novo lipogenesis pathway in said second living system to evaluate the action of said one or more compounds on said molecular flux rate through the hepatic de novo lipogenesis pathway in said second living system.