Aim: A traditional oral fatty acid challenge assesses absorption of triacylglycerol (TG) into the periphery through the intestines, but cannot distinguish the composition or source of fatty acid in the TG. Stable isotope-labeled tracers combined with LC-MRM can be used to identify and distinguish TG synthesized with dietary and stored fatty acids. Results: Concentrations of three abundant TGs (52:2, 54:3 and 54:4) were monitored for incorporation of one or two ²H₁₁-oleate molecules per TG. This method was subjected to routine assay validation and meets typical requirements for an assay to be used to support clinical studies. Conclusion: Calculations for the fractional appearance rate of TG in plasma are presented along with the intracellular enterocyte precursor pool for 12 study participants.

Keywords:

Papers of special note have been highlighted as: • of interest; •• of considerable interest

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Vol. 8, No. 12

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Published online 26 May 2016

Published in print June 2016

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Financial & competing interests disclosure

X Li, DG McLaren, DL Chappell, T McAvoy, G Salituro, OF Laterza and ME Lassman are current employees of Merck & Co and hold stock in Merck & Co. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.

Ethical conduct of research

The authors state that they have obtained appropriate institutional review board approval or have followed the principles outlined in the Declaration of Helsinki for all human or animal experimental investigations. In addition, for investigations involving human subjects, informed consent has been obtained from the participants involved.

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