| Literature DB >> 28082409 |
Andrew H Huber1, Alan M Kleinfeld2.
Abstract
We determined for the first time the profiles of the nine most abundant unbound FFAs (FFAus) in human plasma. Profiles were determined for a standard reference plasma of pooled healthy adults for which the Lipid MAPSMAPS Consortium had determined the total FFA profiles. Measurements were performed by using 20 different acrylodan-labeled fatty acid binding protein mutants (probes), which have complementary specificities for the nine FFAs that comprise more than 96% of long-chain plasma FFA. The acrylodan fluorescence emission for each probe changes upon binding a FFAu. The plasma concentrations of each of the nine FFAus were determined by combining the measured fluorescence ratios of the 20 probes. The total molar FFAu concentration accounted for <10-5 of the total FFA concentration, and the mole fractions of the FFAu profiles were substantially different than the total FFA profiles. Myristic acid, for example, comprises 22% of the unbound versus 2.8% of the total. The most surprising difference is our finding of zero unbound cis-9-palmitoleic acid (POA), whereas the total POA was 7.2%. An unidentified plasma component appears to specifically prevent the release of POA. FFAus are the physiologically active FFAs, and plasma FFAu profiles may provide novel information about human health.Entities:
Keywords: albumin binding; fatty acid binding proteins; fluorescence; lipidomics; metabolism; physical biochemistry; quantitation
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Year: 2017 PMID： 28082409 PMCID： PMC5335587 DOI： 10.1194/jlr.M074260
Source DB: PubMed Journal: J Lipid Res ISSN： 0022-2275 Impact factor: 5.922