Separation and quantification of 2-acyl-1-lysophospholipids and 1-acyl-2-lysophospholipids in biological samples by LC-MS/MS

Abstract

This article is available online at http://www.jlr.org by specific receptors belonging to the class A G proteincoupled receptor (GPCR) family ( 1 ). To date, 16 such GPCRs have been identified, including 6 lysophosphatidic acid (LPA) receptors, 5 sphingosine 1-phosphate receptors, 4 lysophosphatidylserine (LysoPS) receptors, and 1 lysophosphatidylinositol (LPI) receptor ( 1-4 ). Recent studies of gene-targeting mice have clearly shown that these receptors function individually in various pathological and physiological conditions ( 5 ).Glycero-LysoGPs have one acyl chain that is linked to either the sn -1 or sn -2 position of glycerol. Phospholipase A (PLA) 1 and PLA 2 cleave diacyl-phospholipids (GPs) and produce 2-acyl-1-lysophospholipids (2-acyl-1-LysoGPs) and 1-acyl-2-LysoGPs, respectively. Recent studies have suggested that some LysoGP receptors discriminate 1-acyl-2-LysoGPs from 2-acyl-1-LysoGPs. For example, LPA 3 / Edg7 ( 6, 7 ) and LPA 6 /P2Y5 ( 8 ) prefer 2-acyl-1-LPA to 1-acyl-2-LPA. In addition, they prefer LPA with unsaturated fatty acids, which are usually attached at the sn -2 position of GPs. LPS 1 /GPR34 also shows preference for 2-acyl-1-LysoPS ( 9 ). These fi ndings indicate that 2-acyl-1-LysoGPs exert their activities through specific receptors. Because of their different activities, 2-acyl-1-LysoGPs and 1-acyl-2-LysoGPs should be quantifi ed separately.However, it has been diffi cult to detect and quantify 2-acyl-1-LysoGPs in biological samples because 2-acyl-1-LysoGPs

Possible Involvement of Minor Lysophospholipids in the Increase in Plasma Lysophosphatidic Acid in Acute Coronary Syndrome

“…To overcome this limitation, we determined the LPA species using liquid chromatography-tandem mass spectrometry (LC-MS/ MS), as described previously. [22][23][24] Using this method, we were able to measure 12 acyl-chain LPA species, including 22:6 LPA, which has not been reported in any previous clinical studies, to our knowledge. Moreover, we were also able to determine other minor lysophospholipids (LPLs) (lysophosphatidylethanolamine [LPE], lysophosphatidylglycerol [LPG], lysophosphatidylinositol [LPI], and lysophosphatidylserine), the plasma concentrations of which had not been investigated in ACS subjects.…”

Autotaxin–lysophosphatidic acid– LPA 3 signaling at the embryo‐epithelial boundary controls decidualization pathways

“…While we could not detect LPA in the eggs, small amount of LPA (0.1–0.2 nM) was found in the uterine flushing fluids from the pregnant mice (Appendix Fig S3). Interestingly, LPA with an unsaturated fatty acid (oleic or linoleic acid), a potent ligand for LPA 3 (Bandoh et al , 2000), was detected when the uteri were flushed with the saline containing albumin which is capable of extracting lysophospholipids from outer leaflet of the cells (Okudaira et al , 2014; Appendix Fig S3). LPA was hardly recovered in the albumin‐free flushing fluids (Appendix Fig S3), indicating clearly that LPA is present in the extracellular milieu.…”

“…(10 or 30 mg/kg), and then, bloods were collected. Collected samples were processed for LC‐MS/MS as previously performed (Okudaira et al , 2014). …”

Substrate Selectivity of Lysophospholipid Transporter LplT Involved in Membrane Phospholipid Remodeling in Escherichia coli

“…Harvat et al (13) using 2-acyl-lyso-PE generated by the Rhizopus arrhizus lipase determined a K d value for this E. coli homolog 5ϫ lower than our result determined with the LplT-Kp protein and 1-acyl isomer. It may be difficult to determine the stereoselectivity of LplT because compelling evidence from different groups has shown that 2-acyl-lysophospholipids are extremely unstable in biological solution and are quickly converted to the 1-acyl-2-lyso form by a spontaneous intramolecular acyl migration, yielding a mixture mainly containing 1-acyl-2-lysoglycerophospholipids (15,34). We cannot rule out utilization of both lysolipid isomers by Lplt/Aas on the bacterial membrane.…”