Qualitative Distribution of Endogenous Cholesteryl Esters in Plasma of Humans and Three Rodent Species Using Stepwise UPLC-Q-Exactive-MS

Abstract

Objective

Cholesteryl esters (CEs) are composed of various fatty acyl chains attached to the hydroxyl groups of cholesterol, and abnormalities in their metabolism are related to many diseases. This study aimed to develop an ultrahigh-performance liquid chromatography-quadrupole exactive mass spectrometry (UPLC-Q-Exactive MS) method to identify the CEs in plasma.

Methods

First, the MS fragmentation patterns were investigated using seven commercial CE standards. Then, the CEs in plasma were characterized through the accurate mass data of precursor ions and characteristic product ions. A strategy of step-by-step m/z scans in a narrow range was proposed to identify more trace CEs by the full-scan data-dependent MS/MS (ddMS2) mode.

Results

A total of 50 CE species consisting of 55 regioisomers were identified in human plasma. Among them, two species were reported for the first time.

Conclusion

This study is the most comprehensive identification of CE species in human plasma to date. These results will contribute to the in-depth profiling of CEs in human plasma and provide guidance for animal model selection when studying lipid-related diseases.

Keywords

cholesteryl ester / ultrahigh-performance liquid chromatography-quadrupole exactive mass spectrometry / profile / plasma

References

[1] LuoJ, YangH, SongBL. Mechanisms and regulation of cholesterol homeostasis. Nat Rev Mol Cell Biol, 2020, 21(4): 225-245

[2] YangW, BaiY, XiongY, et al.. Potentiating the antitumour response of CD8(+) T cells by modulating cholesterol metabolism. Nature, 2016, 531(7596): 651-655

[3] ShibuyaY, ChangCCY, ChangTY. ACAT1/SOAT1 as a therapeutic target for Alzheimer’s disease. Future Med Chem, 2015, 7(18): 2451-2467

[4] Garcia-BermudezJ, BirsoyK. Drugging ACAT1 for Cancer Therapy. Mol Cell, 2016, 64(5): 856-857

[5] QuehenbergerO, ArmandoAM, BrownAH, et al.. Lipidomics reveals a remarkable diversity of lipids in human plasma. J Lipid Res, 2010, 51(11): 3299-3305

[6] TalbotCPJ, PlatJ, JorisPJ, et al.. HDL cholesterol efflux capacity and cholesteryl ester transfer are associated with body mass, but are not changed by diet-induced weight loss: A randomized trial in abdominally obese men. Atheroscler, 2018, 274(1): 23-28

[7] GerlMJ, VazWLC, DominguesN, et al.. Cholesterol is Inefficiently Converted to Cholesteryl Esters in the Blood of Cardiovascular Disease Patients. Sci Rep, 2018, 8(1): 14764

[8] SekiyaM, OsugaJI, NagashimaS, et al.. Ablation of Neutral Cholesterol Ester Hydrolase 1 Accelerates Atherosclerosis. Cell Metab, 2009, 10(3): 219-228

[9] ProitsiP, KimM, WhileyL, et al.. Plasma lipidomics analysis finds long chain cholesteryl esters to be associated with Alzheimer’s disease. Transl Psychiatry, 2015, 5(1): e494

[10] MayengbamSS, SinghA, PillaiAD, et al.. Influence of cholesterol on cancer progression and therapy. Transl Oncol, 2021, 14(6): 101043

[11] PradaM, WittenbecherC, EichelmannF, et al.. Association of the odd-chain fatty acid content in lipid groups with type 2 diabetes risk: A targeted analysis of lipidomics data in the EPIC-Potsdam cohort. Clin Nutr, 2021, 40(8): 4988-4999

[12] ZhouJ, ChenX, ChenW, et al.. Comprehensive plasma metabolomic and lipidomic analyses reveal potential biomarkers for heart failure. Mol Cell Biochem, 2021, 476(9): 3449-3460

[13] LiuT, PengF, YuJ, et al.. LC-MS-based lipid profile in colorectal cancer patients: TAGs are the main disturbed lipid markers of colorectal cancer progression. Anal Bioanal Chem, 2019, 411(20): 5079-5088

[14] TarasovK, EkroosK, SuoniemiM, et al.. Molecular lipids identify cardiovascular risk and are efficiently lowered by simvastatin and PCSK9 deficiency. J Clin Endocrinol Metab, 2014, 99(1): E45-52

[15] AfshinniaF, RajendiranTM, KarnovskyA, et al.. Lipidomic Signature of Progression of Chronic Kidney Disease in the Chronic Renal Insufficiency Cohort. Kidney Int Rep, 2016, 1(4): 256-268

[16] ChanRB, OliveiraTG, CortesEP, et al.. Comparative Lipidomic Analysis of Mouse and Human Brain with Alzheimer Disease. J Biol Chem, 2012, 287(4): 2678-2688

[17] MichalecC, SulcM, MestanJ. Analysis of cholesteryl esters and triglycerides by thin-layer chromatography. Nature, 1962, 193(4810): 63-64

[18] SubramanianA, JoshiBS, RoyAD, et al.. NMR spectroscopic identification of cholesterol esters, plasmalogen and phenolic glycolipids as fingerprint markers of human intracranial tuberculomas. NMR Biomed, 2008, 21(3): 272-288

[19] AsmisR, BuhlerE, JelkJ, et al.. Concurrent quantification of cellular cholesterol, cholesteryl esters and triglycerides in small biological samples — Reevaluation of thin layer chromatography using laser densitometry. J Chromatogr B, 1997, 691(1): 59-66

[20] HammannS, VetterW. Gas chromatographic separation of fatty acid esters of cholesterol and phytosterols on an ionic liquid capillary column. J Chromatogr B, 2015, 1007(1): 67-71

[21] LiebischG, BinderM, SchiffererR, et al.. High throughput quantification of cholesterol and cholesteryl ester by electrospray ionization tandem mass spectrometry (ESI-MS/MS). Biochim Biophys Acta Mol Cell Biol Lipids, 2006, 1761(1): 121-128

[22] LinM, WangZ, WangD, et al.. Mathematical Model-Assisted UHPLC-MS/MS Method for Global Profiling and Quantification of Cholesteryl Esters in Hyperlipidemic Golden Hamsters. Anal Chem, 2019, 91(7): 4504-4512

[23] TrieblA, TroetzmuellerM, HartlerJ, et al.. Lipidomics by ultrahigh performance liquid chromatography-high resolution mass spectrometry and its application to complex biological samples. J Chromatogr B, 2017, 1053(1): 72-80

[24] SalaP, PoetzS, BrunnerM, et al.. Determination of Oxidized Phosphatidylcholines by Hydrophilic Interaction Liquid Chromatography Coupled to Fourier Transform Mass Spectrometry. Int J Mol Sci, 2015, 16(4): 8351-8363

[25] ContrepoisK, MahmoudiS, UbhiBK, et al.. Cross-Platform Comparison of Untargeted and Targeted Lipidomics Approaches on Aging Mouse Plasma. Sci Rep, 2018, 8(1): 17747

[26] CajkaT, SmilowitzJT, FiehnO. Validating Quantitative Untargeted Lipidomics Across Nine Liquid Chromatography-High-Resolution Mass Spectrometry Platforms. Anal Chem, 2017, 89(22): 12360-12368

[27] KoelmelJP, KroegerNM, GillEL, et al.. Expanding Lipidome Coverage Using LC-MS/MS Data-Dependent Acquisition with Automated Exclusion List Generation. J Am Soc Mass Spectrom, 2017, 28(5): 908-917

[28] ZhouJ, LiY, ChenX, et al.. Development of data-independent acquisition workflows for metabolomic analysis on a quadrupole-orbitrap platform. Talanta, 2017, 164(1): 128-136

[29] MatyashV, LiebischG, KurzchaliaTV, et al.. Lipid extraction by methyl-tert-butyl ether for high-throughput lipidomics. J Lipid Res, 2008, 49(5): 1137-1146

[30] HasanM, SiegmundW, OswaldS. Rapid LC-MS/MS method for the determination of 4-hydroxycholesterol/cholesterol ratio in serum as endogenous biomarker for CYP3A activity in human and foals. J Chromatogr B, 2016, 1033(1): 193-199

[31] YuS, DongJ, ZhouW, et al.. A rapid and precise method for quantification of fatty acids in human serum cholesteryl esters by liquid chromatography and tandem mass spectrometry. J Chromatogr B, 2014, 960(1): 222-229

[32] CajkaT, FiehnO. Comprehensive analysis of lipids in biological systems by liquid chromatography-mass spectrometry. Trends Anal Chem, 2014, 61(1): 192-206

[33] GardnerMS, McWilliamsLG, JonesJI, et al.. Simultaneous Quantification of Free Cholesterol, Cholesteryl Esters, and Triglycerides without Ester Hydrolysis by UHPLC Separation and In-Source Collision Induced Dissociation Coupled MS/MS. J Am Soc Mass Spectrom, 2017, 28(11): 2319-2329

[34] YanZ, YanR. Improved Data-Dependent Acquisition for Untargeted Metabolomics Using Gas-Phase Fractionation with Staggered Mass Range. Anal Chem, 2015, 87(5): 2861-2868

[35] FenailleF, Barbier Saint-HilaireP, RousseauK, et al.. Data acquisition workflows in liquid chromatography coupled to high resolution mass spectrometry-based metabolomics: Where do we stand?. J Chromatogr A, 2017, 1526(1): 1-12

[36] HuB, SongC, LiL, et al.. Qualitative distribution of endogenous phosphatidylcholine and sphingomyelin in serum using LC-MS/MS based profiling. J Chromatogr B, 2020, 1155(1): 122289

[37] LiuX, WangJ, HuB, et al.. Qualitative distribution of endogenous sphingolipids in plasma of human and rodent species by UPLC-Q-Exactive-MS. J Chromatogr B, 2021, 1173(1): 122684