title: Human Plasma N-glycosylation as Analyzed by Matrix-Assisted Laser Desorption/Ionization-Fourier Transform Ion Cyclotron Resonance-MS Associates with Markers of Inflammation and Metabolic Health.
abstract: Glycosylation is an abundant co- and post-translational protein modification of importance to protein processing and activity. Although not template-defined, glycosylation does reflect the biological state of an organism and is a high-potential biomarker for disease and patient stratification. However, to interpret a complex but informative sample like the total plasma N-glycome, it is important to establish its baseline association with plasma protein levels and systemic processes. Thus far, large-scale studies (n >200) of the total plasma N-glycome have been performed with methods of chromatographic and electrophoretic separation, which, although being informative, are limited in resolving the structural complexity of plasma N-glycans. MS has the opportunity to contribute additional information on, among others, antennarity, sialylation, and the identity of high-mannose type species.Here, we have used matrix-assisted laser desorption/ionization (MALDI)-Fourier transform ion cyclotron resonance (FTICR)-MS to study the total plasma N-glycome of 2144 healthy middle-aged individuals from the Leiden Longevity Study, to allow association analysis with markers of metabolic health and inflammation. To achieve this, N-glycans were enzymatically released from their protein backbones, labeled at the reducing end with 2-aminobenzoic acid, and following purification analyzed by negative ion mode intermediate pressure MALDI-FTICR-MS. In doing so, we achieved the relative quantification of 61 glycan compositions, ranging from Hex4HexNAc2to Hex7HexNAc6dHex1Neu5Ac4, as well as that of 39 glycosylation traits derived thereof. Next to confirming known associations of glycosylation with age and sex by MALDI-FTICR-MS, we report novel associations with C-reactive protein (CRP), interleukin 6 (IL-6), body mass index (BMI), leptin, adiponectin, HDL cholesterol, triglycerides (TG), insulin, gamma-glutamyl transferase (GGT), alanine aminotransferase (ALT), and smoking. Overall, the bisection, galactosylation, and sialylation of diantennary species, the sialylation of tetraantennary species, and the size of high-mannose species proved to be important plasma characteristics associated with inflammation and metabolic health.
authors.affiliation: From the ‡Center for Proteomics and Metabolomics, Leiden University Medical Center, 2300 RC Leiden, The Netherlands.
authors.forename: Karli R
authors.initials: KR
authors.lastname: Reiding
authors.affiliation: §Department of Clinical Chemistry and Laboratory Medicine, Leiden University Medical Center, 2300 RC Leiden, The Netherlands.
authors.forename: L Renee
authors.initials: LR
authors.lastname: Ruhaak
authors.affiliation: ¶Department of Medical Statistics and Bioinformatics, Leiden University Medical Center, 2300 RC Leiden, The Netherlands.
authors.forename: Hae-Won
authors.initials: HW
authors.lastname: Uh
authors.affiliation: ¶Department of Medical Statistics and Bioinformatics, Leiden University Medical Center, 2300 RC Leiden, The Netherlands.
authors.forename: Said
authors.initials: S
authors.lastname: El Bouhaddani
authors.affiliation: ¶Department of Medical Statistics and Bioinformatics, Leiden University Medical Center, 2300 RC Leiden, The Netherlands.|**Pattern Recognition & Bioinformatics, Delft University of Technology, 2600 GA Delft, The Netherlands.
authors.forename: Erik B
authors.initials: EB
authors.lastname: van den Akker
authors.affiliation: From the ‡Center for Proteomics and Metabolomics, Leiden University Medical Center, 2300 RC Leiden, The Netherlands.
authors.forename: Rosina
authors.initials: R
authors.lastname: Plomp
authors.affiliation: From the ‡Center for Proteomics and Metabolomics, Leiden University Medical Center, 2300 RC Leiden, The Netherlands.
authors.forename: Liam A
authors.initials: LA
authors.lastname: McDonnell
authors.affiliation: ¶Department of Medical Statistics and Bioinformatics, Leiden University Medical Center, 2300 RC Leiden, The Netherlands.|‡‡Department of Statistics, University of Leeds, LS2 9JT Leeds, United Kingdom.
authors.forename: Jeanine J
authors.initials: JJ
authors.lastname: Houwing-Duistermaat
authors.affiliation: ‖Department of Molecular Epidemiology, Leiden University Medical Center, 2300 RC Leiden, The Netherlands.
authors.forename: P Eline
authors.initials: PE
authors.lastname: Slagboom
authors.affiliation: ‖Department of Molecular Epidemiology, Leiden University Medical Center, 2300 RC Leiden, The Netherlands.
authors.forename: Marian
authors.initials: M
authors.lastname: Beekman
authors.affiliation: From the ‡Center for Proteomics and Metabolomics, Leiden University Medical Center, 2300 RC Leiden, The Netherlands; m.wuhrer@lumc.nl.
authors.forename: Manfred
authors.initials: M
authors.lastname: Wuhrer
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000097:blood*; D015992:Body Mass Index; D002097:C-Reactive Protein / Q000378:metabolism; D017357:Cyclotrons; D005583:Fourier Analysis; D006031:Glycosylation; D006801:Humans; D007249:Inflammation / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D040901:Proteomics / Q000295:instrumentation*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000295:instrumentation*
chemical_list: D015415:Biomarkers; D002097:C-Reactive Protein