Podium Presentation in Room 2 on Thursday at 11:40 (Chair: Richard Drake)
Authors: Elham Memarian(1,2)Emma Schoep(3)Roosmarijn Lemmers(4)Marco Bladergroen(1)Jan Nouta(1)Gerda Vreeker(1)Aloysius Lieverse(5)Femke Rutters(6)Amber van der Heijden(7)Petra Elders(7)Joline WJ Beulens(6)Roderick Slieker(3,6)Eric Sijbrands(4)Leen `t Hart(3,6,8)Manfred Wuhrer(1)Mandy van Hoek(4)Viktoria Dotz(1)
Type 2 diabetes mellitus (T2D) represents a major public health challenge. The total plasma N-glycome (TPNG) reflects the levels and glycosylation of major plasma glycoproteins, among which are immunoglobulins, acute-phase proteins and apolipoproteins. Although associations of TPNG with T2D have been recently reported by us and others, data on the association between TPNG and T2D complications are scarce. Here, we applied our new ultrahigh-resolution MS method to assess associations of TPNG with T2D complications.
We determined the TPNG in a subsample of the Hoorn Diabetes Care System cohort (n = 1519 T2D cases and 192 nondiabetic controls from the New Hoorn study cohort) using our Fourier-transform ion cyclotron resonance MS method. Blood plasma samples were randomized over 21 96-well plates, together with technical replicates. Prior to MS analysis, N-glycans were released using PNGase F. For stabilization and linkage differentiation, sialic acids were derivatized. Released glycans were purified and spotted using an automated liquid handling platform. In total, 68 individual glycan compositions were quantified after total-area normalization and summarized into derived traits representing structural features. By applying logistic regression models, we tested for associations of TPNG with case-control status and micro- or macrovascular complications, such as nephropathy, retinopathy, or cardiovascular disease (cross-sectional). T2D complications were also assessed prospectively by Cox regression. Models were adjusted for age, sex, and T2D risk factors. The outputs were meta-analyzed together with our MALDI-TOF-MS data from the independent cohort DiaGene (1815 T2D cases and 836 controls) which we obtained and described previously.
The recently developed method using MALDI-FTICR-MS improved resolution, mass accuracy, dynamic range and the signal-to-noise ratio, especially for larger glycans, in comparison to our previous MALDI-TOF workflow. The relative standard deviation over the 68 detected glycan species was on average 6.6%, based on the relative intensities from 93 technical replicates of pooled plasma, representing total method repeatability.
We found significant associations of all major glycosylation traits, i.e. sialylation, fucosylation, galactosylation, bisection, and glycan complexity with T2D in the meta-analyses of both cross-sectional and prospective data. For example, the bisection and galactosylation of immunoglobulin-related glycans were associated with macrovascular complications and nephropathy. We aim to confirm these results in the near future on protein-specific level, by isolating IgG prior to released-glycan analysis.
Our new method improved the detection of several glycan species, thus providing possible new insights into the association between TPNG and T2D. Our results will be taken forward to improve personalized approaches in T2D and related complications in the future.
|Grants||yes||Glysign project funding from the European Union’s Horizon 2020|
|Salary||yes||Genos d.o.o company based on Glysign project funding from the European Union’s Horizon 2020|
|Expenses||yes||Genos d.o.o company based on Glysign project funding from the European Union’s Horizon 2020|
|Planning to mention or discuss specific products or technology of the company(ies) listed above:||