In vivo and in vitro studies of GAD-antibody positive subjects with Type 2 diabetes: A distinct sub-phenotype

The purpose of this study was to determine if immune mechanisms in GAD positive patients' contribute to the pathogenesis of a specific sub-type of Type 2 diabetes. GAD positive (n = 8) and GAD negative (n = 8) subjects diagnosed with Type 2 diabetes were matched for age, gender, body mass index...

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Main Authors: O'Gorman, D., Yousif, O., Dixon, G., McQuaid, S., Murphy, E., Rahman, Y., Gasparro, D., Pacini, G., Newsholme, Philip, Nolan, J.
Format: Journal Article
Published: Elsevier Ireland Ltd 2008
Online Access:http://hdl.handle.net/20.500.11937/19890
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author O'Gorman, D.
Yousif, O.
Dixon, G.
McQuaid, S.
Murphy, E.
Rahman, Y.
Gasparro, D.
Pacini, G.
Newsholme, Philip
Nolan, J.
author_facet O'Gorman, D.
Yousif, O.
Dixon, G.
McQuaid, S.
Murphy, E.
Rahman, Y.
Gasparro, D.
Pacini, G.
Newsholme, Philip
Nolan, J.
author_sort O'Gorman, D.
building Curtin Institutional Repository
collection Online Access
description The purpose of this study was to determine if immune mechanisms in GAD positive patients' contribute to the pathogenesis of a specific sub-type of Type 2 diabetes. GAD positive (n = 8) and GAD negative (n = 8) subjects diagnosed with Type 2 diabetes were matched for age, gender, body mass index, duration of diabetes and glycaemic control. All subjects underwent an insulin-modified frequently sampled intravenous glucose tolerance test to measure insulin sensitivity and insulin secretory function with minimal model analysis. In addition, BRIN-BD11 clonal ß-cells were supplemented with patients' sera to determine basal and alanine-stimulated insulin secretion and terminal complement complex (TCC) formation. Both groups were severely insulin resistant (0.56 ± 0.17 vs. 0.99 ± 0.33 10-4 min-1/(µU ml-1) for GADneg and GADpos, respectively) but the GAD negative subjects had a higher basal (87 ± 11 vs. 58 ± 14 pmol l-1, p < 0.05) and glucose-stimulated insulin secretion (?AUCins 0.96 ± 0.12 vs. 0.60 ± 0.12 pmol/(l-1 min), p < 0.05). In vivo measures of insulin secretion were negatively correlated with TCC formation, independent of antibody status. In conclusion, GAD positive subjects initially diagnosed with Type 2 diabetes are unable to compensate for insulin resistance due to more pronounced ß-cell impairment. TCC formation may be partly responsible for the insulin secretory dysfunction associated with this specific sub-type of Type 2 diabetes. © 2007 Elsevier Ireland Ltd. All rights reserved.
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publishDate 2008
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spelling curtin-20.500.11937-198902017-09-13T13:50:23Z In vivo and in vitro studies of GAD-antibody positive subjects with Type 2 diabetes: A distinct sub-phenotype O'Gorman, D. Yousif, O. Dixon, G. McQuaid, S. Murphy, E. Rahman, Y. Gasparro, D. Pacini, G. Newsholme, Philip Nolan, J. The purpose of this study was to determine if immune mechanisms in GAD positive patients' contribute to the pathogenesis of a specific sub-type of Type 2 diabetes. GAD positive (n = 8) and GAD negative (n = 8) subjects diagnosed with Type 2 diabetes were matched for age, gender, body mass index, duration of diabetes and glycaemic control. All subjects underwent an insulin-modified frequently sampled intravenous glucose tolerance test to measure insulin sensitivity and insulin secretory function with minimal model analysis. In addition, BRIN-BD11 clonal ß-cells were supplemented with patients' sera to determine basal and alanine-stimulated insulin secretion and terminal complement complex (TCC) formation. Both groups were severely insulin resistant (0.56 ± 0.17 vs. 0.99 ± 0.33 10-4 min-1/(µU ml-1) for GADneg and GADpos, respectively) but the GAD negative subjects had a higher basal (87 ± 11 vs. 58 ± 14 pmol l-1, p < 0.05) and glucose-stimulated insulin secretion (?AUCins 0.96 ± 0.12 vs. 0.60 ± 0.12 pmol/(l-1 min), p < 0.05). In vivo measures of insulin secretion were negatively correlated with TCC formation, independent of antibody status. In conclusion, GAD positive subjects initially diagnosed with Type 2 diabetes are unable to compensate for insulin resistance due to more pronounced ß-cell impairment. TCC formation may be partly responsible for the insulin secretory dysfunction associated with this specific sub-type of Type 2 diabetes. © 2007 Elsevier Ireland Ltd. All rights reserved. 2008 Journal Article http://hdl.handle.net/20.500.11937/19890 10.1016/j.diabres.2007.12.009 Elsevier Ireland Ltd restricted
spellingShingle O'Gorman, D.
Yousif, O.
Dixon, G.
McQuaid, S.
Murphy, E.
Rahman, Y.
Gasparro, D.
Pacini, G.
Newsholme, Philip
Nolan, J.
In vivo and in vitro studies of GAD-antibody positive subjects with Type 2 diabetes: A distinct sub-phenotype
title In vivo and in vitro studies of GAD-antibody positive subjects with Type 2 diabetes: A distinct sub-phenotype
title_full In vivo and in vitro studies of GAD-antibody positive subjects with Type 2 diabetes: A distinct sub-phenotype
title_fullStr In vivo and in vitro studies of GAD-antibody positive subjects with Type 2 diabetes: A distinct sub-phenotype
title_full_unstemmed In vivo and in vitro studies of GAD-antibody positive subjects with Type 2 diabetes: A distinct sub-phenotype
title_short In vivo and in vitro studies of GAD-antibody positive subjects with Type 2 diabetes: A distinct sub-phenotype
title_sort in vivo and in vitro studies of gad-antibody positive subjects with type 2 diabetes: a distinct sub-phenotype
url http://hdl.handle.net/20.500.11937/19890