| Autor: |
Liliane Schoofs, Daniel Aaen Hansen, Decio L. Eizirik, Daisy Flamez, Ettienne Waelkens, Gert Van den Bergh, Gabriela B Ferreira, Michael Maris, Yves Moreau, Alessandra K Cardozo, Lut Overbergh, Wannes D'Hertog, Lut Arckens, Chantal Mathieu, Conny Gysemans, Kasper Lage |
| Rok vydání: |
2007 |
| Předmět: |
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| Zdroj: |
Molecular & Cellular Proteomics. 6:2180-2199 |
| ISSN: |
1535-9476 |
| DOI: |
10.1074/mcp.m700085-mcp200 |
| Popis: |
Cytokines released by islet-infiltrating immune cells play a crucial role in beta-cell dysfunction and apoptotic cell death in the pathogenesis of type 1 diabetes and after islet transplantation. RNA studies revealed complex pathways of genes being activated or suppressed during this beta-cell attack. The aim of the present study was to analyze protein changes in insulin-producing INS-1E cells exposed to inflammatory cytokines in vitro using two-dimensional DIGE. Within two different pH ranges we observed 2214 +/- 164 (pH 4-7) and 1641 +/- 73 (pH 6-9) spots. Analysis at three different time points (1, 4, and 24 h of cytokine exposure) revealed that the major changes were taking place only after 24 h. At this time point 158 proteins were altered in expression (4.1%, n = 4, p < or = 0.01) by a combination of interleukin-1beta and interferon-gamma, whereas only 42 and 23 proteins were altered by either of the cytokines alone, giving rise to 199 distinct differentially expressed spots. Identification of 141 of these by MALDI-TOF/TOF revealed proteins playing a role in insulin secretion, cytoskeleton organization, and protein and RNA metabolism as well as proteins associated with endoplasmic reticulum and oxidative stress/defense. We investigated the interactions of these proteins and discovered a significant interaction network (p < 1.27e-05) containing 42 of the identified proteins. This network analysis suggests that proteins of different pathways act coordinately in a beta-cell dysfunction/apoptotic beta-cell death interactome. In addition the data suggest a central role for chaperones and proteins playing a role in RNA metabolism. As many of these identified proteins are regulated at the protein level or undergo post-translational modifications, a proteomics approach, as performed in this study, is required to provide adequate insight into the mechanisms leading to beta-cell dysfunction and apoptosis. The present findings may open new avenues for the understanding and prevention of beta-cell loss in type 1 diabetes. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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