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- Gylvin, T., et al.
(author)
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Functional SOCS1 polymorphisms are associated with variation in obesity in whites
- 2009
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In: Diabetes, Obesity and Metabolism. - : Wiley. - 1462-8902 .- 1463-1326. ; 11:3, s. 196-203
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Journal article (peer-reviewed)abstract
- The suppressor of cytokine signalling 1 (SOCS1) is a natural inhibitor of cytokine and insulin signalling pathways and may also play a role in obesity. In addition, SOCS1 is considered a candidate gene in the pathogenesis of both type 1 diabetes (T1D) and type 2 diabetes (T2D). The objective was to perform mutation analysis of SOCS1 and to test the identified variations for association to T2D-related quantitative traits, T2D or T1D. Mutation scanning was performed by direct sequencing in 27 white Danish subjects. Genotyping was carried out by TaqMan allelic discrimination. A total of more than 8100 individuals were genotyped. Eight variations were identified in the 5' untranslated region (UTR) region. Two of these had allele frequencies below 1% and were not further examined. The six other variants were analysed in groups of T1D families (n = 1461 subjects) and T2D patients (n = 1430), glucose tolerant first-degree relatives of T2D patients (n = 212) and normal glucose tolerant (NGT) subjects. The rs33977706 polymorphism (-820G > T) was associated with a lower body mass index (BMI) (p = 0.004). In a second study (n = 4625 NGT subjects), significant associations of both the rs33977706 and the rs243330 (-1656G > A) variants to obesity were found (p = 0.047 and p = 0.015) respectively. The rs33977706 affected both binding of a nuclear protein to and the transcriptional activity of the SOCS1 promoter, indicating a relationship between this polymorphism and gene regulation. This study demonstrates that functional variations in the SOCS1 promoter may associate with alterations in BMI in the general white population.
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| 2. |
- Bergholdt, R, et al.
(author)
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Transcriptional profiling of type 1 diabetes genes on chromosome 21 in a rat beta-cell line and human pancreatic islets
- 2007
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In: Genes and Immunity. - : Springer Science and Business Media LLC. - 1476-5470 .- 1466-4879. ; 8:3, s. 232-238
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Journal article (peer-reviewed)abstract
- We recently finemapped a type 1 diabetes (T1D)-linked region on chromosome 21, indicating that one or more T1D-linked genes exist in this region with 33 annotated genes. In the current study, we have taken a novel approach using transcriptional profiling in predicting and prioritizing the most likely candidate genes influencing beta-cell function in this region. Two array-based approaches were used, a rat insulinoma cell line (INS-1 alpha beta) overexpressing pancreatic duodenum homeobox 1 (pdx-1) and treated with interleukin 1 beta (IL-1 beta) as well as human pancreatic islets stimulated with a mixture of cytokines. Several candidate genes with likely functional significance in T1D were identified. Genes showing differential expression in the two approaches were highly similar, supporting the role of these specific gene products in cytokine-induced beta-cell damage. These were genes involved in cytokine signaling, oxidative phosphorylation, defense responses and apoptosis. The analyses, furthermore, revealed several transcription factor binding sites shared by the differentially expressed genes and by genes demonstrating highly similar expression profiles with these genes. Comparable findings in the rat beta-cell line and human islets support the validity of the methods used and support this as a valuable approach for gene mapping and identification of genes with potential functional significance in T1D, within a region of linkage.
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| 3. |
- Yu, X., et al.
(author)
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Association of UCP2 - 866 G/A polymorphism with chronic inflammatory diseases
- 2009
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In: Genes and Immunity. - : Springer Science and Business Media LLC. - 1466-4879 .- 1476-5470. ; 10:6, s. 601-605
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Journal article (peer-reviewed)abstract
- We reported earlier that two mitochondrial gene polymorphisms, UCP2 -866 G/A (rs659366) and mtDNA nt13708 G/A (rs28359178), are associated with multiple sclerosis (MS). Here we aim to investigate whether these functional polymorphisms contribute to other eight chronic inflammatory diseases, including rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), Wegener' granulomatosis (WG), Churg-Strauss syndrome (CSS), Crohn's disease (CD), ulcerative colitis (UC), primary sclerosing cholangitis (PSC) and psoriasis. Compared with individual control panels, the UCP2 -866 G/A polymorphism was associated with RA and SLE, and the mtDNA nt13708 G/A polymorphism with RA. Compared with combined controls, the UCP2 -866 G/A polymorphism was associated with SLE, WG, CD and UC. When all eight disease panels and the original MS panel were combined in a meta-analysis, the UCP2 was associated with chronic inflammatory diseases in terms of either alleles (odds ratio (OR)=0.91, 95% confidence interval (95% CI): 0.86-0.96), P=0.0003) or genotypes (OR=0.88, (95% CI: 0.82-0.95), P=0.0008), with the -866A allele associated with a decreased risk to diseases. As the -866A allele increases gene expression, our findings suggest a protective role of the UCP2 protein in chronic inflammatory diseases.
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| 4. |
- Rønn, SG, et al.
(author)
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Suppressor of cytokine signalling-3 expression inhibits cytokine-mediated destruction of primary mouse and rat pancreatic islets and delays allograft rejection
- 2008
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In: Diabetologia. - : Springer Science and Business Media LLC. - 0012-186X .- 1432-0428. ; 51:10, s. 1873-1882
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Journal article (peer-reviewed)abstract
- Aims/hypothesis The pro-inflammatory cytokines IL-1 and IFN gamma are critical molecules in immune-mediated beta cell destruction leading to type 1 diabetes mellitus. Suppressor of cytokine signalling (SOCS)-3 inhibits the cytokine-mediated destruction of insulinoma-1 cells. Here we investigate the effect of SOCS3 in primary rodent beta cells and diabetic animal models. Methods Using mice with beta cell-specific Socs3 expression and a Socs3-encoding adenovirus construct, we characterised the protective effect of SOCS3 in mouse and rat islets subjected to cytokine stimulation. In transplantation studies of NOD mice and alloxan-treated mice the survival of Socs3 transgenic islets was investigated. Results Socs3 transgenic islets showed significant resistance to cytokine-induced apoptosis and impaired insulin release. Neither glucose-stimulated insulin release, insulin content or glucose oxidation were affected by SOCS3. Rat islet cultures transduced with Socs3-adenovirus displayed reduced cytokine-induced nitric oxide and apoptosis associated with inhibition of the IL-1-induced nuclear factor-kappa B and mitogen-activated protein kinase (MAPK) pathways. Transplanted Socs3 transgenic islets were not protected in diabetic NOD mice, but showed a prolonged graft survival when transplanted into diabetic allogenic BALB/c mice. Conclusions/interpretation SOCS3 inhibits IL-1-induced signalling through the nuclear factor-kappa B and MAPK pathways and apoptosis induced by cytokines in primary beta cells. Moreover, Socs3 transgenic islets are protected in an allogenic transplantation model. SOCS3 may represent a target for pharmacological or genetic engineering in islet transplantation for treatment of type 1 diabetes mellitus.
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