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Gene expression profiles of beta-cell enriched tissue obtained by Laser Capture Microdissection from subjects with type 2 diabetes

ABSTRACT: Changes in gene expression in pancreatic beta-cells from type 2 diabetes could provide insights into their abnormal insulin secretion and beta-cell turnover. The laser capture microdissection technique was used to acquire beta-cells from pancreatic tissue sections obtained from type 2 diabetic (T2D) and non-diabetic controls. We found that 4% of analyzed transcripts were differentially expressed between the two groups at the lower confidence bound cutoff of 1.2, and, among the differentially expressed transcripts, 62% were up-regulated and 38% down-regulated in samples of T2D subjects compared to non-diabetic controls. We observed: 1) changes in expression of genes linked to glucotoxicity, in particular, up-regulation of LDHA and PCK1, and down-regulation of GPD2, ME1 and ACLY; 2) evidence of oxidative stress, documented by up-regulation of metallothionein genes; 3) few changes in the major genes associated with cell cycle, apoptosis or endoplasmic reticulum stress; 4) differential expression of genes associated with pancreatic regeneration, most notably up-regulation of members of the regenerating islet gene (REG) family and metalloproteinase 7; and 5) differential expression of some genes found in genome wide association studies to be related to T2D (IGF2BP2, TSPAN8, and HNF1B were up-regulated, while JAZF1 and SLC30A8 were down-regulated). In conclusion, this study has identified many novel changes in pancreatic beta-cell gene expression that enhance the understanding of the pathogenesis of T2D.

ORGANISM(S): Homo sapiens

PROVIDER: GSE20966 | GEO | 2010/03/20

SECONDARY ACCESSION(S): PRJNA124531

REPOSITORIES: GEO

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Gene expression profiles of beta-cell enriched tissue obtained by Laser Capture Microdissection from subjects with type 2 diabetes

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