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Pancreatic α Cells are Resistant to Metabolic Stress-induced Apoptosis in Type 2 Diabetes.

ABSTRACT: Pancreatic α cells are exposed to metabolic stress during the evolution of type 2 diabetes (T2D), but it remains unclear whether this affects their survival. We used electron microscopy to search for markers of apoptosis and endoplasmic reticulum (ER) stress in α and β cells in islets from T2D or non-diabetic individuals. There was a significant increase in apoptotic β cells (from 0.4% in control to 6.0% in T2D), but no α cell apoptosis. We observed, however, similar ER stress in α and β cells from T2D patients. Human islets or fluorescence-activated cell sorting (FACS)-purified rat β and α cells exposed in vitro to the saturated free fatty acid palmitate showed a similar response as the T2D islets, i.e. both cell types showed signs of ER stress but only β cells progressed to apoptosis. Mechanistic experiments indicate that this α cell resistance to palmitate-induced apoptosis is explained, at least in part, by abundant expression of the anti-apoptotic protein Bcl2l1 (also known as Bcl-xL).

SUBMITTER: Marroqui L

PROVIDER: S-EPMC4485913 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature

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Pancreatic α Cells are Resistant to Metabolic Stress-induced Apoptosis in Type 2 Diabetes.

Marroqui Laura L Masini Matilde M Merino Beatriz B Grieco Fabio A FA Millard Isabelle I Dubois Christine C Quesada Ivan I Marchetti Piero P Cnop Miriam M Eizirik Decio L DL

EBioMedicine 20150317 5

Pancreatic α cells are exposed to metabolic stress during the evolution of type 2 diabetes (T2D), but it remains unclear whether this affects their survival. We used electron microscopy to search for markers of apoptosis and endoplasmic reticulum (ER) stress in α and β cells in islets from T2D or non-diabetic individuals. There was a significant increase in apoptotic β cells (from 0.4% in control to 6.0% in T2D), but no α cell apoptosis. We observed, however, similar ER stress in α and β cells f ...[more]

PMID: 26137583

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Dataset Information

Pancreatic α Cells are Resistant to Metabolic Stress-induced Apoptosis in Type 2 Diabetes.

Publications

Pancreatic α Cells are Resistant to Metabolic Stress-induced Apoptosis in Type 2 Diabetes.

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