Document Detail


cJUN N-terminal kinase (JNK) activation mediates islet amyloid-induced beta cell apoptosis in cultured human islet amyloid polypeptide transgenic mouse islets.
MedLine Citation:
PMID:  22038516     Owner:  NLM     Status:  Publisher    
Abstract/OtherAbstract:
AIMS/HYPOTHESIS: Aggregation of human islet amyloid polypeptide (hIAPP) as islet amyloid is associated with increased beta cell apoptosis and reduced beta cell mass in type 2 diabetes. Islet amyloid formation induces oxidative stress, which contributes to beta cell apoptosis. The cJUN N-terminal kinase (JNK) pathway is a critical mediator of beta cell apoptosis in response to stress stimuli including oxidative stress and exogenous application of hIAPP. We determined whether amyloid formation by endogenous hIAPP mediates beta cell apoptosis through JNK activation and downstream signalling pathways. METHODS: hIAPP transgenic and non-transgenic mouse islets were cultured for up to 144 h in 16.7 mmol/l glucose to induce islet amyloid in the presence or absence of the amyloid inhibitor Congo Red or a cell-permeable JNK inhibitor. Amyloid, beta cell apoptosis, JNK signalling and activation of downstream targets in the intrinsic and extrinsic apoptotic pathways were measured. RESULTS: JNK activation occurred with islet amyloid formation in hIAPP transgenic islets after 48 and 144 h in culture. Neither high glucose nor the hIAPP transgene alone was sufficient to activate JNK independent of islet amyloid. Inhibition of islet amyloid formation with Congo Red reduced beta cell apoptosis and partially decreased JNK activation. JNK inhibitor treatment reduced beta cell apoptosis without affecting islet amyloid. Islet amyloid increased mRNA levels of markers of the extrinsic (Fas, Fadd) and intrinsic (Bim [also known as Bcl2l11]) apoptotic pathways, caspase 3 and the anti-apoptotic molecule Bclxl (also known as Bcl2l1) in a JNK-dependent manner. CONCLUSIONS/INTERPRETATION: Islet amyloid formation induces JNK activation, which upregulates predominantly pro-apoptotic signals in both extrinsic and intrinsic pathways, resulting in beta cell apoptosis.
Authors:
S L Subramanian; R L Hull; S Zraika; K Aston-Mourney; J Udayasankar; S E Kahn
Related Documents :
15585866 - Tlrs govern neutrophil activity in aspergillosis.
17157206 - Toll like receptors and acute allograft rejection.
17576036 - Glucocorticoids and the innate immune system: crosstalk with the toll-like receptor sig...
19922426 - Toll-like receptor-induced innate immune responses in non-parenchymal liver cells are c...
18272486 - Selective suicide of cross-presenting cd8+ dendritic cells by cytochrome c injection sh...
12388806 - Natural killer cell activation after infection with lactate dehydrogenase-elevating virus.
Publication Detail:
Type:  JOURNAL ARTICLE     Date:  2011-10-26
Journal Detail:
Title:  Diabetologia     Volume:  -     ISSN:  1432-0428     ISO Abbreviation:  -     Publication Date:  2011 Oct 
Date Detail:
Created Date:  2011-10-31     Completed Date:  -     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  0006777     Medline TA:  Diabetologia     Country:  -    
Other Details:
Languages:  ENG     Pagination:  -     Citation Subset:  -    
Affiliation:
Division of Metabolism, Endocrinology, and Nutrition, Department of Medicine, VA Puget Sound Health Care System and University of Washington, 1660 South Columbian Way, Seattle, WA, 98108, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Ubiquitin C-terminal hydrolase L1 is required for pancreatic beta cell survival and function in lipo...
Next Document:  A metabolomic study of low estimated GFR in non-proteinuric type 2 diabetes mellitus.