Linked Life Data

15531508

Source:http://linkedlifedata.com/resource/pubmed/id/15531508

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
2004-11-8
pubmed:abstractText
Several properties of pancreatic beta-cells in type 2 diabetes (T2D) were studied by using islets isolated from T2D subjects. Moreover, because metformin has protective effects on nondiabetic beta-cells exposed to high glucose or free fatty acid levels, we investigated its direct action on T2D islet cells. Diabetic islets were characterized by reduced insulin content, decreased amount of mature insulin granules, impaired glucose-induced insulin secretion, reduced insulin mRNA expression, and increased apoptosis with enhanced caspase-3 and -8 activity. These alterations were associated with increased oxidative stress, as shown by higher nitrotyrosine concentrations, increased expression of protein kinase C-beta2 and nicotinamide adenine dinucleotide phosphate reduced-oxidase, and changes in mRNA expression of manganese- superoxide dismutase, Cu/Zn-superoxide dismutase, catalase, and glutathione peroxidase. Twenty-four-hour incubation of T2D islets with metformin was associated with increased insulin content, increased number and density of mature insulin granules, improved glucose-induced insulin release, and increased insulin mRNA expression. Moreover, apoptosis was reduced, with concomitant decrease of caspase-3 and -8 activity. These changes were accompanied by reduction or normalization of several markers of oxidative stress. Thus, T2D islets have several functional and survival defects, which can be ameliorated by metformin; the beneficial effects of the drug are mediated, at least in part, by a reduction of oxidative stress.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0021-972X
pubmed:author
pubmed:issnType
Print
pubmed:volume
89
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
5535-41
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Pancreatic islets from type 2 diabetic patients have functional defects and increased apoptosis that are ameliorated by metformin.
pubmed:affiliation
Department of Endocrinology and Metabolism and Diabetes, Transplant Unit, University of Pisa, Italy. marchant@immr.med.unipi.it.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't