Linked Life Data

11147797

Source:http://linkedlifedata.com/resource/pubmed/id/11147797

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2001-1-5
pubmed:abstractText
Glucotoxicity and lipotoxicity contribute to the impaired beta-cell function observed in type 2 diabetes. Here we examine the effect of saturated and unsaturated fatty acids at different glucose concentrations on beta-cell proliferation and apoptosis. Adult rat pancreatic islets were cultured onto plates coated with extracellular matrix derived from bovine corneal endothelial cells. Exposure of islets to saturated fatty acid (0.5 mmol/l palmitic acid) in medium containing 5.5, 11.1, or 33.3 mmol/l glucose for 4 days resulted in a five- to ninefold increase of beta-cell DNA fragmentation. In contrast, monounsaturated palmitoleic acid alone (0.5 mmol/l) or in combination with palmitic acid (0.25 or 0.5 mmol/l each) did not affect DNA fragmentation. Increasing concentrations of glucose promoted beta-cell proliferation that was dramatically reduced by palmitic acid. Palmitoleic acid enhanced the proliferation activity in medium containing 5.5 mmol/l glucose but had no additional effect at higher glucose concentrations (11.1 and 33.3 mmol/l). The cell-permeable ceramide analog C2-ceramide mimicked both the palmitic acid-induced beta-cell apoptosis and decrease in proliferation. Moreover, the ceramide synthetase inhibitor fumonisin B1 blocked the deleterious effects of palmitic acid on beta-cell viability. Additionally, palmitic acid but not palmitoleic acid decreased the expression of the mitochondrial adenine nucleotide translocator and induced release of cytochrome c from the mitochondria into the cytosol. Finally, palmitoleic acid improved beta-cell-secretory function that was reduced by palmitic acid. Taken together, these results suggest that the lipotoxic effect of the saturated palmitic acid involves an increased apoptosis rate coupled with reduced proliferation capacity of beta-cells and impaired insulin secretion. The deleterious effect of palmitate on beta-cell turnover is mediated via formation of ceramide and activation of the apoptotic mitochondrial pathway. In contrast, the monounsaturated palmitoleic acid does not affect beta-cell apoptosis, yet it promotes beta-cell proliferation at low glucose concentrations, counteracting the negative effects of palmitic acid as well as improving beta-cell function.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0012-1797
pubmed:author
pubmed:issnType
Print
pubmed:volume
50
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
69-76
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed-meshheading:11147797-Animals, pubmed-meshheading:11147797-Apoptosis, pubmed-meshheading:11147797-Cell Division, pubmed-meshheading:11147797-Ceramides, pubmed-meshheading:11147797-Culture Techniques, pubmed-meshheading:11147797-Cytochrome c Group, pubmed-meshheading:11147797-Fatty Acids, pubmed-meshheading:11147797-Fatty Acids, Monounsaturated, pubmed-meshheading:11147797-Fatty Acids, Unsaturated, pubmed-meshheading:11147797-Glucose, pubmed-meshheading:11147797-Insulin, pubmed-meshheading:11147797-Islets of Langerhans, pubmed-meshheading:11147797-Male, pubmed-meshheading:11147797-Mitochondrial ADP, ATP Translocases, pubmed-meshheading:11147797-Palmitic Acid, pubmed-meshheading:11147797-Rats, pubmed-meshheading:11147797-Rats, Sprague-Dawley, pubmed-meshheading:11147797-Signal Transduction
pubmed:year
2001
pubmed:articleTitle
Distinct effects of saturated and monounsaturated fatty acids on beta-cell turnover and function.
pubmed:affiliation
Division of Endocrinology and Diabetes, University Hospital, Zurich, Switzerland.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't