Back to Search
Start Over
Regulation of insulin secretion and expression of SUR1 gene by chronic exposure to free fatty acids in rat pancreatic beta cells.
- Source :
-
Journal of Huazhong University of Science and Technology. Medical sciences = Hua zhong ke ji da xue xue bao. Yi xue Ying De wen ban = Huazhong keji daxue xuebao. Yixue Yingdewen ban [J Huazhong Univ Sci Technolog Med Sci] 2004; Vol. 24 (4), pp. 358-60, 364. - Publication Year :
- 2004
-
Abstract
- To study the effects of free fatty acids on insulin secretion and expression of SUR1 gene in rat pancreatic B cells in vitro, and to explore the molecular mechanisms in lipotoxicity inducing insulin secretion dysfunction, pancreatic islet cells were isolated and digested from male SD rats. Purified islets were incubated with either 0.25 mmol/L palmitate or 0.125 mmol/L oleate for 48 h in vitro. Then islets were stimulated with either 5.6 mmol/L or 16.7 mmol/L glucose for 1 h. Insulin release was measured by using radioimmunoassay, and the expression of SUR1 gene mRNA was quantified by reserve transcription-polymerase chain reaction (RT-PCR). The islets exposed to both palmitate and oleate for 48 h showed an increased basal and a decreased glucose-indused insulin release as compared with control islets. Palmitate increased basal insulin secretion by 110% (P< 0.01), decreased glucose stimulated insulin secretion by 43% (P<0.01); while oleate increased basal insulin secretion by 80% (P<0.01) and decreased glucose stimulated insulin secretion by 32 % (P<0.05). RT-PCR showed that oleate significantly suppressed SUR1 gene expression by 64 % (P<0.01) as compared with the control group, while palmitate group manifested a light decrease of 15% (P>0.05) of SUR1 gene expression. Our results suggested that chronic exposure to free fatty acids of pancreatic beta cells inhibited glucose stimulated insulin secretion. Regulation of SUR1 gene expression may be involved in such effects, which may also be one of the molecular mechanisms in lipotoxocity inducing beta cells secretion dysfunction.
- Subjects :
- ATP-Binding Cassette Transporters genetics
Animals
Cells, Cultured
Insulin Secretion
Islets of Langerhans physiology
Male
Potassium Channels genetics
Potassium Channels, Inwardly Rectifying genetics
RNA, Messenger biosynthesis
RNA, Messenger genetics
Rats
Rats, Sprague-Dawley
Receptors, Drug genetics
Sulfonylurea Receptors
ATP-Binding Cassette Transporters biosynthesis
Fatty Acids pharmacology
Insulin metabolism
Islets of Langerhans drug effects
Potassium Channels biosynthesis
Potassium Channels, Inwardly Rectifying biosynthesis
Receptors, Drug biosynthesis
Subjects
Details
- Language :
- English
- ISSN :
- 1672-0733
- Volume :
- 24
- Issue :
- 4
- Database :
- MEDLINE
- Journal :
- Journal of Huazhong University of Science and Technology. Medical sciences = Hua zhong ke ji da xue xue bao. Yi xue Ying De wen ban = Huazhong keji daxue xuebao. Yixue Yingdewen ban
- Publication Type :
- Academic Journal
- Accession number :
- 15587398
- Full Text :
- https://doi.org/10.1007/BF02861867