Beta-cell-targeted expression of a dominant-negative mutant of hepatocyte nuclear factor-1alpha in mice: diabetes model with beta-cell dysfunction partially rescued by nonglucose secretagogues
| Autor: | Winzell, Maria Sörhede, Pacini, Giovanni, Wollheim, Claes, Ahrén, Bo |
|---|---|
| Rok vydání: | 2004 |
| Předmět: |
Blood Glucose
Male Transcription Factors/genetics Palmitic Acid Mice Transgenic Insulin/analysis/secretion Arginine Potassium Chloride Islets of Langerhans/drug effects/physiology/secretion Islets of Langerhans Mice Potassium Chloride/pharmacology Insulin Secretion Animals Insulin Carbachol/pharmacology Hepatocyte Nuclear Factor 1-alpha ddc:612 Genes Dominant Blood Glucose/metabolism Nuclear Proteins Glucose/pharmacology Rats Nuclear Proteins/genetics DNA-Binding Proteins Glucose Hepatocyte Nuclear Factor 1 Mutation Carbachol Arginine/pharmacology Palmitic Acid/pharmacology DNA-Binding Proteins/genetics Transcription Factors |
| Zdroj: | Diabetes, Vol. 53 Suppl 3 (2004) pp. S92-6 |
| ISSN: | 0012-1797 |
| Popis: | We studied islet function in mice with beta-cell-targeted expression of a dominant-negative mutant of hepatocyte nuclear factor (HNF)-1alpha. At age 2-3 months, anesthetized transgenic and wild-type male mice underwent an intravenous glucose (1 g/kg) tolerance test (IVGTT). It was found that transgenic mice had an abolished insulin response in association with severe glucose intolerance. In other tests, the 5-min insulin response to intravenous arginine was impaired by 79% (P=0.032) and the 15-min insulin response to gastric glucose was suppressed by 97% (P=0.006). In islets incubated for 60 min, the insulin response to glucose (3.3-22.2 mmol/l) was impaired by >80% in transgenic mice. In contrast, insulin responses to nonglucose secretagogues were only partially suppressed (to GLP-1 [100 nmol/l] by 40%, to carbachol [1 micromol/l] by 20%, and to palmitate [0.5 mmol/l] by 15%), whereas the response to depolarization by KCl (50 mmol/l) was not reduced. Finally, the IVGTT data insulin sensitivity in transgenic mice was not significantly different from that of wild-type mice. Thus, mice with targeted suppression of beta-cell HNF-1alpha represent a good diabetes model exhibiting severely impaired insulin secretion after glucose with marked glucose intolerance. In contrast, the insulin responses to nonglucose stimuli are not suppressed when the islet insulin content is taken into account. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|