Cholesteryl ester transfer protein expression is down-regulated in hyperinsulinemic transgenic mice
Autor: | P.R. Patricio, Everardo M. Carneiro, E.J.B. Bighetti, J.A. Berti, A.C. Casquero, Helena C. F. Oliveira, Antonio C. Boschero |
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Rok vydání: | 2003 |
Předmět: |
medicine.medical_specialty
medicine.medical_treatment Lipoproteins experimental diabetes cholesteryl ester transfer protein gene expression lipoprotein lipase Down-Regulation Mice Transgenic QD415-436 Carbohydrate metabolism Biochemistry chemistry.chemical_compound Mice Endocrinology Downregulation and upregulation Internal medicine Hyperinsulinism Cholesterylester transfer protein medicine Hyperinsulinemia Animals Humans Insulin RNA Messenger triglycerides Glycoproteins biology Triglyceride Cell Biology medicine.disease Streptozotocin Cholesterol Ester Transfer Proteins carbohydrates (lipids) Glucose chemistry Gene Expression Regulation Liver Cholesteryl ester biology.protein Body Composition lipids (amino acids peptides and proteins) hyperglycemia Cholesterol Esters Carrier Proteins medicine.drug |
Zdroj: | Journal of Lipid Research, Vol 44, Iss 10, Pp 1870-1876 (2003) |
ISSN: | 0022-2275 |
Popis: | Cholesteryl ester transfer protein (CETP) mediates cholesteryl ester (CE) and triglyceride redistribution among plasma lipoproteins. In this work, we investigated whether varying levels of insulin regulate the CETP expression in vivo. Insulin deficiency [streptozotocin (STZ) injection], and hyperinsulinemia (insulin injections, 14 days) were induced in transgenic mice expressing a human CETP minigene flanked by its natural regulatory sequences. Glucose supplementation was provided to the hyperinsulinemic group (INS+GLUC) and to an extra group of mice (GLUC). In the STZ group, endogenous CE transfer rate, plasma CETP, and hepatic CETP mRNA levels were enhanced 3.0-, 1.5-, and 2.5-fold, respectively, as compared with controls. Insulin replacement in STZ mice normalized their glycemia and liver mRNA levels. Higher plasma CETP levels were observed in GLUC mice, which were decreased in INS+GLUC mice. Hepatic CETP mRNA was not altered in GLUC mice and was reduced by one-third in INS+GLUC mice. These results show that: 1) STZ treatment increases CETP plasma levels and liver mRNA expression; 2) diet glucose supplementation increases plasma CETP levels but does not change liver mRNA abundance; and 3) daily insulin injections blunt the glucose-stimulated CETP expression by reducing its liver mRNA levels. These data suggest that insulin down-regulates CETP gene expression. |
Databáze: | OpenAIRE |
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