The effects of obesity-associated insulin resistance on mRNA expression of peroxisome proliferator-activated receptor-γ target genes, in dogs
| Autor: | Véronique Leray, Patrick Nguyen, Constance Gayet, Brigitte Siliart, Masayuki Saito |
|---|---|
| Rok vydání: | 2007 |
| Předmět: |
Blood Glucose
Leptin medicine.medical_specialty Gene Expression Medicine (miscellaneous) Adipose tissue Adipokine Peroxisome proliferator-activated receptor Intra-Abdominal Fat Weight Gain Dogs Insulin resistance Internal medicine medicine Animals Insulin Obesity RNA Messenger Muscle Skeletal Triglycerides chemistry.chemical_classification Lipoprotein lipase Glucose Transporter Type 4 Nutrition and Dietetics biology Adiponectin Tumor Necrosis Factor-alpha nutritional and metabolic diseases medicine.disease PPAR gamma Lipoprotein Lipase Endocrinology chemistry biology.protein Insulin Resistance hormones hormone substitutes and hormone antagonists GLUT4 |
| Zdroj: | British Journal of Nutrition. 98:497-503 |
| ISSN: | 1475-2662 0007-1145 |
| DOI: | 10.1017/s000711450772514x |
| Popis: | Visceral adipose tissue and skeletal muscle have central roles in determining whole-body insulin sensitivity. The peroxisome proliferator-activated receptor-gamma (PPARgamma) is a potential mediator of insulin sensitivity. It can directly modulate the expression of genes that are involved in glucose and lipid metabolism, including GLUT4, lipoprotein lipase (LPL) and adipocytokines (leptin and adiponectin). In this study, we aimed to determine the effects of obesity-associated insulin resistance on mRNA expression of PPARgamma and its target genes. Dogs were studied when they were lean and at the end of an overfeeding period when they had reached a steady obese state. The use of a sensitive, real-time PCR assay allowed a relative quantification of mRNA expression for PPARgamma, LPL, GLUT4, leptin and adiponectin, in adipose tissue and skeletal muscle. In visceral adipose tissue and/or skeletal muscle, mRNA expression of PPARgamma, LPL and GLUT4 were at least 2-fold less in obese and insulin-resistant dogs compared with the same animals when they were lean and insulin-sensitive. The mRNA expression and plasma concentration of leptin was increased, whereas the plasma level and mRNA expression of adiponectin was decreased, by obesity. In adipose tissue, PPARgamma expression was correlated with leptin and adiponectin. These findings, in an original model of obesity induced by a prolonged period of overfeeding, showed that insulin resistance is associated with a decrease in PPARgamma mRNA expression that could dysregulate expression of several genes involved in glucose and lipid metabolism. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|