Endothelial and vascular dysfunctions and insulin resistance in rats fed a high-fat, high-sucrose diet
| Autor: | Frédéric Bourgoin, Maryse Pitre, Hélène Bachelard, André Nadeau, Richard Larivière, Mylène Badeau, Sébastien Mélançon |
|---|---|
| Rok vydání: | 2008 |
| Předmět: |
Male
Sucrose medicine.medical_specialty Endothelium Physiology medicine.medical_treatment Blotting Western Fluorescent Antibody Technique Blood Pressure Deoxyglucose Fatty Acids Nonesterified Biology Rats Sprague-Dawley Insulin resistance Heart Rate Physiology (medical) Internal medicine medicine Hyperinsulinemia Animals Insulin Obesity Vascular Diseases Endothelial dysfunction Triglycerides Vascular tissue Endothelin-1 Body Weight Organ Size Glucose clamp technique medicine.disease Dietary Fats Diet Rats medicine.anatomical_structure Endocrinology Glucose Clamp Technique Vascular resistance Tyrosine Vascular Resistance Endothelium Vascular Insulin Resistance Cardiology and Cardiovascular Medicine |
| Zdroj: | American Journal of Physiology-Heart and Circulatory Physiology. 295:H1044-H1055 |
| ISSN: | 1522-1539 0363-6135 |
| DOI: | 10.1152/ajpheart.00516.2008 |
| Popis: | This study was designed to examine the effects of a high-fat, high-sucrose (HFHS) diet on vascular and metabolic actions of insulin. Male rats were randomized to receive an HFHS or regular chow diet for 4 wk. In a first series of experiments, the rats had pulsed Doppler flow probes and intravascular catheters implanted to measure blood pressure, heart rate, and regional blood flows. Insulin sensitivity and vascular responses to insulin were assessed during a euglycemic hyperinsulinemic clamp performed in conscious rats. In a second series of experiments, new groups of rats were used to examine skeletal muscle glucose transport activity and to determine in vitro vascular reactivity, endothelial nitric oxide synthase (eNOS) protein expression in muscle and vascular tissues and endothelin content, nitrotyrosine formation, and NAD(P)H oxidase protein expression in vascular tissues. The HFHS-fed rats displayed insulin resistance, hyperinsulinemia, hypertriglyceridemia, hyperlipidemia, elevated blood pressure, and impaired insulin-mediated renal and skeletal muscle vasodilator responses. A reduction in endothelium-dependent vasorelaxation, accompanied by a decreased eNOS protein expression in muscles and blood vessel endothelium, and increased vascular endothelin-1 protein content were also noted in HFHS-fed rats compared with control rats. Furthermore, the HFHS diet induced a reduced insulin-stimulated glucose transport activity in muscles and increased levels of NAD(P)H oxidase protein and nitrotyrosine formation in vascular tissues. These findings support the importance of eNOS protein in linking metabolic and vascular disease and indicate the ability of a Westernized diet to induce endothelial dysfunction and to alter metabolic and vascular homeostasis. |
| Databáze: | OpenAIRE |
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