title: Aerobic exercise improves microvascular dysfunction in fructose fed hamsters.
abstract: Fructose is a major diet component directly related to severe damages to the microcirculation and to diseases such as obesity, diabetes and hypertension to which physical activity is pointed out as an important non-pharmacological treatment since its positive effects precede anthropometric improvements. In this study we have investigated the effects of a light/moderate aerobic exercise training (AET) on microcirculatory dysfunction elicited by carbohydrate overload during a period of 5 months. Male hamsters (Mesocricetus auratus) whose drinking water was substituted (F) or not (C) by 10% fructose solution, during 20 weeks, associated or not to AET in the last 4 weeks (EC and EF subgroups) had their microcirculatory function evaluated on the cheek pouch preparation, glucose and insulin tolerance (GTT and ITT) tested. Arterial blood was collected for pO2, pCO2, HCO3(-), pH, total CO2, saturated O2 and lactate determinations. Liver fragments were observed using an electron microscope. Microcirculatory responses to acetylcholine [Ach, an endothelium-dependent vasodilator; 10(-8)M - *123.3±7.5% (C), 119.5±1.3% (EC), *98.1±3.2% (F) and 133.6±17.2% (EF); 10(-6)M - *133.0±4.1% (C), 135.6±4.3% (EC), *103.4±4.3% (F) and 134.1±5.9% (EF); 10(-4)M - *167.2±5.0% (C), 162.8±5.4% (EC), *123.8±6.3% (F) and 140.8±5.0% (EF)] and to sodium nitroprusside [SNP, an endothelium-independent vasodilator; 10(-8)M - 118.8±6.8% (C), 114.0±5.0% (EC), 100.2±2.9% (F), 104.9±4.4% (EF); 10(-6)M - 140.6±11.7% (C), 141.7±5.5% (EC), 125.0±4.7% (F), 138.3±2.8% (EF); 10(-4)M - 150.4±10.9% (C), 147.9±6.5% (EC), 139.2±7.3% (F), 155.9±4.7% (EF)] and macromolecular permeability increase induced by 30 min ischemia/reperfusion (I/R) procedure [14.4±3.5 (C), 30.0±1.9 (EC), *112.0±8.8 (F) and *22.4±0.9 leaks/cm(2) (EF)] have shown that endothelium-dependent vasodilatation was significantly reduced and I/R induced macromolecular permeability augmented in sedentary fructose (F) subgroup and both improved after AET. Electron microscopy analysis of the liver showed significant differences between exercised and sedentary subgroups with greater amount of glycogen in F subgroups compared to other ones. No significant changes on mean arterial pressure, heart rate or blood gase between subgroups could be detected. Our results point out that AET could normalize microcirculatory dysfunction elicited by long term substitution of drinking water by 10% fructose solution.
authors.affiliation: Laboratory for Clinical and Experimental Research on Vascular Biology (BioVasc), Biomedical Center, State University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil. Electronic address: beatrizcsb@gmail.com.
authors.forename: B C S
authors.initials: BC
authors.lastname: Boa
authors.affiliation: Nutrition Institute, Federal University of Rio de Janeiro, Campus Macaé, Macaé, RJ, Brazil.
authors.forename: R R
authors.initials: RR
authors.lastname: Costa
authors.affiliation: Laboratory for Clinical and Experimental Research on Vascular Biology (BioVasc), Biomedical Center, State University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
authors.forename: M G C
authors.initials: MG
authors.lastname: Souza
authors.affiliation: Laboratory for Clinical and Experimental Research on Vascular Biology (BioVasc), Biomedical Center, State University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
authors.forename: F Z G A
authors.initials: FZ
authors.lastname: Cyrino
authors.affiliation: Laboratory for Clinical and Experimental Research on Vascular Biology (BioVasc), Biomedical Center, State University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
authors.forename: L S
authors.initials: LS
authors.lastname: Paes
authors.affiliation: Laboratory for Clinical and Experimental Research on Vascular Biology (BioVasc), Biomedical Center, State University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
authors.forename: M L
authors.initials: ML
authors.lastname: Miranda
authors.affiliation: Department of Histology and Embryology, Laboratory of Electron Microscopy, Biomedical Center, State University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
authors.forename: J J
authors.initials: JJ
authors.lastname: Carvalho
authors.affiliation: Laboratory for Clinical and Experimental Research on Vascular Biology (BioVasc), Biomedical Center, State University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
authors.forename: E
authors.initials: E
authors.lastname: Bouskela
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000097:blood; D002199:Capillary Permeability; D002610:Cheek / Q000098:blood supply*; D019422:Dietary Sucrose; D004195:Disease Models, Animal; D005081:Exercise Therapy; D006003:Glycogen / Q000378:metabolism; D008099:Liver / Q000378:metabolism / Q000648:ultrastructure; D008297:Male; D008647:Mesocricetus; D008833:Microcirculation / Q000187:drug effects; D055806:Microvessels / Q000187:drug effects / Q000378:metabolism / Q000503:physiopathology*; D015427:Reperfusion Injury / Q000378:metabolism / Q000503:physiopathology; D013997:Time Factors; D014652:Vascular Diseases / Q000097:blood / Q000139:chemically induced / Q000503:physiopathology / Q000628:therapy*; D014664:Vasodilation; D014665:Vasodilator Agents / Q000494:pharmacology
chemical_list: D015415:Biomarkers; D019422:Dietary Sucrose; D014665:Vasodilator Agents; D006003:Glycogen
keywords: 10% fructose drinking solution; Aerobic exercise; Cheek pouch preparation; Hamsters; Microcirculation