title: Physical exercise restores microvascular function in obese rats with metabolic syndrome.
abstract: BACKGROUND
  Obesity and metabolic syndrome are related to systemic functional microvascular alterations, including a significant reduction in microvessel density. The aim of this study was to investigate the effects of exercise training on functional capillary density in the skeletal muscle and skin of obese rats with metabolic syndrome.
  
  
  METHODS
  We used male Wistar-Kyoto rats that had been fed a standard commercial diet (CON) or high-fat diet (HFD) for 32 weeks. Animals receiving the HFD were randomly divided into sedentary (HFD+SED) and training groups (HFD+TR) at the 20(th) week. After 12 weeks of aerobic treadmill training, the maximal oxygen uptake (VO2max); hemodynamic, biochemical, and anthropometric parameters; and functional capillary density were assessed. In addition, a maximal exercise test was performed.
  
  
  RESULTS
  Exercise training increased the VO2max (69 ± 3 mL/kg per min) and exercise tolerance (30 ± 1 min) compared with the HFD+SED (41 ± 6 mL/kg per min, P < 0.05 and 16 ± 1 min, P < 0.001) and with the CON (52 ± 7 mL/kg per min and 18 ± 1 min, P < 0.05) groups. The HFD+TR group also showed reduced retroperitoneal fat (0.03 ± 0.00 vs. 0.05 ± 0.00 gram/gram, P < 0.001), epididymal fat (0.01 ± 0.00 vs. 0.02 ± 0.00 gram/gram, P < 0.001), and systolic blood pressure (127 ± 2 vs. 150 ± 2 mmHg, P<0.001). The HFD+TR group also demonstrated improved glucose tolerance, as evaluated by an intraperitoneal glucose tolerance test, fasting plasma glucose levels (5.0 ± 0.1 vs. 6.4 ± 0.2 mmol/L, P<0.001) and fasting plasma insulin levels (26.5 ± 2.3 vs. 38.9 ± 3.7 μIU/mL, P < 0.05). Glucose tolerance did not differ between HFD+TR and CON groups. Exercise training also increased the number of spontaneously perfused capillaries in the skeletal muscle (252 ± 9 vs. 207 ± 9 capillaries/mm(2)) of the training group compared with that in the sedentary animals (260 ± 15 capillaries/mm(2)).
  
  
  CONCLUSIONS
  These results demonstrate that exercise training reverses capillary rarefaction in our experimental model of metabolic syndrome and obesity.
authors.affiliation: 1 Laboratory of Cardiovascular Investigation, Oswaldo Cruz Institute , FIOCRUZ, Rio de Janeiro, RJ, Brazil .
authors.forename: Marcus Vinicius
authors.initials: MV
authors.lastname: Machado
authors.forename: Aline Bomfim
authors.initials: AB
authors.lastname: Vieira
authors.forename: Alessandro Rodrigues
authors.initials: AR
authors.lastname: Nascimento
authors.forename: Rômulo Lanza
authors.initials: RL
authors.lastname: Martins
authors.forename: Julio Beltrame
authors.initials: JB
authors.lastname: Daleprane
authors.forename: Marcos Adriano
authors.initials: MA
authors.lastname: Lessa
authors.forename: Eduardo
authors.initials: E
authors.lastname: Tibiriçá
mesh_terms: D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D001823:Body Composition; D001835:Body Weight; D059305:Diet, High-Fat / Q000009:adverse effects; D004195:Disease Models, Animal; D006439:Hemodynamics; D007333:Insulin Resistance; D008297:Male; D024821:Metabolic Syndrome / Q000150:complications* / Q000503:physiopathology / Q000628:therapy*; D055806:Microvessels / Q000473:pathology / Q000503:physiopathology*; D018482:Muscle, Skeletal / Q000098:blood supply; D009765:Obesity / Q000150:complications* / Q000503:physiopathology / Q000628:therapy*; D010101:Oxygen Consumption; D010805:Physical Conditioning, Animal; D051381:Rats; D011921:Rats, Inbred WKY; D012867:Skin / Q000098:blood supply
chemical_list: D001786:Blood Glucose