Exercise training prevents diastolic dysfunction induced by metabolic syndrome in rats

Clinics (Sao Paulo). 2012 Jul;67(7):815-20. doi: 10.6061/clinics/2012(07)18.

Abstract

Objective: High fructose consumption contributes to the incidence of metabolic syndrome and, consequently, to cardiovascular outcomes. We investigated whether exercise training prevents high fructose diet-induced metabolic and cardiac morphofunctional alterations.

Methods: Wistar rats receiving fructose overload (F) in drinking water (100 g/l) were concomitantly trained on a treadmill (FT) for 10 weeks or kept sedentary. These rats were compared with a control group (C). Obesity was evaluated by the Lee index, and glycemia and insulin tolerance tests constituted the metabolic evaluation. Blood pressure was measured directly (Windaq, 2 kHz), and echocardiography was performed to determine left ventricular morphology and function. Statistical significance was determined by one-way ANOVA, with significance set at p<0.05.

Results: Fructose overload induced a metabolic syndrome state, as confirmed by insulin resistance (F: 3.6 ± 0.2 vs. C: 4.5 ± 0.2 mg/dl/min), hypertension (mean blood pressure, F: 118 ± 3 vs. C: 104 ± 4 mmHg) and obesity (F: 0.31 ± 0.001 vs. C: 0.29 ± 0.001 g/mm). Interestingly, fructose overload rats also exhibited diastolic dysfunction. Exercise training performed during the period of high fructose intake eliminated all of these derangements. The improvements in metabolic parameters were correlated with the maintenance of diastolic function.

Conclusion: The role of exercise training in the prevention of metabolic and hemodynamic parameter alterations is of great importance in decreasing the cardiac morbidity and mortality related to metabolic syndrome.

MeSH terms

  • Animals
  • Diastole / physiology
  • Disease Models, Animal
  • Fructose / adverse effects
  • Male
  • Metabolic Syndrome / complications*
  • Metabolic Syndrome / physiopathology
  • Physical Conditioning, Animal / physiology*
  • Rats
  • Rats, Wistar
  • Sweetening Agents / adverse effects
  • Ventricular Dysfunction, Left / etiology
  • Ventricular Dysfunction, Left / physiopathology
  • Ventricular Dysfunction, Left / prevention & control*

Substances

  • Sweetening Agents
  • Fructose