BACKGROUND: A high-carbohydrate diet leads to the metabolic syndrome (MetS), which leads to an increased risk for cardiovascular dysfunction; however, the effect of high-carbohydrate diets on systemic metabolism has not yet been fully determined. It has been observed that abnormal fatty acid metabolism and increased oxidative stress play a role in the pathogenesis of MetS-related cardiovascular diseases.
OBJECTIVE: To examine the effects of high sucrose intake on left ventricular contractility and structure of heart tissue.
METHODS: MetS was induced in male rats with drinking water supplemented with 32% sucrose for 16 weeks. Oral glucose tolerance test results and parameters related to insulin resistance were used to validate MetS.
RESULTS: Body weight and blood glucose levels were higher in the MetS group compared with age-matched controls. The increased serum leptin and triglyceride levels and decreased ghrelin levels further supported the existence of MetS in the MetS group. The ratio of total oxidant status to total antioxidant status measured in serum was also higher in the MetS group compared with the control group. The hemodynamic parameters of the MetS group, such as heart rate, and systolic and diastolic blood pressure levels, were markedly higher in the MetS group, while left ventricular developed pressure was significantly diminished with prolonged time course. Moreover, these functional alterations in cardiac preparations were further supported with structural changes such as significant increases in myofibril undulation and increased lipid droplets.
CONCLUSIONS: These data highlight the link between high carbohydrate intake, MetS and cardiac dysfunction, in part due to increased systemic oxidative stress and lipid deposition in the heart tissue.
