Left ventricular hypertrophy induced by overnutrition early in life

Background and aims: Human overnutrition has caused a rise in the prevalence of obesity in recent years. In addition to the deleterious effects of obesity during childhood, the long-term effects in adulthood have also been described. For instance, cardiovascular diseases, particularly left ventricular hypertrophy, and type 2 diabetes are among the diseases associated with a history of obesity. However, it remains uncertain during which period of life this association is established. Several authors have suggested that the early period of life is critical for the emergence of cardiac disorders. Methods and results: In this study, we examined the impact of overnutrition on the heart morphology and stereology of obese animals using an experimental model to induce an overweight phenotype. In these animals, overfeeding during lactation was able to induce a significant increase in body weight and visceral fat starting at the 10th day of life, and this increased weight persisted until 21 days of age. Impairments in triglyceride levels and cholesterol were also observed in these animals. Moreover, an increased heart weight/tibia length ratio was observed, indicating an enlarged heart. The overfed animals also had left ventricular hypertrophy with an increased area of cardiomyocytes and a decreased vessel density. Conclusions: Our findings showed that overnutrition during early life induced obesity and cardiac hypertrophy in the pups, perhaps due to a decrease in the intramyocardial vessel. (c) 2009 Elsevier B.V. All rights reserved.