La mantención de peso en humanos: ¿podría ser equivalente a la restricción calórica de los modelos animales?
de la Maza C,M Pía
Background: Energy restriction (ER) extends life span in animals, by decreasing oxidative stress. Aim: To compare adiposity, metabolic variables and DNA oxidative damage, among adults, reporting a constant body weight (weight maintainers), versus those reporting a progressive increase (weight gainers). Subjects and Methods: Clinical history, dietary recall, anthropometric measures, abdominal CT scan and fasting blood samples (to measure lipoproteins, glucose and insulin), were obtained in 44 males. These subjects were classified as weight maintainers if they had a change in weight of 3 kg or less in the last 10 years, or weight gainers, if they had a weight increment of more than 6 kg in the same lapse. Oxidative damage was assessed by 8-hydroxydeoxyguanosine (8-OHdG), in DNA extracted from circulating lymphocytes, in 5 weight maintainers, 8 weight gainers and 5 healthy elders. Results: Energy intake was 18% higher in weight gainers (p <0.01). Adiposity and central fat were higher among weight gainers (p <0.01). Abdominal fat correlated with serum lipoproteins, glucose and insulin sensitivity, assessed by the Homeostasis Model Assessment (HOMA). 8-OHdG levels did not differ between groups. Conclusions: The analysis of weight change based on the clinical history correlates with actual body composition, thus it may be a reliable indicator of long term energy intake. This method could be comparable to weight clamp models employed in animals to study aging (Rev Méd Chile 2004; 132: 1166-72)