Abstract 17091: High Saturated Fat Intake Improves Survival in Genetic Cardiomyopathy Compared to a High Polyunsaturated Fat Diet or a Low Fat Diet

Abstract

Surprisingly, a high fat diet comprised mainly of saturated fatty acids improves LV function and survival in rat models of heart failure induced by hypertension or myocardial infarction. The mechanism for this effect is not clear, nor is it known if a similar effect occurs with a high fat diet composed of plant derived polyunsaturated fatty acids (PUFA), or in genetic cardiomyopathies. We determined if survival in cardiomyopathic hamsters (Bio TO-2 strain) is prolonged by a high fat diet compared to a low fat diet (see table). Further, we compared the effect of high fat diets enriched with either saturated fat (palmitate and stearate), or PUFAs from plant sources(primarily linoleic and α-linolenic acids). Cardiomyopathic hamsters (6 wks old) were fed either a Low Fat diet; a High PUFA diet, or a High Saturated Fat diet. Survival was assessed (n=30/group), and subgroups were evaluated at 30 wks of age (n=12/group) for LV and mitochondrial function. The diet has no effect on LV function as assessed by echocardiography, and there was no difference in body weight or LV mass. Since there is impaired mitochondrial function in heart failure and dietary lipid composition might positively impact mitochondrial function, isolated mitochondria were assessed. Respiration and Ca 2+ -induced mitochondrial permeability transition were unaffected by diet. On the other hand, the high PUFA diet increased fat pad mass compared with the two other cardiomyopathic groups and elevated plasma free fatty acid concentration (p<0.05). Importantly, there was a significant increase in survival in the high saturated sat group compared to the either the low fat or the high PUFA groups after 16 months of treatment (p<0.0001). These results show that a high fat diet comprised largely of long chain saturated fatty acids increase survival in cardiomyopathic hamsters compared to either a low fat diet or a high fat diet comprised of PUFA from plant sources. The effect was independent of improved mitochondrial function.