IGF1 and obesity due to melanocortin 4 receptor deficiency: In addition, various dietary (e.g., particular nutrient-depleted or enriched, semi- or chemically-defined) manipulations and well-conserved (e.g., insulin/IGF, TOR and sirtuin) signaling pathways have been described and characterized for studies of longevity and aging-related diseases (e.g., obesity, cardiomyopathy and memory disability) in flies [20, 22, 27, 29, 30, 47-55].