SCD and obesity due to melanocortin 4 receptor deficiency: Oleic acid, which is the main product of Scd-1 reaction and associates Scd-1 with the development of obesity and the metabolic syndrome [20], was significantly decreased in SFD-fed ovx KO mice (* p < 0.05), making all three main MUFAs reduced upon Sirt3 and ovary hormone deficiency.