Effects of Recombinant Leptin Therapy in a Child with Congenital Leptin Deficiency

Severely obese (ob/ob) mice are deficient in the adipocyte-derived hormone leptin, which acts on the hypothalamus to control appetite and energy expenditure.1 The administration of leptin to these mice corrects their obesity by reducing their food intake and increasing their energy expenditure.2–4 These mice also have hyperinsulinemia, corticosterone excess, and infertility, which also are reversed by treatment with leptin.5 In humans, serum leptin concentrations, in general, correlate positively with indexes of obesity.6,7 We previously described two cousins with severe, early-onset obesity and undetectable serum leptin concentrations who were homozygous for a frame-shift mutation in the leptin . . .