Testosterone modulates serum leptin concentrations in a male patient with hypothalamic hypogonadism

Serial measurements of body mass index (BMI), serum concentrations of testo sterone (T), estradiol (E) and leptin (L) were performed before and after g onadotropin (Gn) therapy in an 18-year-old male subject (BMI 25.4 kg/m(2)) with idiopathic hypothalamic hypogonadism (IHH). We also measured the BMI a nd serum concentrations of L in 99 age-matched healthy subjects. Serum L co rrelated significantly with BMI in control subjects (r=0.84, p<0.0001). Bas eline serum concentrations of L in our case were markedly high and both T a nd E were very low, but On therapy resulted in a gradual decrease in L and improvement in T and E, finally reaching the control levels of BMI-matched subjects. Our results demonstrate that T is a powerful negative modulator o f serum L independent of BMI in conditions associated with low T levels, su ch as IHH. (C) 2000, Editrice Kurtis.