[Changes and relations of leptin, growth hormone and insulin during puberty in obese and non-obese children]

In order to study the regularity of changing leptin, growth hormone (GH) and insulin (INS) during puberty and their relationships, a group of 300 obese and 300 non-obese children, aged 10-15 were selected. Leptin level increased with age and then decreased in boys, but it had only increasing tendency in girls. The GH level increased and then decreased suddenly in all groups. There was no obvious regularity in the change of INS. Serum leptin and INS levels were higher (P < 0.01) in obese children than that in non-obese children, while GH levels were significantly lower (P < 0.01) in obese boys. Results also showed that GH was negatively correlated with leptin in boys (obese group: r = -0.74, P < 0.05; non-obese group: r = -0.69, P < 0.05) and positively correlated with leptin in girls (obese group: r = 0.58, P < 0.05; non-obese group: r = 0.67, P < 0.01). There was a positive correlation between INS and leptin in non-obese girls (r = 0.54, P < 0.05). It is concluded that leptin might play an important role during the initial stage of puberty in children and the effect of leptin on pubescent development in girls is greater compared with boys. The correlation between leptin and GH are gender dependent in boys and girls, which may cause the timing differences of sudden growth in boys and girls.