ESPE Abstracts

Orexigenic molecules such as ghrelin and neuropeptide Y (NPY) can contribute puberty as directly or indirectly. Our aim is to investigate the changes in the levels of orexigenic peptides ghrelin and neuropeptide Y at the onset of puberty in girls with idiopathic central precocious puberty (ICPP), premature thelarche (PT) and premature adrenarche (PA), and to determine their relationship with gonadotropins and anthropometric parameters.

Subjects and Methods: Eighty-four girls aged 24-96 months with signs of puberty such as breast budding, pubic and axillary hair and 24 prepubertal girls were included in this study. Prepubertal girls were the control group. The girls with breast budding were diagnosed with precocious puberty or PT according to Gonadotropin Releasing Hormone (GnRH) test, bone age, and basal follicle stimulating Hormone (FSH)/Luteinizing Hormone (LH) ratios. Only those with pubic and axillary hair were defined as premature adrenarche. Height and weight measured. Ghrelin and NPY concentrations were evaluated during diagnosis.

Results: There was no significant difference in NPY concentration between the 3 groups with pubertal findings and the control group (P>0.05). Ghrelin concentration differed between the four groups (P<0.05). Ghrelin concentration was significantly higher in girls with PT compared to girls with ICPP (P=0.023). No correlations were found between gonadotropins and both ghrelin and neuropeptide Y concentrations in three groups (P>0.05). The body weight standard deviation score (SDS) and body mass index SDS were significantly higher in girls with PA than in girls with PT and ICCP (P=0.011 and 0.024, respectively). No correlation was also found between neuropeptide Y and anthropometric parameters in all three groups (P>0.05). A positive significant correlation was found between ghrelin and body weight SDS in girls with premature thelarche (r:0.397, P=0.04).

Conclusion: Girls with PA were more overweight than girls with PT and ICCP in our study. However, we found that body weight increased as ghrelin concentration increased in girls with PT. Although we could not find a relationship between ghrelin and gonadotropin concentrations, the fact that ghrelin concentration is higher in girls with PT than in girls with ICCP may suggest that decreased ghrelin levels initiate pubertal progression through different mechanisms.