Serum kisspeptin levels in Korean girls with central precocious puberty.

Central precocious puberty (CPP) is caused by premature activation of hypothalamic gonadotropin-releasing hormone (GnRH) secretion. Kisspeptin and G-protein coupled receptor-54 system is the essential gatekeeper of the reproductive system, playing a key role in the activation of the gonadotropic axis at puberty. We aimed to determine whether serum kisspeptin may function as a marker for CPP by investigating serum kisspeptin levels in Korean girls with CPP and their prepubertal controls. Serum kisspeptin levels of Korean girls with CPP (n = 30) and age-matched healthy prepubertal controls (n = 30) were measured with a competitive enzyme immunoassay. Serum kisspeptin levels were significantly higher in CPP group than in control group (4.61 ± 1.78 vs 2.15 ± 1.52 pM/L, P < 0.001). Serum kisspeptin was positively correlated with peak luteinizing hormone (LH), peak/basal LH ratio and peak LH/follicular-stimulating hormone (FSH) ratio during GnRH stimulation test. CPP is supposed to be triggered by premature increase of kisspeptin. Serum kisspeptin may be used as a marker of CPP. Further studies on KISS1 gene polymorphisms leading to higher risk of premature increase of kisspeptin and upstream regulator of kisspeptin are also needed.