Evaluation of serum levels of excitatory-inhibitory amino acids, leptin and kisspeptins using sleep profile and effects on development of puberty

Aim: Comparison of precocious puberty and premature telarch cases admitted to Celal Bayar University, School of Medicine, Pediatric endocrinology clinic, with healthy, control, children regarding kispeptin, leptin, prolactin, inhibitor aminoacid levels; evaluation of effects of serum kispeptin, leptin, prolactin, and excitatory-inhibitory aminoacids on development of puberty.Method: Between 2009 and 2010, 39 girl patients, admitted to pediatric endocrinology clinic, with early breast development, has been evaluated by physical examinaton, basal FSH, LH, estradiol, radiography of left hand and wrist, and pelvic ultrasonography. LHRH test was performed to patients for differentiation of precocious puberty and premature telarch. Depending on the results of the test 22 patient, as premature telarch, and 17 patients, as precocious puberty, was included in the study. 19 age- matched, pre-pubertal girls, admitted to general pediatric clinic with other complaints, was included in study as control group. Polysomnography was carried out to patients for detection of REM periods and evaluation of effects of sleep on pubertal development. During REM periods venous blood samples were collected and levels of kispeptin, serum kispeptin, leptin, prolactin, GABA and glutamate were assessed.Results: Mean age of control, premature telarch and precocious puberty groups were 8,25 ± 1,06, 6,99 ± 1,14 and 7,93 ± 0,77 years,respectively. There was no difference regarding anthropometric parameters such as height, height SDS, BMI, BMI SDS, BMI percentile, and height-for-weight values between control and patient groups. Basal FSH and LH levels in precocious puberty group were significantly higher compared to other two groups (p=0,006 and p=0,029, respectively ). While basal LH/FSH ratio showed no difference between premature telarch and precocious puberty groups, 30th minute LH/FSH ratio was higher in precocious puberty group which was statistically significant (p<0,001). Bone age/chronologial age ratio, endometrium thickness, and ovarian volumes in precocious puberty group were significantly different compared to other two groups. Evaluation of nocturnal kispeptin, leptin, prolactin, GABA and glutamate levels revealed no statistically signifificant difference between three groups. No significant correlation between anthropometric parameters and leptin and kispeptin levels was determined. First interval of sleep were found to be shorter in permature telarch group compared to precocious puberty and control groups when evaluation of sleep profile for 3 groups was performed (p=0,031).Conclusion: Leptin, kispeptin, GABA, glutamate and prolactin levels ,responsible for pubertal activation, were not different among precocious puberty, premature telarch and pre-pubertal control groups. Bone age, endometrium thickness, ovarian sizes, and 30th minute LH/FSH ratio are the tests that can be used for differential diagnosis of premature telarch and precocious puberty. Sleep profile evaluation of precocious puberty, premature telarch, and pre-pubertal control groups revealed no difference in sleep stages other than first stage.Key words: puberty precocious, premature telache, kisspeptin, leptin, excitator amino acids