Research Information System
BMC Endocrine Disorders, vol.26, no.1, 2026 (SCI-Expanded, Scopus)
Background: Spexin has an inhibitory effect on the hypothalamus (GnRH expression), pituitary (LH and FSH expression) and ovary (estradiol expression). However, Phoenixin potentiate GnRH-stimulated GnRH receptor expression. Our aim is to assess the role of these two functionally opposite peptides in girls with Central Precocious Puberty (CPP). Methods: This prospective study was conducted on three groups of patients (CPP: 33 patients, premature thelarche (PT): 57 patients, and healthy controls: 53 patients). The patients’ anthropometric measurements, pubertal stage, bone age, basal FSH, LH, and estradiol, and peak FSH and LH values obtained from the LH-RH stimulation test were evaluated. The primary aim was to compare Spexin and Phoenixin-20 measurements between groups. Results: Median (Q1–Q3) Spexin levels were 502 pg/mL (314–1434) in the CPP group, 530 pg/mL (234–820) in the PT group, and 626 pg/mL (379–1298) in the control group, with no statistically significant difference between groups (p = 0.177). Median (Q1–Q3) Phoenixin-20 levels were 264 ng/L (206–383) in the CPP group, 252 ng/L (177–383) in the PT group, and 199 ng/L (139–273) in the control group. A statistically significant difference was observed between groups (p = 0.009). Nevertheless, statistical significance between the Phoenixin-20 level of the CPP group and the PT group disappeared after post-hoc analysis. Although Spexin levels tended to be lower and Phoenixin-20 levels higher in the CPP group compared to PT and control groups, the difference was not statistically significant. Correlation analysis demonstrated a weak positive correlation between Phoenixin-20 levels and Tanner stage (r = 0.190, p = 0.023). Conclusions: Although patients with CPP had a lower Spexin and higher Phoenixin-20 level compared to PT and controls, their diagnostic performance was found poor in distinguishing the CPP from PT and healthy controls. Therefore, measurement of these peptides did not find as a diagnostic tool for the diagnosis of CPP and its differentiation from PT. Trial registration number: This study was retrospectively registered at ClinicalTrials.gov (NCT07359092). Unique Protocol ID: SPX-PNX-CPP-2024, Last Update: 01/14/2026