INTRODUCTIONThe clinical study aimed to evaluate the levels of serum kisspeptin, NKB, and GABA in Chinese patients with polycystic ovary syndrome (PCOS) and explore their association with hormonal profiles, as well as the relationship between these levels in PCOS patients and controls.METHODSFrom December 2022 to December 2023, medical records of 60 individuals diagnosed with PCOS and 32 healthy subjects were obtained. Serum kisspeptin, NKB and GABA levels were quantified using enzyme-linked immunosorbent assay (ELISA) kits. To assess the correlation, either Pearson's or Spearman's analytical method was employed between serum kisspeptin, NKB, and GABA levels and hormonal profiles.RESULTSThe results showed that serum kisspeptin and NKB levels were significantly lower in PCOS patients (p﹤.05), while GABA levels were elevated compared to those in the control group (p﹤.05). In PCOS patients, kisspeptin was notably positive-correlated with LH and LH/FSH (p﹤.05), but no significant correlation was found between NKB, GABA, and hormonal profiles. In PCOS, GABA levels had a strong positive correlation with NKB levels (r = 0.613, p = .000), but this was not observed in the control group. In control patients, kisspeptin levels were positively associated with NKB (r = 0.475, p = .011), strongly negatively correlated with GABA levels (r = -0.773, p = .000), but these were not observed in the PCOS group.CONCLUSIONThe study concluded that patients with PCOS have dysregulated levels of serum kisspeptin, NKB, and GABA and that they may have paradoxical effects under physiological and pathological situations.