PLOD1 and polycystic ovary syndrome: Other endocrine features found in PCOS women are hyperleptinemia, reduced adiponectin, decreased opioidergic tone, and excessive activity of kisspeptin-secreting neurons, thus inducing an increase of Gonadotropin Releasing Hormone (GnRH) and LH release, which is pathognomonic of the syndrome [18,19,20].