These SCFAs bind to their receptors on enteroendocrine cell membranes and directly stimulate the release of gut-brain mediators such as ghrelin and PYY, whose increase is able to influence sex hormone secretion by the hypophysis and hypothalamus through the gut-brain axis, thus exerting an impact on PCOS symptoms [56]. The gene discussed is PYY; the disease is polycystic ovary syndrome.