Activity of isoflavone in managing polycystic ovary syndrome symptoms (Review)

Abstract

Polycystic ovary syndrome (PCOS), a hormonal and metabolic disorder manifested in women of reproductive age, is still being treated using drugs with side effects. As an alternative to these drugs, isoflavone, also identified as phytoestrogen, has anti-PCOS activity. Isoflavone can help relieve PCOS symptoms by lowering the level of testosterone, which causes hyperandrogenism, thereby normalizing the menstrual cycle and restoring normal ovarian morphology. Furthermore, isoflavone influences the improvement of the metabolic profile, which changes because of PCOS, as well as the reduction of inflammatory markers and oxidative stress. However, both significant and non-significant results have been generated on the activity of isoflavones in PCOS. The present review aims to discuss the existing literature on the effect of isoflavone on PCOS symptoms based on in vivo and clinical trial studies.

Keywords: hyperandrogenism; isoflavone; menstrual cycle; ovarian morphology; polycystic ovary syndrome.

Figure 1

Pathophysiology of PCOS symptoms. Hyperandrogenism, a condition derived from both increasing the androgen level and lowering the sex hormone-binding globulin, is the main cause of other PCOS symptoms, including polycystic ovary morphology and irregular menstruation. The lowering of sex hormone-binding globulin is caused by hyperinsulinemia. Meanwhile, the increase in androgen levels is caused by the production of androgen in both the ovary and adrenal gland as a result of decreasing the activity of aromatase, which decreases the biosynthesis of oestradiol from testosterone. PCOS, polycystic ovary syndrome. The different colours in the testosterone structure refer to the OH bond (green), H bond (orange) and O bond (yellow). The structure at the right bottom refers to the process of converting testosterone to oestradiol by an aromatase catalyst. Steroids are composed of four fused rings (labelled A-D). Aromatase converts the ring labeled ‘A’ into an aromatic state.