What is Polycystic Ovary Syndrome (PCOS)?

Polycystic ovary syndrome (PCOS) is a common hormonal disorder that affects people with ovaries, typically during their reproductive years. It is characterized by a combination of symptoms related to hormonal imbalances, menstrual irregularities, and ovarian cysts. PCOS can manifest differently from person to person, and its exact cause is not fully understood, but genetics and hormonal imbalances are believed to play significant roles in its development.


The key features of PCOS include:


  • Menstrual Irregularities: Women with PCOS often experience irregular menstrual cycles, which may manifest as infrequent periods, prolonged periods, or no periods at all (amenorrhea). This irregularity is caused by disruptions in the normal hormonal signals that regulate ovulation.


  • Hyperandrogenism: PCOS is associated with elevated levels of androgens, which are male hormones such as testosterone. This can lead to symptoms of hyperandrogenism, including excess facial or body hair (hirsutism), acne, and male-pattern baldness (androgenic alopecia).


  • Ovarian Cysts: While the term “polycystic” implies the presence of multiple cysts on the ovaries, not all individuals with PCOS develop ovarian cysts. The cysts are typically small, fluid-filled sacs that form on the surface of the ovaries. These cysts are follicles that have not matured properly due to disrupted ovulation.


  • Metabolic Abnormalities: PCOS is often associated with metabolic abnormalities, including insulin resistance, which can lead to elevated blood sugar levels and an increased risk of developing type 2 diabetes. Insulin resistance can also contribute to weight gain and difficulty losing weight, which are common features of PCOS.


  • Fertility Issues: Irregular ovulation and hormonal imbalances associated with PCOS can affect fertility and make it challenging for some individuals to conceive. PCOS is one of the leading causes of infertility in people assigned female at birth.


The exact cause of PCOS is not known, but it is believed to involve a combination of genetic, hormonal, and environmental factors. Insulin resistance and elevated levels of insulin are thought to play a central role in the development of PCOS, as insulin can stimulate the ovaries to produce androgens, disrupt ovulation, and contribute to other metabolic abnormalities associated with the condition.


What is the relationship between PCOS and oxidative stress?

The relationship between polycystic ovary syndrome (PCOS) and oxidative stress is an area of active research, and while the exact mechanisms are not fully understood, several studies have suggested a link between the two.


  • Mitochondrial Dysfunction: Oxidative stress can lead to dysfunction of mitochondria, which are the energy-producing organelles within cells. Some studies have shown that women with PCOS may have impaired mitochondrial function and increased oxidative stress in their ovarian tissues. This dysfunction may contribute to the pathogenesis of PCOS by affecting ovarian function, follicle development, and steroidogenesis (the production of hormones such as estrogen and progesterone).


  • Inflammation: Oxidative stress can trigger inflammatory responses in the body, and chronic low-grade inflammation is believed to be involved in the development of PCOS. Women with PCOS often have elevated levels of inflammatory markers in their blood and ovarian tissues. Inflammatory processes may contribute to insulin resistance, ovarian dysfunction, and other features of PCOS. Additionally, oxidative stress and inflammation can create a vicious cycle, as inflammation can further increase oxidative stress and vice versa.


  • Endothelial Dysfunction: Endothelial dysfunction, which refers to impaired function of the cells lining blood vessels, is associated with oxidative stress and inflammation. Women with PCOS have been found to have abnormalities in endothelial function, which may contribute to cardiovascular complications associated with the syndrome, such as increased risk of cardiovascular disease and hypertension.


  • Antioxidant Defenses: Studies have shown that women with PCOS may have alterations in their antioxidant defense mechanisms, leading to reduced capacity to neutralize reactive oxygen species (ROS) and protect against oxidative damage. This imbalance between ROS production and antioxidant defenses can result in oxidative stress and contribute to the pathogenesis of PCOS.


  • Metabolic Abnormalities: Oxidative stress has been implicated in the metabolic abnormalities commonly observed in PCOS, such as insulin resistance, dyslipidemia (abnormal lipid levels), and obesity. These metabolic disturbances can further exacerbate oxidative stress and contribute to the development and progression of PCOS.


Overall, while the precise role of oxidative stress in the pathogenesis of PCOS is still being elucidated, evidence suggests that oxidative stress may contribute to the development and progression of the syndrome by affecting ovarian function, promoting inflammation, disrupting metabolic homeostasis, and impairing vascular function.