Metabolic and Anti-Inflammatory Effects of Berberine—Rationale for Its Therapeutic Potential in Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is a common hormonal disorder in women of reproductive age and is characterized by ovarian hyperandrogenism and irregular ovulation. This often leads to infertility. Beyond reproduction, PCOS causes widespread metabolic issues such as insulin resistance (IR), increasing long-term risks for diabetes, obesity, and heart disease. In a vicious cycle, IR acts as a core driver of both clinical symptoms and associated obesity, whereas compensatory hyperinsulinemia stimulates ovarian androgen production, causing ovulatory dysfunction and worsening weight gain, with immune imbalances exacerbating systemic chronic low-grade inflammation (CLGI). Berberine is a natural plant alkaloid that, owing to its multifaceted metabolic effects—including activation of 5′ adenosine monophosphate (AMP)-activated protein kinase (AMPK) and improvement of insulin sensitivity—effectively supports the restoration of homeostasis in women with PCOS. The aim of this narrative review is to comprehensively analyze the metabolic and anti-inflammatory actions of berberine, which, in combination with the known pathomechanisms of PCOS, may constitute a rationale for its therapeutic application. Attention was given to the necessity of actions aimed at increasing the bioavailability of berberine and to the consequences of the fact that berberine, unlike metformin, which is commonly used and has similar properties, is a dietary supplement and not a Food and Drug Administration (FDA)-approved prescription drug.