Astaxanthin as a potential therapeutic agent in polycystic ovary syndrome: a review of its antioxidant, anti-inflammatory, and metabolic mechanisms.

Polycystic ovary syndrome (PCOS) is the most common heterogeneous disorder among women of reproductive age, characterized by hyperandrogenism, ovulatory dysfunction, and polycystic ovarian morphological changes as its core clinical features. This disease severely affects women's reproductive health and significantly increases the risk of metabolic complications. The pathogenesis of PCOS is complex, involving various pathophysiological mechanisms such as oxidative stress, chronic low-grade inflammation, and insulin resistance. Currently, lifestyle interventions and first-line pharmacological treatments are the primary clinical strategies for managing PCOS. However, existing approaches face numerous limitations in terms of efficacy, safety, and patient compliance, including incomplete therapeutic effects, drug-related side effects, poor adherence, and a lack of long-term safety data, which necessitate further optimization and breakthroughs. Natural compounds have been widely utilized as therapeutic agents worldwide, with some showing potential advantages in preclinical and pharmacological studies, positioning them as potential alternatives to modern drugs. In recent years, astaxanthin, a natural compound, has garnered attention for its auxiliary effects in the treatment of PCOS due to its potent antioxidant and anti-inflammatory properties. Astaxanthin, a strong natural antioxidant derived from Haematococcus pluvialis, exhibits significant antioxidant, anti-inflammatory, anti-proliferative, and anti-apoptotic activities. To systematically evaluate the therapeutic potential of astaxanthin for PCOS, this study conducted a systematic review in strict accordance with the PICOS principles. A comprehensive literature search was performed across PubMed, Web of Science, and Scopus for relevant studies published between January 2020 and March 2026. The retrieved records were screened based on predefined inclusion and exclusion criteria, and the finally included studies were subjected to mechanistic analysis. This review provides a comprehensive analysis of the potential mechanisms by which astaxanthin, as a dietary supplement, improves PCOS through various pathways, including enhancing insulin sensitivity, activating the Nrf2 antioxidant pathway, inhibiting the NF-κB inflammatory signaling pathway, and modulating cellular apoptosis. Furthermore, it delineates the limitations and therapeutic prospects of astaxanthin supplementation, clarifying its significant value in the adjuvant treatment of PCOS and highlighting the key issues that warrant further investigation.