The influence of rosmarinic acid on male reproductive health: Biological mechanisms and clinical prospects.

Male infertility is a condition affecting up to 15% of couples worldwide. It is frequently driven by oxidative stress and inflammation that impair spermatogenesis and hormone regulation. Rosmarinic acid (RA) as a naturally occurring polyphenolic compound has appeared as a potent antioxidant and anti-inflammatory agent with promising reproductive benefits. According to experimental models, RA reduces testicular damage brought on by oxidative stress, restores antioxidant enzyme activity, maintains testosterone and gonadotropin levels, and preserves sperm motility and morphology. These effects are mechanistically mediated through inhibition of inflammatory cytokines, protection of Leydig cell steroidogenesis, modification of NF-κB and Nrf2 pathways, and radical scavenging. There is still a lack of sufficient human data despite substantial preclinical validation, and concerns about bioavailability and standardized dosage call for more research. This review consolidates current evidence on RA's chemistry, pharmacokinetics, and mechanistic actions in the male reproductive system.