Seminal Plasma Biochemical Components Mediate the Inverse Association of Microcystin Exposure with Sperm Motility: A Mediation Analysis in Chinese Men

Epidemiological studies suggest a global decline in male fertility, which accounts for approximately 50％ of infertility cases in couples. Male infertility is a multifactorial and complex issue that may arise due to congenital, acquired, idiopathic, or other unknown factors[1]. Microcystins (MCs), a group of cyanobacterial toxins, have been positively detected in the serum samples of fishermen at Chaohu Lake (0.045–1.832 μg/L)[2] and Taihu Lake (0.1–0.64 μg/L)[3]. To date, MCs have been confirmed to trigger reproductive toxicity, according to a review by Zhang et al.[4]. Furthermore, an epidemiological investigation indicated that exposure to MC is associated with decreased semen quality, particularly reduced sperm motility[5]. However, the specific mechanisms responsible for the negative effects of MCs on sperm motility in both human and animal models are currently unknown.