Integrative computational dissection of monobenzyl phthalate spermatotoxicity: High-affinity binding disrupts...

Phthalates, as typical environmental endocrine disruptors, can lead to reproductive toxicity by disrupting human endocrine homeostasis with their metabolites. However, the complexity of human co-exposure to multiple metabolites, confounding biases in traditional studies, and reverse causality issues obscure the causative contributions and pathogenic mechanisms of key toxic metabolites. This study employs a multi-omics integrative strategy, leveraging Mendelian Randomization (MR) to identify Monobenzyl phthalate (MBzP) as a causative risk factor for testicular damage (β = 1.26, P = 0.002). Focusing on Non-obstructive azoospermia (NOA), we integrated network toxicology to identify 15 shared molecular targets. By combining interpretable machine learning, we discovered that core targets ACE2/CYP17A1 are significantly overexpressed in Sertoli cells. Gene Set Enrichment Analysis (GSEA) of single genes revealed critical pathway differentiation: low expression states activate spermatogenesis pathways, while high expression drives inflammatory-apoptotic networks (TGF-β, p53 pathways, interferon response). Molecular docking and dynamics simulation (MDS) confirmed that MBzP forms stable complexes with ACE2 (binding energy = -7.2 kcal/mol) and CYP17A1 (binding energy = -7.5 kcal/mol), interfering with their physiological functions through allosteric effects. This study for the first time elucidates the MBzP-ACE2/CYP17A1 interaction-inflammatory/apoptotic cascade activation-spermatogenesis inhibition molecular axis, providing new targets for precise intervention in male infertility.