The therapeutic effect and metabolic mechanism analysis of Guilingji on idiopathic oligo-asthenoteratozoospermia

Introduction: Guilingji, a famous traditional Chinese medicine (TCM) formula, has been used to combat aging and male sexual dysfunction in China for centuries. To date, there has been little evidence-based clinical research on the use of Guilingji to treat idiopathic oligo-asthenoteratozoospermia (OAT), and the therapeutic mechanism from a metabolic perspective needs to be investigated further. Methods: This was a multicenter, double-blind, randomized controlled clinical study of 240 patients with idiopathic OAT recruited from four hospitals between January 2020 and January 2022. Patients were randomly assigned in a 1꞉1 ratio to receive oral Guilingji capsules or placebo for 12 weeks. The total progressive motile sperm count (TPMSC) was considered the primary outcome, and the other sperm parameters, seminal plasma parameters and serum hormones were considered the secondary outcome. A nontargeted metabolomics analysis of serum from OAT patients before and after Guilingji administration was performed by HPLC–MS to identify key metabolites. Furthermore, we used a rat model to show spermatogenesis phenotypes to validate the effect of the key metabolites screened from the patients. Results: At weeks 4, 8 and 12, TPMSC and other sperm parameters were significantly improved in the Guilingji group compared with the placebo group (P