Purpose Semen manipulation for assisted reproductive technology (ART) causes spermatozoa damage; thus, we investigated the potential of the novel therapeutic BGP-15 to preserve sperm quality during semen washing prior to insemination. Methods Donated human ejaculates (N = 40), with or without 10 mu M BGP-15, were analyzed for sperm motility, DNA fragmentation, and oxidation. Seminal plasma was removed using different clinical sperm selection methods: simple wash, swim-up, or density gradient centrifugation (DGC), followed by assessment for sperm motility, mitochondrial ROS (mtROS), mitochondrial membrane potential (MMP), and DNA fragmentation and oxidation. Results Donated semen samples incubated with BGP-15 had increased sperm motility (+ 15%, p = 0.002) and reduced oxidative DNA damage levels (- 57%, p = 0.03). Samples processed by simple wash had the highest sperm count compared with DGC (+ 55%, p < 0.005) and swim-up (+ 21%, p < 0.0005). Swim-up showed increased vitality compared with DGC (+ 18%, p < 0.001) and simple wash (+ 27%, p < 0.0001), as well as the lowest DNA oxidation levels compared with simple wash - 40%, (p = 0.01) and DGC (- 76%, p < 0.0001). Swim-up also had the lowest mitochondrial membrane potential compared with simple wash and DGC (- 28%, p < 0.03). Comparison between untreated and BGP-15-treated groups for each sperm washing method showed that BGP-15 increased MMP in DGC sperm (+ 11%, p = 0.0006), and reduced DNA fragmentation in washed samples (- 22%, p = 0.03). Moreover, BGP-15 lowered DNA oxidation in all preparation methods: washed (- 48%, p = 0.002), swim-up (- 42%, p = 0.04), and DGC (- 29%, p < 0.0001). Conclusions The inclusion of BGP-15 during semen preparation can protect sperm quality and, in the future, may be used clinically to improve sperm selection methods.
