Can nanomedicine improve the semen quality? The potentials of liposomal curcumin.

Abstract

INTRODUCTION: Worldwide, 10-15 % couples are infertile, and 50 % of the couples seeking assisted reproductive techniques do so because of defective sperm quality. The semen quality can be directly linked to oxidative stress (OS). Due to high metabolic rates and weak anti-oxidant systems, sperm cells are unable to defend against OS produced exogenously and endogenously. Vitamin C and/or vitamin E are anti-oxidants showing promising outcome to reduce OS, but the clinical application has not been fully achieved. Curcumin is an extremely potent lipid-soluble anti-oxidant showing potential in therapy for different human disorders, but its poor bioavailability has limited its wider use. Nanotechnology has been used for the purpose of improving the bioavailability of curcumin. It would be interesting to apply nanotechnology based liposomal delivery of curcumin, a noted anti-oxidant for the enhancement of motility and viability of human sperm cells in vitro. OBJECTIVES: With this study, the aim was to prove anti-oxidative activities of curcumin. We also studied if liposomal formulation of curcumin could maximize the anti-oxidative activities and hopefully enhance motility and viability of sperm cells in vitro. METHODS: Curcumin loaded liposomes were made by the film method followed by extrusion. Anti-oxidative activities of free curcumin were tested with ABTS and DPPH assay methods and compared with vitamin C and vitamin E. The effect of empty liposomes, liposomal curcumin, free curcumin, vitamin C and vitamin E was determined by observing the motility and viability of sperm cells in vitro. RESULTS: Liposomes with curcumin had an average size of 147.82 ±17.3 nm and entrapment efficiency of 88.84 ± 2.3 %. The EC50 for curcumin was 5.82 µM in ABTS and EC50 9.13 µM in DPPH assay, respectively. Anti-oxidants such as curcumin, vitamin C and vitamin E maintained the motility and viability up to 24 hours, however lipid showed toxicity to sperm cells at 0.5 µg/ml or higher concentrations. CONCLUSION: The liposomes containing curcumin were uniformly distributed with high entrapment efficiency. We confirmed anti-oxidative activity of curcumin, however, rather unexpectedly that the liposomal lipid has shown negative effect on sperm viability at certain concentrations. Further studies with more replicates are needed to confirm these findings.

Key words: curcumin, liposomes, anti-oxidant, sperm, motility, viability