In vitro red palm oil (RPO) administration to human spermatozoa: finding a suitable solvent

Abstract

Red palm oil (RPO) has been extensively researched for its antioxidant properties, anti-cancer activities and cardiovascular protective effects. In order to test RPO as a possible in vitro scavenger of reactive oxygen species (ROS) in human sperm a suitable solvent has to be found to introduce RPO to the sperm media because of its hydrophobic nature. In this study we tried to find the best solvent for RPO with the least detrimental effects on sperm motility. RPO was dissolved in different concentrations of solvents: ethanol (75%), dimethylsulphonate [DMSO] (87.5%) and propanol glycol [PGly] (50%) to determine the ease of solubility. These solvents were also added alone to post swim-up normozoospermic samples respectively and their effect on motility was investigated. The most suitable solvent was selected and tested in combination with RPO to determine the combined effects on motility. Motility analysis was performed by computer aided sperm analysis (CASA). It was found that of the 3 solvents tested, PGly (also known as polyethylene glycol) was able to dissolve RPO at much lower concentrations than the other two solvents. Furthermore, PGly has shown to have the least detrimental effects on sperm motility. When RPO was administered in combination with PGly it was able to attenuate the harmful effects that higher dosages of PGly have on sperm motility.