Formulation and evaluation of solid lipid nanoparticles loaded with papaya seed chloroform extract for long-term antifertility effects on the male rat, .

The study is the first to formulate and investigate potential of papaya seed chloroform extract based solid lipid nanoparticles (PSCEN) as antifertility agents on male The prepared nanoparticles were spherical of size 300-600 nm. The release kinetics showed a controlled release of the drug with major release over 48 h. To assess the antifertility effects of PSCEN, adult male rats were fed a diet containing two different concentrations of PSCEN (5% and 10%) for 15 days under bi-choice conditions. The mean total active ingredient ingestion of the rats in the two treated groups ranged from 2.13-3.31 and 3.92-5.87 g/100g body weight, respectively. No adverse effects of treatment on body weight were observed. Also, no mortality of rats was observed. The treatment had a significant effect on the weight of the testis and the epididymis, but not on the other organs. Sperm motility (%), sperm viability (%), sperm count (millions/ml), sperm mitochondrial activity (%), sperm nuclear chromatin de-condensation (%) and sperm hypo-osmotic swelling (%) were significantly decreased, and sperm abnormality (%) significantly increased compared to the vehicle control group. The reproductive success rates of male rats treated with 5% and 10% PSCEN and mated with untreated female rats were 20.00-66.67% and 16.67%, respectively, while in untreated female rats mated with male rats of vehicle control group, reproductive success rate was 33.33 to 80%. The study found a maximal antifertility effect of the 10% PSCEN containing bait, which was irreversible up to 105 days after stopping treatment, suggesting long-term efficacy.