Ameliorating effect of olive oil on fertility of male rats fed on genetically modified soya bean

Background: Genetically modified soya bean (GMSB) is a commercialized food. It has been shown to have adverse effects on fertility in animal trials. Extra virgin olive oil (EVOO) has many beneficial effects including anti-oxidant properties. The aim of this study is to elucidate if addition of EVOO ameliorates the adverse effects on reproductive organs of rats fed on GMSB containing diet. Methods: Forty adult male albino rats (150-180 g) of Sprague Dawley strain were separated into four groups of 10 rats each: Group 1 - control group fed on basal ration, Group 2 - fed on basal ration mixed with EVOO (30%), Group 3 - fed on basal ration mixed with GMSB (15%), and Group 4 - fed on basal ration mixed with GMSB (15%) and EVOO (30%). This feeding regimen was administered for 65 days. Blood samples were collected to analyze serum zinc, vitamin E, and testosterone levels. Histopathological and weight changes in sex organs were evaluated. Results: GMSB diet reduced weight of testis (0.669 +/- 0.06 vs. 1.7 +/- 90.06, p<0.001), epididymis (0.4899 +/- 0.03 vs. 0.79 +/- 0.03, p<0.001), prostate (0.04 +/- 90.009 vs. 0.689 +/- 0.04, p<0.001), and seminal vesicles (0.0579 +/- 0.01 vs. 0.8 +/- 0.04, p<0.001). GMSB diet adversely affected sperm count (406 +/- 7.1 vs. 610 +/- 7.8, p<0.001), motility (p<0.001), and abnormality (p<0.001). GMSB diet also reduced serum zinc (p<0.05), vitamin E (p<0.05), and testosterone (p<0.05) concentrations. EVOO diet had no detrimental effect. Addition of EVOO to GMSB diet increased the serum zinc (pB0.05), vitamin E (pB0.05), and testosterone (pB0.05) levels and also restored the weights of testis (1.35 +/- 0.16 vs. 0.66 +/- 0.06, p<0.01), epididymis (0.614 +/- 0.13 vs. 0.489 +/- 0.03, p<0.001), prostate (0.291 +/- 0.09 vs. 0.04 +/- 0.009, p<0.001), seminal vesicle (0.516 +/- 0.18 vs. 0.057 +/- 0.01, p<0.001) along with sperm count (516 +/- 3.1 vs. 406 +/- 7.1, p<0.01), motility (p<0.01), and abnormality (p<0.05). Conclusion: EVOO ameliorates the adverse effects of GMSB on reproductive organs in adult male albino rats. This protective action of EVOO justifies its use against the oxidative damage induced by GMSB in reproductive organs.