The Effect of Phoenix dactylifera pollen on the expression of NRF2, SOD2, CAT, and GPX4 genes, and sperm parameters of fertile and infertile men: A controlled clinical trial

Oxidative stress is caused by the imbalance occurring between the creation and clearance of the reactive oxygen species (ROS), which is responsible for 30-40% of male infertility. The positive impact of phoenix dactylifera pollen (Date palm pollen, DPP) on the improvement of sperm parameters has been well documented in animal models.

For evaluating the effect(s) of DPP on sperm parameters, ROS levels, expression of antioxidant genes, and activity of antioxidant enzymes of infertile men.

In this controlled clinical trial, a total of 60 male case with infertility and 20 normospermic fertile men were recruited. Before and after the treatment with DPP, the case were administered 400 mg/kg of gelatinous capsules daily for 30 consecutive days and semen samples were taken. Quantitative real-time polymerase chain reaction was applied for the evaluation of the mRNA expression levels of Nuclear factor erythroid 2-related factor 2 (NRF2), superoxide dismutase (SOD2), glutathione peroxidase 4 (GPX4), and catalase (CAT) genes.

The mRNA expression levels of NRF2, SOD2, GPX4, and CAT (p < 0.05 for all) and significantly increased after treatment with DPP. The increased expressions of all antioxidant genes and enzymes significantly correlated with improvement in semen parameters including count (p = 0.01), motility (p = 0.05), and morphology (p = 0.01) of sperm. A significant correlation between the alteration of SOD2 gene expression and SOD activity, GPX4 and GPX, and CAT were also observed (p = 0.05).

DPP can increase the expressions of NRF2, GPX4, SOD2, and CAT genes and also improve the semen quality in infertile men.