Up-regulation of heme oxygenase-1 expression modulates reactive oxygen species level during the cryopreservation of human seminiferous tubules

Abstract

To study the effect of freezing techniques and to optimize a method for trace amounts of testicular spermatozoa from biopsed seminiferous tubules. The level of reactive oxygen species (ROS) and the gene expression of heme oxygenase-1 was evaluated. Prospective experimental study. University-based laboratory. Eighteen adults with male fator infertility underwent testicular biopsy surgery. Seminiferous tubular fragments from each man were evenly allocated to three groups: fresh control, slow freezing, and vitrifiaction groups. The morphology and ROS levels before and after freezing were evaluated for seminiferous tubular fragments. The expression of heme oxygenase-1 (HO-1) at both the transcriptional and protein levels was determined. The morphology was analyzed by light microscopy. The ROS levels were measured with ELISA. The proliferation and differentiation were evaluated by immunohistochemistry, and the expression of HO-1 was evaluated using a real-time polymerase chain reaction (PCR) and Western blotting. Decreased ROS levels and increased HO-1 expression at the transcriptional and protein levels were observed after thawing the human seminiferous tubules. The ROS level was negatively correlated with HO-1 expression. Slow freezing was more effective than vitrification in terms of HO-1 up-regulation and ROS alteration. Based on our study, the slow freezing technique was more effective compared with the vitrification method.