Seminal molecular markers as a non-invasive diagnostic tool for the evaluation of spermatogenesis in non-obstructive azoospermia

Abstract

Non-obstructive azoospermia (NOA) is currently evaluated by the use of conventional histopathological methods. In some cases, focal spermatogenesis is present in the testes of patients with NOA which may be almost undetectable by routine histopathological examinations. Application of molecular markers in semen to predict the spermatogenesis status in the testis will emphasize the probability of finding sperm in NOA testis through further search using TESE or mTESE. Detection of germ cell-specific transcripts in semen is a signal of germ cells present in the testis. In this study, we used molecular methods to evaluate spermatogenesis status in azoospermic men. Semen samples were collected from 203 men with azoospermia. Total RNA was extracted from the semen precipitates. First-strand complementary deoxyribonucleic acid (cDNA) was synthesized by reverse transcriptase then, (RT)-PCRs were carried out using primers for testis stage-specific genes (DAZ, AKAP4, PRM1, and PRM2). Testicular tissue biopsies were used for evaluating spermatogenesis status in testis. Histopathological examination and LH, FSH, and testosterone level measurements (chemiluminescence assay) were performed. The presence of DAZ and PRM2 transcripts in semen significantly indicated the presence of spermatogonia and spermatids in the testicular tissues. Absence of all four markers in semen confirmed the histopathological results corresponding to sertoli cell only syndrome (SCO). Although TESE should not be excluded solely on this criteria, using PRM1, PRM2, AKAP4, and DAZ transcripts in semen would provide a non-invasive molecular diagnostic tool to better counsel patients before undergoing TESE.

Keywords:

• azoospermia
• germ cells
• molecular markers
• semen
• spermatogenesis
• testicular biopsy

Acknowledgments

The authors would like to thank Dr. Hojjat Zeraati (Ph.D.) for his assistance in the statistical analysis of the paper. They are also grateful to Dr. S. Behnam Hashemi (M.D., M.P.H.) for editing the manuscript.

Declaration of Interest: This study was financially supported by grant No. 1424-33 from the Academic Center for Education, Culture and Research (ACECR). The authors had no conflict of interest in doing the research.There are no conflicts of interest.