Decreased expression of DNA methyltransferases in the testes of patients with non-obstructive azoospermia leads to changes in global DNA methylation levels
Fatma Uysal A B , Gokhan Akkoyunlu A and Saffet Ozturk A CA Department of Histology and Embryology, Akdeniz University School of Medicine, Campus, 07070, Antalya, Turkey.
B Department of Histology and Embryology, Ankara University School of Medicine, 06100, Ankara, Turkey.
C Corresponding author. Email: sozturk@akdeniz.edu.tr
Reproduction, Fertility and Development 31(8) 1386-1394 https://doi.org/10.1071/RD18246
Submitted: 27 June 2018 Accepted: 13 February 2019 Published: 29 April 2019
Abstract
DNA methylation plays key roles in epigenetic regulation during mammalian spermatogenesis. DNA methyltransferases (DNMTs) function in de novo and maintenance methylation processes by adding a methyl group to the fifth carbon atom of the cytosine residues within cytosine–phosphate–guanine (CpG) and non-CpG dinucleotide sites. Azoospermia is one of the main causes of male infertility, and is classified as obstructive (OA) or non-obstructive (NOA) azoospermia based on histopathological characteristics. The molecular background of NOA is still largely unknown. DNA methylation performed by DNMTs is implicated in the transcriptional regulation of spermatogenesis-related genes. The aim of the present study was to evaluate the cellular localisation and expression levels of the DNMT1, DNMT3A and DNMT3B proteins, as well as global DNA methylation profiles in testicular biopsy samples obtained from men with various types of NOA, including hypospermatogenesis (hyposperm), round spermatid (RS) arrest, spermatocyte (SC) arrest and Sertoli cell-only (SCO) syndrome. In the testicular biopsy samples, DNMT1 expression and global DNA methylation levels decreased gradually from the hyposperm to SCO groups (P < 0.05). DNMT3A expression was significantly decreased in the RS arrest, SC arrest and SCO groups compared with the hyposperm group (P < 0.05). DNMT3B expression was significantly lower in the RS arrest and SCO groups than in the hyposperm group (P < 0.05). Although both DNMT1 and DNMT3A were localised in the cytoplasm and nucleus of the spermatogenic cells, staining for DNMT3B was more intensive in the nucleus of spermatogenic cells. In conclusion, the findings suggest that significant changes in DNMT expression and global DNA methylation levels in spermatogenic cells may contribute to development of male infertility in the NOA groups. Further studies are needed to determine the molecular biological effects of the altered DNMT expression and DNA methylation levels on development of male infertility.
Additional keywords: DNMTs, male infertility, spermatogenesis, testis.
References
Adiga, S. K., Ehmcke, J., Schlatt, S., Kliesch, S., Westernstroer, B., Luetjens, C. M., Wistuba, J., and Gromoll, J. (2011). Reduced expression of DNMT3B in the germ cells of patients with bilateral spermatogenic arrest does not lead to changes in the global methylation status. Mol. Hum. Reprod. 17, 545–549.| Reduced expression of DNMT3B in the germ cells of patients with bilateral spermatogenic arrest does not lead to changes in the global methylation status.Crossref | GoogleScholarGoogle Scholar | 21482616PubMed |
Barau, J., Teissandier, A., Zamudio, N., Roy, S., Nalesso, V., Herault, Y., Guillou, F., and Bourc’his, D. (2016). The DNA methyltransferase DNMT3C protects male germ cells from transposon activity. Science 354, 909–912.
| The DNA methyltransferase DNMT3C protects male germ cells from transposon activity.Crossref | GoogleScholarGoogle Scholar | 27856912PubMed |
Boissonnas, C. C., Jouannet, P., and Jammes, H. (2013). Epigenetic disorders and male subfertility. Fertil. Steril. 99, 624–631.
| Epigenetic disorders and male subfertility.Crossref | GoogleScholarGoogle Scholar | 23714437PubMed |
Cooper, T. G., Noonan, E., von Eckardstein, S., Auger, J., Baker, H. W., and Behre, H. M. (2010). World Health Organization reference values for human semen characteristics. Hum. Reprod. Update 16, 231–245.
| World Health Organization reference values for human semen characteristics.Crossref | GoogleScholarGoogle Scholar | 19934213PubMed |
Cui, X., Jing, X., Wu, X., Yan, M., Li, Q., Shen, Y., and Wang, Z. (2016). DNA methylation in spermatogenesis and male infertility. Exp. Ther. Med. 12, 1973–1979.
| DNA methylation in spermatogenesis and male infertility.Crossref | GoogleScholarGoogle Scholar | 27698683PubMed |
Deplus, R., Brenner, C., Burgers, W. A., Putmans, P., Kouzarides, T., de Launoit, Y., and Fuks, F. (2002). Dnmt3L is a transcriptional repressor that recruits histone deacetylase. Nucleic Acids Res. 30, 3831–3838.
| Dnmt3L is a transcriptional repressor that recruits histone deacetylase.Crossref | GoogleScholarGoogle Scholar | 12202768PubMed |
Dubé, E., Hermo, L., Chan, P. T. K., and Cyr, D. G. (2008). Alterations in gene expression in the caput epididymides of nonobstructive azoospermic men. Biol. Reprod. 78, 342–351.
| Alterations in gene expression in the caput epididymides of nonobstructive azoospermic men.Crossref | GoogleScholarGoogle Scholar | 17928628PubMed |
Fatemi, M., Hermann, A., Gowher, H., and Jeltsch, A. (2002). Dnmt3a and Dnmt1 functionally cooperate during de novo methylation of DNA. Eur. J. Biochem. 269, 4981–4984.
| Dnmt3a and Dnmt1 functionally cooperate during de novo methylation of DNA.Crossref | GoogleScholarGoogle Scholar | 12383256PubMed |
Filipponi, D., and Feil, R. (2009). Perturbation of genomic imprinting in oligozoospermia. Epigenetics 4, 27–30.
| Perturbation of genomic imprinting in oligozoospermia.Crossref | GoogleScholarGoogle Scholar | 19106644PubMed |
Fox, M. S., Ares, V. X., Turek, P. J., Haqq, C., and Reijo Pera, R. A. (2003). Feasibility of global gene expression analysis in testicular biopsies from infertile men. Mol. Reprod. Dev. 66, 403–421.
| Feasibility of global gene expression analysis in testicular biopsies from infertile men.Crossref | GoogleScholarGoogle Scholar | 14579417PubMed |
Gnoth, C., Godehardt, E., Frank-Herrmann, P., Friol, K., Tigges, J., and Freundl, G. (2005). Definition and prevalence of subfertility and infertility. Hum. Reprod. 20, 1144–1147.
| Definition and prevalence of subfertility and infertility.Crossref | GoogleScholarGoogle Scholar | 15802321PubMed |
Goll, M. G., Kirpekar, F., Maggert, K. A., Yoder, J. A., Hsieh, C. L., Zhang, X., Golic, K. G., Jacobsen, S. E., and Bestor, T. H. (2006). Methylation of tRNAAsp by the DNA methyltransferase homolog Dnmt2. Science 311, 395–398.
| Methylation of tRNAAsp by the DNA methyltransferase homolog Dnmt2.Crossref | GoogleScholarGoogle Scholar | 16424344PubMed |
Hamada, A., Esteves, S. C., Nizza, M., and Agarwal, A. (2012). Unexplained male infertility: diagnosis and management. Int. Braz J Urol 38, 576–594.
| Unexplained male infertility: diagnosis and management.Crossref | GoogleScholarGoogle Scholar | 23131516PubMed |
Heyn, H., Ferreira, H. J., Bassas, L., Bonache, S., Sayols, S., Sandoval, J., Esteller, M., and Larriba, S. (2012). Epigenetic disruption of the PIWI pathway in human spermatogenic disorders. PLoS One 7, e47892.
| Epigenetic disruption of the PIWI pathway in human spermatogenic disorders.Crossref | GoogleScholarGoogle Scholar | 23112866PubMed |
Jarow, J. P., Espeland, M. A., and Lipshultz, L. I. (1989). Evaluation of the azoospermic patient. J. Urol. 142, 62–65.
| Evaluation of the azoospermic patient.Crossref | GoogleScholarGoogle Scholar | 2499695PubMed |
Kläver, R., Tüttelmann, F., Bleiziffer, A., Haaf, T., Kliesch, S., and Gromoll, J. (2013). DNA methylation in spermatozoa as a prospective marker in andrology. Andrology 1, 731–740.
| DNA methylation in spermatozoa as a prospective marker in andrology.Crossref | GoogleScholarGoogle Scholar | 23970452PubMed |
Lin, Y. H., Lin, Y. M., Teng, Y. N., Hsieh, T. Y., Lin, Y. S., and Kuo, P. L. (2006). Identification of ten novel genes involved in human spermatogenesis by microarray analysis of testicular tissue. Fertil. Steril. 86, 1650–1658.
| Identification of ten novel genes involved in human spermatogenesis by microarray analysis of testicular tissue.Crossref | GoogleScholarGoogle Scholar | 17074343PubMed |
Malcher, A., Rozwadowska, N., Stokowy, T., Kolanowski, T., Jedrzejczak, P., Zietkowiak, W., and Kurpisz, M. (2013). Potential biomarkers of nonobstructive azoospermia identified in microarray gene expression analysis. Fertil. Steril. 100, 1686–1694.e7.
| Potential biomarkers of nonobstructive azoospermia identified in microarray gene expression analysis.Crossref | GoogleScholarGoogle Scholar | 24012201PubMed |
Margot, J. B., Ehrenhofer-Murray, A. E., and Leonhardt, H. (2003). Interactions within the mammalian DNA methyltransferase family. BMC Mol. Biol. 4, 7.
| Interactions within the mammalian DNA methyltransferase family.Crossref | GoogleScholarGoogle Scholar | 12777184PubMed |
Marques, C. J., Costa, P., Vaz, B., Carvalho, F., Fernandes, S., Barros, A., and Sousa, M. (2008). Abnormal methylation of imprinted genes in human sperm is associated with oligozoospermia. Mol. Hum. Reprod. 14, 67–74.
| Abnormal methylation of imprinted genes in human sperm is associated with oligozoospermia.Crossref | GoogleScholarGoogle Scholar | 18178607PubMed |
Marques, C. J., Joao Pinho, M., Carvalho, F., Bieche, I., Barros, A., and Sousa, M. (2011). DNA methylation imprinting marks and DNA methyltransferase expression in human spermatogenic cell stages. Epigenetics 6, 1354–1361.
| DNA methylation imprinting marks and DNA methyltransferase expression in human spermatogenic cell stages.Crossref | GoogleScholarGoogle Scholar | 22048249PubMed |
Mukherjee, M., Ge, G., Zhang, N., Huang, E., Nakamura, L. V., Minor, M., Fofanov, V., Rao, P. H., Herron, A., and Pati, D. (2011). Separase loss of function cooperates with the loss of p53 in the initiation and progression of T- and B-cell lymphoma, leukemia and aneuploidy in mice. PLoS One 6, e22167.
| Separase loss of function cooperates with the loss of p53 in the initiation and progression of T- and B-cell lymphoma, leukemia and aneuploidy in mice.Crossref | GoogleScholarGoogle Scholar | 21799785PubMed |
Ozturk, S., Sozen, B., Uysal, F., Bassorgun, I. C., Usta, M. F., Akkoyunlu, G., and Demir, N. (2016). The poly(A)-binding protein genes, EPAB, PABPC1, and PABPC3 are differentially expressed in infertile men with non-obstructive azoospermia. J. Assist. Reprod. Genet. 33, 335–348.
| The poly(A)-binding protein genes, EPAB, PABPC1, and PABPC3 are differentially expressed in infertile men with non-obstructive azoospermia.Crossref | GoogleScholarGoogle Scholar | 26843391PubMed |
Pacheco, S. E., Houseman, E. A., Christensen, B. C., Marsit, C. J., Kelsey, K. T., Sigman, M., and Boekelheide, K. (2011). Integrative DNA methylation and gene expression analyses identify DNA packaging and epigenetic regulatory genes associated with low motility sperm. PLoS One 6, e20280.
| Integrative DNA methylation and gene expression analyses identify DNA packaging and epigenetic regulatory genes associated with low motility sperm.Crossref | GoogleScholarGoogle Scholar | 21674046PubMed |
Poplinski, A., Tuttelmann, F., Kanber, D., Horsthemke, B., and Gromoll, J. (2010). Idiopathic male infertility is strongly associated with aberrant methylation of MEST and IGF2/H19 ICR1. Int. J. Androl. 33, 642–649.
| 19878521PubMed |
Ramasamy, R., Ridgeway, A., Lipshultz, L. I., and Lamb, D. J. (2014). Integrative DNA methylation and gene expression analysis identifies discoidin domain receptor 1 association with idiopathic nonobstructive azoospermia. Fertil. Steril. 102, 968–973.e3.
| Integrative DNA methylation and gene expression analysis identifies discoidin domain receptor 1 association with idiopathic nonobstructive azoospermia.Crossref | GoogleScholarGoogle Scholar | 25064398PubMed |
Rockett, J. C., Patrizio, P., Schmid, J. E., Hecht, N. B., and Dix, D. J. (2004). Gene expression patterns associated with infertility in humans and rodent models. Mutat. Res. 549, 225–240.
| Gene expression patterns associated with infertility in humans and rodent models.Crossref | GoogleScholarGoogle Scholar | 15120973PubMed |
Saini, S. K., Mangalhara, K. C., Prakasam, G., and Bamezai, R. N. K. (2017). DNA methyltransferase1 (DNMT1) isoform3 methylates mitochondrial genome and modulates its biology. Sci. Rep. 7, 1525.
| DNA methyltransferase1 (DNMT1) isoform3 methylates mitochondrial genome and modulates its biology.Crossref | GoogleScholarGoogle Scholar | 28484249PubMed |
Saitou, M., Kagiwada, S., and Kurimoto, K. (2012). Epigenetic reprogramming in mouse pre-implantation development and primordial germ cells. Development 139, 15–31.
| Epigenetic reprogramming in mouse pre-implantation development and primordial germ cells.Crossref | GoogleScholarGoogle Scholar | 22147951PubMed |
Smallwood, S. A., and Kelsey, G. (2012). De novo DNA methylation: a germ cell perspective. Trends Genet. 28, 33–42.
| De novo DNA methylation: a germ cell perspective.Crossref | GoogleScholarGoogle Scholar | 22019337PubMed |
Turek-Plewa, J., and Jagodzinski, P. P. (2005). The role of mammalian DNA methyltransferases in the regulation of gene expression. Cell. Mol. Biol. Lett. 10, 631–647.
| 16341272PubMed |
Uysal, F., Akkoyunlu, G., and Ozturk, S. (2015). Dynamic expression of DNA methyltransferases (DNMTs) in oocytes and early embryos. Biochimie 116, 103–113.
| Dynamic expression of DNA methyltransferases (DNMTs) in oocytes and early embryos.Crossref | GoogleScholarGoogle Scholar | 26143007PubMed |
Uysal, F., Akkoyunlu, G., and Ozturk, S. (2016). DNA methyltransferases exhibit dynamic expression during spermatogenesis. Reprod. Biomed. Online 33, 690–702.
| DNA methyltransferases exhibit dynamic expression during spermatogenesis.Crossref | GoogleScholarGoogle Scholar | 27687053PubMed |
Wosnitzer, M., Goldstein, M., and Hardy, M. P. (2014). Review of azoospermia. Spermatogenesis 4, e28218.
| Review of azoospermia.Crossref | GoogleScholarGoogle Scholar | 25105055PubMed |