scholarly journals Cellular Therapy via Spermatogonial Stem Cells for Treating Impaired Spermatogenesis, Non-Obstructive Azoospermia

Cells ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1779
Author(s):  
Nesma E. Abdelaal ◽  
Bereket Molla Tanga ◽  
Mai Abdelgawad ◽  
Sahar Allam ◽  
Mostafa Fathi ◽  
...  

Male infertility is a major health problem affecting about 8–12% of couples worldwide. Spermatogenesis starts in the early fetus and completes after puberty, passing through different stages. Male infertility can result from primary or congenital, acquired, or idiopathic causes. The absence of sperm in semen, or azoospermia, results from non-obstructive causes (pretesticular and testicular), and post-testicular obstructive causes. Several medications such as antihypertensive drugs, antidepressants, chemotherapy, and radiotherapy could lead to impaired spermatogenesis and lead to a non-obstructive azoospermia. Spermatogonial stem cells (SSCs) are the basis for spermatogenesis and fertility in men. SSCs are characterized by their capacity to maintain the self-renewal process and differentiation into spermatozoa throughout the male reproductive life and transmit genetic information to the next generation. SSCs originate from gonocytes in the postnatal testis, which originate from long-lived primordial germ cells during embryonic development. The treatment of infertility in males has a poor prognosis. However, SSCs are viewed as a promising alternative for the regeneration of the impaired or damaged spermatogenesis. SSC transplantation is a promising technique for male infertility treatment and restoration of spermatogenesis in the case of degenerative diseases such as cancer, radiotherapy, and chemotherapy. The process involves isolation of SSCs and cryopreservation from a testicular biopsy before starting cancer treatment, followed by intra-testicular stem cell transplantation. In general, treatment for male infertility, even with SSC transplantation, still has several obstacles. The efficiency of cryopreservation, exclusion of malignant cells contamination in cancer patients, and socio-cultural attitudes remain major challenges to the wider application of SSCs as alternatives. Furthermore, there are limitations in experience and knowledge regarding cryopreservation of SSCs. However, the level of infrastructure or availability of regulatory approval to process and preserve testicular tissue makes them tangible and accurate therapy options for male infertility caused by non-obstructive azoospermia, though in their infancy, at least to date.

2019 ◽  
Vol 31 (8) ◽  
pp. 1386 ◽  
Author(s):  
Fatma Uysal ◽  
Gokhan Akkoyunlu ◽  
Saffet Ozturk

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.


2012 ◽  
Vol 27 (4) ◽  
pp. 998-1004 ◽  
Author(s):  
I. Gies ◽  
J. De Schepper ◽  
D. Van Saen ◽  
E. Anckaert ◽  
E. Goossens ◽  
...  

2021 ◽  
Author(s):  
Dongdong Tang ◽  
Mingrong Lv ◽  
Yang Gao ◽  
Huiru Cheng ◽  
Kuokuo Li ◽  
...  

Abstract Background Non-obstructive azoospermia (NOA) is the most severe form of male infertility. More than half of the NOA patients were idiopathic for their etiology, in whom it’s difficult to retrieve sperm despite the application of microsurgical testicular sperm extraction (microTESE). Therefore, we conducted to this study to identify the potential genetic factors responsible for NOA, and investigate the sperm retrieval rate of microTESE for the genetic defected NOA.Methods One NOA patient from a consanguineous family (F1-II-1) and fifty NOA patients from non-consanguineous families were included in the study. Semen analyses, chromosome karyotypes, screening of Y chromosome microdeletions, sex hormone testing, and subsequent testicular biopsy were performed to categorize NOA or obstructive azoospermia. Potentialgenetic variants were identified by whole exome sequencing (WES),and confirmed by Sanger sequencing in F1 II-1. The candidate genes were screened in the other fifty NOA patients. Further experiments including quantitative real time-polymerase chain reaction and western blotting were performed to verify the effects of gene variation on gene expression.Results Normal somatic karyotypes and Y chromosome microdeletions were examined in all patients. Hematoxylin and eosin staining (H&E) of the testicular tissues suggested meiotic arrest, and a novel homozygous HFM1 variant (c.3490C>T: p.Q1164X) was identified in F1 II-1. Furthermore, another homozygous HFM1 variant (c.3470G>A: p.C1157Y) was also verified in F2 II-1 from the fifty NOA patients. Significantly decreased expression levels of HFM1 mRNA and protein were observed in the testicular tissues of these two mutants compared with controls. MicroTESE was performed in these two patients, while no sperm were retrieved. Conclusions Our study identified two novel homozygous variants of HFM1 that are responsible for spermatogenic failure and NOA, even microTESE can not contribute to retrieve sperm in these patients.


2021 ◽  
Vol 0 (0) ◽  
pp. 0 ◽  
Author(s):  
Ming-Han Tong ◽  
Jin-Song Li ◽  
Ying-Hua Wang ◽  
Meng Yan ◽  
Xi Zhang ◽  
...  

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Dongdong Tang ◽  
Mingrong Lv ◽  
Yang Gao ◽  
Huiru Cheng ◽  
Kuokuo Li ◽  
...  

Abstract Background Non-obstructive azoospermia (NOA) is the most severe form of male infertility; more than half of the NOA patients are idiopathic. Although many NOA risk genes have been detected, the genetic factors for NOA in majority of the patients are unknown. In addition, it is difficult to retrieve sperm from these patients despite using the microsurgical testicular sperm extraction (microTESE) method. Therefore, we conducted this genetic study to identify the potential genetic factors responsible for NOA and investigate the sperm retrieval rate of microTESE for genetically deficient NOA patients. Methods Semen analyses, sex hormone testing, and testicular biopsy were performed to categorize the patients with NOA. The chromosome karyotypes and Y chromosome microdeletion analyses were used to exclude general genetic factors. Whole exome sequencing and Sanger sequencing were performed to identify potential genetic variants in 51 patients with NOA. Hematoxylin and eosin staining (H&E) and anti-phosphorylated H2AX were used to assess the histopathology of spermatogenesis. Quantitative real time-polymerase chain reaction, western blotting, and immunofluorescence were performed to verify the effects of gene variation on expression. Results We performed whole exome sequencing in 51 NOA patients and identified homozygous helicase for meiosis 1(HFM1) variants (NM_001017975: c.3490C > T: p.Q1164X; c.3470G > A: p.C1157Y) in two patients (3.9%, 2/51). Histopathology of the testis showed that spermatogenesis was completely blocked at metaphase in these two patients carrying the HFM1 homozygous variants. In comparison with unaffected controls, we found a significant reduction in the levels of HFM1 mRNA and protein expression in the testicular tissues from these two patients. The patients were also subjected to microTESE treatment, but the sperms could not be retrieved. Conclusions This study identified novel homozygous variants of HFM1 that are responsible for spermatogenic failure and NOA, and microTESE did not aid in retrieving sperms from these patients.


2013 ◽  
Vol 30 (10) ◽  
pp. 1271-1277 ◽  
Author(s):  
Mohammadreza Gholami ◽  
Masoud Hemadi ◽  
Ghasem Saki ◽  
Abolfazl Zendedel ◽  
Ali Khodadadi ◽  
...  

2009 ◽  
Vol 92 (3) ◽  
pp. S28
Author(s):  
F. Izadyar ◽  
C. Maki ◽  
J. Pacchiarotti ◽  
J. Barritt ◽  
N. Bar-Chama ◽  
...  

2011 ◽  
Vol 95 (7) ◽  
pp. 2399-2403 ◽  
Author(s):  
Sok Siam Gouk ◽  
Yu Feng Jason Loh ◽  
Srinivasan D. Kumar ◽  
Paul F. Watson ◽  
Lilia L. Kuleshova

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