RESUMO
Based on studies that focused on the effect of SARS-CoV-2 on human tissues, not only pulmonary invasion was revealed, but also impaired testicular function. Thus, the study of the mechanisms of influence of SARS-CoV-2 on spermatogenesis is still relevant. Of particular interest is the study of pathomorphological changes in men of different age groups. The purpose of this study was to evaluate immunohistochemical changes in spermatogenesis during SARS-CoV-2 invasion in different age groups. In our study, for the first time, a cohort of COVID-19-positive patients of different age groups was collected, and the following were conducted--confocal microscopy of the testicles and immunohistochemical evaluation of spermatogenesis disorders in SARS-CoV-2 invasion with antibodies to the spike protein, the nucleocapsid protein of the SARS-CoV-2 virus, and angiotensin convertase type 2. An IHC study and confocal microscopy of testicular autopsies from COVID-19-positive patients revealed an increase in the number of S-protein- and nucleocapsid-positively stained spermatogenic cells, which indicates SARS-CoV-2 invasion into them. A correlation was found between the number of ACE2-positive germ cells and the degree of hypospermatogenesis, and in the group of patients with confirmed coronavirus infection older than 45 years, the decrease in spermatogenic function was more pronounced than in the cohort of young people. Thus, our study found a decrease in both spermatogenic and endocrine (Leydig cells) testicular functions in patients with COVID-19 infection. In the elderly, these changes were significantly higher than in the group of young patients.
RESUMO
The fructose-streptozotocin (FRU-STZ) diabetic model has been presented as a viable model of type2 diabetes but its impact on the testes and epididymis of Wistar rats is yet to be investigated. In this study, we probed the role of caffeic acid, a potent antioxidant, in FRU-STZ diabetic rats. Twenty normoglycemic rats were randomly divided into four groups of five rats each: Control, Fructose-Streptozotocin (FRU+STZ), Fructose-Streptozotocin + Caffeic Acid (FRU+STZ+CA), and Caffeic Acid (CA). Diabetes was induced by the administration of 10 % fructose solution ad libitum for 2 weeks followed by a single intraperitoneal injection of 50 mg/kg bwt of streptozotocin. Treatment with CA (50 mg/kg bwt) lasted for two weeks. Results showed that FRU-STZ diabetes was able to induce amyloidosis and histopathological deficits in the testis and epididymis characteristic of cytotoxic agents. Poor PCNA immunoreactivity, reactive Nrf2 expression, and defective steroidogenesis were also observed in the diabetic group. FRU-STZ diabetes was also associated with significantly increased Na+-K+ ATPase activity in both testes and epididymis. Treatment with caffeic acid was able to restore steroidogenesis and spermatogenesis in the diabetic rats to levels comparable to the control; histological features and Na+-K+ ATPase activity were also reduced in the CA-treated group. Generally, normal rats treated with caffeic acid did not evince any deleterious effects. Our study demonstrates that CA exerts a protective role in FRU-STZ diabetes.
Assuntos
Amiloidose , Diabetes Mellitus Experimental , Oligospermia , Animais , Masculino , Ratos , Adenosina Trifosfatases , Membrana Celular , Diabetes Mellitus Experimental/tratamento farmacológico , Epididimo , Frutose , Fator 2 Relacionado a NF-E2 , Antígeno Nuclear de Célula em Proliferação , Ratos Wistar , Estreptozocina , TestículoRESUMO
Genetic syndromes that affect the nervous system may also disrupt testicular function, and the mechanisms for these effects may be interrelated. Most often neurological signs and symptoms predominate and hypogonadism remains undetected and untreated, while in other cases, a thorough evaluation of a hypogonadal male reveals previously unrecognized ataxia, movement disorder, muscle weakness, tremor, or seizures, leading to a syndromic diagnosis. Androgen deficiency in patients with neurological diseases may aggravate muscle weakness and fatigue and predispose patients to osteoporosis and obesity. The purpose of this mini review is to provide a current understanding of the clinical, biochemical, histologic, and genetic features of syndromes in which male hypogonadism and neurological dysfunction may coexist and may be encountered by the clinical endocrinologist.
Assuntos
Androgênios , Hipogonadismo , Androgênios/uso terapêutico , Humanos , Hipogonadismo/tratamento farmacológico , Masculino , Debilidade Muscular/tratamento farmacológico , Síndrome , Testosterona/uso terapêuticoRESUMO
Understanding molecular mechanisms that underpin azoospermia and discovery of biomarkers that could enable reliable, non-invasive diagnosis are highly needed. Using label-free data-independent LC-MS/MS acquisition coupled with ion mobility, we compared the FFPE testicular proteome of patients with obstructive (OA) and non-obstructive azoospermia (NOA) subtypes hypospermatogenesis (Hyp) and Sertoli cell-only syndrome (SCO). Out of 2044 proteins identified based on ≥2 peptides, 61 proteins had the power to quantitatively discriminate OA from NOA and 30 to quantitatively discriminate SCO from Hyp and OA. Among these, H1-6, RANBP1 and TKTL2 showed superior potential for quantitative discrimination among OA, Hyp and SCO. Integrin signaling pathway, adherens junction, planar cell polarity/convergent extension pathway and Dectin-1 mediated noncanonical NF-kB signaling were significantly associated with the proteins that could discriminate OA from NOA. Comparison with 2 transcriptome datasets revealed 278 and 55 co-differentially expressed proteins/genes with statistically significant positive correlation. Gene expression analysis by qPCR of 6 genes (H1-6, RANBP1, TKTL2, TKTL1, H2BC1, and ACTL7B) with the highest discriminatory power on protein level and the same regulation trend with transcriptomic datasets, confirmed the proteomics results. In summary, our results suggest some underlying pathways in azoospermia and broaden the range of potential novel candidates for diagnosis. SIGNIFICANCE: Using a comparative proteomics approach on testicular tissue we have identified several pathways associated with azoospermia and a number of testis-specific and germ cell-specific proteins that have the potential to pinpoint the type of spermatogenesis failure. Furthermore, comparison with transcriptomics datasets based on genome-wide gene expression analyses of human testis specimens from azoospermia patients identified proteins that could discriminate between obstructive and non-obstructive azoospermia subtypes on both protein and mRNA levels. Up to our knowledge, this is the first integrated comparative analysis of proteomics and transcriptomics data from testicular tissues. We believe that the data from our study contributes significantly to increase the knowledge of molecular mechanisms of azoospermia and pave the way for new investigations in regards to non-invasive diagnosis.
Assuntos
Azoospermia , Oligospermia , Azoospermia/diagnóstico , Biomarcadores/metabolismo , Cromatografia Líquida , Humanos , Masculino , Oligospermia/genética , Oligospermia/metabolismo , Proteômica , Espectrometria de Massas em Tandem , Testículo/metabolismo , Transcetolase/metabolismoRESUMO
Background: Infertile men with non-obstructive azoospermia (NOA) have impaired spermatogenesis. Dilated and un-dilated atrophic seminiferous tubules are often present in the testes of these patients, with the highest likelihood of active spermatogenesis in the dilated tubules. Little is known about the un-dilated tubules, which in NOA patients constitute the majority. To advance therapeutic strategies for men with NOA who fail surgical sperm retrieval we aimed to characterize the spermatogonial stem cell microenvironment in atrophic un-dilated tubules. Methods: Testis biopsies approximately 3x3x3 mm3 were obtained from un-dilated areas from 34 patients. They were classified as hypospermatogenesis (HS) (n=5), maturation arrest (MA) (n=14), and Sertoli cell only (SCO) (n= 15). Testis samples from five fertile men were included as controls. Biopsies were used for histological analysis, RT-PCR analysis and immunofluorescence of germ and Sertoli cell markers. Results: Anti-Müllerian hormone mRNA and protein expression was increased in un-dilated tubules in all three NOA subtypes, compared to the control, showing an immature state of Sertoli cells (p<0.05). The GDNF mRNA expression was significantly increased in MA (P=0.0003). The BMP4 mRNA expression showed a significant increase in HS, MA, and SCO (P=0.02, P=0.0005, P=0.02, respectively). The thickness of the tubule wall was increased 2.2-fold in the SCO-NOA compared to the control (p<0.05). In germ cells, we found the DEAD-box helicase 4 (DDX4) and melanoma-associated antigen A4 (MAGE-A4) mRNA and protein expression reduced in NOA (MAGE-A: 46% decrease in HS, 53% decrease in MA, absent in SCO). In HS-NOA, the number of androgen receptor positive Sertoli cells was reduced 30% with a similar pattern in mRNA expression. The γH2AX expression was increased in SCO as compared to HS and MA. However, none of these differences reached statistical significance probably due to low number of samples. Conclusions: Sertoli cells were shown to be immature in un-dilated tubules of three NOA subtypes. The increased DNA damage in Sertoli cells and thicker tubule wall in SCO suggested a different mechanism for the absence of spermatogenesis from SCO to HS and MA. These results expand insight into the differences in un-dilated tubules from the different types of NOA patients.
Assuntos
Azoospermia , Oligospermia , Azoospermia/genética , Azoospermia/patologia , Azoospermia/terapia , Humanos , Masculino , Oligospermia/genética , Oligospermia/metabolismo , RNA Mensageiro/metabolismo , Túbulos Seminíferos/metabolismo , Túbulos Seminíferos/patologia , Espermatogônias/metabolismoRESUMO
BACKGROUND: The number of cases of male infertility is steadily growing every year, and therefore it is necessary to develop new methods for the diagnosis and treatment of this disease. It is known that plasma enriched with platelets, the α-granules of which contain growth factors, possesses high regenerative activity; therefore, we can expect positive results from its use for the restoration of spermatogenic epithelium. OBJECTIVE: Morphological assessment of spermatogenesis after local ß-irradiation with a dose of 8 Gy and the introduction of growth factors. MATERIAL AND METHODS: Wistar rats (n=135) were divided into groups: I - Control, II - 8IR, III - 8IR+LP-PRP+IGF, IV - 8IR+LP-PRP, and V - LP-PRP. Spermatogenesis in animals of groups II, III, and IV was inhibited by a single local irradiation with 8 Gy electrons. Then, for 11 weeks, LP-PRP was injected intraperitoneally to rats III and IV, and in group III - additionally IGF-1. The testes were examined by light microscopy, computer morphometry, micro-CT, and Western blotting. RESULTS: After irradiation, a decrease in spermatogenic epithelium and the number of germ cells was observed up to sub- and total germinal aplasia, fibrosis and an increase in the expression of caspase-3. Against the background of LP-PRP+IGF administration, the decrease in the proportion of germ cells (hypospermatogenesis) was less pronounced. CONCLUSION: The introduction of growth factors and other biologically active substances released from the α-granules of LP-PRP platelets leads to a delayed decrease in the quantitative and qualitative indicators of spermatogenesis, and the additional administration of IGF-1 enhances the regenerative processes that counteract the development of the effects of electron irradiation with a dose of 8 Gy.
Assuntos
Plaquetas , Fator de Crescimento Insulin-Like I , Animais , Eletrônica , Humanos , Fator de Crescimento Insulin-Like I/farmacologia , Masculino , Ratos , Ratos Wistar , Espermatogênese , TestículoRESUMO
Male haploid cells, spermatids and spermatozoa, that appear after the establishment of immune tolerance express novel cell surface and intracellular proteins that can be recognized as foreign antigens by the self-immune system. However, these germ cells do not normally evoke a pathological immune response. The immune-privileged micro-circumstance in testis involving the blood-testis-barrier formed by Sertoli cells protects these germ cells from autoimmune attack. We recently found that immunization with heat shock protein family A member 4-like (HSPA4L), one of the new differentiation antigens of haploid cells, induced experimental autoimmune orchitis (EAO) in A/J male mice. In this study, we focused on G protein-coupled receptor kinase interacting protein-1 (GIT1), another haploid cell-specific differentiation antigen, to investigate whether GIT1 is a target autoantigen for EAO induction. GIT1 emulsified with complete Freund's adjuvant was injected subcutaneously into the mice inguinal region once on day 0 and again on day 14, and the optimum condition of EAO induction was determined. Mice immunized with 200 µg GIT1 showed significantly higher incidence of EAO than that of immunization with other concentrations. In particular, significant lymphocytic inflammation and extensive aspermatogenesis were observed in these mice at 120 days after the first immunization. These findings indicate that GIT1 is also a target antigen that induces EAO, like HSPA4L.
Assuntos
Autoantígenos , Doenças Autoimunes , Animais , Autoantígenos/farmacologia , Doenças Autoimunes/etiologia , Doenças Autoimunes/patologia , Proteínas de Ciclo Celular , Modelos Animais de Doenças , Proteínas Ativadoras de GTPase , Masculino , Camundongos , Espermátides/metabolismo , Espermatogênese , Testículo/metabolismoRESUMO
Chronic copper exposure impaired spermatogenesis in adult male mice. The aim of this study was to determine whether chronic copper exposure can induce apoptosis of testicular cell and hypospermatogenesis via disturbing testosterone synthesis in adult male mice. In the present study, sixty CD-1 male mice were randomly divided into four groups, and were continuously administered for 8 weeks by oral gavage with copper sulfate at a dose of 0, 25, 100, and 150 mg/kg/day, respectively. We determined the content of serum and testicular copper, testicular coefficient, testicular histopathology, sperm count and motility, the mRNA and protein levels of Caspase-3, Bax, and Bcl-2, Leydig cell count, testosterone content, testosterone synthetase, and testosterone synthesis-related genes. The results showed that the copper levels in serum increased in a dose-dependent manner, and the copper levels in testes were significantly related to serum copper levels. Male mice given copper sulfate 100 and 150 dosage groups showed significant decreased in sperm motility and sperm number as well as increased in testes damage, and there was no significant change in testicular coefficient in the four groups. The mRNA levels of Bcl-2 decreased and Caspase-3 increased in 150 dosage group, and Bax increased in two higher dosage groups. Meanwhile, Caspase-3 and Bax proteins increased in 150 dosage group, and Bcl-2 protein decreased in three copper treatment groups. Nevertheless, there were no differences on the levels of testosterone content and testosterone synthetase of 3ß-HSD, 17ß-HSD, 17α-Hyd, and 20α-Hyd, mRNA levels of Cyp11a1, Cyp17a1, and Star, and quantity of Leydig cells in four groups. Overall, these data showed that chronic copper exposure led to copper residues in the testes, and the doses of 100 and 150 mg/kg/day copper sulfate may induce hypospermatogenesis by increasing apoptosis without affecting testosterone secretion.
Assuntos
Apoptose/efeitos dos fármacos , Sulfato de Cobre/farmacologia , Espermatogênese/efeitos dos fármacos , Testículo/efeitos dos fármacos , Testosterona/metabolismo , Administração Oral , Animais , Sulfato de Cobre/administração & dosagem , Sulfato de Cobre/análise , Masculino , Camundongos , Testículo/metabolismo , Testículo/patologia , Testosterona/sangueRESUMO
Ubiquitin conjugating enzyme (E2) is crucial for mediating N-terminal ubiquitination. Recent study reports that UBE2W is involved in male infertility. However, the correlation between UBE2W expression and hypospermatogenesis is unclear. The present study is to explore the biological role of UBE2W and its association with hypospermatogenesis. Results showed that the sexpression levels of UBE2W in mouse testes were gradually elevated from 2 to 10 weeks, while were significantly deceased in the testes with hypospermatogenesis. When UBE2W expression was successfully down-regulated in spermatogenic cells, the rate of apoptosis was significantly increased and the P53/Bcl-2/caspase 6/caspase 9 signal pathways were activated. Thus, these data indicate that UBE2W down-regulation promotes cell apoptosis and correlates with hypospermatogenesis, which may be helpful for the diagnosis of male infertility.
Assuntos
Azoospermia/patologia , Espermatogênese/fisiologia , Testículo/patologia , Enzimas de Conjugação de Ubiquitina/metabolismo , Animais , Apoptose , Azoospermia/induzido quimicamente , Azoospermia/fisiopatologia , Bussulfano/toxicidade , Linhagem Celular , Dimetil Sulfóxido/toxicidade , Modelos Animais de Doenças , Regulação para Baixo , Humanos , Masculino , Camundongos , RNA Interferente Pequeno/metabolismo , Espermatócitos , Espermatogônias , Enzimas de Conjugação de Ubiquitina/genéticaRESUMO
Phosphoribosyl-pyrophosphate synthetase 2 (PRPS2) is a rate-limiting enzyme and plays an important role in purine and pyrimidine nucleotide synthesis. Recent studies report that PRPS2 is involved in male infertility. However, the role of PRPS2 in hypospermatogenesis is unknown. In this study, the relationship of PRPS2 with hypospermatogenesis and spermatogenic cell apoptosis was investigated. The results showed that PRPS2 depletion increased the number of apoptotic spermatogenic cells in vitro. PRPS2 was downregulated in a mouse model of hypospermatogenesis. When PRPS2 expression was knocked down in mouse testes, hypospermatogenesis and accelerated apoptosis of spermatogenic cells were noted. E2F transcription factor 1 (E2F1) was confirmed as the target gene of PRPS2 and played a key role in cell apoptosis by regulating the P53/Bcl-xl/Bcl-2/Caspase 6/Caspase 9 apoptosis pathway. Therefore, these data indicate that PRPS2 depletion contributes to the apoptosis of spermatogenic cells and is associated with hypospermatogenesis, which may be helpful for the diagnosis of male infertility.
Assuntos
Apoptose/genética , Fator de Transcrição E2F1/metabolismo , Oligospermia/genética , Ribose-Fosfato Pirofosfoquinase/genética , Ribose-Fosfato Pirofosfoquinase/metabolismo , Animais , Caspase 6/metabolismo , Caspase 9/metabolismo , Linhagem Celular , Modelos Animais de Doenças , Regulação para Baixo , Fator de Transcrição E2F1/genética , Expressão Gênica , Técnicas de Silenciamento de Genes , Masculino , Camundongos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA/metabolismo , Distribuição Aleatória , Transdução de Sinais , Espermatócitos/fisiologia , Testículo/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Regulação para Cima , Proteína bcl-X/metabolismoRESUMO
BACKGROUND: It has been proposed that lncRNAs, widely transcribed from genomes, play pivotal regulatory roles in a variety of biological processes, but their function in regulating spermatogenesis in human males is rarely reported. METHODS: QRT-PCR was adopted to detect HOTTIP expression level in testicular tissues from hypospermatogenesis (Hypo) patients or controls. The proliferation levels of NT2 and 293T were measured via CCK-8 and EdU detection. Meanwhile, luciferase reporter gene assay and bioinformatics analysis were carried out to identify a target of HOTTIP. Additionally, the underlying mechanism of HOTTIP's function was investigated using western blotting and RIP analysis. RESULTS: The research results manifested that the expression of HOTTIP in testicular tissues from Hypo patients was prominently reduced in comparison with that in control testicular tissues. Interestingly, it was noted that HOTTIP exhibited a high expression in testicular embryonal carcinoma cell line NT2 compared with that in normal control cell line 293T. It was denoted in cell function evaluation that cell proliferation was impeded by downregulated HOTTIP but evidently stimulated by overexpressed HOTTIP. Moreover, HOTTIP was capable of positively modulating HOXA13 expression via the competitive binding to miR-128-3p. CONCLUSION: Therefore, HOTTIP acting as ceRNAs to promote testicular embryonal carcinoma cell proliferation.
Assuntos
Predisposição Genética para Doença , Infertilidade Masculina/genética , RNA Longo não Codificante/genética , Neoplasias Testiculares/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Estudos de Associação Genética , Células HEK293 , Humanos , Infertilidade Masculina/diagnóstico , Masculino , Transporte de RNA , Neoplasias Testiculares/patologiaRESUMO
OBJECTIVE: To study the expression of CLAUDIN-11 in the testis tissue of non-obstructive azoospermia (NOA) patients with different severities and investigate its clinical significance. METHODS: Sixty-two NOA patients were divided into a hypospermatogenesis (HS) group (n = 30) and a Sertoli cell only syndrome (SCO) group (n =32). The expression of CLAUDIN-11 in the testicular tissue of the patients was detected by immunohistochemistry, that of CLAUDIN-11 mRNA determined by real-time fluorescence quantitative polymerase chain reaction (RT-qPCR), and the levels of serum reproductive hormones measured by chemiluminescent immunoassay. RESULTS: Immunohistochemistry showed that the expression of CLAUDIN-11 was mainly in the cytoplasm of the Sertoli cells around the seminiferous tubule wall in the HS group, but diffusely distributed in the membrane of the Sertoli cells in the SCO group. RT-qPCR revealed a significantly lower expression of CLAUDIN-11 mRNA in the HS than in the SCO group (0.008 ± 0.001 vs 0.013 ± 0.002, t = 10.616, P<0.01). The level of serum luteotropic hormone (LH) was also markedly lower in the HS than in the SCO group (ï¼»3.62 ± 1.34ï¼½ vs ï¼»4.96 ± 3.10ï¼½ IU/L, P<0.05) and so was that of follicle-stimulating hormone (FSH) (ï¼»5.36 ± 2.80ï¼½ vs ï¼»10.65 ± 9.18ï¼½ IU/L, P<0.05). CONCLUSIONS: The up-regulated expression of CLAUDIN-11 in Sertoli cells may play an important role in the development and progression of spermatogenic dysfunction in NOA patients.
Assuntos
Azoospermia/metabolismo , Claudinas/metabolismo , Oligospermia/metabolismo , Síndrome de Células de Sertoli/metabolismo , Testículo/metabolismo , Azoospermia/genética , Hormônio Foliculoestimulante/metabolismo , Humanos , Masculino , Oligospermia/genética , RNA Mensageiro/metabolismo , Túbulos Seminíferos/metabolismo , Síndrome de Células de Sertoli/genética , Células de Sertoli/metabolismo , EspermatogêneseRESUMO
Clinical findings and a variety of experimental models indicate that Leydig cell dysfunction accompanies damage to the seminiferous tubules with increasing severity. Most studies support the idea that intratesticular signaling from the seminiferous tubules to Leydig cells regulates steroidogenesis, which is disrupted when hypospermatogenesis occurs. Sertoli cells seem to play a pivotal role in this process. In this review, we summarize relevant clinical and experimental observations and present evidence to support the hypothesis that testicular activin signaling and its regulation by testicular inhibin may link seminiferous tubular dysfunction to reduced testosterone biosynthesis.
Assuntos
Ativinas/metabolismo , Inibinas/metabolismo , Células Intersticiais do Testículo/metabolismo , Oligospermia/metabolismo , Animais , Humanos , Masculino , Túbulos Seminíferos/metabolismo , Túbulos Seminíferos/fisiopatologia , Transdução de Sinais , Testosterona/biossínteseRESUMO
Sodium-dependent organic anion transporter (SOAT) represents a membrane transporter specific for sulfated steroid hormones, which are supposed to participate in the regulation of reproductive processes. In man, SOAT shows predominant mRNA expression in the testis and here was localized to primary spermatocytes. SOAT mRNA expression is significantly downregulated in different disorders of spermatogenesis, including hypospermatogenesis. The resulting decline of SOAT-mediated transport of sulfated steroids may participate in the impairment of functional spermatogenesis. Apart from downregulation of SOAT mRNA expression, genetic polymorphisms affecting the transport function of SOAT may have the same negative effect on spermatogenesis. Therefore, in the present study we searched for functionally relevant SOAT polymorphisms, aiming to comparatively analyze their occurrence in patients with impaired spermatogenesis vs. patients with intact spermatogenesis. We found that the SOAT polymorphism L204F showed a significantly reduced transport function for DHEAS when expressed in HEK293 cells. Although the Km value was identical with that of the SOAT wildtype, the Vmax value dramatically declined for the SOAT-L204F variant (942.5 vs. 313.6pmol×mg protein-1×min-1). Although the same amount of total SOAT-L204F protein was detected in transfected HEK293 cells compared to the SOAT wildtype, plasma membrane expression was significantly reduced, which points to a plasma membrane sorting defect of the SOAT-L204F variant. Groups of 20 subjects with normal spermatogenesis and 26 subjects with hypospermatogenesis were genotyped for this polymorphism. Both groups showed nearly identical distributions of the SOAT-L204F polymorphism (â¼10% heterozygous and â¼5% homozygous), indicating that this polymorphism seems not be causative for hypospermatogenesis.
Assuntos
Transportadores de Ânions Orgânicos/genética , Transportadores de Ânions Orgânicos/metabolismo , Polimorfismo de Nucleotídeo Único , Espermatogênese/genética , Transporte Biológico , Membrana Celular/metabolismo , Sulfato de Desidroepiandrosterona/metabolismo , Células HEK293 , Humanos , Masculino , Oligospermia/genética , Testículo/fisiologiaRESUMO
STUDY QUESTION: Does the hypermethylation of the maelstrom spermatogenic transposon silencer (MAEL) promoter and subsequent de-repression of transposable elements represent one of the causes of spermatogenic failure in infertile men? SUMMARY ANSWER: Experimental hypermethylation of a specific region (-131 to +177) of the MAEL promoter leads to decreased expression of MAEL with increased expression of the transposable element LINE-1 (L1) and in infertile men methylation of the MAEL promoter is associated with the severity of spermatogenic failure. WHAT IS KNOWN ALREADY: MAEL induces transposon repression in the male germline and is required for mammalian meiotic progression and post-meiotic spermiogenesis. Patients with non-obstructive azoospermia (NOA), defined as no sperm in the ejaculate due to spermatogenic failure, and histopathologically proven hypospermatogenesis (HS) is not uncommon and its etiology is largely unknown. STUDY DESIGN, SIZE, DURATION: Luciferase reporter assay and a targeted DNA methylation model were used to explore the effects of hypermethylation of MAEL promoter on gene expression. Germ cell-enriched testicular cells from infertile patients were used to determine the methylation levels of MAEL and expressions of MAEL and L1. PARTICIPANTS/MATERIALS, SETTING, METHODS: Twenty-six patients with histopathologically proven NOA and HS and 12 patients with obstructive azoospermia and normal spermatogenesis (NS) were enrolled in this study. Demographic and clinical information were obtained. The severity of HS was determined by a spermatogenic scoring system. The methylation levels of 26 CpGs in the MAEL promoter was measured, and quantitative real-time RT-PCR was used to determine the expressional levels of MAEL and L1. MAIN RESULTS AND THE ROLE OF CHANCE: Targeted DNA methylation of MAEL promoter suppressed MAEL expression and de-repressed L1 activity in vitro. Patients with HS had significantly higher mean methylation levels of 26 consecutive CpGs in the MAEL promoter, compared to patients with NS. The MAEL methylation levels were negatively correlated with MAEL transcript levels and higher methylation level of MAEL was associated with severe spermatogenic defect. L1 transcript level was significantly higher in patients with HS. No differences in age, frequency of testicular insults and genetic anomalies was noted between patients with high or low MAEL methylation levels. LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: Because of the difficulty in the use of human germ cells for study, the in vitro targeted DNA methylation model was performed by using human NCI-H358 cells to explore the effects of MAEL methylation on transposable elements activity. Because the germ cell-enriched testicular cells isolated from a testicular sample were relatively few, the purity of cell populations was not determined. WIDER IMPLICATIONS OF THE FINDINGS: Measurement of the methylation level of MAEL gene may be feasible to predict the severity of spermatogenic failure or the outcome of testicular sperm retrieval. STUDY FUNDING/COMPETING INTERESTS: This work was supported through grants from the Ministry of Science and Technology of Taiwan (100-2314-B-006-017) and National Cheng Kung University Hospital, Tainan, Taiwan (NCKUH 20120266). The authors declare no conflicts of interest.
Assuntos
Proteínas de Transporte/genética , Metilação de DNA , Infertilidade Masculina/genética , Elementos Nucleotídeos Longos e Dispersos , Espermatogênese/genética , Adulto , Azoospermia/genética , Linhagem Celular Tumoral , Ilhas de CpG , Elementos de DNA Transponíveis , Proteínas de Ligação a DNA , Inativação Gênica , Genes Reporter , Humanos , Infertilidade Masculina/patologia , Masculino , Oligospermia/genética , Fenótipo , Regiões Promotoras Genéticas , Recuperação Espermática , Espermatozoides/metabolismo , Testículo/metabolismo , Fatores de TranscriçãoRESUMO
This study was performed to assess and compare the outcomes of testicular sperm extraction (TESE)-intracytoplasmic sperm injection (ICSI) using spermatozoa from fresh and frozen testicular tissue from men with subgroups of non-obstructive azoospermia (NOA). A total of 110 cycles of TESE-ICSI were performed. Patients were classified into one of the following NOA subgroups: hypospermatogenesis (HS), maturation arrest (MA), or Sertoli cell-only syndrome (SCO). Laboratory (fertilization, cleavage stage of embryo, and good quality embryo) and clinical (pregnancy, clinical pregnancy, implantation, and delivery) outcomes were assessed. No statistically significant differences were observed in any of the other measured parameters between the three subgroups of NOA. No significant differences in laboratory outcomes were observed between spermatozoa from fresh and frozen testicular spermatozoa; however, statistically significant differences were observed in the pregnancy and implantation rates between groups (p < 0.05). The outcomes of using spermatozoa retrieved from fresh testicular tissue in each of the three subgroups were also compared; although clinical outcomes showed low results, no significant differences were observed between the three subgroups. Similarly, no significant differences were observed in spermatozoa retrieved from frozen testicular tissue. Once spermatozoa have been successfully obtained, acceptable laboratory outcomes can be achieved for NOA, whether or not the spermatozoa are cryopreserved. However, satisfactory clinical outcomes may be more difficult to achieve as the results showed in each group of fresh and frozen testicular spermatozoa. Therefore, achieving acceptable clinical pregnancy results and efficient cryopreservation of testicular spermatozoa should be considered in patients with NOA.
Assuntos
Azoospermia/cirurgia , Embrião de Mamíferos , Desenvolvimento Embrionário , Recuperação Espermática , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Gravidez , Taxa de Gravidez , Injeções de Esperma Intracitoplásmicas/estatística & dados numéricos , EspermatozoidesRESUMO
OBJECTIVE: To identify and categorize various pathological changes seen in testicular biopsies of males with infertility and to compare the results with data from other local and international studies. MATERIALS AND METHODS: All testicular biopsies from males with infertility received by the Pathology Department of King AbdulAziz University Hospital, Jeddah, in the period from January 2004 until May 2010 are reviewed and histopathologically classified into seven categories as follows : Normal spermatogenesis, hypospermatogenesis, germ cell maturation arrest (GCMA), Sertoli cell only syndrome, seminiferous tubule hyalinization, mixed and discordant patterns. RESULTS: One hundred testicular biopsies were identified in the computerized records of the Department of Pathology of King AbdulAziz University Hospital in the studied period. The age ranged from 22 to 70 years with a mean age of 24.5 years. The histopathological patterns were as follows: 14 (14%) cases were reported as normal spermatogenesis;(29, 29%) cases as hypospermatogesis; and 12 (12%) cases were reported as GCMA, mostly at the level of primary spermatocytes. The Sertoli cell only syndrome and the seminiferous tubule hyalinization categories were each reported in 16 cases (16%). Nine cases (9%) showed a mixed pattern. Discordant pattern was seen in 5 (5%) cases. CONCLUSION: Our study showed that hypospermatogenesis is the commonest pattern in testicular biopsies taken from males with infertility in our region. This study supports the recommendation of bilateral testicular biopsies when investigating male infertility.
RESUMO
Gonadotropins (FSH, LH) and testosterone are the prime regulators of germ cell development. Abnormal spermatogenesis is often associated with altered serum gonadotropins and testosterone. FSH, LH and testosterone levels were estimated in 96 infertile men of whom 35 were azoospermic, 35 were oligozoospermic, 11 were with varicocele and 15 were with histopathological abnormalities like hypospermatogenesis, spermatid arrest and sertoli-cell only syndrome. Results showed statistically significant (p<0.05), increase in the mean FSH and LH levels in all the infertile males studied when compared with the fertile controls (n=35). However, there is no significant difference in the mean levels of testosterone between the infertile and fertile men.