Association between MTHFR c.677C>T variant and erectile dysfunction among males attending fertility clinic.

ABSTRACT: Genetic risk factors have been shown to contribute to the development of sexual dysfunction. However, the role of methylenetetrahydrofolate reductase (MTHFR) gene variants in the risk of erectile dysfunction (ED) remains unclear. In this study, we recruited 1254 participants who underwent ED assessed by the International Index of Erectile Function-5. The MTHFR c.677C>T variant was also measured by fluorescence polymerase chain reaction (PCR). No significant difference in the genotypic frequency of the MTHFR C677T polymorphism (CC, CT, and TT) was observed between men from the ED and non-ED groups. In addition, on binary logistic regression analysis, both crude and adjusted models showed that the risk of ED was not significantly associated with the C677T polymorphism. Interestingly, a significantly higher frequency of the 677TT polymorphism was found in severe and moderate ED (P = 0.02). The positive correlation between the MTHFR 677TT polymorphism and severe ED was confirmed by logistic regression analysis, even after adjusting for potential confounders (odds ratio [OR] = 2.46, 95% confidence interval [CI]: 1.15-5.50, P = 0.02). These findings suggest a positive correlation between the MTHFR 677TT polymorphism and the risk of severe ED. Identification of MTHFR gene polymorphisms may provide complementary information for ED patients during routine clinical diagnosis.

Loss-of-function variants in KCTD19 cause non-obstructive azoospermia in humans.

Azoospermia is a significant cause of male infertility, with non-obstructive azoospermia (NOA) being the most severe type of spermatogenic failure. NOA is mostly caused by congenital factors, but our understanding of its genetic causes is very limited. Here, we identified a frameshift variant (c.201_202insAC, p.Tyr68Thrfs∗17) and two nonsense variants (c.1897C>T, p.Gln633∗; c.2005C>T, p.Gln669∗) in KCTD19 (potassium channel tetramerization domain containing 19) from two unrelated infertile Chinese men and a consanguineous Pakistani family with three infertile brothers. Testicular histological analyses revealed meiotic metaphase I (MMI) arrest in the affected individuals. Mice modeling KCTD19 variants recapitulated the same MMI arrest phenotype due to severe disrupted individualization of MMI chromosomes. Further analysis showed a complete loss of KCTD19 protein in both Kctd19 mutant mouse testes and affected individual testes. Collectively, our findings demonstrate the pathogenicity of the identified KCTD19 variants and highlight an essential role of KCTD19 in MMI chromosome individualization.

Sexually transmitted infections and semen quality from subfertile men with and without leukocytospermia.

BACKGROUND: The role of sexually transmitted infections (STIs) in semen parameters and male infertility is still a controversial area. Previous studies have found bacterial infection in a minority of infertile leukocytospermic males. This study aims to investigate the prevalence of STIs in semen from subfertile men with leukocytospermia (LCS) and without leukocytospermia (non-LCS) and their associations with sperm quality. METHODS: Semen samples were collected from 195 men who asked for a fertility evaluation. Infection with the above 6 pathogens was assessed in each sample. Sperm quality was compared in subfertile men with and without LCS. RESULTS: The LCS group had significantly decreased semen volume, sperm concentration, progressive motility, total motility and normal morphology. The infection rates of Ureaplasma urealyticum (Uuu), Ureaplasma parvum (Uup), Mycoplasma hominis (MH), Mycoplasma genitalium (MG), Chlamydia trachomatis (CT), herpes simplex virus-2 (HSV-2) and Neisseria gonorrhoeae (NG) were 8.7 %, 21.0 %, 8.2 %, 2.1 %, 3.6 %, 1.0 and 0 %, respectively. The STI detection rates of patients with LCS were higher than those of the non-LCS group (52.3 % vs. 39.3 %), although there was no statistically significant difference between the two groups (P = 0.07). All semen parameters were not significantly different between LCS with STIs and without STIs, except the semen volume in the MG-infected patients with LCS was significantly lower than that in the noninfected group. CONCLUSIONS: LCS was associated with a reduction in semen quality, but was not associated with STIs.

Semen parameters in men recovered from COVID-19.

The novel coronavirus disease (COVID-19) pandemic is emerging as a global health threat and shows a higher risk for men than women. Thus far, the studies on andrological consequences of COVID-19 are limited. To ascertain the consequences of COVID-19 on sperm parameters after recovery, we recruited 41 reproductive-aged male patients who had recovered from COVID-19, and analyzed their semen parameters and serum sex hormones at a median time of 56 days after hospital discharge. For longitudinal analysis, a second sampling was obtained from 22 of the 41 patients after a median time interval of 29 days from first sampling. Compared with controls who had not suffered from COVID-19, the total sperm count, sperm concentration, and percentages of motile and progressively motile spermatozoa in the patients were significantly lower at first sampling, while sperm vitality and morphology were not affected. The total sperm count, sperm concentration, and number of motile spermatozoa per ejaculate were significantly increased and the percentage of morphologically abnormal sperm was reduced at the second sampling compared with those at first in the 22 patients examined. Though there were higher prolactin and lower progesterone levels in patients at first sampling than those in controls, no significant alterations were detected for any sex hormones examined over time following COVID-19 recovery in the 22 patients. Although it should be interpreted carefully, these findings indicate an adverse but potentially reversible consequence of COVID-19 on sperm quality.

Association of Alcohol Intake and Semen Parameters in Men With Primary and Secondary Infertility: A Cross-Sectional Study.

Alcohol consumption has commonly been associated with semen parameters. However, the association between alcohol intake and semen parameters in primary and secondary infertile men remains unclear. In this study, 776 infertile men from China were grouped according to alcohol intake: abstainers, moderate drinkers (<9 units/week, up to approximately 100 g of ethanol) and heavy drinkers (≥9 units/week). Semen parameters, including semen volume, sperm concentration, total sperm count, progressive motility and normal morphology were investigated. Alcohol consumption and other lifestyle factors were assessed by questionnaire. Logistic regression models were applied. There was no significant association between alcohol consumption and semen parameters in men with primary infertility. Smaller testis volumes and lower sperm concentrations were found among moderate and heavy drinkers in the secondary infertility group than among abstainers. After adjustment for potential confounders, men with secondary infertility and heavy alcohol consumption had a higher risk of abnormal sperm concentrations (OR = 3.72; 95% CI, 1.04, 13.37). These findings suggest that alcohol intake may decrease sperm concentrations in men with secondary infertility, whereas no association was found in men with primary infertility. It may be beneficial for clinicians to advise male patients with secondary infertility who are seeking fertility treatment to avoid heavy alcohol consumption.

Compound heterozygosity for novel AURKC mutations in an infertile man with macrozoospermia.

Among causes of infertility, teratozoospermia is characterised by a percentage of morphologically abnormal spermatozoa >4%. Macrozoospermia, one form of monomorphic teratozoospermia, is observed in <1% of cases of male infertility and is described as approximately 100% large-headed and/or multitailed spermatozoa. This study reports that an infertile man with large-head spermatozoa presenting compound heterozygosity aurora kinase C (AURKC) mutations (c.382C>T, c.572C>T) by whole-exome sequencing. Consequently, both two novel AURKC mutations had high probability of damage-causing and conserved across species and extremely low allele frequency in the population. Flow cytometry analysis revealed a high ratio of sperm DNA fragmentation. Two intracytoplasmic sperm injection (ICSI) procedures were attempted for the patient, but all were unsuccessful. These results indicate that sequence analysis should be performed for the variants of AURKC in Chinese patients with macrozoospermia.

Biallelic mutations in Sperm flagellum 2 cause human multiple morphological abnormalities of the sperm flagella (MMAF) phenotype.

Male patients with multiple morphological abnormalities of the sperm flagella (MMAF) are infertile and exhibit absent, short, coiled, bent and/or irregular sperm flagella. Mutations in the SPEF2 gene reduce sperm motility and cause sperm tail defects in animal models and humans. In the present study, we performed a genetic analysis on an MMAF patient and identified novel biallelic mutations in the SPEF2 gene. The biallelic mutations were confirmed by Sanger sequencing and in silico analysis revealed that, these variations were deleterious. The expression of truncated SPEF2 protein was reduced significantly in the patient's spermatozoa. The spermatozoa harbored biallelic mutations and showed severe ultrastructural defects in the axoneme and mitochondrial sheath. Our data suggest that biallelic mutations in SPEF2 can cause severe sperm flagellum defects, thus providing a novel candidate genetic pathogen for the human MMAF phenotype.

Meiotic defects and decreased expression of genes located around the chromosomal breakpoint in the testis of a patient with a novel 46,X,t(Y;1)(p11.3;p31) translocation.

Balanced translocations are known to be associated with infertility, spontaneous abortions and birth defects in mammals. Spermatocyte spreading and immunostaining were applied to detect meiotic prophase I progression, homologous chromosome pairing, synapsis and recombination in an azoospermic reciprocal translocation 46,X,t(Y;1)(p11.3;p31) carrier. Histological examination of testicular sections revealed a severely reduced number of germ cells with no spermatids or sperm in the carrier. A significant reduction in XY recombination was observed in the patient. The number of MLH1 foci on autosomes that are not involved in the translocation per cell was also significantly decreased in our patient as compared to the controls, which indicates an inter-chromosomal effect (ICE) of the translocation on recombination. An increase in leptotene (P<0.001) and zygotene (P<0.001) and a decrease in pachytene spermatocytes (P<0.001) were observed in the carrier when compared with the controls, indicating disturbed meiotic progression in the patient. Increased RAD51 foci during pachytene (P=0.02) in the spermatocytes of the patient were noted. A decreased expression of the genes (USP1, INSL5, LEPR and MSH4) critical for meiosis/spermatogenesis and located around the breakpoint region of chromosome 1 was observed in the 46,X,t(Y;1) carrier, which may further exacerbate the meiotic failure such as reduced recombination on autosomes and ultimately cause spermatogenesis arrest. In summary, we report a series of events that may have caused infertility in our 46,X,t(Y;1) carrier. To the best of our knowledge, this is the first report shedding light on how, possibly, a reciprocal translocation affects meiosis at the molecular level in azoospermia patients.

Preferential Y-Y pairing and synapsis and abnormal meiotic recombination in a 47,XYY man with non obstructive azoospermia.

BACK GROUND: Men with 47, XYY syndrome are presented with varying physical attributes and degrees of infertility. Little information has been documented regarding the meiotic progression in patients with extra Y chromosome along with the synapses and recombination between the two Y chromosomes. METHODS: Spermatocyte spreading and immunostaining were applied to study the behavior of the extra Y chromosome during meiosis I in an azoospermia patient with 47, XYY syndrome and results were compared with five healthy controls with proven fertility. RESULTS: The extra Y chromosome was present in all the studied spermatocytes of the patient and preferentially paired and synapsed with the other Y chromosome. Consistently, gamma-H2AX staining completely disappeared from the synapsed regions of Y chromosomes. More interestingly, besides recombination on short arms, recombination on the long arms of Y chromosomes was also observed. No pairing and synapsis defects between homologous autosomes were detected, while significantly reduced recombination frequencies on autosomes were observed in the patient. The meiotic prophase I progression was disturbed with significantly increased proportion of leptotene, zygotene cells and decreased pachytene spermatocytes in the patient when compared with the controls. CONCLUSIONS: These findings highlight the importance of studies on meiotic behaviors in patients with an abnormal chromosomal constitution and provide an important framework for future studies, which may elucidate the impairment caused by extra Y chromosome in mammalian meiosis and fertility.

MiR-302a inhibits the tumorigenicity of ovarian cancer cells by suppression of SDC1.

MicroRNA plays an important role in tumor proliferation and cell cycle. In this study, we suggested the level of miR-302a was increasing in the human ovarian cancer cells compared to the normal cells. We aimed to explore the role of miR-302a downregulation in human ovarian cancer cells. Functional studies demonstrate over expression of miR-302a could significant suppress ovarian cancer cells proliferation and promote the cell cycle progress. In vitro reporter assay suggested SDC1 is a direct target gene of miR-302a. Furthermore, the expressions of miR-302a in ovarian cancer cells were inversely corrected with that of SDC1. Upregulation of SDC1 could rescue the effect of over expressed miR-302a in the ovarian cancer cells. These findings provide evidence that miR-302a plays a key role in inhibition of the ovarian cancer cells proliferation, and enhancing the cells' apoptosis through targeting SDC1, and strongly suggest that exogenous miR-302a may have therapeutic value in treating ovarian cancer.

Meiotic chromosome behavior in a human male t(8;15) carrier.

Reciprocal translocation is one of the most common structural chromosomal rearrangements in human beings; it is widely recognized to be associated with male infertility. This association is mainly based on the abnormal chromosome behavior of the translocated chromosomes and sex chromosomes during meiosis prophase I in reciprocal translocation carriers. However, the underlying mechanisms are not completely known. Here we report a reciprocal translocation carrier of t(8;15), who is oligozoospermic due to apoptosis of primary spermatocytes and to premature germ cell desquamation from seminiferous tubules. Further analysis showed abnormal synapsis and recombination frequency in this patient, indicating a connection between chromosome behavior and apoptosis of primary spermatocytes. We also compared these observations with recently reported findings on spermatogenesis defects in reciprocal translocation carriers, and discuss the possible mechanisms underlying both common and unique phenotypes of reciprocal translocations involving different chromosomes with the aim of further understanding the regulation of human spermatogenesis.

[Ultra-rapid cryopreservation of human spermatozoa with different concentrations of sucrose].

OBJECTIVE: To explore the feasibility of ultra-rapid freezing of human spermatozoa in the cryogenic vial with different concentrations of sucrose solution. METHODS: We divided 40 normal semen samples prepared with the routine swim-up technique into 6 aliquots, 1 as the control and the other 5 cryopreserved with sucrose solution at the concentrations of 0.15, 0.20, 0.25 and 0.30 mol/L, respectively. After thawing, we determined and compared the motility, progressive motility and plasma membrane integrity of the sperm among the 6 groups. RESULTS: The motility, progressive motility and plasma membrane integrity of the sperm were significantly lower after thawing than before cryopreservation ([96.2 +/- 1.8]%, [93.8 +/- 2.8]% and [99.0 +/- 0.8 ]%) (P<0.05). Post-thawing sperm motility was (55.5 +/- 6.3)% in the 0.20 mol/L sucrose group, significantly higher than in the 0.15, 0.25 and 0.30 mol/L groups ([45.9 +/- 6.6]%, [50.4 +/- 9.4]% and [45.5 +/- 11.2]%) (P<0.05), and it was (53.6 +/- 5.0)% in the conventional freezing group, with no statistically significant difference from the 0.20 and 0.25 mol/L sucrose cryopreservation groups (P> 0.05), but remarkably higher than in the 0.15 and 0.30 mol/L groups (P<0.05). Post-thawing progressive sperm motility exhibited no statistically significant differences between the 0.20 mol/L sucrose and conventional freezing groups ([44.4 +/- 7.4]% vs [42.3 +/- 8.1]%, P>0.05), but markedly higher in both than in the 0.15, 0.25 and 0.30 mol/L sucrose groups ([37.1 +/- 8.3 ]%, [33.1 +/- 9.2]% and [22.0 +/- 9.1]%) (P<0.05). Post-thawing plasma membrane integrity was significantly higher in the 0.20 mol/L sucrose cryopreservation group ( [70.1 +/- 6.9]%) than in either the conventional freezing group ([63.1 +/- 6.8]%) or the 0.15, 0.25 and 0.30 mol/L sucrose groups ([57.7 +/- 8.3]%, [63.5 +/- 10.7]% and [57.8 +/- 12.9]%) (P<0.05). CONCLUSION: As a simple, safe and effective method, ultra-rapid freezing with sucrose solution at the final concentration of 0.20 mol/L can be used for the cryopreservation of human spermatozoa.