Identity suffering in infertile men

Is BRD7 associated with spermatogenesis impairment and male infertility in humans? A case-control study in a Han Chinese population

Background

Bromodomain-containing protein 7 (BRD7), a member of the bromodomain-containing protein family, plays important roles in chromatin modification and transcriptional regulation. A recent model of Brd7-knockout mice presented azoospermia and male infertility, implying the potential role of BRD7 in spermatogenic failure in humans. This case-control study aimed to explore the association of the BRD7 gene with spermatogenic efficiency and the risk of spermatogenic defects in humans.

Results

A total of six heterozygous variants were detected in the coding and splicing regions of the BRD7 gene in patients with azoospermia. For each of four rare variants predicted to potentially damage BRD7 function, we further identified these four variants in oligozoospermia and normozoospermia as well. However, no difference in the allele and genotype frequencies of rare variants were observed between cases with spermatogenic failure and controls with normozoospermia; the sperm products of variant carriers were similar to those of noncarriers. Moreover, similar distribution of the alleles, genotypes and haplotypes of seven tag single nucleotide polymorphisms (tagSNPs) was observed between the cases with azoospermia and oligozoospermia and controls with normozoospermia; associations of tagSNP-distinguished BRD7 alleles with sperm products were not identified.

Conclusions

The lack of an association of BRD7-linked rare and common variants with spermatogenic failure implied a limited contribution of the BRD7 gene to spermatogenic efficiency and susceptibility to male infertility in humans.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12610-021-00139-3.

Peroxiredoxins prevent oxidative stress during human sperm capacitation

STUDY QUESTION

Do peroxiredoxins (PRDXs) control reactive oxygen species (ROS) levels during human sperm capacitation?

SUMMARY ANSWER

PRDXs are necessary to control the levels of ROS generated during capacitation allowing spermatozoa to achieve fertilizing ability.

WHAT IS KNOWN ALREADY

Sperm capacitation is an oxidative event that requires low and controlled amounts of ROS to trigger phosphorylation events. PRDXs are antioxidant enzymes that not only act as scavengers but also control ROS action in somatic cells. Spermatozoa from infertile men have lower levels of PRDXs (particularly of PRDX6), which are thiol-oxidized and therefore inactive.

STUDY DESIGN, SIZE, DURATION

Semen samples were obtained from a cohort of 20 healthy nonsmoker volunteers aged 22-30 years old over a period of 1 year.

PARTICIPANTS/MATERIALS, SETTINGS, METHODS

Sperm from healthy donors was capacitated with fetal cord serum ultrafiltrate (FCSu) in the absence or presence of thiostrepton (TSP), inhibitor of 2-Cys PRDXs or 1-Hexadecyl-3-(trifluoroethyl)-sn-glycero-2-phosphomethanol lithium (MJ33), inhibitor of calcium independent-phospholipase A2 (Ca2+-iPLA2) activity of PRDX6, added at different times of incubation. Capacitation was also induced by the dibutyryl cAMP+3-isobuty1-1-methylxanthine system. Sperm viability and motility were determined by the hypo-osmotic swelling test and computer-assisted semen analysis system, respectively. Capacitation was determined by the ability of spermatozoa to undergo the acrosome reaction triggered by lysophosphatidylcholine. Percentages of acrosome reaction were obtained using the FITC-conjugated Pisum sativum agglutinin assay. Phosphorylation of tyrosine residues and of protein kinase A (PKA) substrates were determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis immunoblotting with specific antibodies. Actin polymerization was determined by phalloidin labeling.

MAIN RESULTS AND THE ROLE OF CHANCE

TSP and MJ33 prevented sperm capacitation and its associated actin polymerization in spermatozoa incubated with 10% FCSu (capacitation inducer) compared to non-capacitated controls (P < 0.05) without altering sperm viability. PKA substrates and tyrosine phosphorylations were prevented in FCSu-treated spermatozoa in a differential fashion depending on the type and the time of addition of the inhibitor used compared to non-capacitated controls (P < 0.05). TSP and MJ33 promoted an increase of lipid peroxidation in spermatozoa (P < 0.01) and these levels were higher in those spermatozoa incubated with the inhibitors and FCSu compared to those capacitated spermatozoa incubated without the inhibitors (P < 0.0001). Inhibition of 2-Cys PRDXs by TSP generated an oxidative stress in spermatozoa, affecting their viability compared to controls (P < 0.05). This oxidative stress was prevented by nuclephile D-penicillamine (PEN). MJ33 also promoted an increase of lipid peroxidation and impaired sperm viability compared to non-treated controls (P < 0.05) but its effect was not circumvented by PEN, suggesting that not only peroxidase but also Ca2+-iPLA2 activity of PRDX6 are necessary to guarantee viability in human spermatozoa.

LARGE SCALE DATA

Not applicable.

LIMITATIONS REASONS FOR CAUTION

We focused on the global effect of PRDXs inhibitors on human sperm capacitation and in two of its associated phosphorylation events. Thus, other phosphorylation events and mechanisms necessary for capacitation may also be affected.

WIDER IMPLICATIONS OF THE FINDINGS

PRDXs are the major antioxidant system in ejaculated spermatozoa and are necessary to allow spermatozoon to achieve fertilizing ability (capacitation and acrosome reaction).

STUDY FUNDING/COMPETING INTEREST(S)

This research was supported by Canadian Institutes of Health Research (MOP 133661) and the Fonds de Recherché en Santé Quebec (FRSQS #22151) to C.O. The authors have nothing to disclose.

To be or not to be [fertile], that is the question

Background

According to our literature analysis, there are no data focused on spermatozoa emotional representations in childless men and data on the emotional repercussions of a diagnosis of infertility on men are still scarce. Thus, in this work, we investigated what the presence or absence of spermatozoa in the semen symbolize for men.

Material and methods

To answer this question, 441 childless heterosexual men participated in an anonymous, prospective, Internet-based survey.

Results

In response to the question “What would having a high or normal sperm count symbolize for you?” the most frequent answer was “ability to father a child”. Men living with a partner were significantly more likely than single men to answer “ability to father a child” (p < 0.05) and less likely to answer “virility” and/or “ability to have an erection/ejaculation” (p = 0.001). In response to the question “If you found out that you had a low sperm count or no spermatozoa at all, how would you feel?”, most of the men stated that they would be disappointed. Men living with a partner were more likely to state that they would feel ashamed (p < 0.05) or guilty with regard to their partner (p < 0.0001).

Conclusions

These preliminary results should help us to improve (i) the way that male infertility is announced (it is easier to find the right words if one understands the possible importance of having a high sperm count) and (ii) the psychological, marital and sexual counselling provided to men with a diagnosis of infertility.

"So Much of This Story Could Be Me": Men's Use of Support in Online Infertility Discussion Boards

Past research has suggested that social support can reduce the negative psychological consequences associated with infertility. Online discussion boards (ODBs) appear to be a novel and valuable venue for men with fertility problems to acquire support from similar others. Research has not employed a social support framework to classify the types of support men are offered and receive. Using template, content, and thematic analysis, this study sought to identify what types of social support men seek and receive on online infertility discussion boards while exploring how men having fertility problems use appraisal support to assist other men. One hundred and ninety-nine unique users were identified on two online infertility discussion boards. Four types of social support (appraisal, emotional, informational, and instrumental) were evident on ODBs, with appraisal support (36%) being used most often to support other men. Within appraisal support, five themes were identified that showed how men communicate this type of support to assist other men: “At the end of the day, we’re all emotionally exhausted”; “So much of this could be me, infertility happens more than you think”; “I’ve also felt like the worst husband in the world”; “It’s just something that nobody ever talks about so it’s really shocking to hear”; “I say this as a man, you’re typing my thoughts exactly.” These findings confirm how ODBs can be used as a potential medium to expand one’s social network and acquire support from people who have had a similar experience.