Seasonal and age-related changes in sperm quality of farmed arctic charr (Salvelinus alpinus).

BACKGROUND: Substantial variation in male fertility is regularly observed in farmed Arctic charr. However, detailed investigations of its fluctuation during a reproductive season and across years are lacking. Furthermore, information about the effect of underlying genetic factors influencing sperm quality is scarce. The current study focused on seasonal and age-related factors that may affect sperm quality characteristics in males reared in natural and delayed photoperiods. Animals were sampled three times for two consecutive years, and sperm quality parameters were recorded using a computer-assisted sperm analysis (CASA) system. Thereafter, high-throughput sequencing technologies were applied, aiming to identify genomic regions related to the variation of sperm quality throughout the reproductive season. RESULTS: An across-season variation in the recorded sperm quality parameters was evident. Overall, 29% and 42% of males from the natural and delayed spawning groups had a highly variable total progressive motility. Males at four years of age showed significantly higher sperm motility and velocities during the early October and November recordings compared to the following year when the same animals were five years of age. On the other hand, the opposite was observed regarding sperm concentration during the last sampling. A genome-wide FST scan detected SNP differentiation among males with high and low variability in total progressive motility (PM) on eight chromosomes (FST > 0.17), Genome wide windows with the highest FST contained SNPs in proximity (within 250 kb up- and downstream distance) to 16 genes with sperm quality biological functions in mammalian species. CONCLUSION: Our findings provide a detailed view of seasonal, age-related, and genetic effects on sperm quality and can be used to guide decisions on broodstock selection and hatchery management.

Interactions of the male contraceptive target EPPIN with semenogelin-1 and small organic ligands.

Novel male contraceptives will promote gender equality in sharing contraceptive responsibility. The sperm-associated protein epididymal protease inhibitor (EPPIN) is a promising target for non-hormonal male contraception. EPPIN interacts with the semen coagulum protein semenogelin-1 (SEMG1) on the sperm surface, leading to transient inhibition of sperm motility after ejaculation. Small organic molecules targeting EPPIN's SEMG1-binding are under development as male contraceptives. Here, we combined computational approaches to uncover key aspects underlying EPPIN binding to SEMG1 and small organic ligands. We generated a human EPPIN model showing a typical arrangement of the WFDC (Whey-acid four disulfide core)-type and Kunitz-type domains, connected by a hinge region. Determining the EPPIN model's intrinsic motion by molecular dynamics simulations and normal mode analysis revealed a conformation, presenting a binding pocket that accommodates SEMG1Glu229-Gln247, EP055, and EP012. EPPIN's residues Phe63 and Lys68 (WFDC domain), Asp71 (hinge region), and Asn113, Asn114, and Asn115 (Kunitz domain) were identified as hot spots for SEMG1, EP055, and EP012 binding. Moreover, hydrophobic and hydrophilic residues in the WFDC and Kunitz domains allow plasma membrane anchoring, orienting the EPPIN binding pocket to the solvent. Targeting EPPIN's essential residues for its biomolecular interactions may improve the rational design of EPPIN ligands as spermiostatic compounds.

Semen quality and sperm DNA fragmentation in cancer patients undergoing sperm cryopreservation.

PURPOSE: We compared semen quality and sperm DNA fragmentation in cancer patients who underwent sperm banking and controls who underwent sperm cryopreservation for assisted reproductive technology (ART). MATERIALS AND METHODS: A total of 132 men, 65 cancer patients and 67 controls, were prospectively enrolled and performed sperm cryopreservation for fertility preservation from May 2019 to February 2021. Sperm quality was determined by measuring semen volume, sperm concentration, sperm motility, and sperm DNA fragmentation index (DFI). Sperm quality and sperm DFI were compared in cancer patients and controls. RESULTS: The major cancers of the 65 cancer patients were leukemia (26.2%), testicular cancer (23.1%), and lymphoma (20.0%). Sperm concentration, sperm total motility, and sperm progressive motility were significantly lower in cancer patients than in controls. Sperm DFI was significantly higher in cancer patients than in controls (24.32%±15.69% vs. 19.11%±11.63%; p=0.033). After excluding 8 cancer patients who received chemotherapy before sperm banking, sperm concentration, sperm total motility, and sperm progressive motility were significantly lower in cancer patients than in controls, but there was no significant difference in sperm DFI for cancer patients and controls (23.14%±12.79% vs. 19.11%±11.63%; p=0.069). CONCLUSIONS: Sperm quality was lower in cancer patients than in controls. There was no difference in the sperm DFI of cancer patients prior to chemotherapy and men presenting for sperm cryopreservation for ART. We recommend that all men who are planning cancer therapy should be offered sperm banking prior to gonadotoxic chemotherapy as a standard of fertility preservation.

A CUG-initiated CATSPERθ functions in the CatSper channel assembly and serves as a checkpoint for flagellar trafficking.

Calcium signaling is critical for successful fertilization. In spermatozoa, calcium influx into the sperm flagella mediated by the sperm-specific CatSper calcium channel is necessary for hyperactivated motility and male fertility. CatSper is a macromolecular complex and is repeatedly arranged in zigzag rows within four linear nanodomains along the sperm flagella. Here, we report that the Tmem249-encoded transmembrane (TM) domain-containing protein, CATSPERθ is essential for the CatSper channel assembly during sperm tail formation. CATSPERθ facilitates the channel assembly by serving as a scaffold for a pore-forming subunit CATSPER4. CATSPERθ is specifically localized at the interface of a CatSper dimer and can self-interact, suggesting its potential role in CatSper dimer formation. Male mice lacking CATSPERθ are infertile because the sperm lack the entire CatSper channel from sperm flagella, rendering sperm unable to hyperactivate, regardless of their normal expression in the testis. In contrast, genetic abrogation of any of the other CatSper TM subunits results in loss of CATSPERθ protein in the spermatid cells during spermatogenesis. CATSPERθ might act as a checkpoint for the properly assembled CatSper channel complex to traffic to sperm flagella. This study provides insights into the CatSper channel assembly and elucidates the physiological role of CATSPERθ in sperm motility and male fertility.

Sperm motility assessed by deep convolutional neural networks into WHO categories.

Semen analysis is central in infertility investigation. Manual assessment of sperm motility according to the WHO recommendations is the golden standard, and extensive training is a requirement for accurate and reproducible results. Deep convolutional neural networks (DCNN) are especially suitable for image classification. In this study, we evaluated the performance of the DCNN ResNet-50 in predicting the proportion of sperm in the WHO motility categories. Two models were evaluated using tenfold cross-validation with 65 video recordings of wet semen preparations from an external quality assessment programme for semen analysis. The corresponding manually assessed data was obtained from several of the reference laboratories, and the mean values were used for training of the DCNN models. One model was trained to predict the three categories progressive motility, non-progressive motility, and immotile spermatozoa. Another model was used in predicting four categories, where progressive motility was differentiated into rapid and slow. The resulting average mean absolute error (MAE) was 0.05 and 0.07, and the average ZeroR baseline was 0.09 and 0.10 for the three-category and the four-category model, respectively. Manual and DCNN-predicted motility was compared by Pearson's correlation coefficient and by difference plots. The strongest correlation between the mean manually assessed values and DCNN-predicted motility was observed for % progressively motile spermatozoa (Pearson's r = 0.88, p < 0.001) and % immotile spermatozoa (r = 0.89, p < 0.001). For rapid progressive motility, the correlation was moderate (Pearson's r = 0.673, p < 0.001). The median difference between manual and predicted progressive motility was 0 and 2 for immotile spermatozoa. The largest bias was observed at high and low percentages of progressive and immotile spermatozoa. The DCNN-predicted value was within the range of the interlaboratory variation of the results for most of the samples. In conclusion, DCNN models were able to predict the proportion of spermatozoa into the WHO motility categories with significantly lower error than the baseline. The best correlation between the manual and the DCNN-predicted motility values was found for the categories progressive and immotile. Of note, there was considerable variation between the mean motility values obtained for each category by the reference laboratories, especially for rapid progressive motility, which impacts the training of the DCNN models.

Obesity is associated with quality of sperm parameters in men with infertility: a cross-sectional study.

BACKGROUND: Previous studies examined the effects of obesity on sperm parameters and reported inconsistent results. Thus, the present study aimed to evaluate the association between obesity and the quality of sperm parameters in infertile men. MATERIAL AND METHODS: The present cross-sectional study evaluated 218 infertile men aged 20-50. To this end, the 168-item food frequency questionnaire (FFQ) was utilized to evaluate dietary intake. The anthropometric and biochemical variables were examined using standard methods. Further, the association between obesity and the quality of sperm parameters was evaluated using the controlled linear regression for potential confounders. RESULTS: The normal sperm morphology had a significant inverse association with BMI [adjusted ß - 0.074, CI (- 0.141 to - 0.008), P = 0.029] and WC [adjusted ß - 0.026, CI (- 0.051 to - 0.001), P = 0.038]. Additionally, visceral fat had a marginal inverse association with normal sperm morphology [adjusted ß - 0.065, CI (- 0.138 to 0.008), P = 0.079] and non-progressive sperm motility [adjusted ß - 0.241, CI (- 0.495 to 0.014), P = 0.063]. CONCLUSION: Even though the present results indicated that obesity, abdominal obesity, and visceral fat had inverse associations with normal sperm morphology, more mechanism-based studies should be conducted to confirm these findings.

Treatment with cholesterol just after thawing maintains the fertility of bull sperm.

Freezing and thawing diminish sperm motility and fertility by disrupting the cholesterol balance in sperm plasma and organelle membranes. The aim of this study was to elucidate the mechanisms through which exogeneous cholesterol treatment enhances the quality of frozen-thawed bull sperm. The incorporation of cholesterol was investigated using boron-dipyrromethene (BODIPY)-cholesterol, and BODIPY signals were detected not only in the plasma membrane but also in the midpiece region immediately after thawing. The positive signal of cholesterol in the midpiece region was inhibited by a scavenger receptor class B Type I (SR-BI) inhibitor, block lipid transport 1 (BLT-1). To comprehend the role of exogenous cholesterol in the functions of the plasma membrane, propidium iodide (PI)/Annexin V and peanut agglutinin lectin (PNA) staining were performed. The results showed that treatment with exogenous cholesterol increased the number of acrosome-intact sperm and decreased the number of sperm with damage to the plasma membrane. Moreover, since BODIPY signals were also observed in the midpiece region, mitochondrial function was evaluated using a flux analyzer and a flow cytometer with 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolyl carbocyanine iodide (JC-1) staining, revealing an increase in the number of sperm with high-mitochondrial activity and oxygen consumption. Finally, to assess sperm fertility, computer-assisted sperm analysis (CASA) and IVF were carried out. Sperm velocities and fertilization rates in IVF were significantly enhanced by the addition of cholesterol just after thawing. Thus, the treatment with cholesterol after thawing protected the plasma membrane from the stress of thawing and maintained mitochondrial function, thereby preserving the fertilization ability of frozen-thawed bull sperm for conventional IVF and artificial insemination (AI). Therefore, the application of cholesterol just after thawing is a promising option for improving the fertility of frozen-thawed sperm.

Effects of hyperthyroidism and diabetes mellitus on spermatogenesis in peri- and post-pubertal mice.

Introduction: Diabetes and thyroid dysfunction often co-exist. One autoimmune disorder always invites another and it has been reported that such co-morbid ailments always become detrimental to the health of the patients. Materials and methods: In our previous work, we elucidated the interactions of diabetes and hypothyroidism on testicular development and spermatogenesis. However, the present study illuminates the interface between diabetes and hyperthyroidism, where 16 ICR pregnant primiparous mice were used and subsequently 48 male pups were randomly selected (n=12/group) and separated into 4 groups: control (C), diabetic (D), diabetic + hyperthyroidism (DH) and hyperthyroidism (H). Results: Computerized sperm analyses showed significant reductions in count by 20% and increases of 15% in D and H animals, respectively, vs. controls. However, rapid progressive sperm motility was significantly lower only in D (30%) compared with C mice. Our histomorphometric investigation depicted damaging effects on testicular and epididymal tissues; the stroma adjacent to the seminiferous tubules of the D mice revealed edematous fluid and unstructured material. However, in the epididymis, germ cell diminution contraction of tubules, compacted principal and clear cells, lipid vacuolization, atypical cellular connections, exfoliated epithelial cells, and round spermatids were conspicuous in DH mice. Discussion: Collectively, our experiment was undertaken to ultimately better recognize male reproductive disorders in diabetic-hyperthyroid patients.

Control of intracellular pH and bicarbonate by CO2 diffusion into human sperm.

The reaction of CO2 with H2O to form bicarbonate (HCO3-) and H+ controls sperm motility and fertilization via HCO3--stimulated cAMP synthesis. A complex network of signaling proteins participates in this reaction. Here, we identify key players that regulate intracellular pH (pHi) and HCO3- in human sperm by quantitative mass spectrometry (MS) and kinetic patch-clamp fluorometry. The resting pHi is set by amiloride-sensitive Na+/H+ exchange. The sperm-specific putative Na+/H+ exchanger SLC9C1, unlike its sea urchin homologue, is not gated by voltage or cAMP. Transporters and channels implied in HCO3- transport are not detected, and may be present at copy numbers < 10 molecules/sperm cell. Instead, HCO3- is produced by diffusion of CO2 into cells and readjustment of the CO2/HCO3-/H+ equilibrium. The proton channel Hv1 may serve as a unidirectional valve that blunts the acidification ensuing from HCO3- synthesis. This work provides a new framework for the study of male infertility.

Identification of Male Sex-Related Genes Regulated by SDHB in Macrobrachium nipponense Based on Transcriptome Analysis after an RNAi Knockdown.

The oriental river prawn (Macrobrachium nipponense) is a commercially important species in Asia. A previous study showed that the succinate dehydrogenase complex iron sulfur subunit B (SDHB) gene participates in testes development in this species through its effect on the expression of the insulin-like androgenic gland hormone gene. This study knocked-down the Mn-SDHB genes in M. nipponense using RNAi. A transcriptome analysis of the androgenic gland and testes was then performed to discover the male sex-related genes regulated by SDHB and investigate the mechanism of male sexual development in this species. More than 16,623 unigenes were discovered in each sample generated. In the androgenic gland, most of the differentially expressed genes were enriched in the hypertrophic cardiomyopathy pathway, while in the testes, they were enriched in the citrate cycle pathway. In addition, after Mn-SDHB knockdown, five genes were found to be downregulated in the androgenic gland in a series of biological processes associated with phosphorylated carbohydrate synthesis and transformations in the glycolysis/gluconeogenesis pathway. Moreover, a total of nine male sex-related genes were identified including Pro-resilin, insulin-like androgenic gland hormone, Protein mono-ADP-ribosyltransferase PAPR11, DNAJC2, C-type Lectin-1, Tyrosine-protein kinase Yes, Vigilin, and Sperm motility kinase Y-like, demonstrating the regulatory effects of Mn-SDHB, and providing a reference for the further study of the mechanisms of male development in M. nipponense.

Effects of in vitro repaglinide supplementation on improving sperm motility parameters, viability, and DNA integrity in normozoospermic and asthenozoospermic men.

OBJECTIVE: Human sperm motility and hyperactivation (HA) are induced by different factors such as intracellular calcium concentration. Repaglinide is an antidiabetic drug that, via the blocking of ATP-sensitive potassium channels (K-ATP channels), depolarization of the ß-cell membrane, and opening of the voltage-gated calcium channels leads to an increase in intracellular calcium. The present study aimed to examine the effects of repaglinide on in vitro sperm motility parameters, viability, and DNA integrity in normozoospermic and asthenozoospermic men. METHODS: Semen samples were collected from two groups of normozoospermic donors and asthenozoospermic patients. The samples were washed free of seminal plasma and then treated with medium alone (control) or with 100 nM and 1µM concentrations of repaglinide. After 1 h of incubation, percent sperm motility and hyperactivation were assessed; after 2 h of incubation, sperm viability and DNA fragmentation rate were evaluated by the Eosin-Y and acridine orange staining, respectively. RESULTS: In both groups, repaglinide at a concentration of 100 nM and 1µM significantly improved percent sperm motility, hyperactivation, and vital sperms with normal DNA; in specimens from normozoospermic men, the 1µM concentration had a noticeable effect on progressive motility; in samples from asthenozoospermic men, the highest hyperactivation rate was seen at a concentration of 100 nM as compared with the 1µM concentration and controls (p<0.05). CONCLUSIONS: Our results suggest that repaglinide can improve sperm motility, hyperactivity, viability, and DNA integrity in both normozoospermic and asthenozoospermic men.

Short-interval second ejaculation improves sperm quality, blastocyst formation in oligoasthenozoospermic males in ICSI cycles: a time-lapse sibling oocytes study.

Background: Does short-interval second ejaculation improve sperm quality, embryo development and clinical outcomes for oligoasthenozoospermia males received intracytoplasmic sperm injection (ICSI) treatment? Methods: All enrolled male patients underwent short-interval secondary ejaculation on the day of oocyte retrieval, and 786 sibling MII oocytes from 67 cycles were equally divided into two groups based on whether the injected spermatozoons originated from the first or second ejaculation. Semen parameters, embryo development efficiency, morphokinetic parameters and clinical outcomes were compared between the two groups to assess the efficiency and clinical value of short-interval second ejaculation in ICSI cycles. Results: Short-interval second ejaculation significantly improved sperm motility, normal morphological rate, and sperm DNA integrity both before and after sperm swim-up. The high-quality blastocyst rate (24.79% versus 14.67%), available blastocyst rate (57.56% versus 48.44%), and oocyte utilization rate (52.93% versus 45.29%) were significantly higher in the second ejaculation group (P<0.05). The clinical pregnancy rate (59.09% versus 47.37%), implantation rate (42.11% versus 32.35%) and live birth rate (40.91% versus 31.58%) were higher in the second ejaculation group, but the differences were not significant (P>0.05). Time-lapse analysis showed that morphokinetic time points after the 7-cell stage were earlier in the second ejaculation group but without a significant difference (P>0.05), and abnormal embryo cleavage patterns between the two groups were not significantly different (P>0.05). Conclusions: Short-interval second ejaculation significantly improves sperm quality in oligoasthenozoospermic males, and is beneficial for blastocyst formation efficiency in ICSI cycles. This study suggested a non-invasive and simple but effective strategy for improving ICSI treatment outcomes.

Leptin Receptor Gln223Arg Polymorphism of Human Spermatozoa Associated with Male Infertility in a Chinese Population.

Background: Leptin (LEP) is believed to play a crucial role in male reproduction, while the molecular mechanisms through which LEP affects the male reproductive system are unclear. LEP acts by binding to a leptin receptor (LEPR) which mediates its physiological action, but there are only limited studies on the function of LEPR in human sperm. Purpose: This study aimed to determine the Gln223Arg polymorphisms of the LEPR gene in human spermatozoa and evaluate their possible relationship with semen variables. Methods: The study was performed on Chinese men: 115 healthy subjects and 108 patients with primary and 98 with secondary infertility. Semen samples were obtained from all patients, and semen variables were analyzed. The genotypic and allelic frequencies of Gln223Arg polymorphism in spermatozoa were determined by PCR and restriction fragment length polymorphism (RFLP) analyses. Statistical analyses were performed using the chi-square test, the Kruskal-Wallis test, and the Mann-Whitney test. Results: There were no significant differences in genotypic or allelic frequency distributions of Gln223Arg polymorphism among men with primary infertility, secondary infertility, and controls. Similarly, semen volume and sperm concentration did not differ with the different genotypes in all groups of men. The percentages of motile sperm for AA + AG genotypes in men with primary infertility (31.98%) were significantly lower than those in secondary infertility, and control men with GG genotypes were 34.41% and 59.36%, respectively. At the same time, the percentages of normal morphology sperm for AA + AG genotypes in men with primary infertility (2.93%) were significantly lower than those in secondary infertility and control men with GG genotypes 3.71% and 6.54%, respectively. Conclusion: This study reveals a possible association between the Gln223Arg polymorphism of the LEPR gene in spermatozoa affecting spermatozoal membrane integrity and having a direct role in sperm motility.

Exposure to parabens and semen quality in reproductive-aged men.

BACKGROUND: Parabens are common preservatives in personal care products, cosmetics, and medical goods. In the past few years, animal studies showed the male reproductive toxicity associated with some parabens. Yet, epidemiological studies have generated inconsistent findings and research rarely has focused on the mixture effects of the parabens. We aimed to explore the associations between individual paraben exposure as well as the mixture and semen quality parameters. METHODS: A total of 795 male partners from preconception couples were included in the study. Their urine samples were analyzed for the concentrations of six parabens, namely methyl paraben (MeP), ethyl paraben (EtP), propyl paraben (PrP), butyl paraben (BuP), benzyl paraben (BzP) and heptyl paraben (HeP). Multiple linear regression models and weighted quantile sum regression (WQS) models were utilized to assess the relationships between individual paraben exposure and paraben mixture with semen quality parameters, respectively. RESULTS: After adjusting for covariates, exposure to a paraben mixture was significantly associated with declining sperm concentration, total sperm count, and progressive motility, among which BuP was identified as the main contributor to sperm concentration and total sperm count while MeP to progressive motility. Results from multiple linear regression models were generally in line with the WQS analysis. CONCLUSIONS: Our results suggest negative associations between paraben mixture and sperm concentration, total sperm count, and sperm motility among reproductive-aged men.

Association of living environmental and occupational factors with semen quality in chinese men: a cross-sectional study.

Sperm quality can be easily influenced by living environmental and occupational factors. This study aimed to discover potential semen quality related living environmental and occupational factors, expand knowledge of risk factors for semen quality, strengthen men's awareness of protecting their own fertility and assist the clinicians to judge the patient's fertility. 465 men without obese or underweight (18.5 < BMI < 28.5 kg/m2), long-term medical history and history of drug use, were recruited between June 2020 to July 2021, they are in reproductive age (25 < age < 45 years). We have collected their semen analysis results and clinical information. Logistic regression was applied to evaluate the association of semen quality with different factors. We found that living environment close to high voltage line (283.4 × 106/ml vs 219.8 × 106/ml, Cohen d = 0.116, P = 0.030) and substation (309.1 × 106/ml vs 222.4 × 106/ml, Cohen d = 0.085, P = 0.015) will influence sperm count. Experienced decoration in the past 6 months was a significant factor to sperm count (194.2 × 106/ml vs 261.0 × 106/ml, Cohen d = 0.120, P = 0.025). Living close to chemical plant will affect semen PH (7.5 vs 7.2, Cohen d = 0.181, P = 0.001). Domicile close to a power distribution room will affect progressive sperm motility (37.0% vs 34.0%, F = 4.773, Cohen d = 0.033, P = 0.030). Using computers will affect both progressive motility sperm (36.0% vs 28.1%, t = 2.762, Cohen d = 0.033, P = 0.006) and sperm total motility (57.0% vs 41.0%, Cohen d = 0.178, P = 0.009). After adjust for potential confounding factors (age and BMI), our regression model reveals that living close to high voltage line is a risk factor for sperm concentration (Adjusted OR 4.03, 95% CI 1.15-14.18, R2 = 0.048, P = 0.030), living close to Chemical plants is a protective factor for sperm concentration (Adjusted OR 0.15, 95% CI 0.05-0.46, R2 = 0.048, P = 0.001) and total sperm count (Adjusted OR 0.36, 95% CI 0.13-0.99, R2 = 0.026, P = 0.049). Time spends on computer will affect sperm total motility (Adjusted OR 2.29, 95% CI 1.11-4.73, R2 = 0.041, P = 0.025). Sum up, our results suggested that computer using, living and working surroundings (voltage line, substation and chemical plants, transformer room), and housing decoration may association with low semen quality. Suggesting that some easily ignored factors may affect male reproductive ability. Couples trying to become pregnant should try to avoid exposure to associated risk factors. The specific mechanism of risk factors affecting male reproductive ability remains to be elucidated.

Effects of Alcohol Use on Sperm Chromatin Structure.

INTRODUCTION: The evaluation of the infertile couple is often complex as multiple factors in both the male and female can contribute, including social history. Previous studies have displayed that male ethanol consumption can disturb sperm motility, nuclear maturity, and DNA integrity, likely resulting in infertility. A previous study primarily looking at vitamin D levels and sperm parameters incidentally demonstrated increased high DNA stainability (HDS), which correlates with immaturity of the sperm nucleus, in males who do not use alcohol. The main purpose of this study is to evaluate the effects of male alcohol use on sperm chromatin structure analysis (SCSA), including DNA fragmentation and HDS. METHODS: This study was a retrospective chart review of 210 consecutive couples that presented to a midsize infertility clinic in the Midwest and had a semen analysis and SCSA performed. Data were extracted from the electronic medical record, de-identified, and independently entered into an Excel spreadsheet by two investigators. The spreadsheets were electronically compared, and discrepancies resolved by reference to the EMR primary data. Data extracted included demographics, tobacco use, alcohol use, occupational exposures, semen analysis results, and SCSA results (DNA fragmentation index (DFI) and HDS. Statistical analysis (regression) was performed on this data set to determine significance with a p-level of 0.05, with primary input being level of alcohol use and outcome being the SCSA parameters. RESULTS: 11% of the cohort had heavy alcohol use (greater tyhan 10 drinks/week), 27% moderate (3-10/week), 34% rare (0.5-3/ week), and 28% no alcohol use. 36% of the cohort had HDS greater than 10% (a marker of immaturity of sperm chromatin). Level of alcohol use was not significantly associated with HDS greater than 10% (p=0.55). Average total DFI was 12.99% (greater than 25% is associated with poorer fertility). Total DFI was not significantly associated with the level of alcohol use (p=0.7). Heavy alcohol use was significantly associated with lower sperm density (p=0.042). Increasing age was significantly associated with increasing DFI (p=0.006), increased sperm density (p=0.002) and lower semen volume (p=0.022). Exposure to heat at work was significantly associated with lower semen volume (p=0.042). Tobacco use was associated with lower sperm motility and lower sperm density (p=0.002). CONCLUSIONS: There was not a significant association between the level of alcohol use (heavy, moderate, rare, or none) and the HDS or DFI of sperm. The overall literature remains equivocal with respect to alcohol's effect on sperm chromatin structure. Heavy alcohol use was associated with lower sperm motility. Alcohol may exert a negative effect on semen parameters via disruption of the testosterone hormonal axis, through direct toxicity to Leydig and/or Sertoli cells, and/or through oxidative damage to sperm DNA. The overall effect on fertility and the possibility of transgenerational effects through DNA damage both require further characterization. Increasing age was associated with poorer sperm parameters as expected. Heat exposure was associated with lower semen volume and tobacco use was associated with lower sperm motility and density.

Transcriptomic analysis of mechanism underlying the effect of induced molting on semen quality and reproductive performance in aged Houdan roosters.

The reproductive performance of breeder roosters has significant economic importance in the poultry industry. Breeder roosters have severely reduced semen quality with age and will be at risk of culling in the following years. In order to extend the use of breeder roosters, we drew on the induced molting model of hens and selected 35 Houdan roosters aged 50 wk for induced molting. By comparing the body weight, testicular weight, semen quality, and reproductive performance before and after induced molting, we found that induced molting could restore the body weight and testicular weight to the levels before molting (P > 0.05). At the same time, it significantly improved sperm motility (P < 0.05) and also improved reproductive performance such as fertilization rate and hatching rate. To further reveal the mechanism underlying the effects of induced molting on semen quality and reproductive performance in aged Houdan roosters, we collected testes from 3 periods: 1 d before fasting (F0), 15 d after fasting (F15), and 32 d after recovery feeding (R32) for transcriptome sequencing analysis. A total of 5,671 genes were detected in F0, F15, and R32, and trend analysis of the 5,671 differential genes showed 2 significant trends (profile 5 and profile 2). KEGG enrichment analysis of the genes in the 2 profiles, revealed significantly enriched pathway regulation of actin cytoskeleton. In the regulation of actin cytoskeleton pathway, we found a protein kinase gene (SRC) and a senescence gene (ROCK2). SRC was highly expressed at F15, leading to the phosphorylation of key substrates, which in turn disrupted the Sertoli cell spermatid connection and the spermiogenesis process, resulting in no mature spermatozoa produced from F15, SRC expression was inhibited at R32, the expression level was reduced, and mature spermatozoa reappeared. The senescence gene ROCK2 was highly expressed at F15 compared to F0 and R32, which may have been responsible for inducing senescence atrophy in the testes.

Effect of season on the dynamics of cat sperm DNA fragmentation.

BACKGROUND: Feline species undergo reproductive seasonality; thus, sperm characteristics, such as DNA integrity, can be affected by the photoperiod. This study was conducted to determine the effect of seasonal changes on sperm quality and on the dynamics of sperm DNA fragmentation. Epididymal spermatozoa were collected from 36 tomcats subjected to bilateral orchiectomy during breeding (BS) and non-breeding (NBS) seasons. Sperm samples were obtained by cutting the cauda epididymis and assessed for sperm motility, concentration, acrosome integrity, plasma membrane integrity and sperm morphology. Sperm DNA fragmentation was evaluated by the sperm chromatin dispersion test after 0, 6, and 24 h of incubation at 37 °C. RESULTS: The total sperm motility and plasma membrane integrity values were greater during the BS, while the percentages of abnormal sperm and head defects were lesser (p < 0.05). No significant differences in DNA fragmentation were found between seasons after sperm collection. DNA damage was greater after 24 h of incubation at 37 °C in both seasons, although the percentage of spermatozoa with fragmented DNA was significantly lesser in the BS than in the NBS at 24 h (p < 0.05). CONCLUSIONS: The study suggests seasonal changes in some of the quality parameters of cat sperm. DNA fragmentation dynamics were affected by the time of incubation and reproductive season; therefore, this technique might be used as an additional tool to test the potential fertility of semen samples used in feline-assisted reproduction.

GGA1 participates in spermatogenesis in mice under stress.

Background: Infertility is recognized as a common and worrisome problem of human reproduction worldwide. Based on previous studies, male factors account for about half of all infertility cases. Exposure to environmental toxicants is an important contributor to male infertility. Bisphenol A (BPA) is the most prominent toxic environmental contaminant worldwide affecting the male reproductive system. BPA can impair the function of the Golgi apparatus which is important in spermatogenesis. GGA1 is known as Golgi-localized, gamma adaptin ear-containing, ARF-binding protein 1. Previously, it has been shown that GGA1 is associated with spermatogenesis in Drosophila, however, its function in mammalian spermatogenesis remains unclear. Methods: Gga1 knockout mice were generated using the CRISPR/Cas9 system. Gga1-/- male mice and wild-type littermates received intraperitoneal (i.p.) injections of BPA (40 µg/kg) once daily for 2 weeks. Histological and immunofluorescence staining were performed to analyze the phenotypes of these mice. Results: Male mice lacking Gga1 had normal fertility without any obvious defects in spermatogenesis, sperm count and sperm morphology. Gga1 ablation led to infertility in male mice exposed to BPA, along with a significant reduction in sperm count, sperm motility and the percentage of normal sperm. Histological analysis of the seminiferous epithelium showed that spermatogenesis was severely disorganized, while apoptotic germ cells were significantly increased in the Gga1 null mice exposed to BPA. Our findings suggest that Gga1 protects spermatogenesis against damage induced by environmental pollutants.

Maternal restricted- and over- feeding during gestation perturb offspring sperm epigenome in sheep.

In brief: Inadequate maternal nutrition during gestation can have immediate and lifelong effects on offspring. This study shows that maternal restricted - and over- nutrition during gestation do not affect semen characteristics in F1 male offspring but alters offspring sperm sncRNA profiles and DNA methylome in sheep. Abstract: There is a growing body of evidence that inadequate maternal nutrition during gestation can have immediate and lifelong effects on offspring. However, little is known about the effects of maternal nutrition during gestation on male offspring reproduction. Here, using a sheep model of maternal restricted - and over - nutrition (60 or 140% of the National Research Council requirements) during gestation, we found that maternal restricted - and over - nutrition do not affect semen characteristics (i.e. volume, sperm concentration, pH, sperm motility, sperm morphology) or scrotal circumference in male F1 offspring. However, using small RNA sequencing analysis, we demonstrated that both restricted - and over - nutrition during gestation induced marked changes in composition and expression of sperm small noncoding RNAs (sncRNAs) subpopulations including in male F1 offspring. Whole-genome bisulfite sequencing analysis further identified specific genomic loci where poor maternal nutrition resulted in alterations in DNA methylation. These findings indicate that maternal restricted - and over - nutrition during gestation induce epigenetic modifications in sperm of F1 offspring sperm in sheep, which may contribute to environmentally influenced phenotypes in ruminants.