Sperm Motility Research Articles

Association of NOX5 Expression with Sperm Activity and Motility in Pathospermic Infertile Men

Background: The newest NOX isoform, NOX5, has been found in mammalian spermatozoa. Many physiological and pathological situations in spermatozoa are mediated by reactive oxygen species (ROS). NOX5 is the main source of ROS in spermatozoa. Our purpose was to investigate the changes in NOX5 expression and the effect of NOX5 expression on sperm motility, chromatin integrity, and oxidative status in oligoasthenozoospermic compared to normozoospermic men. Methods: Semen samples were collected from 30 normozoospermic (NS) and 30 oligoasthenozoospermic (OAS) men. NOX5 protein expression in sperm samples was evaluated by immunohistochemistry and western blot. Oxidative stress status was evaluated by total antioxidant capacity (TAC), total oxidant capacity (TOC), and oxidative stress index (OSI) parameters. Chromatin integrity in spermatozoa was evaluated by toluidine blue staining. Results: NOX5 expression levels were significantly higher in OAS group than in NS group (p<0.001). In addition, chromatin integrity was significantly higher in the OAS group in comparison to NS group (p<0.001). TAC levels were higher in the NS group, but OSI and TOC levels were significantly higher in OAS group (p<0.001). It was found that NOX5 protein expression was positively correlated with oxidative stress and chromatin integrity and negatively correlated with motility (p<0.01). Conclusion: These results suggest that overexpression of NOX5 may be the source of excessive ROS production and oxidative stress injuries in oligoasthenozoospermic men. Considering that NOX5 expression is positively correlated with oxidative stress and chromatin integrity but negatively correlated with motility, it can be considered a biomarker to be used in assisted reproductive procedures.

The Impact of NADPH Oxidase 5 Activity and Reactive Oxygen Species on Ca-pacitated Human Sperm

Background: Progesterone (P4) activates sperm calcium channels (CatSper), allowing calcium to enter the cell, which activates NADPH Oxidase-5 (NOX5) and produces reactive oxygen species (ROS). While calcium and ROS are essential for sperm capacitation, the role of NOX5 in capacitated sperm is unclear. This study investigated NOX5 activity in capacitated human sperm. Methods: Forty semen samples from fertile men were processed, with motile sperm separated and divided into nine groups: control (Ham's F-10), solvent (DMSO), progesterone, diphenyleneiodonium chloride (DPI, NOX5 inhibitor), phorbol-12-my-ristate 13-acetate (PMA, NOX5 activator), P4+DPI, P4+PMA, Trolox, and P4+ Trolox. Sperm kinematics, membrane integrity, survival rate, and ROS production was evaluated. Data were analyzed using ANOVA and Kruskal-Wallis tests, p£ 0.05 considered statistically significant. Results: Progressive motility significantly decreased with DPI (56.2±2.1%) and PMA (56.5±2.1%), both alone and combined with progesterone (58.0±2.0% and 57.4±2.2%), compared to the progesterone group (66.0±1.9%). No significant change was observed in the Trolox groups. Progesterone, alone or combined with DPI, PMA, and Trolox, significantly reduced sperm linearity from 0.6±0.01 to 0.5± 0.01%. Straight-line velocity decreased in P4+PMA and P4+Trolox groups (88.2± 4.4 and 89.7±3.9 μm/s) compared to the control group (105.0±5.5 μm/s). Trolox reduced ROS content, while other treatments had no effect on ROS levels. Conclusion: NOX5 does not play a prominent role in capacitated sperm. The negative effects of PMA and DPI on sperm motility appear independent of their actions on NOX5 and ROS production. Trolox did not affect sperm motility and survival, indicating that capacitated sperm require little or no ROS.

EP300‐interacting inhibitor of differentiation 3 is required for spermatogenesis in mice

AbstractBackgroundMammalian spermatogenesis is a highly complex process of cell proliferation, meiosis, and differentiation. A series of genes are expressed in an orderly and precise manner to ensure spermatogenesis, with chromatin undergoing intricate changes throughout. EP300‐interacting inhibitor of differentiation 3 (Eid3) is a testis‐enriched gene, but its role in male reproduction remains unclear.ObjectiveTo investigate the role of EID3 in male spermatogenesis and explore the potential underlying mechanism.Materials and MethodsWe generated Eid3 knockout mouse model using the CRISPR‐Cas9 system. We measured the expression of EID3 in mouse tissues and testicular cell populations by qRT‐PCR and western blot. Histological analysis, including hematoxylin and eosin (H&E) and periodic acid‐Schiff (PAS) staining, together with computer‐assisted sperm analysis (CASA), were performed to evaluate the effect of EID3 on spermatogenesis in mice. Light and ultrastructural microscopy were used to evaluate the morphology and structure of the Eid3−/− spermatozoa. We used western blot and immunofluorescence to further analyze the function of EID3 in spermiogenesis.ResultsEid3−/− mouse showed a significant decrease in sperm count, motility, and morphology. Loss of EID3 impaired the normal meiotic process and induced apoptosis of abnormally developing spermatocytes, ultimately resulting in the decrease of sperm cell number. Additionally, EID3 deficiency led to a decrease in histone acetylation levels in spermatids, impaired histone‐to‐protamine transition and chromatin condensation process, and ultimately resulted in abnormal sperm morphology.Discussion and ConclusionsThis study confirms for the first time that EID3 is crucial for meiosis and chromatin condensation during spermatogenesis, and EID3 deficiency leads to a significant decrease in sperm parameters. Given the high expression paradigm of Eid3 in human testis, EID3 likely plays a role in human reproduction. Future research could provide a new target for the clinical diagnosis and treatment of male infertility.

The Protective Effects of Citrulline on Testicular Injury Induced by Torsion and Detorsion in Adult Male Rats: An Experimental Study

Background: Testicular torsion is a critical urological emergency that can lead to testicular ischemia and significant tissue damage. Citrulline, a supplement known for enhancing cellular metabolism and mitigating oxidative stress and inflammation, has been explored for its protective effects against testicular injury resulting from torsion and detorsion in rat models. Methods: This study involved 42 Wistar rats, divided into six groups: Sham, torsion/detorsion (T/D), and four groups receiving varying doses of Citrulline (300, 600, 900 mg/kg) and vitamin E (20 mg/kg). A surgical procedure was performed to induce torsion by rotating the left testicle for 4 hr, followed by reperfusion. Daily oral administration of the supplements continued for one week post-surgery. Assessments included oxidative stress markers, apoptosis, inflammation, pathology, and sperm parameters. Statistical analysis was conducted using GraphPad Prism. Results: Citrulline administration at doses of 600 and 900 mg/kg significantly reduced malondialdehyde (MDA) and reactive oxygen species (ROS) levels. Additionally, it increased glutathione (GSH) levels and decreased protein carbonyl levels at the 900 mg/kg dose. The expression of interleukin-6 (IL-6) decreased at 900 mg/ kg, tumor necrosis factor-alpha (TNF-α) levels dropped at 600 and 900 mg/kg, and the pro-apoptotic factor Bax was reduced at all doses. Sperm analysis showed improved sperm count and motility at the 900 mg/kg dose. Histological examination revealed significant positive effects of Citrulline on testicular tissue. Conclusion: Citrulline effectively lowers oxidative stress, inflammation, while enhancing sperm quality and pathological outcomes. These results indicate that Citrulline has potential as a therapeutic agent for testicular torsion.

Impact of adalimumab on erectile dysfunction, sperm parameters and hormonal profile in male psoriasis patients: a six-month observational study.

Psoriasis, a chronic inflammatory skin disease, is associated with systemic complications that extend beyond cutaneous lesions, including cardiovascular risks and sexual dysfunction. Erectile dysfunction (ED) is notably more prevalent in male psoriasis patients, likely driven by both systemic inflammation and psychological stress. Adalimumab (ADA), a tumor necrosis factor-alpha (TNF-α) inhibitor, has been shown to effectively reduce psoriasis severity, but its effects on sexual and reproductive health remain underexplored. This study investigates the impact of ADA on erectile function, sperm parameters, and hormonal profiles in male psoriasis patients. This six-month prospective observational study included 33 biologic-naïve male patients aged 18-50 years with moderate-to-severe plaque psoriasis (Psoriasis Area and Severity Index [PASI] > 10). Patients received ADA according to standard clinical protocols. Erectile function was assessed using the International Index of Erectile Function (IIEF-5). Sperm parameters, including ejaculate volume, sperm concentration, total sperm count, motility, vitality, and morphology, were analyzed following World Health Organization (WHO) 2010 criteria. Hormonal profiles (testosterone, luteinizing hormone (LH), follicle-stimulating hormone (FSH), estradiol, and prolactin) were measured via standardized assays. Statistical analyses were performed using paired t-tests or Wilcoxon signed-rank tests, with p-values < 0.05 considered significant. ADA significantly improved erectile function, as the mean IIEF-5 score increased from 21.3 ± 2.2 to 22.2 ± 1.9 (p = 0.03). The percentage of patients with ED decreased from 51.5% at baseline to 36.4% post-treatment (p < 0.001). Progressive sperm motility and vitality showed statistically significant improvement post-treatment (p = 0.02 and p = 0.04, respectively), while other sperm parameters remained unchanged. Total testosterone levels significantly increased from 3.4 ± 0.4 ng/ml to 3.5 ± 0.4 ng/ml (p = 0.02), while LH, FSH, estradiol, and prolactin levels showed no significant changes. The anti-inflammatory properties of adalimumab, through the inhibition of TNF-α, not only reduce psoriasis severity but also appear to exert positive effects on male sexual and reproductive health. Our study demonstrated significant improvements in erectile function, sperm motility, vitality, and testosterone levels in male psoriasis patients after adalimumab therapy. These findings suggest that beyond its role in controlling psoriatic skin lesions, adalimumab may help mitigate the systemic inflammatory burden that contributes to sexual dysfunction and impaired spermatogenesis. Future long-term studies are essential to further explore the sustained impact of TNF-α inhibition on male fertility and reproductive outcomes.

Ameliorative impacts of carvacrol on DNA integrity, oxidative stress, and sperm quality in asthenozoospermic infertile individuals during cryopreservation.

Nowadays, the cryopreservation process can produce reactive oxygen species (ROS), which cause damage to the motility, cell membrane, and DNA integrity of sperm. This study is aimed at evaluating the impact of carvacrol, as a powerful antioxidant, on sperm features and improving oxidative stress throughout the cryopreservation procedure. In this prospective study, semen samples from 25 patients with asthenozoospermia were separated into three groups: fresh, freezing, and freezing + carvacrol (a dose of 100µM). The subsequent parameters were evaluated using standard methods in all three groups: sperm motility according to WHO criteria, sperm morphology using Papanicolaou staining, sperm viability with eosin-nigrosin staining, DNA integrity with acridine orange staining, levels of antioxidant enzymes (catalase, glutathione, and superoxide dismutase), total antioxidant capacity (TAC), and malondialdehyde (MDA) using ELISA. Also, DNA fragmentation was analyzed by the SDFA kit, and mitochondrial membrane potential (MMP) was assessed by rhodamine staining. Average sperm viability, motility, mitochondrial membrane potentiality, integrity of sperm membrane, and antioxidant enzyme levels are meaningfully reduced in the freezing group in contrast to the control group. The freezing group showed a meaningful rise in the mean MDA levels and DNA fragmentation compared to the control group. In the freezing group supplemented with carvacrol, a meaningful rise could be visible in mean percentages of viability, motility, and antioxidant enzyme levels, whereas mean levels of MDA and DNA fragmentation meaningfully declined in contrast to the freezing group. The results demonstrate that carvacrol, a potent antioxidant, offers significant protection against the loss generated by the freeze-thaw procedure, thereby improving sperm quality.

Evaluation of spermatic DNA fragmentation in smoking normospermic infertile individuals

Aim: In approximately 20% of infertile couples, the male factor is the only main cause. In recent years, it has been hypothesized that sperm DNA integrity may be a better indicator than routine semen analysis. Although the effects of smoking on male infertility have not yet been proven, smoking is considered a reasonable risk factor for infertility. In our study, we aimed to evaluate DNA damage in normospermic infertile men who smoke and do not smoke using the acridine orange method. Material and Methods: This study was conducted on semen samples from 50 male cases, 25 of whom were smokers and non-smokers, who met the infertility criteria and applied to the urology clinic of Dicle University Medical Faculty Hospital. Microscopic examinations and morphological evaluations were performed in accordance with the WHO 2010 criteria. The acridine orange method was applied to evaluate DNA fragmentation and DNA fragmentations were calculated. Statistical analysis of the obtained data was performed using the Mann-Whitney U Test. Results: In our study, in the smoking group, age was significantly associated with the duration of infertility, concentration with total motile sperm count, total sperm count with total motile sperm count, and amorphous head anomaly (p&lt;0.01). In the non-smoking group, age and infertility were significantly associated with the duration, volume and total count, concentration and total count, total motile sperm count, and DNA fragmentation (p&lt;0.01). However, there was no statistical difference between the smoking and non-smoking groups in terms of semen parameters and DNA fragmentation (p&gt;0.05). Conclusion: In order to obtain more reliable results, it is thought that large-scale studies are needed in the same groups and in the general population. Keywords: sperm, infertility, DNA fragmentation, smoking

The Motility Ratio method as a novel approach to qualify semen assessment.

Many scientific studies often assumed that the most reliable methods for assessing sperm motility are those that give the highest values, and this leads to misinterpretation of the results. This study aims to propose an objective method to validate sperm motility reliability. Bovine and porcine semen samples were split into two equal fractions. Fraction A was kept alive with a motile population considered at maximum proportion, while fraction B was killed with 0% motile population. A range of motile/non motile sperm was performed by mixing both fractions. The Motility Ratio method, comparing measured and theoretical motility, was validated using LEJA slide and IVOS II and applied to other slides. All slides showed strong Concordance Correlation Coefficient between measured and theoretical motility. However, with IVOS II, LEJA slide showed the lowest bias (< 1) while MAKLER or coverslip showed higher bias (> 2 and > 7 respectively) between measured and theoretical motility. This study shows that the best sperm motility is not always the true motility and highlights the importance of implementing a gold standard methodology for motility reliability such as The Motility Ratio method.

Microfluidic in compared with Zeta potential, MACS and swim up methods, resulted in improved chromatin integrity and high quality sperms.

Sperm parameters and DNA integrity are crucial factors in ART outcomes. This study compared four sperm preparation methods (microfluidics, MACS, zeta potential, and swim-Up) for sorting spermatozoa with normal parameters and chromatin integrity. This study evaluated semen samples from 25 couples with male factor infertility. The semen samples were divided into four portions: one prepared by MACS, one by zeta potential, the other by microfluidics, and the last by swim-up. After preparation, sperm viability, motility, and morphology were assessed based on the WHO guidelines. DNA intergrity was assessed by SDF assay, and the CMA3 staining test was used to evaluate sperm chromatin packaging. Compared to other preparation techniques, microfluidic preparation significantly improved sperm parameters, including motility, viability, morphology, and DNA integrity as well as chromatin packaging (p-value <0.05). The results also demonstrated that sperm motility, viability, and sperm DNA integrity as well as chromatin packaging, were not significantly different after preparation with MACS and Zeta potential methods. However, the MACS and Zeta methods produced improved sperm parameters and better DNA integrity than the swim-up method. Our results indicate that microfluidics can improve sperm quality compared to other methods of sperm preparation. When the microfluidic chip is not available, considering the similar results of sperm preparation by MACS and Zeta potential methods, it is preferred to use the Zeta method for the ART cycle due to its simplicity and cost-effectiveness.

Intracytoplasmic sperm injection versus conventional in vitro fertilization in infertile couples with normal total sperm count and motility: does sperm morphology matter?

Among couples with infertility and normal total sperm count and motility, can sperm morphology be used as a biomarker to identify couples who benefit more from ICSI over conventional IVF (c-IVF) on fertility outcomes? Based on this secondary analysis of a large randomized clinical trial (RCT), sperm morphology has limited value as a biomarker to identify couples who benefit more from ICSI over c-IVF on live birth, ongoing pregnancy, clinical pregnancy or total fertilization failure. Our recent RCT showed that ICSI did not result in higher live birth rates in couples with normal total sperm count and motility. It is unclear whether sperm morphology can be used as a biomarker to identify couples who benefit more from ICSI over c-IVF in this population. This was a secondary analysis of an open-label, multi-centre, RCT comparing ICSI versus c-IVF in 1064 couples with infertility and normal total sperm count and motility. In this secondary study, we evaluated the effectiveness of ICSI over c-IVF in relation to sperm morphology. Couples were eligible if they had ≤2 previous IVF/ICSI attempts, and the male partner had normal total sperm count and motility according to the fifth edition of the WHO laboratory manual for the examination and processing of human semen. Sperm morphology was measured from samples obtained during the first consultation and data for sperm morphology were available in partners of all participants in this trial. The outcomes of interest were live birth, ongoing pregnancy, clinical pregnancy, and total fertilization failure. We first conducted a logistic regression analysis with an interaction term (sperm morphology as a continuous variable by treatment (ICSI versus c-IVF)) on the four outcomes. We also used restricted cubic spline analysis to evaluate non-linear interaction and plotted the treatment effects of ICSI over c-IVF at different sperm morphology levels and the predicted probability of these outcomes in both ICSI and c-IVF groups. The median proportion of sperm with normal morphology in both groups was 3% (Interquartile range 1-6%). Live birth rates were (184/532) 34.6% for ICSI versus (166/532) 31.2% for c-IVF. No significant interaction was found between sperm morphology and treatment effect of ICSI versus c-IVF on the rates of live birth, ongoing pregnancy, clinical pregnancy, and total fertilization failure (P = 0.181, 0.153, 0.168, and 0.788 respectively). In the analyses using restricted cubic splines, no evidence of interaction between sperm morphology and the treatment effect was found. Interaction figures showed that the treatment effect of ICSI over c-IVF at different sperm morphology levels was fluctuating around no effect line, and the predicted outcomes for the two groups were mostly overlapping at different sperm morphology levels. This secondary analysis may be underpowered to detect a difference in treatment effects at different sperm morphology levels due to relatively small number of events at some sperm morphology levels. Moreover, sperm morphology assessment was performed during the first consultation, rather than on the day of randomization. In couples with infertility and normal total sperm count and motility, sperm morphology has a limited role as a biomarker to identify couples who benefit more from ICSI over c-IVF on fertility outcomes. This study was funded by My Duc Hospital, Ho Chi Minh City, Vietnam. RW was supported by an NHMRC EL Investigator Grant (GNT2009767). LNV has received speaker and conference fees from Merck, grant, speaker, conference fees from Merck Sharpe and Dohme, and speaker, conference, and scientific board fees from Ferring. TMH has received speaker fees from Merck, Merck Sharp Dohme, and Ferring. BWM reports consultancy, travel support and research funding from Merck and consultancy for Organon and Norgine. BWM holds stock from ObsEva. NCT03428919.

Alterations Expression of Key RNA Methylation (m6A) Enzymes in Testicular Tissue of Rats with Induced Varicocele.

Epigenetics impacts male fertility and reproductive disorders. RNA modifications, like m6A, influence RNA metabolism. Varicocele contributes to male infertility, and oxidative stress affects sperm function. This study investigates the expression of key RNA modification enzymes in a rat varicocele model, aiming to elucidate the relationship between varicocele, oxidative stress, and fertility. Fifteen male Wistar rats were divided into Control, Sham, and Varicocele induction groups. Varicocele was induced in the rats surgically. After 8 weeks, testicular tissues and sperm were collected for analysis, including histopathological assessment and evaluation of sperm parameters, functional tests, and gene expression of key RNA modification enzymes: METTL3 as a writer, ALKBH5 and FTO as erasers, and YTHDF2 as a reader involved in recognizing m6A-modified RNA using qRT-PCR. One-way ANOVAwithpost-hoc Tukey HSDwas used forcomparing tests within groups. Varicocele induction resulted in histological changes in testicular tissues, including irregularly variable-sized seminiferous tubules. Sperm parameters were significantly affected, with lower concentration, motility, and higher percentage of abnormal sperm in the varicocele group. Increased levels of oxidative stress markers (Sperm lipid peroxidation, and intracytoplasmic ROS) and sperm DNA damage were observed, indicating the presence of oxidative stress in varicocele. Moreover, the expression of key enzymes involved in RNA metabolism was downregulated in the varicocele group. These findings highlight the detrimental impact of varicocele on testicular health, sperm quality, and gene expression, providing insights into the underlying mechanisms of male infertility associated with varicocele.

Cordycepin improves hyperactivation and acrosome reaction through adenosine receptors during human sperm capacitation in vitro.

Sperm capacitation is a prerequisite for natural or in vitro fertilization. After capacitation, sperm become hyperactivated and undergo an acrosome reaction, which helps them penetrate the oocyte. Cordycepin, a bioactive compound first isolated from Cordyceps militaris, is an adenosine analog with numerous physiological activities. However, its effects on sperm capacitation remain unclear. This study aims to elucidate the effects and mechanisms of cordycepin on human sperm capacitation. During in vitro capacitation culture, healthy human sperm were treated with cordycepin (20, 100, 500 µM). Sperm motility and hyperactivation were detected using a computer-assisted sperm analyzer. Sperm acrosome reaction was measured using fluorescein isothiocyanate-conjugated Pisum sativum agglutinin. Sperm protein kinase A (PKA) activity was analyzed using an ELISA kit. The levels of sperm protein tyrosine phosphorylation were detected by western blotting. Sperm DNA damage was detected by a sperm chromatin dispersion assay. Reactive oxygen species (ROS) were measured using the fluorescence probe 2',7'-dichlorodihydrofluorescein diacetate. The expression and localization of adenosine receptors were analyzed by western blotting and immunofluorescence. The specific inhibitors of adenosine receptors were used to confirm their effects on cordycepin-induced sperm capacitation. Finally, molecular docking was performed to analyze the interaction between cordycepin and adenosine receptors. Cordycepin improved hyperactivated sperm motility, acrosome reaction, PKA activity, and protein tyrosine phosphorylation during capacitation while having no obvious effects on sperm ROS or DNA damage. Four adenosine receptor subtypes were expressed in human sperm, but their localizations differed. Inhibition of adenosine receptors significantly decreased cordycepin-induced sperm hyperactivation and the acrosome reaction. Molecular docking showed that cordycepin can bind to the four subtypes of adenosine receptors. Cordycepin may promote human sperm capacitation through adenosine receptor-mediated signaling pathways. These findings may be useful for assisted reproductive technology and animal breeding.

The Effect of Ketoconazole and Quinestrol Combination on Reproductive Physiology in Male Mice

This study investigates whether ketoconazole, a CYP3A4 inhibitor, can enhance the suppressive effects of quinestrol on reproductive capacity, potentially allowing for a reduced quinestrol dosage while maintaining its efficacy. A total of 104 healthy adult male mice were divided into two groups, assessed at 10 and 30 days. Within each group, six treatment categories were tested: the control (CK), quinestrol alone (Q1, Q5), and quinestrol combined with varying doses of ketoconazole (Q1 + K0.4, Q1 + K2, Q5 + K0.4). The key parameters measured included internal and reproductive organ weights, sperm density, sperm motility, sperm abnormalities, and CYP3A4 enzyme content in intestinal and liver tissues. After 10 days, the combination of a low dose of quinestrol with ketoconazole (Q1 + K0.4) showed the most significant pronounced effects in reducing reproductive potential, with notable reductions in epididymal weight, sperm density, sperm abnormality rate and vitality, serum hormone levels, and CYP3A4 content in the small intestine and liver. Although some reproductive parameters returned to near-baseline levels after 30 days, the Q1 + K0.4 regimen continued to exhibit reduced seminal vesicle weight and testosterone levels. Importantly, the combination did not significantly increase CYP3A4 enzyme content, indicating effective metabolic inhibition. The combination of quinestrol and ketoconazole, especially the Q1 + K0.4 regimen, demonstrated the most noticeable impact on reducing reproductive capacity. This regimen significantly reduced key reproductive parameters and showed strong metabolic inhibition, suggesting that ketoconazole substantially enhances the efficacy of quinestrol in fertility control.

Reorganization of the flagellum scaffolding induces a sperm standstill during fertilization.

Mammalian sperm delve into the female reproductive tract to fertilize the female gamete. The available information about how sperm regulate their motility during the final journey to the fertilization site is extremely limited. In this work, we investigated the structural and functional changes in the sperm flagellum after acrosomal exocytosis (AE) and during the interaction with the eggs. The evidence demonstrates that the double helix actin network surrounding the mitochondrial sheath of the midpiece undergoes structural changes prior to the motility cessation. This structural modification is accompanied by a decrease in diameter of the midpiece and is driven by intracellular calcium changes that occur concomitant with a reorganization of the actin helicoidal cortex. Midpiece contraction occurs in a subset of cells that undergo AE, and live-cell imaging during in vitro fertilization showed that the midpiece contraction is required for motility cessation after fusion is initiated. These findings provide the first evidence of the F-actin network's role in regulating sperm motility, adapting its function to meet specific cellular requirements during fertilization, and highlighting the broader significance of understanding sperm motility.

Reorganization of the flagellum scaffolding induces a sperm standstill during fertilization

Mammalian sperm delve into the female reproductive tract to fertilize the female gamete. The available information about how sperm regulate their motility during the final journey to the fertilization site is extremely limited. In this work, we investigated the structural and functional changes in the sperm flagellum after acrosomal exocytosis (AE) and during the interaction with the eggs. The evidence demonstrates that the double helix actin network surrounding the mitochondrial sheath of the midpiece undergoes structural changes prior to the motility cessation. This structural modification is accompanied by a decrease in diameter of the midpiece and is driven by intracellular calcium changes that occur concomitant with a reorganization of the actin helicoidal cortex. Midpiece contraction occurs in a subset of cells that undergo AE, and live-cell imaging during in vitro fertilization showed that the midpiece contraction is required for motility cessation after fusion is initiated. These findings provide the first evidence of the F-actin network’s role in regulating sperm motility, adapting its function to meet specific cellular requirements during fertilization, and highlighting the broader significance of understanding sperm motility.

Prediction model of male reproductive function damage caused by CHOP chemotherapy regimen for non-Hodgkin's lymphoma.

The CHOP combined chemotherapy regimen (cyclophosphamide, doxorubicin, vincristine, and prednisone) is commonly used to treat non-Hodgkin Lymphoma (NHL). While these drugs are effective for cancer treatment, they may have side effects on the reproductive system that are poorly studied. This study used a mouse model to investigate the mechanisms of reproductive function impairment induced by the CHOP regimen and developed a predictive model for assessing reproductive damage with a non-invasive procedure. From 2022 to 2023, we statistically analyzed the changes of reproductive function of NHL patients before and after receiving CHOP regimen in the First Affiliated Hospital of Xiamen University. The NHL mouse model was established and divided into CHOP treatment group and control group. The weight of testis and epididymis, sperm quality and motility were compared between the two groups. Histopathological examination of testicular tissue was performed to determine pathological changes. ELISA was used to measure the expression of cytokines and cytokine pathways in serum, protein expression was analyzed by immunohistochemistry, and protein and mRNA levels of cytokines and pathways were evaluated by Western blotting and qPCR. Using stepwise regression method to select important factors, a prediction model of reproductive system damage was constructed. Fifty-two NHL patients included in the questionnaire showed significant reproductive system damage after CHOP regimen treatment. The weight of testis and epididymis, as well as the number and vitality of sperm in the mouse model treatment group were significantly lower than those in the control group. Serum LH, FSH, estradiol and progesterone levels decreased significantly, while inhibin B levels increased significantly. There was no significant change in testosterone or prolactin levels. Inflammatory markers such as CSF-1, IL-1, IL-6, TGF-β1 and GDNF increased significantly, while the level of SOD1 decreased significantly. Immunohistochemical staining analysis showed that CAMP, Caspase3, CSF-1, GDNF, IL-1, IL-6, PRKACB, TGF-β1 and TXNDC5 were all expressed in spermatocytes, and the expression of therapeutic histones was significantly higher than that of the control group. Western blot analysis further detected the protein expression, and QPCR detected the mRNA content. The results showed that the expression of histone and mRNA in the treatment group was significantly higher than that in the control group. Stepwise regression method determined that estradiol (E2) was the most important variable in the prediction model, and the AUC for predicting reproductive damage was 1. The CHOP regimen induces male reproductive toxicity, potentially mediated through alterations in hormone levels and increased expression of inflammatory cytokines and oxidative stress. Using E2 as the sole predictor in the model accurately predicts the extent of reproductive damage, offering a non-invasive method for detecting reproductive system damage.

Investigation of the effect of serotonin-activated semen washing medium on sperm motility at the molecular level: a pilot study.

In Assisted Reproductive Technologies (ART), efficient sperm preparation is vital for successful fertilization, with washing media enhancing the process. This pilot study examines the molecular-level impact of a new serotonin-containing sperm-washing medium (Prototype) on sperm motility and ROS metabolism, comparing it with commercially available media (Origio and Irvine). Semen samples from thirty-one individuals underwent preparation using the swim-up method post-semen analysis. Each sample was separately washed with the Prototype, Origio and Irvine mediums. ROS formation was determined through flow cytometric, and AT2R and PRDX2 protein levels, associated with sperm motility, were assessed via Western blot. Statistical evaluation compared the findings among the three outlined media. Significant differences were found among three washing media in terms of total and progressive motility. The Prototype medium showed the highest increase in both total (66%) and progressive motility (59%), while the control group exhibited the lowest increases (41% and 27.7%, respectively). Regarding ROS levels, the prototype (11.5%) and Origio (10.7%) groups demonstrated a notable decrease, contrasting with Irvine (25.8%). Molecular assessment revealed a significant elevation in AT2R protein levels in the prototype medium (59%), compared to other media. Additionally, an increase in PRDX2 protein levels was observed in the prototype medium, although this didn't reach statistical significance. Serotonin-activated washing media for sperm preparation can be a suitable choice for selecting high-quality sperm in ART. A broader molecular analysis with a larger sample size is required to explore the mechanisms and effectiveness of using a serotonin-containing sperm-washing medium in routine ART.

A multivariate model for the prediction of pregnancy following laparoscopic artificial insemination of sheep.

The causes of variation in the success of laparoscopic artificial insemination (AI) in sheep are not well understood. As such, this study incorporated the contributions of multiple male and female factors relevant to the success of AI into a comprehensive prediction model for pregnancy success. Data from Merino ewes (N = 30 254) including age, uterine tone (1; pale/flaccid-5; turgid/pink), intra-abdominal fat (1; little to no fat present-5; high fat), time of insemination and sire used, were recorded during AI. A subset of semen per sire (N = 388) was thawed and assessed for volume, subjective motility, sperm concentration, and morphology. Sperm motility (CASA), viability and acrosome integrity (FITC-PNA/PI), membrane fluidity (M540/Yo-Pro), mitochondrial superoxide production (Mitosox Red/Sytox Green), lipid peroxidation (Bodipy C11), level of intracellular reactive oxygen species (H2DCFDA) and DNA fragmentation (Acridine Orange) were also assessed 0, 3 and 6h post-thaw. Logistic binomial regression revealed sperm concentration (P < 0.001), CASA parameters at 0h (PCA3; P = 0.03), viable acrosome intact sperm at 6h (P = 0.02), abnormal morphology (P < 0.001), uterine tone (P < 0.001) and intra-abdominal fat (P = 0.03) of ewes influenced likelihood of pregnancy. Results generated will help standardise the pre-screening and selection of semen and ewes prior to artificial breeding programs, reducing variation in the success of sheep AI.

Chemical castration in dogs using calcium chloride: effects on testicular hemodynamics and semen characteristic and serum levels of testosterone.

Dog overpopulation and stray dogs are global issues that are detrimental to public health and animal welfare. Thus, the goal of the current study was to provide alternatives for surgical castration. Therefore, calcium chloride was employed in this study, which might be an option for castration. Ten dogs were divided into two groups of five: a calcium chloride-treated group and a control group. The treated group received a single bilateral intratesticular injection of 1ml of sterile saline containing calcium chloride dihydrate (CaCl2•2 H2O) at a dose of 20mg/kg per testicle. While the control group was treated with 1ml of sterile saline solution, Semen and blood collection, as well as Doppler ultrasonography, were routinely carried out every week on days 0, 7, 14, 21, and 28 in order to evaluate the impact of the injection on semen parameters and testicular blood flow. The testicular volume and echogenicity in the CaCl2-treated group were significantly (P < 0.001) lower in weeks 2 through 4 than in the control group. Furthermore, in canine semen, CaCl2 dramatically decreased the amount, motility, and viability of sperm. When compared to vehicle-control animals, azoospermia was seen 2 weeks after the injection and persisted for the end of the study. The testes of all dogs were surgically removed at 30 days post-injection, and testes were put in 10% neutral buffered formalin for tissue processing. When compared to the control group, the average weight of testes in the chemical groups was dramatically reduced. Significant decreases in spermatogenic processes, necrosis, and degeneration of seminiferous tubules packed with necrotic debris, and fibrosed interstitial tissue, necrosed and calcified Sertoli, and Leydig cells were seen 30 days after CaCl2 injection. There was a significant decrease in testosterone levels compared to day 0 before CaCl2 injection and the control group. From weeks 1 through 4, there was a substantial decrease in both peak systolic velocity (PSV) and end-diastolic velocity (EDV) values (P < 0.001) following a single intratesticular injection of CaCl2. The resistance index (RI) and pulsatility index (PI) showed the opposite tendency. Based on the histopathological and semen evaluations in this investigation, the study concludes that a single intratesticular injection of CaCl2 appears to be a practical and generally applicable approach for chemical sterilization of dogs.

Cryopreservation of Noble Scallop Mimachlamys nobilis sperm: Optimization study of cooling rate and thawing temperature

In marine biology reproduction research, the cryopreservation of sperm is a crucial area, especially for economically valuable species. Effective freezing techniques help maintain genetic diversity and support sustainable development in aquaculture. This study examined the effects of freezing protocols and thawing methods on the cryopreservation of Mimachlamys nobilis sperm. Experimental results indicated that a cooling rate of 5 °C/min and an equilibration time of 5 minutes were the most suitable conditions for maintaining the structural and functional integrity of the sperm. Comparisons of different thawing temperatures showed that 38 °C provided the best results, minimizing ice recrystallization and cellular damage. Additionally, it was found that a 10 % concentration of DMSO effectively balanced protection and cytotoxicity, maintaining sperm viability and motility. Transmission electron microscopy further revealed the impact of freezing conditions on sperm, including damage to the plasma membrane, dissolution, blurring and swelling of the acrosome and mitochondria, and cristae fragmentation and loss. This study emphasizes the importance of optimizing freezing and thawing protocols and accurately controlling cryoprotectant concentration, providing key insights for the effective long-term preservation of M.nobilis sperm. This is significant for the conservation of marine organisms and aquaculture.