Oxidative stress and male infertility

Development of a thermotaxis and rheotaxis microfluidic device for motile spermatozoa sorting

Male infertility is a pervasive global reproductive challenge, primarily attributed to a decline in semen quality. Addressing this concern, there has been a growing focus on spermatozoa sorting in assisted reproductive technology. This study introduces a groundbreaking development in the form of a thermotaxis and rheotaxis microfluidic (TRMC) device designed for efficient motile spermatozoa sorting within a short 15-min timeframe. The TRMC device mimics the natural sperm sorting mechanism of the oviduct, selecting spermatozoa with superior motility and DNA integrity. The experimental outcomes demonstrate a remarkable enhancement in the percentage of progressive spermatozoa following sorting, soaring from 3.90% to an impressive 96.11% when subjected to a temperature decrease from 38 °C to 35 °C. Notably, sperm motility exhibited a substantial 69% improvement. The TRMC device exhibited a commendable recovery rate of 60.93%, surpassing current clinical requirements. Furthermore, the sorted spermatozoa displayed a notable reduction in the DNA fragmentation index to 6.94%, signifying a substantial 90% enhancement in DNA integrity. This remarkable advancement positions the TRMC device as highly suitable for applications in in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI), offering a promising solution to male infertility challenges.

Effect of dual tobacco smoking of hookah and cigarettes on semen parameters of infertile men

INTRODUCTION

The research regarding the effect of hookah smoking on health is still deficient, even though it has been proven to jeopardize human health by raising the hazard of different types of cancers, infections, and cardiovascular disease. We aimed to study the effect of dual tobacco smoking (hookah and cigarettes) on semen parameters of infertile men.

METHODS

In this cross-sectional study, we studied the effect of different types of smoking patterns on human semen parameters among men who visited IVF laboratories to do a seminal fluid analysis (SFA). A total number of 761 participants were included, divided into the following: 108 dual smokers, 219 hookah smokers, 222 cigarette smokers, and 212 non-smokers. To analyze the effect of dual smoking on normal morphology, an interaction term between the cigarette index and hookah index was used.

RESULTS

Multivariable regression analysis after adjustment for age, BMI, education level, children, chronic diseases, varicocele, testicular surgery history, infertility duration, and cause revealed no significant difference in the sperm concentration and the percentage of progressive motility between non-smokers, cigarette smokers, or hookah smokers. However, there was a significant difference in the log of normal morphology percentage between the three groups. Cigarette and hookah smoking were significantly associated with having lower percentages of normal morphology. There was a significant difference in the log-normal morphology %, where light and heavy dual smokers had the least exponential beta of log-normal morphology %, 0.43 (95% CI: 0.33-0.55) and 0.36 (95% CI: 0.24-0.53), respectively.

CONCLUSIONS

Dual tobacco smoking can adversely affect sperm morphology.

Recent Progress of Induced Spermatogenesis In Vitro

Sperm, a crucial gamete for reproduction in sexual reproduction, is generated through the proliferation, differentiation, and morphological transformations of spermatogonial stem cells within the specialized microenvironment of the testes. Replicating this environment artificially presents challenges. However, interdisciplinary advancements in physics, materials science, and cell engineering have facilitated the utilization of innovative materials, technologies, and structures for inducing in vitro sperm production. This article offers a comprehensive overview of research progress on inducing in vitro sperm production by categorizing techniques into two major systems based on matrix-based and non-matrix-based approaches, respectively. Detailed discussions are provided for both types of technology systems through comparisons of their similarities and differences, as well as research advancements. The aim is to provide researchers in this field with a comprehensive panoramic view while presenting our own perspectives and prospects.

Impact of chronic sleep deprivation on male reproductive health: Insights from testicular and epididymal responses in mice

BACKGROUND

Sleep deprivation (SD) can cause damage to the male reproductive system. However, the duration required for such damage and the specific sequence and severity of damage to the testis and epididymis remain unclear.

OBJECTIVE

To investigate the effects of different durations of SD on different parts of the testis and epididymis caput, corpus, and cauda.

METHODS

Adult ICR mice were randomly assigned to five groups: the SD group (SD for 18 h/day for 1, 2, 3, or 4 weeks), the SD + Vit E group (supplemented with Vit E 50 mg/kg/d during 4 weeks of SD, the SD+NS group (saline supplementation during 4 weeks of SD), the SD + RS group (5 weeks of recovery sleep after 4 weeks of SD), and a normal sleep control (Ctrl) group. Following the interventions, sperm parameters, testicular and epididymal histopathology, inflammatory response, and oxidative stress markers were compared between the groups.

RESULTS

Compared to the Ctrl group, the SD group showed a decrease in sperm motility and concentration from SD 2 W and SD 3 W, respectively. Decreases in sperm concentration and motility were more pronounced in the cauda compared to the caput and corpus. Pathological damage was less severe in the epididymis caput than in the corpus and cauda. After 4 weeks of SD, inflammation and oxidative stress increased in both testes and epididymis. Both sleep recovery and vitamin E supplementation showed significant improvements, though they did not fully reach the level of the Ctrl group.

CONCLUSION

Chronic SD for more than 2 weeks causes varying degrees of damage to the testis, epididymis caput, corpus, and cauda in male mice. This damage is not fully reversible after 5 weeks of sleep recovery and antioxidant stress treatment. These findings help us to identify and prevent SD damage to the male reproduction at an early stage.

A systematic review and meta-analysis of the placebo effect on both semen quality and male infertility

INTRODUCTION

Placebo influence on such objective indicators, as sperm quality and infertility, has not been studied previously, but some studies report that placebo may distort even objective outcomes. The aim of current study is to assess the placebo effect on fertility in patients suffering from sperm abnormalities and/or infertility.

EVIDENCE ACQUISITION

We conducted a search of two databases (Scopus and MEDLINE) and identified placebo-controlled clinical trials which focused on sperm abnormalities and/or male infertility treatment. Primary outcomes included changes in semen parameters (volume, total count, sperm concentration in semen, progressive motility, morphology (normal cells)). Secondary outcomes included DNA fragmentation and change in pregnancy rate.

EVIDENCE SYNTHESIS

Seventy-seven articles published from 1983 to 2022 were included. Statistically significant changes were observed for the following values: total sperm count, mean change 0.16 (95% CI 0.05, 0.26); P=0.004, I2=75.1%; and progressive motility, mean change 0.13 (95% CI 0.02, 0.24); P=0.026, I2=84.9%. In contrast, placebo did not affect sperm concentration, sperm volume, sperm morphology or DNA fragmentation index. The publication bias for all the values measured with Egger's test and funnel plots was low.

CONCLUSIONS

The current meta-analysis indicated a statistically significant increase of total sperm count and progressive motility in the placebo group. In contrast, placebo did not affect sperm concentration, sperm volume, sperm morphology and DNA fragmentation index. These findings should be considered while planning or analyzing placebo-controlled clinical trials.

Cyberpharmacology uncover the mechanism of the total Rhizoma Coptidis extracts ameliorate chronic atrophic gastritis

ETHNOPHARMACOLOGICAL RELEVANCE

Characterized by inflammation of the gastric mucosa, atrophy of gastric gland cells, and intestinal metaplasia, Chronic Atrophic Gastritis (CAG) is a precancerous lesion disease. In traditional Chinese medicine, Rhizoma Coptidis (RC) is extensively used for treating gastrointestinal disorders, mainly because RC alkaloids-based extracts are the main active pharmaceutical ingredients. Total Rhizoma Coptidis extracts (TRCE) is a mixture of Rhizoma Coptidis extracts from Rhizoma Coptidis with alkaloids as the main components. However, the efficacy and mechanism of TRCE on CAG need further study.

AIM OF THE STUDY

To explore the therapeutic effect and underlying mechanisms of action of TRCE on N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)-induced chronic atrophic gastritis (CAG) using network pharmacological analysis.

MATERIALS AND METHODS

The amelioration effect of TRCE on CAG was evaluated in MNNG-induced CAG mice. The pathological severity of the mice was evaluated through H&E staining. Detection of gastric mucosal parietal cell loss was conducted using immunofluorescence staining, and serum indices were measured using ELISA. Additionally, the active compounds and drug targets of Rhizoma Coptidis were curated from the STP, SEA, and TCMSP databases, alongside disease targets of CAG sourced from PharmGkb, OMIM, and GeneCards databases. By mapping drug targets to disease targets, overlapping targets were identified. A shared protein-protein interaction (PPI) and drug target network were constructed for the overlapping targets and analyzed for KEGG enrichment.

RESULTS

The results of animal experiments demonstrate that TRCE has the potential to improve the CAG process in mice. In conjunction with disease characteristics, cyberpharmacology analysis has identified nine core compounds, 151 targets, 10 core targets, and five significant inflammatory pathways within the compound-target-pathway network. Furthermore, there is a remarkable coincidence rate of 98% between the core compound targets of TRCE and the targets present in the CAG disease database. The accurate search and calculation of literature reports indicate that the coverage rate for 121 predicted core targets related to CAG reaches 81%. The primary characteristic of CAG lies in its inflammatory process. Both predicted and experimental findings confirm that TRCE can regulate ten key inflammation-associated targets (TP53, STAT3, AKT1, HSP90AA1, TNF, IL-6, MAPK3, SRC, JUN, and HSP90AA1) as well as inflammation-related pathways (MAPK, HIF-1, Toll-Like Receptor, IL-17, TNF, and other signaling pathways). These mechanisms mitigate inflammation and reduce gastric mucosal damage in CAG mice.

CONCLUSIONS

In conclusion, TRCE was shown to alleviate CAG by modulating TP53, STAT3, AKT1, HSP90AA1, TNF, IL-6, MAPK3, SRC, JUN, and EGFR, as demonstrated by combined network pharmacology and biological experiments. In conclusion, our study provides a robust foundation for future clinical trials evaluating the efficacy of RC in treating CAG.

Lipids, lipid-modified drug target genes, and the risk of male infertility: a Mendelian randomization study

Background

Previous observational studies have reported a possible association between circulating lipids and lipid-lowering drugs and male infertility (MIF), as well as the mediating role of circulating vitamin D. Then, due to issues such as bias, reverse causality, and residual confounding, inferring causal relationships from these studies may be challenging. Therefore, this study aims to explore the effects of circulating lipids and lipid-lowering drugs on MIF through Mendelian randomization (MR) analysis and evaluate the mediating role of vitamin D.

Method

Genetic variations related to lipid traits and the lipid-lowering effect of lipid modification targets are extracted from the Global Alliance for Lipid Genetics Genome-Wide Association Study. The summary statistics for MIF are from the FinnGen 9th edition. Using quantitative expression feature loci data from relevant organizations to obtain genetic variations related to gene expression level, further to explore the relationship between these target gene expression levels and MIF risk. Two-step MR analysis is used to explore the mediating role of vitamin D. Multiple sensitivity analysis methods (co-localization analysis, Egger intercept test, Cochrane's Q test, pleiotropy residuals and outliers (MR-PRESSO), and the leave-one-out method) are used to demonstrate the reliability of our results.

Result

In our study, we observed that lipid modification of four lipid-lowering drug targets was associated with MIF risk, the LDLR activator (equivalent to a 1-SD decrease in LDL-C) (OR=1.94, 95% CI 1.14-3.28, FDR=0.040), LPL activator (equivalent to a 1-SD decrease in TG) (OR=1.86, 95% CI 1.25-2.76, FDR=0.022), and CETP inhibitor (equivalent to a 1-SD increase in HDL-C) (OR=1.28, 95% CI 1.07-1.53, FDR=0.035) were associated with a higher risk of MIF. The HMGCR inhibitor (equivalent to a 1-SD decrease in LDL-C) was associated with a lower risk of MIF (OR=0.38, 95% CI 0.17-0.83, FDR=0.39). Lipid-modifying effects of three targets were partially mediated by serum vitamin D levels. Mediation was 0.035 (LDLR activator), 0.012 (LPL activator), and 0.030 (CETP inhibitor), with mediation ratios of 5.34% (LDLR activator), 1.94% (LPL activator), and 12.2% (CETP inhibitor), respectively. In addition, there was no evidence that lipid properties and lipid modification effects of six other lipid-lowering drug targets were associated with MIF risk. Multiple sensitivity analysis methods revealed insignificant evidence of bias arising from pleiotropy or genetic confounding.

Conclusion

This study did not support lipid traits (LDL-C, HDL-C, TG, Apo-A1, and Apo-B) as pathogenic risk factors for MIF. It emphasized that LPL, LDLR, CETP, and HMGCR were promising drug targets for improving male fertility.

Vigor King mitigates spermatogenic disorders caused by environmental estrogen zearalenone exposure

Zearalenone (ZEN) has been shown to cause reproductive damage by inducing oxidative stress. Astaxanthin and L-carnitine are widely used to alleviate oxidative stress and promote sperm maturation. However, it remains uncertain whether they are effective in mitigating spermatogenesis disorders induced by ZEN. This study aimed to investigate the therapeutic efficacy and potential mechanisms of Vigor King (Vig), a compound preparation primarily consisting of astaxanthin and L-carnitine, in alleviating ZEN-induced spermatogenesis disorders. In the experiment, mice received continuous oral gavage of ZEN (80 μg/kg) for 35 days, accompanied by a rescue strategy with Vig (200 mg/kg). The results showed that Vig effectively reduced the negative impact on semen quality and improved the structural and functional abnormalities of the seminiferous epithelium caused by ZEN. Additionally, the accumulation of reactive oxygen species (ROS), DNA double-strand breaks, apoptosis, and autophagy abnormalities were all significantly ameliorated. Intriguingly, the GSK3β-dependent BTRC-NRF2 signaling pathway was found to play an important role in this process. Furthermore, testing of offspring indicated that Vig could extend its protective effects to the next generation, effectively combating the transgenerational toxic effects of ZEN. In summary, our research suggests that Vig supplementation holds considerable promise in alleviating spermatogenesis disorders induced by zearalenone.

Diquat causes mouse testis injury through inducing heme oxygenase-1-mediated ferroptosis in spermatogonia

Diquat dibromide (DQ) is a globally used herbicide in agriculture, and its overuse poses an important public health issue, including male reproductive toxicity in mammals. However, the effects and molecular mechanisms of DQ on testes are limited. In vivo experiments, mice were intraperitoneally injected with 8 or 10 mg/kg/ day of DQ for 28 days. It has been found that heme oxygenase-1 (HO-1) mediates DQ-induced ferroptosis in mouse spermatogonia, thereby damaging testicular development and spermatogenesis. Histopathologically, we found that DQ exposure caused seminiferous tubule disorders, reduced germ cells, and increased sperm malformation, in mice. Reactive oxygen species (ROS) staining of frozen section and transmission electron microscopy (TEM) displayed DQ promoted ROS generation and mitochondrial morphology alterations in mouse testes, suggesting that DQ treatment induced testicular oxidative stress. Subsequent RNA-sequencing further showed that DQ treatment might trigger ferroptosis pathway, attributed to disturbed glutathione metabolism and iron homeostasis in spermatogonia cells in vitro. Consistently, results of western blotting, measurements of MDA and ferrous iron, and ROS staining confirmed that DQ increased oxidative stress and lipid peroxidation, and accelerated ferrous iron accumulation both in vitro and in vivo. Moreover, inhibition of ferroptosis by deferoxamine (DFO) markedly ameliorated DQ-induced cell death and dysfunction. By RNA-sequencing, we found that the expression of HO-1 was significantly upregulated in DQ-treated spermatogonia, while ZnPP (a specific inhibitor of HO-1) blocked spermatogonia ferroptosis by balancing intracellular iron homeostasis. In mice, administration of the ferroptosis inhibitor ferrostatin-1 effectively restored the increase of HO-1 levels in the spermatogonia, prevented spermatogonia death, and alleviated the spermatogenesis disorders induced by DQ. Overall, these findings suggest that HO-1 mediates DQ-induced spermatogonia ferroptosis in mouse testes, and targeting HO-1 may be an effective protective strategy against male reproductive disorders induced by pesticides in agriculture.

The Association Between the Levels of Oxidative Stress Indicators (MDA, SOD, and GSH) in Seminal Plasma and the Risk of Idiopathic Oligo-asthenotera-tozoospermia: Does Cu or Se Level Alter the Association?

Epidemiological studies on the associations between the levels of oxidative stress (OS) indicators (MDA, SOD, and GSH) in seminal plasma and the risk of idiopathic oligo-asthenotera-tozoospermia (OAT) are still inconsistent. Additionally, whether the associations can be altered by the status of essential trace elements is still unknown. To investigate the relationship between MDA, SOD, and GSH levels in seminal plasma and the risk of idiopathic OAT, and further to examine whether levels of iron (Fe), copper (Cu), and selenium (Se) in seminal plasma can alter the associations. A total of 148 subjects (75 idiopathic OAT cases and 73 controls) were included in this study. Seminal plasma samples from all the participants were measured for levels of MDA, SOD, GSH, Fe, Cu, and Se. Unconditional logistic regression models were used to examine the associations between three oxidative stress indicators and the risk of idiopathic OAT. Bayesian kernel machine regression was performed to determine the joint effects of levels of three OS indicators on the risk of idiopathic OAT. Subgroup analyses were performed to explore whether the above associations can be different when Fe, Cu, and Se were in different levels. The level of MDA in seminal plasma was positively associated with the risk of idiopathic OAT, with adjusted odds ratio (OR) and 95% confidence interval (CI) of 2.38 (1.17, 4.83), and SOD and GSH levels were not associated with the risk of idiopathic OAT. In BKMR analyses, we found a significant positive association between the mixture of MDA, SOD, and GSH levels and the risk of idiopathic OAT at concentrations below the 65th percentile, while a negative association at concentrations above it. In subgroup analysis, a positive association was observed between MDA levels in seminal plasma and the risk of idiopathic OAT in the high-Cu group (adjusted OR = 3.66, 95%CI = 1.16, 11.57), while no significant association was found in the low-Cu group (adjusted OR = 1.43, 95%CI = 0.44, 4.58). Additionally, a negative association was found between GSH levels in seminal plasma and the risk of idiopathic OAT in the high-Se group (adjusted OR = 0.34, 95%CI = 0.11, 0.99), while no significant association was observed in the low-Se group (adjusted OR = 1.96, 95%CI = 0.46, 8.27). The levels of MDA, SOD, and GSH in seminal plasma were associated with the risk of idiopathic OAT, and the levels of Cu and Se in seminal plasma may alter the associations.

Effect of Five Different Antioxidants on the Effectiveness of Goat Semen Cryopreservation

The effective combination of semen cryopreservation and artificial insemination has a positive effect on the conservation of germplasm resources, production and breeding, etc. However, during the process of semen cryopreservation, the sperm cells are very susceptible to different degrees of physical, chemical, and oxidative stress damage. Oxidative damage is the most important factor that reduces semen quality, which is affected by factors such as dilution equilibrium, change of osmotic pressure, cold shock, and enzyme action during the freezing-thawing process, which results in the aggregation of a large amount of reactive oxygen species (ROS) in sperm cells and affects the quality of semen after thawing. Therefore, the method of adding antioxidants to semen cryoprotective diluent is usually used to improve the effect of semen cryopreservation. The aim of this experiment was to investigate the effects of adding five antioxidants (GLP, Mito Q, NAC, SLS, and SDS) to semen cryoprotection diluent on the cryopreservation effect of semen from Saanen dairy goats. The optimal preservation concentrations were screened by detecting sperm viability, plasma membrane integrity, antioxidant capacity, and acrosomal enzyme activities after thawing, and the experimental results were as follows: the optimal concentrations of GLP, Mito Q, NAC, SLS, and SDS added to semen cryopreservation diluent at different concentrations were 0.8 mg/mL, 150 nmol/L, 0.6 mg/mL, 0.15 mg/ mL, 0.6 mg/mL, and 0.15 mg/mL. The optimal concentrations of the five antioxidants were added to the diluent and analyzed after 1 week of cryopreservation, and it was found that sperm viability, plasma membrane integrity, and mitochondrial activity were significantly enhanced after thawing compared with the control group (P < 0.05), and their antioxidant capacity was significantly enhanced (P < 0.05). Therefore, the addition of the above five antioxidants to goat sperm cryodilution solution had a better enhancement of sperm cryopreservation. This study provides a useful reference for exploring the improvement of goat semen cryoprotection effect.

The role of Cistanches Herba and its ingredients in improving reproductive outcomes: A comprehensive review

BACKGROUND

Infertility patients account for an astonishing proportion of individuals worldwide. Due to its complex etiology and challenging treatment, infertility has imposed significant psychological and economic burdens on many patients. C. Herba (Cistanche tubulosa (Schenk) Wight and Cistanche deserticola Ma), renowned as one of the most prominent Chinese herbal medicines (CHMs), is abundant in diverse bioactive compounds that exhibit therapeutic effects on many diseases related to oxidative stress (OS) and disorders of sex hormone levels.

OBJECTIVE

Due to the limited drugs currently used in clinical practice to improve reproductive outcomes and their inevitable side effects, developing safe and effective new medications for infertility is of significance. This article comprehensively reviewed the phytochemicals of C. Herba, focusing on their efficacy and mechanisms on infertility and their safety for the first time, aiming to offer valuable insights for the development and application of C. Herba, and for developing novel strategies for treating infertility.

METHODS

We used "Cistanche" and its known bioactive components in combination with "sperm", "testicles", "epididymis", "ovaries", "uterus", and "infertility" as keywords to search in PubMed, Web of Science, Scopus and CNKI up to November 2023. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guideline was followed.

RESULTS

The therapeutic effects of C. Herba on infertility are mainly attributed to echinacoside (ECH), verbascoside (VB), salidroside (SAL), polysaccharides, and betaine. They can effectively improve spermatogenic dysfunction, gonadal dysfunction and erectile dysfunction (ED) by exerting anti-oxidation, sex hormones regulation and anti-hypoxia. Moreover, they can also improve premature ovarian failure (POF), ovarian and uterine cancer, oocyte maturation by exerting anti-oxidation, anti-apoptosis, and anti-cancer. C. Herba and its active ingredients also exhibit pleasing safety.

CONCLUSION

C. Herba is a promising source of natural medicine for infertility. Additionally, compared to current therapeutic drugs, its favorable safety also supports its development as a nutritional supplement. However, high-quality clinical studies are required to validate its effectiveness for the development of novel therapeutic strategies.

The therapeutic effect and metabolic mechanism analysis of Guilingji on idiopathic oligo-asthenoteratozoospermia

Introduction

Guilingji, a famous traditional Chinese medicine (TCM) formula, has been used to combat aging and male sexual dysfunction in China for centuries. To date, there has been little evidence-based clinical research on the use of Guilingji to treat idiopathic oligo-asthenoteratozoospermia (OAT), and the therapeutic mechanism from a metabolic perspective needs to be investigated further.

Methods

This was a multicenter, double-blind, randomized controlled clinical study of 240 patients with idiopathic OAT recruited from four hospitals between January 2020 and January 2022. Patients were randomly assigned in a 1꞉1 ratio to receive oral Guilingji capsules or placebo for 12 weeks. The total progressive motile sperm count (TPMSC) was considered the primary outcome, and the other sperm parameters, seminal plasma parameters and serum hormones were considered the secondary outcome. A nontargeted metabolomics analysis of serum from OAT patients before and after Guilingji administration was performed by HPLC-MS to identify key metabolites. Furthermore, we used a rat model to show spermatogenesis phenotypes to validate the effect of the key metabolites screened from the patients.

Results

At weeks 4, 8 and 12, TPMSC and other sperm parameters were significantly improved in the Guilingji group compared with the placebo group (P < 0.05 for all comparisons). At week 4, superoxide dismutase (SOD) and acrosomal enzyme activity of seminal plasma were significantly elevated in the Guilingji group compared with the placebo group, while reactive oxygen species (ROS) levels were significantly reduced (P < 0.05). Lactate dehydrogenase-X (LDHX) levels appeared to be significantly increased after 12 weeks continuous medication compared with Placebo group (P = 0.032). The metabolomics analysis of serum from OAT patients before and after Guilingji administration showed that the glucose-6-phosphate (G6P) concentration in patients' serum was significantly elevated after Guilingji treatment. Compared to the control, when Kidney-Yang deficiency model rats were treated with Guilingji or its key intermediate metabolite G6P, their sperm concentration and spermatozoic activity were improved similarly, and their structural damage of rat's testicular and epididymal tissues were recovered.

Conclusion

This study provided valuable clinical evidence for the utility of Guilingji as a treatment for OAT. These findings thus demonstrate that G6P is involved in the therapeutic mechanism of Guilingji in OAT treatment based on clinical and rat intervention studies.

Follicular oocyte as a potential target for severe acute respiratory syndrome coronavirus 2 infection

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was reported in December 2019 and rapidly became a pandemic as coronavirus disease 2019 (COVID-19). Apart from other organs, presence of specific receptor angiotensin-converting enzyme (ACE2) and corresponding proteases such as transmembrane serine protease 2, basigin and cysteine protease cathepsin L make follicular somatic cells as well as oocyte as potential targets for SARS-CoV-2 infection. The SARS-CoV-2 causes inflammation and hypoxia that generate reactive oxygen species (ROS) in critically ill patients. In addition, a large number of casualties and insecurity of life due to repeated waves of SARS-CoV-2 infection generate psychological stress and cortisol resulting in the further generation of ROS. The excess levels of ROS under physiological range cause meiotic instability, while high levels result in oxidative stress that trigger various death pathways and affect number as well as quality of follicular oocytes. Although, emerging evidence suggests that the SARS-CoV-2 utilises cellular machinery of ovarian follicular cells, generates ROS and impairs quality of follicular oocytes, the underlying mechanism of viral entry into host cell and its negative impact on the follicular oocyte remains poorly understood. Therefore, this review summarises emerging evidence on the presence of cellular machinery for SARS-CoV-2 in ovarian follicles and the potential negative impact of viral infection on the follicular oocytes that affect ovarian functions in critically ill and stressed women.

Protective effect of Chlorella vulgaris on testicular damage, sperm parameters, androgen production, apoptosis and oxidative stress index in male rats following doxorubicin administration

Doxorubicin (DOX) is a chemotherapy agent associated with adverse effects on male reproductive health. Chlorella vulgaris (ChV) is a potent natural antioxidant with promising applications in maintaining health and preventing oxidative stress-related diseases. The present study aimed to investigate the protective effect of ChV on DOX-induced testicular toxicity. Twenty-five Wistar rats (230 ± 20 g) were randomly assigned to five groups (n = 5), including the control group, sham group (received normal saline by oral gavage daily and intraperitoneally (IP) once a week), DOX group (3 mg/kg; once a week; IP), ChV group (300 mg/kg/day; by oral gavage), and DOX (3 mg/kg; once a week; IP) + ChV (300 mg/kg/day; by oral gavage) group. After 8 weeks of treatment, the rats were euthanized and serum testosterone level, testes histomorphometry, gonadosomatic index (GSI), apoptotic gene expression, oxidative stress index, and sperm parameters were assessed. The results showed that DOX led to a significant decrease in histological indexes, testosterone level, GSI, sperm parameters, and Bcl-2 gene expression and increased expression of P-53 and Bax genes, and oxidative stress markers (P<0.05). The administration of ChV in the DOX+ChV group significantly improved testosterone levels, sperm parameters, testicular tissue apoptosis, antioxidant enzymes, and structural integrity of the testes (P<0.05). The findings suggest that the co-administration of ChV can be a promising therapeutic agent to reduce the adverse effects of DOX on male reproductive performance.

Oxidative Stress-Associated Male Infertility: Current Diagnostic and Therapeutic Approaches

Infertility is a prevalent global issue affecting approximately 17.5% of adults, with sole male factor contributing to 20-30% of cases. Oxidative stress (OS) is a critical factor in male infertility, disrupting the balance between reactive oxygen species (ROS) and antioxidants. This imbalance detrimentally affects sperm function and viability, ultimately impairing fertility. OS also triggers molecular changes in sperm, including DNA damage, lipid peroxidation, and alterations in protein expression, further compromising sperm functionality and potential fertilization. Diagnostic tools discussed in this review offer insights into OS markers, antioxidant levels, and intracellular ROS concentrations. By accurately assessing these parameters, clinicians can diagnose male infertility more effectively and thus tailor treatment plans to individual patients. Additionally, this review explores various treatment options for males with OS-associated infertility, such as empirical drugs, antioxidants, nanoantioxidants, and lifestyle modifications. By addressing the root causes of male infertility and implementing targeted interventions, clinicians can optimize treatment outcomes and enhance the chances of conception for couples struggling with infertility.

Contemporary Diagnostic Work-Up for Male Infertility: Emphasizing Comprehensive Baseline Assessment

Infertility is a prevalent issue affecting many couples during their reproductive years, with a significant number facing challenges in conceiving despite regular unprotected intercourse. Male factor infertility (MFI) contributes significantly to these cases, with a significant proportion of men lacking an identifiable etiology. As such, a thorough assessment of MFI has become increasingly vital for personalized management. This position paper from the Andrology team at IRCCS Ospedale San Raffaele emphasizes a comprehensive and individualized approach to MFI work-up, addressing the evolving challenges encountered in clinical practice. Our approach involves a thorough diagnostic work-up to identify the underlying causes of MFI, integrating insights from extensive literature review and our proprietary data. Our data demonstrates that an extensive diagnostic assessment allows us to identify at least one underlying cause of MFI in most infertile men. However, challenges persist in diagnosing less severe phenotypes with unclear etiology. We discuss the importance of individualized MFI work-up and its implications for developing rational therapeutic protocols. Lastly, this paper highlights the necessity for a personalized diagnostic assessment, addressing the daily clinical challenges and emphasizing tailored approaches to try to improve outcomes among couples seeking first medical help for infertility.

Octanoic acid mitigates busulfan-induced blood-testis barrier damage by alleviating oxidative stress and autophagy

BACKGROUND

The management of male infertility continues to encounter an array of challenges and constraints, necessitating an in-depth exploration of novel therapeutic targets to enhance its efficacy. As an eight-carbon medium-chain fatty acid, octanoic acid (OCA) shows promise for improving health, yet its impact on spermatogenesis remains inadequately researched.

METHODS

Mass spectrometry was performed to determine the fatty acid content and screen for a pivotal lipid component in the serum of patients with severe spermatogenesis disorders. The sperm quality was examined, and histopathological analysis and biotin tracer tests were performed to assess spermatogenesis function and the integrity of the blood-testis barrier (BTB) in vivo. Cell-based in vitro experiments were carried out to investigate the effects of OCA administration on Sertoli cell dysfunction. This research aimed to elucidate the mechanism by which OCA may influence the function of Sertoli cells.

RESULTS

A pronounced reduction in OCA content was observed in the serum of patients with severe spermatogenesis disorders, indicating that OCA deficiency is related to spermatogenic disorders. The protective effect of OCA on reproduction was tested in a mouse model of spermatogenic disorder induced by busulfan at a dose 30 mg/kg body weight (BW). The mice in the study were separated into distinct groups and administered varying amounts of OCA, specifically at doses of 32, 64, 128, and 256 mg/kg BW. After evaluating sperm parameters, the most effective dose was determined to be 32 mg/kg BW. In vivo experiments showed that treatment with OCA significantly improved sperm quality, testicular histopathology and BTB integrity, which were damaged by busulfan. Moreover, OCA intervention reduced busulfan-induced oxidative stress and autophagy in mouse testes. In vitro, OCA pretreatment (100 µM) significantly ameliorated Sertoli cell dysfunction by alleviating busulfan (800 µM)-induced oxidative stress and autophagy. Moreover, rapamycin (5 µM)-induced autophagy led to Sertoli cell barrier dysfunction, while OCA administration exerted a protective effect by alleviating autophagy.

CONCLUSIONS

This study demonstrated that OCA administration suppressed oxidative stress and autophagy to alleviate busulfan-induced BTB damage. These findings provide a deeper understanding of the toxicology of busulfan and a promising avenue for the development of novel OCA-based therapies for male infertility.

Bioanalysis of Stress Biomarkers through Sensitive HILIC-MS/MS Method: A Stride toward Accurate Quantification of MDA, ACR, and CTA

Quantifying reactive aldehyde biomarkers, such as malondialdehyde, acrolein, and crotonaldehyde, is the most preferred approach to determine oxidative stress. However, reported analytical methods lack specificity for accurately quantifying these aldehydes as certain methodologies may produce false positive results due to harsh experimental conditions. Thus, in this research work, a novel HILIC-MS/MS method with endogenous histidine derivatization is developed, which proves to have higher specificity and reproducibility in quantifying these aldehydes from the biological matrix. To overcome the reactivity of aldehyde, endogenous histidine is used for its derivatization. The generated adduct is orthogonally characterized by NMR and LC-HRMS. The method employed a hydrophilic HILIC column and multiple reaction monitoring (MRM) to accurately quantify these reactive aldehydes. The developed method is an unequivocal solution for quantifying stress in in vivo and in vitro studies.

Inflammatory macrophage reprogramming strategy of fucoidan microneedles-mediated ROS-responsive polymers for rheumatoid arthritis

During the pathogenesis of rheumatoid arthritis, inflammatory cells usually infiltrate synovial tissues, notably, M1-type macrophages, whose redox imbalance leads to the degradation of joint structures and deterioration of function. Natural active products play a vital role in immune modulation and antioxidants. In this study, we constructed a ROS-responsive nanoparticle called FTL@SIN, which consists of fucoidan (Fuc) and luteolin (Lut) connected by a ROS-responsive bond, Thioketal (TK), and encapsulated with an anti-rheumatic drug, Sinomenine (SIN), for synergistic anti-inflammatory effects. The FTL@SIN is then dispersed in high molecular weight Fuc-fabricated dissolvable microneedles (FTL@SIN MNs) for local administration. Therapy of FTL@SIN MNs afforded a significant decrease in macrophage inflammation while decreasing key pro-inflammatory cytokines and repolarizing M1 type to M2 type, thereby ameliorating synovial inflammation, and promoting cartilage repair. Additionally, our investigations have revealed that Fucoidan (Fuc) demonstrates synergistic effects, exhibiting superior mechanical strength and enhanced physical stability when compared to microneedles formulated solely with hyaluronic acid. This study combines nanomedicine with traditional Chinese medicine, a novel drug delivery strategy that presents a promising avenue for therapeutic intervention in rheumatoid arthritis.

Bibliometrics and visualization analysis of literature on male hypogonadism from 2000 to 2023: research focus and frontiers

Male hypogonadism can seriously affect male health and fertility, yet comprehensive bibliometric and visualization analyses of research in this area have been lacking. This study aimed to examine the distribution of literature, identify research hotspots, and discern development trends in male hypogonadism by analyzing 4026 English documents published between 2000 and 2023 using bibliometric and visual analyses. The results indicated a significant increase in publications and citations related to male hypogonadism over the past two decades, with the United States, the University of Florence, Maggi M, and the Journal of Clinical Endocrinology & Metabolism recognized as the most productive and highly cited country, institution, author, and journal, respectively. The article titled "The GPR54 gene as a regulator of puberty" received the highest number of citations. The keywords were categorized into four distinct clusters, including the etiology and pathogenesis of male hypogonadism, symptoms of late-onset hypogonadism, testosterone replacement therapy and its contraindications, the correlation between male hypogonadism and metabolic syndrome (MetS), obesity, and the epidemiology of male hypogonadism. The most frequently co-occurring keywords were "hypogonadism", "testosterone", and "men", while "oxidative stress" was the most prominent burst keyword. The analysis also identified "male infertility" and "oxidative stress" as the primary burst keywords in the last five years, indicating their emerging high-interest topics. Overall, this study provides a comprehensive overview of male hypogonadism research, offering valuable insights for researchers interested in this area, including potential collaborators, current research hotspots, and future research directions.

Protective effect of curcumin on testicular damage caused by carbon tetrachloride exposure in rats

Context Carbon tetrachloride (CCl4 ) is a chemical that is still widely used in industry and has been shown to cause structural defects in rat testicles through oxidative stress. Aims In our study, the effect of curcumin on CCl4 -mediated testicular damage was investigated. Methods Twenty-four adult Wistar albino male rats weighing 300-350g were divided into four groups: control group (olive oil was applied by gavage every consecutive day for 3weeks); curcumin and CCl4 +curcumin groups (200mg/kg curcumin dissolved in olive oil was given by gavage once a day, every consecutive day for 3weeks); and CCl4 and CCl4 +curcumin groups (0.5mL/kg CCl4 was dissolved in olive oil at a ratio of 1/1 and given by i.p. injection every other day for 3weeks). Tissue samples were examined histopathologically, histomorphometrically, immunohistochemically and biochemically. Key results CCl4 disrupted both testicular morphology and testosterone synthesis, whereas curcumin treatment resulted in an improvement in testicular morphology and biochemical parameters, as well as a decrease in caspase-3 and tumour necrosis factor-α expression. Conclusions Curcumin has a protective effect on testicular tissue damage caused by CCl4 with its anti-inflammatory, antiapoptotic and antioxantioxidant properties. Implications Curcumin can prevent testicular damage due to CCl4 , an environmental pollutant.

Microplastics from face mask impairs sperm motility

The COVID-19 pandemic has resulted in unprecedented plastic pollution from single-used personal protective equipment (PPE), especially face masks, in coastal and marine environments. The secondary pollutants, microplastics from face masks (mask MP), rise concern about their detrimental effects on marine organisms, terrestrial organisms and even human. Using a mouse model, oral exposure to mask MP at two doses, 0.1 and 1 mg MP/day for 21 days, caused no change in animal locomotion, total weight, or sperm counts, but caused damage to sperm motility with increased curvilinear velocity (VCL). The high-dose mask MP exposure caused a significant decrease in linearity (LIN) of sperm motility. Further testicular transcriptomic analysis revealed perturbed pathways related to spermatogenesis, oxidative stress, inflammation, metabolism and energy production. Collectively, our findings substantiate that microplastics from face masks yield adverse effects on mammalian reproductive capacity, highlighting the need for improved plastic waste management and development of environmentally friendly materials.

D-Limonene Alleviates Oxidative Stress Injury of the Testis Induced by Arsenic in Rat

Long-term exposure to arsenic can lead to testicular damage and lower sperm quality in males, which is mediated by increased arsenic-induced oxidative stress and other damage mechanisms. D-Limonene, which is rich in oranges, lemons, oranges, grapes and other natural fruits, can relieve doxorubicin (DOX)-induced kidney injury and CCL4-induced cardiac toxicity by inhibiting oxidative stress and inflammatory response. The antioxidant and anti-inflammatory properties of D-limonene motivate us to further explore whether it can reduce arsenic-induced testicular injury. To verify this scientific hypothesis, testicular pathology, testicular oxidative stress levels and sperm motility were determined after intervention with D-limonene in rats chronically exposed to arsenic. As expected, long-term arsenic exposure caused testicular tissue structure disturbances, increased levels of oxidative stress, and decreased sperm activation, all of which were significantly inhibited due to treatment with D-limonene. In conclusion, our data reveal a previously unproven beneficial effect of D-limonene, namely that D-limonene can inhibit arsenic-induced testicular injury, and also provide theoretical and experimental basis for the application of D-limonene in the treatment of arsenic-induced testicular injury.

Role of hydrogen sulfide in the male reproductive system

As an important gas signaling molecule, hydrogen sulfide (H2S) affects multiple organ systems, including the nervous, cardiovascular, digestive, and genitourinary, reproductive systems. In particular, H2S not only regulates female reproductive function but also holds great promise in the treatment of male reproductive diseases and disorders, such as erectile dysfunction, prostate cancer, varicocele, and infertility. In this review, we summarize the relationship between H2S and male reproductive organs, including the penis, testis, prostate, vas deferens, and epididymis. As lower urinary tract symptoms have a significant impact on penile erection disorders, we also address the potential ameliorative effects of H2S in erectile dysfunction resulting from bladder disease. Additionally, we discuss the regulatory role of H2S in cavernous smooth muscle relaxation, which involves the NO/cGMP pathway, the RhoA/Rho-kinase pathway, and K+ channel activation. Recently, various compounds that can alleviate erectile dysfunction have been reported to be at least partly dependent on H2S. Therefore, understanding the role of H2S in the male reproductive system may help develop novel strategies for the clinical treatment of male reproductive system diseases.

Sperm freezing damage: the role of regulated cell death

Substantial progress in research on sperm cryopreservation has occurred since the twentieth century, especially focusing on improving sperm freezing procedures and optimizing semen extenders. However, the cellular biological mechanisms of sperm freezing damage are still unclear, which greatly restricts the promotion and development of sperm cryopreservation. An essential component of sperm freezing damage is the occurrence of cell death. Considering the existence of multiple types of cell death pathways, this review discusses connections between characteristics of regulated cell death (e.g., apoptosis and ferroptosis), and accidental cell death (e.g., intracellular ice crystals) with sperm freezing damage and explores possible future research directions in this field.

Tert-Butylhydroquinone Mitigates T-2-Toxin-Induced Testicular Dysfunction by Targeting Oxidative Stress, Inflammation, and Apoptosis in Rats

Tert-butylhydroquinone (tBHQ) has emerged as a promising candidate for mitigating the adverse effects of T-2-induced reproductive toxicity. The protective effects of tBHQ on rat sperm quality, testicular injury, apoptosis, and inflammation induced by T-2 toxin exposure were investigated. Histopathological examination of testicular tissues revealed severe damage in the T-2-treated group, characterized by disorganized germ cell arrangement, thinning of the convoluted seminiferous tubule walls, and significant cellular necrosis. However, tBHQ administration, either as a preventive or therapeutic measure, mitigated this structural damage. Image analysis confirmed an increase in the cross-sectional area and height of the convoluted seminiferous tubules in the tBHQ-treated groups compared to the T-2-treated group (p < 0.05), indicating tBHQ's efficacy in alleviating testicular damage. Additionally, tBHQ treatment significantly inhibited T-2-induced apoptosis of testicular tissue cells, as evidenced by the results showing reduced apoptotic cell counts and downregulation of the BAX/BCL2 ratio and caspase-3 expression (p < 0.05). tBHQ significantly increased the concentrations of the antioxidant factors SOD, CAT, TAC, and GSH-PX. Furthermore, tBHQ attenuated the inflammatory response induced by T-2 exposure, as indicated by the decreased mRNA expression of the proinflammatory cytokines Tnf, Il1, and Il10 in testicular tissue (p < 0.05). Additionally, tBHQ treatment alleviated the decline in serum testosterone induced by the T-2 and promoted testosterone synthesis gene expression, including for the genes 17β-HSD and Cyp11a1, in rat testes (p < 0.05). These findings underscore tBHQ's role as a therapeutic agent combatting T-2-induced reproductive toxicity, highlighting its antioxidative, anti-apoptotic, and anti-inflammatory properties. Further elucidation of tBHQ's mechanisms of action may offer novel strategies for preventing and treating reproductive disorders induced by environmental toxins.

Antioxidant treatment for oligoasthenoteratozoospermia and varicocele: a DBPC trial to evaluate the impact of age and body mass index

Oxidative stress is one of the main mechanisms responsible for male infertility. Various conditions such as varicocele, obesity, advanced age, and lifestyle can lead to an increase in reactive oxygen species, causing an oxidative imbalance in the reproductive environment. Spermatozoa are sensitive to reactive oxygen species and require energy to carry out their main function of fertilizing the egg. Excessive reactive oxygen species can affect sperm metabolism, leading to immobility, impaired acrosome reaction, and cell death, thereby impairing reproductive success. This double-blind randomized study evaluated the effect of supplementation with L-carnitine, acetyl-L-carnitine, vitamins, and other nutrients on semen quality in 104 infertile patients with or without varicocele, while also investigating the impact of factors such as obesity and advanced age on treatment. Sperm concentration significantly increased in the supplemented group compared to the placebo group ( P = 0.0186). Total sperm count also significantly increased in the supplemented group ( P = 0.0117), as did sperm motility ( P = 0.0120). The treatment had a positive effect on patients up to 35 years of age in terms of sperm concentration ( P = 0.0352), while a body mass index (BMI) above 25 kg m -2 had a negative effect on sperm concentration ( P = 0.0110). Results were not showing a net benefit in stratifying patients in accordance with their BMI since sperm quality increase was not affected by this parameter. In conclusion, antioxidant supplementation may be beneficial for infertile patients and has a more positive effect on younger patients with a normal weight.

Exploring the impact of pericentric inversion of chromosome 9 on fertility in sperm donors

Pericentric inversion of chromosome 9 (inv[9]) is a common chromosomal structural variant, but its impact on clinical outcomes remains debated. The screening criteria of sperm banks are rarely mentioned to individuals with inv(9). In this study, we evaluated the fertility of sperm donors with inv(9) who met eligibility criteria for sperm banks (inv[9]-eligible donors). From March 2004 to May 2022, chromosomal analysis of 16 124 sperm donors at CITIC-Xiangya Human Sperm Bank in Hunan Province (Changsha, China) found that 251 (1.6%) had chromosome variations, with inv(9) being the most prevalent at 1.1%. All 169 inv(9)-eligible donors were contacted to collect fertility outcome data, along with 206 eligible donors without inv(9) as controls. In addition, semen samples from inv(9)-eligible donors and eligible donors underwent assessments of sperm fluorescence in situ hybridization (FISH), mitochondrial membrane potential, DNA fragmentation index, acrosome integrity, reactive oxygen species (ROS), and sperm morphology. Results showed that inv(9) did not significantly increase reproductive risks overall. Despite detecting ROS level differences, the clinical impact may be insignificant. This study provides new data on the inv(9) population that can serve as a valuable reference for decision-making by sperm banks as well as for genetic counseling and clinical guidance for individuals carrying inv(9) variant.

A metabolomic perspective on the mechanisms by which environmental pollutants and lifestyle lead to male infertility

The incidence of male infertility (MI) is rising annually. According to epidemiological studies, environmental pollution (e.g., organic, inorganic, and air pollutants), occupational exposure (e.g., high temperature, organic solvents, and pesticides), and poor lifestyle (e.g., diet, sleep, smoking, alcohol consumption, and exercise) are important non-genetic causative factors of MI. Due to multiple and complex causative factors, the dose-effect relationship, and the uncertainty of pathogenicity, the pathogenesis of MI is far from fully clarified. Recent data show that the pathogenesis of MI can be monitored by the metabolites in serum, seminal plasma, urine, testicular tissue, sperm, and other biological samples. It is considered that these metabolites are closely related to MI phenotypes and can directly reflect the individual pathological and physiological conditions. Therefore, qualitative and quantitative analysis of the metabolome, the related metabolic pathways, and the identification of biomarkers will help to explore the MI-related metabolic problems and provide valuable insights into its pathogenic mechanisms. Here, we summarized new findings in MI metabolomics biomarkers research and their abnormal metabolic pathways triggered by the presented non-genetic risk factors, providing a metabolic landscape of semen and seminal plasma in general MI patients. Then, we compared the similarities and differences in semen and seminal plasma biomarkers between MI patients exposed to environmental and poor lifestyle factors and MI patients in general, and summarized some common biomarkers. We provide a better understanding of the biological underpinnings of MI pathogenesis, which might offer novel diagnostic, prognostic, and precise treatment approaches to MI.

Role of Lipoic Acid in Testosterone Production in Males

Testosterone extends its impact beyond sexual function, playing a crucial role in shaping overall male health, including aspects such as muscle mass, bone density, mood regulation, and energy levels. Lipoic acid, a cofactor for specific enzymes, particularly dehydrogenases involved in cellular energy production, has been studied for its impact on testosterone. This comprehensive review systematically scoured PubMed and Scopus databases using the keywords "lipoic acid" and "testosterone." It encompassed all relevant English papers published from November 1971 to the present, including full texts and abstracts, along with research elucidating the biochemical mechanisms linking lipoic acid to testosterone. In summary, lipoic acid consistently restores testosterone levels, offering promise as an intervention in testicular health, especially in cases of testicular toxicity caused by various harmful agents. Its mechanisms encompass nitric oxide enhancement, fortification of testicular antioxidants, elevation of luteinizing hormone, enhancement of steroidogenesis, and the maintenance of energy production. These mechanisms underscore the therapeutic potential of lipoic acid for testicular health.

LanCL2 Implicates in Testicular Redox Homeostasis and Acrosomal Maturation

Redox balance plays an important role in testicular homeostasis. While lots of antioxidant molecules have been identified as widely expressed, the understanding of the critical mechanisms for redox management in male germ cells is inadequate. This study identified LanCL2 as a major male germ cell-specific antioxidant gene that is important for testicular homeostasis. Highly expressed in the brain and testis, LanCL2 expression correlates with testicular maturation and brain development. LanCL2 is enriched in spermatocytes and round spermatids of the testis. By examining LanCL2 knockout mice, we found that LanCL2 deletion did not affect postnatal brain development but injured the sperm parameters of adult mice. With histopathological analysis, we noticed that LanCL2 KO caused a pre-maturation and accelerated the self-renewal of spermatogonial stem cells in the early stage of spermatogenesis. In contrast, at the adult stage, LanCL2 KO damaged the acrosomal maturation in spermiogenesis, resulting in spermatogenic defects with a reduced number and motility of spermatozoa. Furthermore, we show that this disruption of testicular homeostasis in the LanCL2 KO testis was due to dysbalanced testicular redox homeostasis. This study demonstrates the critical role of LanCL2 in testicular homeostasis and redox balance.

Multiple transcriptome analyses reveal mouse testis developmental dynamics

The testes are the organs of gamete production and testosterone synthesis. Up to date, no model system is available for mammalian testicular development, and only few studies have characterized the mouse testis transcriptome from no more than three postnatal ages. To describe the transcriptome landscape of the developing mouse testis and identify the potential molecular mechanisms underlying testis maturation, we examined multiple RNA-seq data of mouse testes from 3-week-old (puberty) to 11-week-old (adult). Sperm cells appeared as expected in 5-week-old mouse testis, suggesting the proper sample collection. The principal components analysis revealed the genes from 3w to 4w clustered away from other timepoints, indicating they may be the important nodes for testicular development. The pairwise comparisons at two adjacent timepoints identified 7,612 differentially expressed genes (DEGs), resulting in 58 unique mRNA expression patterns. Enrichment analysis identified functions in tissue morphogenesis (3-4w), regulation of peptidase activity (4-5w), spermatogenesis (7-8w), and antigen processing (10-11w), suggesting distinct functions in different developmental periods. 50 hub genes and 10 gene cluster modules were identified in the testis maturation process by protein-protein interaction (PPI) network analysis, and the miRNA-lncRNA-mRNA, miRNA-circRNA-mRNA and miRNA-circRNA-lncRNA-mRNA competing endogenous RNA (ceRNA) networks were constructed. The results suggest that testis maturation is a complex developmental process modulated by various molecules, and that some potential RNA-RNA interactions may be involved in specific developmental stages. In summary, this study provides an update on the molecular basis of testis development, which may help to understand the molecular mechanisms of mouse testis development and provide guidance for mouse reproduction.

Kaempferol alleviates bisphenol A reproductive toxicity in rats in a dose-dependent manner

BACKGROUND

Endocrine-disrupting chemicals (EDCs), including bisphenol A (BPA), are a major cause of male infertility by disrupting spermatogenesis.

OBJECTIVE

Here, we examined the potential protective benefits of kaempferol (KMF), a flavonol known for its antioxidant properties, on BPA-induced reproductive toxicity in adult male rats.

METHODS

Human skin fibroblast cells (HNFF-P18) underwent cell viability assays. Thirty-five male Wistar rats were assigned to four groups: 1) control, 2) BPA (10 mg/kg), 3,4) BPA, and different dosages of KMF (1 and 10 mg/kg). The study examined the rats' testosterone serum level, antioxidant enzymes catalase (CAT) and superoxide dismutase (SOD), oxidative markers malondialdehyde (MDA) and total antioxidant capacity (TAC), body weight, weight ratios of testis and prostate, and histopathological examinations.

RESULTS

The study revealed that using KMF to treat rats exposed to BPA increased cell viability. Moreover, the rats' testosterone levels, which BPA reduced, showed a significant increase after KMF was included in the treatment regimen. Treatment with BPA led to oxidative stress and tissue damage, but simultaneous treatment with KMF restored the damaged tissue to its normal state. Histopathology studies on testis and prostate tissues showed that KMF had an ameliorative impact on BPA-induced tissue damage.

CONCLUSIONS

The research suggests that KMF, a flavonol, could protect male rats from the harmful effects of BPA on reproductive health, highlighting its potential healing properties.

Nrf2-mediated ferroptosis of spermatogenic cells involved in male reproductive toxicity induced by polystyrene nanoplastics in mice

Microplastics (MPs) and nanoplastics (NPs) have become hazardous materials due to the massive amount of plastic waste and disposable masks, but their specific health effects remain uncertain. In this study, fluorescence-labeled polystyrene NPs (PS-NPs) were injected into the circulatory systems of mice to determine the distribution and potential toxic effects of NPs in vivo. Interestingly, whole-body imaging found that PS-NPs accumulated in the testes of mice. Therefore, the toxic effects of PS-NPs on the reproduction systems and the spermatocytes cell line of male mice, and their mechanisms, were investigated. After oral exposure to PS-NPs, their spermatogenesis was affected and the spermatogenic cells were damaged. The spermatocyte cell line GC-2 was exposed to PS-NPs and analyzed using RNA sequencing (RNA-seq) to determine the toxic mechanisms; a ferroptosis pathway was found after PS-NP exposure. The phenomena and indicators of ferroptosis were then determined and verified by ferroptosis inhibitor ferrostatin-1 (Fer-1), and it was also found that nuclear factor erythroid 2-related factor 2 (Nrf2) played an important role in spermatogenic cell ferroptosis induced by PS-NPs. Finally, it was confirmed in vivo that this mechanism of Nrf2 played a protective role in PS-NPs-induced male reproductive toxicity. This study demonstrated that PS-NPs induce male reproductive dysfunction in mice by causing spermatogenic cell ferroptosis dependent on Nrf2.

Melatonin alleviates di-butyl phthalate (DBP)-induced ferroptosis of mouse leydig cells via inhibiting Sp2/VDAC2 signals

As one of the endocrine-disrupting chemicals (EDCs), dibutyl phthalate (DBP) has been extensively used in industry. DBP has been shown to cause damage to Leydig cells, yet its underlying mechanism remains elusive. In this study, we show that DBP induces ferroptosis of mouse Leydig cells via upregulating the expression of Sp2, a transcription factor. Also, Sp2 is identified to promote the transcription of Vdac2 gene by binding to its promoter and subsequently involved in DBP-induced ferroptosis of Leydig cells. In addition, DBP is proved to induce ferroptosis via inducing oxidative stress, while inhibition of oxidative stress by melatonin alleviates DBP-induced ferroptosis and upregulation of Sp2 and VDAC2. Taken together, our findings demonstrate that melatonin can alleviate DBP-induced ferroptosis of mouse Leydig cells via inhibiting oxidative stress-triggered Sp2/VDAC2 signals.

Bibliometric and visual analysis on oxidative stress in gynecological and reproductive diseases: A systematic review

BACKGROUND

The imbalance between the generation and elimination of reactive oxygen species (ROS) is defined as oxidative stress (OS). Elevated levels of OS are implicated in various diseases, especially in gynecological and reproductive disorders. The abundance of recent literature makes it challenging to assimilate all available information. This bibliometric analysis seeks to depict the research landscape of OS in gynecological and reproductive diseases and to identify future hotspots and trends.

METHODS

The Web of Science Core Collection served as the source for articles related to OS in gynecological and reproductive diseases. CtieSpace and VOSviewer software were utilized to analyzed countries/regions, institutions, journals, authors, and keywords of all eligible articles.

RESULTS

A total of 1423 articles were included. There was a gradual increase in the number of publications in this field. The USA maintained the highest number of publications, with 372 articles. Cleveland Clinic was the leading institution in terms of publication volume, contributing 67 articles. In total, 6925 authors were identified. Agarwal A as the most frequently co-cited author, received 812 citations across 43 publications. The predominant clusters included "placenta," "polycystic ovary syndrome," "male infertility," and "oocyte quality." Notably, "oocyte quality'" was identified as a current key research topic.

CONCLUSION

There was an uptrend in the number of articles addressing OS in gynecological and reproductive diseases. However, international collaboration and exchange were limited. The topic of male infertility had remained a consistent area of interest, and research on oocyte quality is poised to become a potential focal point in the future.

Protective effect of didymin against 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin-induced reproductive toxicity in male rats

PURPOSE

2, 3, 7, 8-Tetrachlorodibenzo-p-dioxin (TCDD) is one of the most potent environmental toxicants, which causes oxidative stress and adversely affects the male reproductive system. The current study aimed to evaluate the ameliorative role of didymin (DDM) against TCDD-induced testicular toxicity.

METHODS

Forty-eight male Sprague-Dawley rats were divided into four equal groups (n=12). (i) Control group, (ii) TCDD-induced group was provided with 10 μg/kg/day of TCDD, (iii) TCDD + DDM group received 10 μg/kg/day of TCDD and 2 mg/kg/day of DDM, and (iv) DDM-treated group was administered with 2 mg/kg/day of DDM. After 56 days of treatment, biochemical, steroidogenic, hormonal, spermatogenic, apoptotic, and histopathological parameters were estimated.

RESULTS

TCDD affected the biochemical profile by reducing the activities of antioxidant enzymes, while increasing the levels of malondialdehyde (MDA) and reactive oxygen species (ROS). Furthermore, it decreased the expressions of steroidogenic enzymes, 3β-hydroxysteroid dehydrogenase (HSD), 17β-HSD, steroidogenic acute regulatory protein (StAR), cholesterol side-chain cleavage enzyme (CYP11A1), and 17α-hydroxylase/17, 20-lyase (CYP17A1), as well as reduced the levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), and plasma testosterone. Besides, epididymal sperm count, viability, and motility were decreased, while sperm morphological anomalies were increased. Moreover, TCDD altered the apoptotic profile by up-regulating the expressions of Bax and caspase-3, while downregulated the Bcl-2 expression. Additionally, histopathological damages were prompted due to TCDD administration. However, DDM restored all the TCDD-induced damages owing to its antioxidant, anti-apoptotic, and androgenic potential.

CONCLUSION

Our data suggested that DDM might play its role as a therapeutic agent against TCDD-prompted testicular toxicity.

Altered Energy Metabolism, Mitochondrial Dysfunction, and Redox Imbalance Influencing Reproductive Performance in Granulosa Cells and Oocyte During Aging

Female fertility decreases during aging. The development of effective therapeutic strategies to address the age-related decline in oocyte quality and quantity and its accurate diagnosis remain major challenges. In this review, we summarize our current understanding of the study of aging and infertility, focusing primarily on the molecular basis of energy metabolism, mitochondrial function, and redox homeostasis in granulosa cells and oocytes, and discuss perspectives on future research directions. Mitochondria serve as a central hub sensing a multitude of physiological processes, including energy production, cellular redox homeostasis, aging, and senescence. Young granulosa cells favor glycolysis and actively produce pyruvate, NADPH, and other metabolites. Oocytes rely on oxidative phosphorylation fueled by nutrients, metabolites, and antioxidants provided by the adjacent granulosa cells. A reduced cellular energy metabolism phenotype, including both aerobic glycolysis and mitochondrial respiration, is characteristic of older female granulosa cells compared with younger female granulosa cells. Aged oocytes become more susceptible to oxidative damage to cells and mitochondria because of further depletion of antioxidant-dependent ROS scavenging systems. Molecular perturbations of gene expression caused by a subtle change in the follicular fluid microenvironment adversely affect energy metabolism and mitochondrial dynamics in granulosa cells and oocytes, further causing redox imbalance and accelerating aging and senescence. Furthermore, recent advances in technology are beginning to identify biofluid molecular markers that may influence follicular development and oocyte quality. Accumulating evidence suggests that redox imbalance caused by abnormal energy metabolism and/or mitochondrial dysfunction is closely linked to the pathophysiology of age-related subfertility.

Consequences of Exposure to Hypobaric Hypoxia Associated with High Altitude on Spermatogenesis and Seminal Parameters: A Literature Review

Preclinical research has provided compelling evidence indicating that exposure to hypobaric hypoxia (HH) results in a deterioration of spermatogenesis. This adverse effect extends to the underlying molecular mechanisms, progressively leading to impairments in the seminiferous epithelium and germ cells and alterations in semen parameters. Indeed, several studies have demonstrated that animals exposed to HH, whether in natural high-altitude environments or under simulated hypoxic conditions, exhibit damage to the self-renewal and differentiation of spermatogenesis, an increase in germline cell apoptosis, and structural alterations in the seminiferous tubules. One of the primary mechanisms associated with the inhibition of differentiation and an increase in apoptosis among germ cells is an elevated level of oxidative stress, which has been closely associated with HH exposure. Human studies have shown that individuals exposed to HH, such as mountaineers and alpinists, exhibit decreased sperm count, reduced motility, diminished viability, and increased sperm with abnormal morphology in their semen. This evidence strongly suggests that exposure to HH may be considered a significant risk factor that could elevate the prevalence of male infertility. This literature review aims to provide a comprehensive description and propose potential mechanisms that could elucidate the infertility processes induced by HH. By doing so, it contributes to expanding our understanding of the challenges posed by extreme environments on human physiology, opening new avenues for research in this field.

Minerals and the Menstrual Cycle: Impacts on Ovulation and Endometrial Health

The role of minerals in female fertility, particularly in relation to the menstrual cycle, presents a complex area of study that underscores the interplay between nutrition and reproductive health. This narrative review aims to elucidate the impacts of minerals on key aspects of the reproductive system: hormonal regulation, ovarian function and ovulation, endometrial health, and oxidative stress. Despite the attention given to specific micronutrients in relation to reproductive disorders, there is a noticeable absence of a comprehensive review focusing on the impact of minerals throughout the menstrual cycle on female fertility. This narrative review aims to address this gap by examining the influence of minerals on reproductive health. Each mineral's contribution is explored in detail to provide a clearer picture of its importance in supporting female fertility. This comprehensive analysis not only enhances our knowledge of reproductive health but also offers clinicians valuable insights into potential therapeutic strategies and the recommended intake of minerals to promote female reproductive well-being, considering the menstrual cycle. This review stands as the first to offer such a detailed examination of minerals in the context of the menstrual cycle, aiming to elevate the understanding of their critical role in female fertility and reproductive health.

Phytochemical Screening, Antioxidant Effect and Sperm Quality of the Bomba ceiba Stamen Extracts on Charolais Cattle Sperm Induced by Ferrous Sulfate

Orange Bombax ceiba (B. ceiba) is an indigenous plant, and its stamen is an important ingredient in traditional Lanna food. There are limitations in scientific reports on the effects of the biological activities of B. ceiba stamens on the male reproductive system. This study aims to investigate the phytochemical compounds of the orange B. ceiba stamen and its potential effect on the antioxidant properties and quality of cattle sperm treated with Fe. The orange BUE had the highest total phenolics, total tannins, total monomeric anthocyanins, and maximal antioxidant potential. The orange BAE had the highest concentration of total flavonoids. LC-QTOF/MS showed that the orange BUE contained the highest number of phytochemical compounds related to male reproductive enhancement. The orange BUE enhanced sperm motility, and both the orange BUE and the BAE enhanced sperm viability and normal sperm morphology via free radical scavenging. It might be suggested that B. ceiba stamens have benefits for sperm preservation, sperm quality, and increasing the economic value of local plants, and that they may be developed and used to guard against oxidative stress from cryodamage induced by frozen semen technology.

BNC1 deficiency induces mitochondrial dysfunction-triggered spermatogonia apoptosis through the CREB/SIRT1/FOXO3 pathway: the therapeutic potential of nicotinamide riboside and metformin†

Male infertility is a global health problem that disturbs numerous couples worldwide. Basonuclin 1 (BNC1) is a transcription factor mainly expressed in proliferative keratinocytes and germ cells. A frameshift mutation of BNC1 was identified in a large Chinese primary ovarian insufficiency pedigree. The expression of BNC1 was significantly decreased in the testis biopsies of infertile patients with nonobstructive azoospermia. Previous studies have revealed that mice with BNC1 deficiency are generally subfertile and undergo gradual spermatogenic failure. We observed that apoptosis of spermatogonia is tightly related to spermatogenic failure in mice with a Bnc1 truncation mutation. Such impairment is related to mitochondrial dysfunction causing lower mitochondrial membrane potential and higher reactive oxygen species. We showed that downregulation of CREB/SIRT1/FOXO3 signaling participates in the above impairment. Administration of nicotinamide riboside or metformin reversed mitochondrial dysfunction and inhibited apoptosis in Bnc1-knockdown spermatogonia by stimulating CREB/SIRT1/FOXO3 signaling. Dietary supplementation with nicotinamide riboside or metformin in mutated mice increased SIRT1 signaling, improved the architecture of spermatogenic tubules, inhibited apoptosis of the testis, and improved the fertility of mice with a Bnc1 truncation mutation. Our data establish that oral nicotinamide riboside or metformin can be useful for the treatment of spermatogenic failure induced by Bnc1 mutation.

Involvement of Nrf2-PPAR-γ signaling in Coenzyme Q10 protecting effect against methotrexate-induced testicular oxidative damage

Studies have identified Coenzyme Q10 (CoQ10) as a promising agent in improving idiopathic male infertility; however, its role in chemically or environmentally induced testicular dysfunction is not well-established. We investigated the potential of CoQ10 to attenuate methotrexate (MTX)-induced testicular damage and to identify molecular targets of CoQ10 effects. Wistar rats received a single intraperitoneal dose of 20 mg/kg MTX on the fifth day of the 10-day experimental protocol. 100 mg/kg CoQ10 was given orally daily for ten days, alone or combined with MTX. The testes of MTX-treated animals showed thickened tunica albuginea, distortion of seminiferous tubules with a marked reduction of germinal lining, a few primary spermatocytes with no spermatozoa, apoptotic cells, congested sub-capsular and interstitial blood vessels, and interstitial edema. Reduction of reproductive hormones and increased oxidative, inflammatory, and apoptotic biomarkers levels were also seen in the MTX-treated rats. CoQ10 + MTX-treated rats were protected against MTX-induced testicular histological changes and showed improvement in testosterone, luteinizing-, and follicle-stimulating hormone serum levels compared to the MTX group. The testes of the CoQ10 + MTX-treated rats showed reduced malondialdehyde, myloperoxidase, tumor necrosis factor -α, interleukin-6 and -1β and Bax: Bcl2 ratio and enhanced glutathione, and catalase compared to MTX alone. CoQ10 enhanced MTX-induced downregulation of Nrf2 and PPAR-γ signaling and modulated its downstream targets, the inducible nitric oxide synthase, NF-κB, Bax, and Bcl2. In conclusion, CoQ10 targeted the Nrf2-PPAR-γ signaling loop and its downstream pathways, mitigating MTX-induced oxidative stress-related damages and alleviating the testicular dysfunction MTX caused. Our data suggest Nrf2-PPAR-γ signaling as a potential therapeutic target in testicular toxicity, where oxidative stress, inflammation, and apoptosis trigger damage.

Astragalus polysaccharide alleviates polycystic ovary syndrome by reducing insulin resistance and oxidative stress and increasing the diversity of gut microbiota

BACKGROUND

Polycystic ovary syndrome (PCOS) is a common reproductive endocrine disorder, which is frequently accompanied by insulin resistance, oxidative stress (OS), and dyslipidemia. Astragalus polysaccharide (APS)-as a water-soluble heteropolysaccharide-can lower blood sugar and lipid and exert anti-aging effects and thus has been proven to be beneficial to various types of metabolic diseases. However, specific mechanisms of the action of APS on PCOS are yet to be studied.

METHODS

Herein, BALB/C female mice aged 3 weeks were randomly divided into three groups (10 mice/group): oil + PBS group, DHEA + PBS group, and DHEA + APS group. Changes in the estrous cycle, ovarian tissue sections, serum levels of the hormone, blood glucose, blood lipid, and OS were studied. The intestinal microbiome was sequenced and Spearman correlation analysis was used to analyze the correlation between serum metabolic indexes and microflora.

RESULTS

The results revealed that APS treatment ameliorated insulin resistance, OS, and dyslipidemia in PCOS mice. The results of 16S rDNA sequencing indicated that there were significant differences in the composition and diversity of intestinal microorganisms between DHEA and APS treatments. Firmicutes, Lachnospiraceae, Bacilli, Lactobacillaceae, and Lachnospiraceae_NK4A13_group were abundant in the oil + PBS group. Bacteroidota and Muribaculaceae were enriched in the DHEA + PBS group, while Rikenellaceae, Odoribacter, and Marinifilaceae were enriched in the DHEA + APS group. Furthermore, Spearman correlation analysis showed that there were close interactions and correlations between intestinal bacteria and indicators of blood glucose, blood lipids, steroid hormones, and OS in PCOS mice.

CONCLUSIONS

Overall, the study showed that APS improved PCOS in mice by correcting serum metabolic disorders and increasing microbiome diversity, which may provide insight into understanding the pathogenesis and be a beneficial intervention for PCOS.

Ursonic acid attenuates spermatogenesis in oligozoospermia mice through inhibiting ferroptosis

Ursonic acid (UNA) is a natural pentacyclic triterpene found in some medicinal plants and foods. The reproductive protective effect of UNA was evaluated in a mouse model of oligozoospermia induced by busulfan (BUS) at 30 mg/kg b.w.. The mice were initially divided into groups with UNA concentrations of 10, 30, 50, 100 mg/kg. Subsequently, based on sperm parameters, the optimal concentration of 50 mg/kg was identified. As a control, an additional group was supplemented with ursolic acid at a concentration of 50 mg/kg. The results indicated that BUS caused the loss of spermatogenic cells in testis, the decrease of sperm in epididymis, the disorder of testicular cytoskeleton, the decrease of serum sex hormones such as testosterone which induced an increase in feedback of androgen receptor and other testosterone-related proteins, the increase of malondialdehyde and reactive oxygen species levels and the increase of ferroptosis in testis while UNA successfully reversed these injuries. High-throughput sequencing revealed that UNA administration significantly upregulated the expression of genes associated with spermatogenesis, such as Tnp1, Tnp2, Prm1, among others. These proteins are crucial in the histone to protamine transition during sperm chromatin remodeling. Network pharmacology analysis reveals a close association between UNA and proteins related to the transformation of histones to protamine. Molecular docking studies reveal that UNA can interact with the ferroptosis-inhibiting gene SLC7A11, thereby modulating ferroptosis. Taken together, UNA alleviated BUS-induced oligozoospermia by regulating hormone secretion, mitigating oxidative stress and promoting recovery of spermatogenesis by inhibiting the ferroptosis.

Cadmium as a male reproductive toxicant and natural and non-natural ways to tackle it: a review

Cadmium (Cd) is a naturally occurring environmental pollutant, a toxic substance that causes oxidative stress. According to epidemiological studies, the data suggested that environmental and occupational Cd exposure may be related to several diseases and severe testicular damage. However, studies are going on to explore the mechanism of Cd-induced male reproductive toxicity and its treatment strategies. Currently, researchers are focusing on naturally occurring bioactive compounds, plant extracts, and biochemical, which have better efficacy, less toxicity, and high bioavailability. This review focuses on the mechanistic effect of Cd on testicular toxicity and different categories of compounds having a beneficial impact on Cd-induced male reproductive toxicity. Some potent bioactive antioxidants are quercetin, caffeic acid phenethyl ester, cyanidin-3-O-glucoside, curcumin, and silymarin. In comparison, plant extracts are Costus afer leaf methanol extract, methanol root extract of Carpolobia lutea, red carrot methanolic extract, Panax ginseng extract, and biochemicals including melatonin, progesterone, glutamine, L-carnitine, and selenium. Advanced and more detailed studies are needed on these compounds to explore their mechanism in attenuating Cd-induced testicular toxicity and can be potential therapeutics in the future.

Mechanism and impact of heavy metal-aluminum (Al) toxicity on male reproduction: Therapeutic approaches with some phytochemicals

Heavy metals are ubiquitous environmental toxicants that have been known to have a serious effect on human and animal health. Aluminum (Al) is a widely distributed metal in nature. Al exposure has a detrimental impact on human fertility. This review focused on Al-induced male reproductive toxicity and the potential therapeutic approaches with some phytochemicals. Data from the literature showed that Al exposure is accompanied by a drastic decline in blood levels of FSH, LH, and testosterone, reduced sperm count, and affected sperm quality. Al exposure at high levels can cause oxidative stress by increasing ROS and RNS production, mediated mainly by downregulating Nrf2 signaling. Moreover, several investigations demonstrated that Al exposure evoked inflammation, evidenced by increased TNF-α and IL-6 levels. Additionally, substantial evidence concluded the key role of apoptosis in Al-induced testicular toxicity mediated by upregulating caspase-3 and downregulating Bcl2 protein. The damaging effects of Al on mitochondrial bioenergetics are thought to be due to the excessive generation of free radicals. This review helps to clarify the main mechanism involved in Al-associated testicular intoxication and the treatment strategy to attenuate the notable harmful effects on the male reproductive system. It will encourage clinical efforts to target the pathway involved in Al-associated testicular intoxication.

Mitochondrial function and reactive oxygen species production during human sperm capacitation: Unraveling key players

Sperm capacitation is a critical process for male fertility. It involves a series of biochemical and physiological changes that occur in the female reproductive tract, rendering the sperm competent for successful fertilization. The precise mechanisms and, specifically, the role of mitochondria, in sperm capacitation remain incompletely understood. Previously, we revealed that in mouse sperm mitochondrial activity (e.g., oxygen consumption, membrane potential, ATP/ADP exchange, and mitochondrial Ca2+ ) increases during capacitation. Herein, we studied mitochondrial function by high-resolution respirometry (HRR) and reactive oxygen species production in capacitated (CAP) and non-capacitated (NC) human spermatozoa. We found that in capacitated sperm from normozoospermic donors, the respiratory control ratio increased by 36%, accompanied by a double oxygen consumption rate (OCR) in the presence of antimycin A. Extracellular hydrogen peroxide (H2 O2 ) detection was three times higher in CAP than in NC sperm cells. To confirm that H2 O2 production depends on mitochondrial superoxide (O 2 · - $$ {\mathrm{O}}_2^{\cdotp -} $$ ) formation, we evaluated mitochondrial aconitase (ACO2) amount, activity, and role in the metabolic flux from the sperm tricarboxylic acid cycle. We estimated that CAP cells produce, on average by individual, (59 ± 22)% moreO 2 · - $$ {\mathrm{O}}_2^{\cdotp -} $$ in the steady-state compared to NC cells. Finally, we analyzed two targets of oxidative stress: lipid peroxidation by western blot against 4-hydroxynonenal and succinate dehydrogenase (SDH) activity by HRR. We did not observe modifications in lipoperoxidation nor the activity of SDH, suggesting that during capacitation, the increase in mitochondrial H2 O2 production does not damage sperm and it is necessary for the normal CAP process.

Extracellular vesicles in the treatment of oxidative stress injury: global research status and trends

Objective: The aim of this study was to conduct a bibliometric analysis of the literature on "Extracellular Vesicles in the Treatment of Oxidative Stress Injury" and to reveal its current status, hot spots and trends. Methods: The relevant literature was obtained from the Web of Science Core Collection (WoSCC) on 29 April 2023. We performed clustering and partnership analysis of authors, institutions, countries, references and keywords in the literature through CiteSpace software and the bibliometric online analysis platform and mapped the relevant knowledge maps. Results: A total of 1,321 relevant publications were included in the bibliometric analysis, with the number of publications in this field increasing year by year. These included 944 "articles" and 377 "reviews". The maximum number of publications published in China is 512, and the maximum number of highly cited publications published in the United States is 20. Based on CiteSpace, the country collaboration network map shows close and stable collaboration among high-productivity countries. Based on WoSCC, there are 1706 relevant research institutions and 119 highly cited elite institutions, among which Kaohsing Chang Gung Men Hosp has the most extensive influence. Studies related to "Extracellular Vesicles in the Treatment of Oxidative Stress Injury" have been published in 548 journals. The keywords of the publications show the main research areas and breakthroughs. Based on WoSCC, the keywords of the research area "Extracellular Vesicles in the Treatment of Oxidative Stress Injury" were found to be as follows: exosome(s), extracellular vesicle(s), oxidative stress, inflammation, mesenchymal stem cells, apoptosis, microRNA (miRNA), mitochondria, biomarker, autophagy, angiogenesis and Alzheimer's disease. Analysis showed that "mesenchymal stem cells", "microRNA", "autophagy", "histology" and "therapeutic" emerged as highly explosive keywords. Conclusion: This study is the first to use visual software and data mining to assess the literature in the field of "Extracellular Vesicles in the Treatment of Oxidative Stress Injury". The research history, research status and direction in this field provide a theoretical basis for its scientific research.