Analysis of lipid peroxidation in human spermatozoa using BODIPY C11

Protective effects of alpha-lipoic acid and alagebrium chloride against testicular dysfunction induced by varicocele and advanced glycation end (AGE) - Rich diet in a rat mode

Heat stress from varicocele can heighten oxidative stress in the testes, impacting sperm function and male fertility. Antioxidant therapy is explored as a remedy for varicocele, while dietary factors like processed foods, sugar, and saturated fats correlate with male infertility. Advanced glycation end products (AGEs), generated through glycation processes, can provoke oxidative stress, inflammation, and adverse health consequences. Alpha-lipoic acid (ALA), a versatile antioxidant, may alleviate oxidative stress and counteract the impact of AGEs, potentially by enhancing glucose reabsorption. Alagebrium chloride (ALT711), an anti-AGE compound, exhibits promise in cardiovascular disease by disrupting AGE cross-links. This study investigates the effects of ALA and ALT-711 on testicular function in varicocele and AGEs animal models. Both AGE and varicocele were found to alter the natural trends, leading to abnormal patterns in sperm parameters, testicular functional tests, as well as the expression of CML, RAGE, and TNF-α proteins. However, the administration of ALA or ALT711 helped mitigate these effects. While ALA demonstrated a slightly greater overall benefit compared to ALT, the difference was not statistically significant.

DMT1 knockout abolishes ferroptosis induced mitochondrial dysfunction in C. elegans amyloid β proteotoxicity

Iron is critical for neuronal activity and metabolism, and iron dysregulation alters these functions in age-related neurodegenerative disorders, such as Alzheimer's disease (AD). AD is a chronic neurodegenerative disease characterized by progressive neuronal dysfunction, memory loss and decreased cognitive function. AD patients exhibit elevated iron levels in the brain compared to age-matched non-AD individuals. However, the degree to which iron overload contributes to AD pathogenesis is unclear. Here, we evaluated the involvement of ferroptosis, an iron-dependent cell death process, in mediating AD-like pathologies in C. elegans. Results showed that iron accumulation occurred prior to the loss of neuronal function as worms age. In addition, energetic imbalance was an early event in iron-induced loss of neuronal function. Furthermore, the loss of neuronal function was, in part, due to increased mitochondrial reactive oxygen species mediated oxidative damage, ultimately resulting in ferroptotic cell death. The mitochondrial redox environment and ferroptosis were modulated by pharmacologic processes that exacerbate or abolish iron accumulation both in wild-type worms and worms with increased levels of neuronal amyloid beta (Aβ). However, neuronal Aβ worms were more sensitive to ferroptosis-mediated neuronal loss, and this increased toxicity was ameliorated by limiting the uptake of ferrous iron through knockout of divalent metal transporter 1 (DMT1). In addition, DMT1 knockout completely suppressed phenotypic measures of Aβ toxicity with age. Overall, our findings suggest that iron-induced ferroptosis alters the mitochondrial redox environment to drive oxidative damage when neuronal Aβ is overexpressed. DMT1 knockout abolishes neuronal Aβ-associated pathologies by reducing neuronal iron uptake.

DMT1 knockout abolishes ferroptosis induced mitochondrial dysfunction in C. elegans amyloid β proteotoxicity

Iron is critical for neuronal activity and metabolism, and iron dysregulation alters these functions in age-related neurodegenerative disorders, such as Alzheimer's disease (AD). AD is a chronic neurodegenerative disease characterized by progressive neuronal dysfunction, memory loss and decreased cognitive function. AD patients exhibit elevated iron levels in the brain compared to age-matched non-AD individuals. However, the degree to which iron overload contributes to AD pathogenesis is unclear. Here, we evaluated the involvement of ferroptosis, an iron-dependent cell death process, in mediating AD-like pathologies in C. elegans. Results showed that iron accumulation occurred prior to the loss of neuronal function as worms age. In addition, energetic imbalance was an early event in iron-induced loss of neuronal function. Furthermore, the loss of neuronal function was, in part, due to increased mitochondrial reactive oxygen species mediated oxidative damage, ultimately resulting in ferroptotic cell death. The mitochondrial redox environment and ferroptosis were modulated by pharmacologic processes that exacerbate or abolish iron accumulation both in wild-type worms and worms with increased levels of neuronal amyloid beta (Aβ). However, neuronal Aβ worms were more sensitive to ferroptosis-mediated neuronal loss, and this increased toxicity was ameliorated by limiting the uptake of ferrous iron through knockout of divalent metal transporter 1 (DMT1). In addition, DMT1 knockout completely suppressed phenotypic measures of Aβ toxicity with age. Overall, our findings suggest that iron-induced ferroptosis alters the mitochondrial redox environment to drive oxidative damage when neuronal Aβ is overexpressed. DMT1 knockout abolishes neuronal Aβ-associated pathologies by reducing neuronal iron uptake.

Effect of Advanced Glycation end Products (AGEs) on Sperm Parameters and Function in C57Bl/6 Mice

This study investigated the deleterious impact of advanced glycation end products (AGEs), commonly present in metabolic disorders like diabetes, obesity, and infertility-related conditions, on sperm structure and function using a mouse model where AGE generation was heightened through dietary intervention. Five-week-old C57BL/6 mice were divided into two groups, one on a regular diet (control) and the other on an AGE-rich diet. After 13 weeks, various parameters were examined, including fasting blood glucose, body weight, food consumption, sperm parameters and function, testicular superoxide dismutase levels, malondialdehyde content, total antioxidant capacity, Johnson score, AGE receptor (RAGE) content, and carboxymethyl lysine (CML) content. The results showed that mice in the AGE group exhibited increased body weight and elevated fasting blood glucose levels. Furthermore, the AGE group displayed adverse effects on sperm, including reduced sperm counts, motility, increased morphological abnormalities, residual histone, protamine deficiency, sperm DNA fragmentation, reduced testicular antioxidant capacity, and higher levels of RAGE and CML proteins. These findings underscore the negative impact of AGEs on male reproductive health, particularly within the context of metabolic disorders, emphasizing the crucial role of the AGE/RAGE axis in male infertility, especially in the context of Western dietary patterns.

Supplementation of sperm cryopreservation media with H2S donors enhances sperm quality, reduces oxidative stress, and improves in vitro fertilization outcomes

Cryopreservation of sperm can cause oxidative stress and damage, leading to decreased different functional parameters and fertilization potential. In this study, we evaluated two types of H2S donors: NaHS, a fast-releasing donor, and GYY4137, a slow-releasing donor during cryopreservation of goat sperm. Initially, we determined that 1.5 and 3 μM NaHS, and 15 and 30 μM GYY4137 are optimal concentrations that improved different sperm functional parameters including motility, viability, membrane integrity, lipid peroxidation, and ROS production during incubation at 38.5 °C for 90 min. We subsequently evaluated the impact of the optimal concentration of NaHS and GYY4137 supplementation on various functional parameters following thawing during cryopreservation. Our data revealed that supplementation of extender improved different parameters including post-thaw sperm motility, viability, membrane integrity, and reduced DNA damage compared to the frozen-thawed control group. The supplementation also restored the redox state, decreased lipid peroxidation, and improved mitochondrial membrane potential in the thawed sperm. Finally, we found that supplementation of the extender with NaHS and GYY4137 enhanced IVF outcomes in terms of blastocyst rate and quality of blastocysts. Our results suggest that both donors can be applied for cryopreservation as antioxidants to improve sperm quality and IVF outcomes of frozen-thawed goat sperm.

A nine-month repeat-dose intravaginal ring (Ovaprene) irritation study in sheep

OBJECTIVES

Ovaprene is a novel, investigational, intravaginal hormone-free monthly ring contraceptive designed for use in women of reproductive age to be worn over multiple weeks (one menstrual cycle). The objective of this work was to evaluate the safety of Ovaprene during a nine-month repeat-dose sheep study.

STUDY DESIGN

In addition to traditional safety endpoints such as histopathological evaluation of the sheep female reproductive tract, vaginal fluids were collected and tested for released iron over time. Also, the amount of iron in the rings was assessed following removal, and serum iron levels were measured. There were four sheep in each group (Ovaprene group and sham group).

RESULTS

There were no macroscopic clinical findings. There was minimal to mild, mixed or mononuclear cell infiltration present in all levels of vagina (cranial, mid, and caudal) from all animals including sham controls based on post-study necropsy. The female reproductive tract from animals treated with the Ovaprene ring was comparable to the sham controls. The concentrations of serum iron in sheep treated with Ovaprene ring were similar compared to a sham treated animal. The average amount of ferrous gluconate released from Ovaprene over the 29-day period of use was 175 mg of the approximately 512 mg nominally loaded into the rings.

CONCLUSIONS

Overall, the Ovaprene devices were well-tolerated in female sheep.

IMPLICATIONS

This study should support a chronic (e.g., one year) contraceptive efficacy study in women.

The influence of lifestyle and biological factors on semen variability

PURPOSE

Semen parameters are subjected to within-individual variability over time. The driving factors for this variability are likely multi-factorial, with healthier lifestyle associated with better semen quality. The extent in which variations in individual's lifestyle contributes to within-individual semen variability is unknown.

METHODS

A total of 116 repeat semen samples from 29 men aged 19-37 over 6 months were collected. Basic semen analysis as per 5th WHO manual and extended semen parameters (sperm DNA fragmentation, redox potential and lipid peroxidation, sperm binding to hyaluronan and hyperactive motility) were assessed. An additional 39 lifestyle/biological factors (weight, blood pressure, etc.) were collected at each sample including validated health questionnaires SF36 Health Status, Australian Recommend Food Score, and International Physical Activity Questionnaire.

RESULTS

Only 10 out of the 39 lifestyle factors varied within men across samples including age (P = 0.0024), systolic blood pressure (P = 0.0080), social functioning (P = 0.0340), energy (P = 0.0069), non-alcoholic caffeinated beverages (P = 0.0010), and nutrition (P < 0.0001). The only semen parameter that varied between collections was sperm morphology (coefficient of variation 23.8 (6.1-72.0), P < 0.05). We only observed weak (r < 0.3) to moderate (r > 0.3- < 0.6) correlations between lifestyle factors, including body mass index, waist circumference, nutrition, exercise, blood pressure and semen parameters including sperm count, progressive motility, and sperm DNA fragmentation (P < 0.05).

CONCLUSION

In healthy men from the general population, semen quality and associated lifestyle factors do not significantly vary over 6 months, indicating that one semen sample is likely sufficient for determining male fertility in this population.

AOP Report: Glutathione Conjugation Leading to Reproductive Dysfunction via Oxidative Stress

We propose an adverse outcome pathway (AOP) for reproductive dysfunction via oxidative stress (OS). The AOP was developed based on Organisation for Economic Co-operation and Development (OECD) Guidance Document 184 and on the specific considerations of the OECD users' handbook supplement to the guidance document for developing and assessing AOPs (no. 233). According to the qualitative and quantitative experimental data evaluation, glutathione (GSH) conjugation is the first upstream key event (KE) of this AOP to reproductive dysfunction triggering OS. This event causes depletion of GSH basal levels (KE2 ). Consequently, this drop of free GSH induces an increase of reactive oxygen species (KE3 ) generated by the natural cellular metabolic processes (cellular respiration) of the organism. Increased levels of these reactive species, in turn, induce an increase of lipid peroxidation (KE4 ). This KE consequently leads to a rise in the amount of toxic substances, such as malondialdehyde and hydroxynonenal, which are associated with decreased quality and competence of gamete cell division, consequently impairing fertility (KE5 and adverse outcome). The overall assessment of the general biological plausibility, the empirical support, and the essentiality of KE relationships was considered as high for this AOP. We conclude that GSH conjugation is able to lead to reproductive disorder in fishes and mammals, via OS, but that the amount of stressor needed to trigger the AOP differs between stressors. Environ Toxicol Chem 2023;42:2519-2528. © 2023 SETAC.

The role of the transsulfuration pathway in spermatogenesis of vitamin D deficient mice

Vitamin D deficiency is a global health problem and has been linked to defective spermatogenesis and male infertility. In this study, we aimed to investigate the main enzymes involved in the transsulfuration pathway of 1-carbon metabolism, and spermatogenesis function. Therefore, sixteen male C57 mice were addressed to a control (standard diet) or vitamin D deficient (VDD) diet for 14 weeks. The results show that compared to the standard diet, VDD increased final body weight and reduced sperm quality, caused damage to the testicular structure, and decreased the serum levels of testosterone. In addition, serum concentrations of homocysteine, vitamin B12, and sperm oxidative stress markers increased. In testicular tissues, the CBS and CSE protein levels were down-regulated whereas HO-1 was up-regulated at both mRNA and protein expression levels. Within a mice deprivation model, VDD deeply suppressed testosterone and impaired spermatogenesis with oxidative stress-mediated mechanisms. The effects of the deprivation appeared to be at least in part independent of genomic and receptor-mediated vitamin D actions and suggest a specific impairment of the alternative transsulfuration pathway.

MiOXSYS® and OxiSperm® II assays appear to provide no clinical utility for determining oxidative stress in human sperm-results from repeated semen collections

BACKGROUND

Oxidative stress in semen contributes up to 80% of all infertility diagnosis. Diagnostics to measure oxidative stress in semen was recently added to the 6th edition WHO methods manual, although diagnostic predictive values need to be interpreted with caution as there are still several research questions yet to be answered.

OBJECTIVES

To determine the natural fluctuations in semen redox indicators (MiOXSYS® and OxiSperm® II) within and between men and their association with markers of sperm oxidative stress.

MATERIALS AND METHODS

Total, 118 repeat semen samples from 31 generally healthy men aged 18-45 years, over 6 months. Standard semen analysis as per 5th WHO manual. Semen redox levels measured via MiOXSYS® and OxiSperm® II. Additional attributes of sperm quality; HBA® binding assay and sperm hyperactivation and oxidative stress; DNA fragmentation (Halo® Sperm) and lipid peroxidation (BODIPY™ 581/591 C11) were assessed.

RESULTS

Samples with high redox-potential (MiOXSYS® ≥1.47 sORP/106 sperm/ml) had lower sperm, motility, morphology and higher DNA fragmentation (P < 0.05). Upon further analysis, these associations were driven solely by the adjustment of sperm concentration (106 /ml) in normalised redox-potential. No significant associations between NBT-reactivity (OxiSperm® II) and measures of the sperm function or oxidative stress were observed (P > 0.05). Fluctuations in semen redox levels varied greater between men than within men over the study period.

DISCUSSION

Neither MiOXSYS® nor OxiSperm® II assays were predictive of sperm function or sperm oxidative stress. This was likely due at least in part to limited understanding of their biochemistry and clinical application. As a result, these assays seem to provide no additional clinical utility beyond that of a standard semen analysis, highlighting the imperative for the development of new robust point-of-care devices for accurately determining sperm oxidative stress.

CONCLUSION

These findings suggest that MiOXSYS® and OxiSperm® II systems for the measurement of sperm oxidative stress may have limited diagnostic potential.

In Vitro and In Vivo Studies on the Efficacy of Zinc-Oxide and Selenium Nanoparticle in Cryopreserved Goat (Capra hircus) Spermatozoa

Different nanoparticles (NPs) are currently being investigated for their potential role as cryoprotectant during semen cryopreservation in several mammalian species. It may be possible to improve semen quality following cryopreservation by supplementation of NPs in the freezing extenders. The present study was carried out in semen collected from four (4) Assam Hill Goat bucks (10 ejaculates per buck) to investigate the effect of supplementing zinc oxide (ZnO) and selenium (Se) NPs in Tris-citric acid-fructose yolk (TCFY) extender on in vitro sperm quality and in vivo fertility rate after freeze-thawing. The size morphology and zeta potential of ZnO and Se NPs were evaluated prior to its incorporation in the freezing extender. Qualified semen samples (> 70% progressive motility) were divided into five (5) aliquots and then diluted in TCFY extender containing ZnO and Se NP supplementation at different concentrations (T0, control; T1, 0.1 mg/mL ZnO NPs; T2, 0.5 mg/mL ZnO NPs; T3, 0.5 µg/mL Se NPs; and T4, 1 µg/mL Se NPs). Diluted semen was packed in 0.25 mL straws and then stored in liquid nitrogen. After thawing, post-thaw in vitro sperm attributes were evaluated. Finally, the effect of NPs on in vivo fertility rate was checked in heat-synched does (n = 70) by artificial insemination (AI) using straws that showed superior results during the in vitro study. Results showed that ZnO and Se NPs were poly-crystalline in nature with particle size below 100 nm (nm). The evaluated post-thaw sperm in vitro attributes were significantly (p < 0.001) higher in T1 in comparison to T0. The antioxidant enzyme activities were significantly (p < 0.001) higher in T1. Lipid peroxidation (LPO) profile was significantly (p < 0.001) lower in T1. Sperm motility and mitochondrial membrane potential (MMP) had a highly significant (r = 0.580, p < 0.05) association in T1. No significant (p > 0.05) differences in pregnancy rates were recorded after AI in the different treatments. In conclusion, extender supplemented with 0.1 mg/mL ZnO NPs improved post-thaw semen quality of goat spermatozoa consequently by increasing activities of endogenous antioxidant enzymes thereby lowering LPO levels. However, improved in vitro outcomes might not correspond to improved field fertility outcomes.

Seminal quality comparison of first and second cryopreserved ejaculates of Alpine kid goats by flow cytometry

Discarding the first ejaculate is recommended as an alternative for improving seminal quality after long sexual resting, especially when semen should be used for cryopreservation. However, when the males are not in sexual resting the necessity to discarding the first ejaculate is still unknown. Therefore, this study aimed to compare by flow cytometry the quality of the first and second ejaculates. Ten kids and uniform goats between 5 and 6 months of age were used in a completely randomized design. Semen collection was carried out every 4 days, until a total of five ejaculates per animal in each treatment was completed. The fresh and frozen semen collected were processed and analyzed using macroscopic and microscopic parameters, resistance test, hypo-osmotic medium test, and flow cytometry (FC). The FC parameters were production of reactive oxygen species, plasma and acrosomal membrane integrity, and lipid peroxidation of the plasma membrane. The ejaculates did not differ for the resistance test, the reactivity in the hypo-osmotic medium and for the macroscopic and microscopic seminal parameters, except for sperm volume and concentration. The first ejaculate had a higher percentage of minor and total defects. None of the FC parameters analyzed differed between the first and second ejaculates. The first and second ejaculates demonstrated similar seminal qualities, so for Alpine kid goats without a sexual resting period, discarding the first ejaculate it is not recommended.

Ameliorating effect of Mucuna pruriens seed extract on sodium arsenite-induced testicular toxicity and hepato-renal histopathology in rats

Background and Aim

A significant cause of arsenic poisoning is polluted groundwater. Arsenic poisoning results in the suppression of spermatogenesis and the liver and kidneys are vulnerable to the toxic effects as well. Mucuna pruriens has been identified to have fertility-enhancing and anti-lipid peroxidation properties. Based on these properties of M. pruriens, this study aimed to investigate the efficacy of M. pruriens seed extract in reducing sodium arsenite-induced testicular impairment and hepato-renal histopathology in rats.

Materials and Methods

The study was divided into two groups; short-term (45 days) and long-term (90 days) treatment groups and each group was divided into nine subgroups. Subgroups 1 and 2 served as normal and N-acetyl cysteine (NAC) controls, respectively. Subgroups 3-9 received sodium arsenite in the drinking water (50 mg/L). Subgroup-4 received NAC (210 mg/kg body weight [BW]) orally once daily. Subgroups 5-7 received aqueous seed extract of M. pruriens (350, 530, and 700 mg/kg BW, respectively) orally once daily. Subgroups 8 and 9 received a combination of NAC and aqueous seed extract (350 and 530 mg/kg BW, respectively) orally once daily. Following the treatment, animals were sacrificed and sperm parameters and DNA damage were evaluated. Testis, liver, and kidneys were analyzed for histopathology.

Results

Sodium arsenite-induced a significant reduction in sperm parameters and increase in the abnormal architecture of spermatozoa. Histology revealed tissue necrosis. The M. pruriens seed extract ameliorated the damaging effects of sodium arsenite with respect to tissue architecture and sperm parameters when coadministered.

Conclusion

Mucuna pruriens has beneficial effects against the deleterious effects of sodium arsenite on various tissues. Thus, M. pruriens (530 and 700 mg/kg BW) supplementation would reduce the adverse changes observed with sodium arsenite exposure.

Male infertility and somatic health - insights into lipid damage as a mechanistic link

Over the past decade, mounting evidence has shown an alarming association between male subfertility and poor somatic health, with substantial evidence supporting the increased incidence of oncological disease, cardiovascular disease, metabolic disorders and autoimmune diseases in men who have previously received a subfertility diagnosis. This paradigm is concerning, but might also provide a novel window for a crucial health reform in which the infertile phenotype could serve as an indication of potential pathological conditions. One of the major limiting factors in this association is the poor understanding of the molecular features that link infertility with comorbidities across the life course. Enzymes involved in the lipid oxidation process might provide novel clues to reconcile the mechanistic basis of infertility with incident pathological conditions. Building research capacity in this area is essential to enhance the early detection of disease states and provide crucial information about the disease risk of offspring conceived through assisted reproduction.

Oocyte quality assessment in marine invertebrates: a novel approach by fluorescence spectroscopy

Background

The assessment of oocyte quality is, nowadays, a major challenge in aquaculture, oocyte cryopreservation, and environmental science. Oocyte quality is a determining factor in fertilization and embryo development; however, there is still a lack of rapid and sensitive cellular markers for its assessment. Currently, its estimation is predominantly based on morphological analysis, which is subjective and does not consistently reflect the developmental competence of the oocytes. Despite several recent studies investigating molecular markers related to oocyte quality, methods currently available for their determination pose various technical challenges and limitations. In this study, we developed a novel approach based on fluorescence spectroscopy to assess different intrinsic physiological parameters that can be employed to evaluate egg quality in marine invertebrates that are widely used as animal models such as sea urchins and mussels.

Results

Different physiological parameters, such as viability, mitochondrial activity, intracellular ROS levels, plasma membrane lipid peroxidation, and intracellular pH, for egg quality evaluation have been successfully assessed in sea urchins and mussels by using specific fluorescent dyes and detecting the fluorescent signals in eggs through fluorescence spectroscopy.

Conclusions

Based on our findings, we propose these physiological markers as useful predictors of egg quality in marine invertebrates; they can be estimated rapidly, selectively, and sensitively by employing this novel approach, which, due to the speed of analysis, the low cost, and easy use can be considered a powerful analytical tool for the egg quality assessment.

Iodine Supplementation Improved Antioxidant Status, Hormonal Status, Sexual Behavior, and Semen Production Performance of Bos indicus Bulls Under Tropical Climatic Condition

Iodine is anessential micronutrient that plays a crucial role in male reproduction (sexual behavior and semen production performance) by modulating thyroid function and the antioxidant status of the animal. Nonetheless, in Bos indicus bulls, a thorough evaluation of the effects of dietary iodine supplementation on antioxidant status, seminal quality parameters, and its interaction with other minerals is not documented. Twelve Bos indicus (Sahiwal) bulls were distributed into three groups (n = 4 in each group) viz. T₁ (control), T₂, and T₃ and fed diets containing 0.250, 0.375, and 0.500 ppm iodine/ kg dry matter intake, corresponding to 0%, 50%, and 100% higher than ICAR (2013) recommendations, respectively. The experimental feeding was carried out for 60 days and the effects on nutrient utilization, hormonal and antioxidant status, and sperm function tests were investigated. Results revealed that body weight, dry matter intake, and nutrient digestibility remained unaffected by dietary supplementation of iodine. Testosterone and thyroxine hormone concentrations were improved (p<0.05) in T₂ and T₃ groups. Blood and seminal iodine content were also higher (p<0.05) in both the supplemented groups (T₂ and T₃). Sperm functions viz. viability, physical membrane integrity, acrosomal integrity, motility, and mitochondrial membrane potential were improved (p<0.05) due to iodine supplementation. Furthermore, lipid peroxidation and membrane scrambling in spermatozoa were reduced (p<0.05) in T₂ and T₃ groups. Blood antioxidant status (total antioxidant activity and GPx levels) was improved (p<0.05) in T₂ and T₃. Sexual behavior was also improved (p<0.05) in iodine-supplemented groups. Hence, it can be concluded that iodine supplementation at the dose rate of 0.500 ppm in the Bos indicus bull diet is beneficial in improving hormonal status, antioxidant status, and semen quality.

Overlapping sperm damages from vitamin B or D deficiency in mice: Insights into the role of clinical supplementations

In this study, the effect of 14 weeks of standard diet (controls) or folate and vitamin B12-free diet (VBD group) or vitamin D-free diet (VDD group) were assessed on mice testicular function, and sperm function. Vitamin D deprivation caused increased body weight with no effect from VBD confirming the calcium-independent role of vitamin D on body weight homeostasis. The two deprivations caused convergent damages including decreased testosterone, worsened Johnson scores, tubular differentiation index and spermatogenesis index, and serious worsening of sperm parameters and of sperm functional tests (DNA methylation, protamination, DNA damage and lipid peroxidation). From a metabolic point of view, the damage from both models converged on the one carbon cycle (methylations) and the transsulfuration pathway (GSH and antioxidant defences) and increased circulating homocysteine, although with different mechanisms: VBD appeared to hamper methylations due to lower ability to regenerate homocysteine to methionine whereas VDD appeared to interfere with homocysteine transsulfuration to cysteine and, thereafter, GSH. VDD also caused a huge paradox increase of vitamin B12, which was likely in a non-functional form and warrants further investigation. These findings strongly endorse the potential benefit of combined folate/B12 and vitamin D supplementation in infertile patients.

Possible Implications of Bacteriospermia on the Sperm Quality, Oxidative Characteristics, and Seminal Cytokine Network in Normozoospermic Men

This study focused on the identification of bacterial profiles of semen in normozoospermic men and their possible involvement in changes to the sperm structural integrity and functional activity. Furthermore, we studied possible fluctuations of selected cytokines, oxidative markers, and antibacterial proteins as a result of bacterial presence in the ejaculate. Sperm motility was assessed with computer-assisted sperm analysis, while sperm apoptosis, necrosis and acrosome integrity were examined with fluorescent methods. Reactive oxygen species (ROS) generation was quantified via luminometry, sperm DNA fragmentation was evaluated using the TUNEL protocol and chromatin-dispersion test, while the JC-1 assay was applied to evaluate the mitochondrial membrane potential. Cytokine levels were quantified with the biochip assay, whilst selected antibacterial proteins were quantified using the ELISA method. The predominant species identified by the matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry were Staphylococcus hominis, Staphylococcus capitis and Micrococcus luteus. The results revealed that the sperm quality decreased proportionally to the increasing bacterial load and occurrence of conditionally pathogenic bacteria, including Enterococcus faecalis, Staphylococcus aureus and Escherichia coli. Antimicrobial susceptibility tests revealed a substantial resistance of randomly selected bacterial strains to ampicillin, vancomycin, tobramycin, and tetracycline. Furthermore, an increased bacterial quantity in semen was accompanied by elevated levels of pro-inflammatory cytokines, including interleukin-1, interleukin-2, interleukin-6, tumor necrosis factor alpha as well as ROS overproduction and lipid peroxidation of the sperm membranes. Our results suggest that semen quality may be notably affected by the bacterial quantity as well as quality. It seems that bacteriospermia may be associated with inflammatory processes, oxidative stress, sperm structural deterioration, and a subsequent risk for the development of subfertility, even in normozoospermic males.

Molecular analysis of microorganisms in the semen and their impact on semen parameters

OBJECTIVE

Chronic genitourinary infections can alter male fertility and even promote carcinogenic processes. This study aimed to evaluate the effect of the presence in the semen of microorganisms on semen quality.

MATERIALS AND METHODS

Clinical symptoms and conventional and functional seminal parameters of eleven fertile donors and ten volunteers with prostatitis-like symptoms were evaluated. Nitric oxide, antioxidant capacity, and pro-inflammatory cytokines in semen and seminal plasma samples were also quantified. Finally, the expression of the ROR-γT, FoxP3, and T-bet genes in semen and the presence of DNA of microorganisms associated with prostatitis in urine and semen were evaluated.

RESULTS

When compared with fertile donors, volunteers with chronic prostatitis-like symptoms reported erectile dysfunction (0% vs. 10%, p = 0.2825) and premature ejaculation (0% vs. 40%; p = 0.0190). No statistically significant differences were observed in seminal parameters, cytokine measurement, antioxidant capacity, nitric oxide concentration and ROR-γT, FoxP3, T-bet. Microorganisms responsible for sexually transmitted infections and some bacteria associated with the microbiota and infections in the prostate gland were detected. In the semen from the subjects with prostatitis-like symptoms T. vaginalis DNA was detected; in addition, N. gonorrhoeae DNA was also detected in semen and urine samples. S. pyogenes was detected in the urine samples from the control group.

CONCLUSIONS

Prostatitis-like symptoms are a common finding in young men that affect sexual and reproductive health, but not always the seminal parameters or fertility. The presence of prostatitis- like symptoms does not affect seminal quality. However, it appears to be associated with an increased likelihood of erectile dysfunction and premature ejaculation. Thus, affecting the quality of life and sexual and reproductive health.

Effect of over dilution of semen with tris extender on motion and functional attributes of bull spermatozoa during cryopreservation

The present study was aimed to evaluate the effect of over dilution of semen with tris extender on motion and functional attributes of bull sperm post-thaw. Ejaculates (n = 24; mass motility ≥3+) were collected from bulls (n = 4) using artificial vagina, diluted to 20, 15, 10 and 5 million spermatozoa/0.25 ml, and cryopreserved. The results revealed that total motility (%), progressive motility (%) and rapid motility (%), straight linear velocity (μm/s), straightness (%) reduced significantly (p < 0.05) when semen was diluted to 5 million sperm concentration. Among the various sperm function attributes, proportions of live spermatozoa, acrosome intact spermatozoa, hypo-osmotic swelling responsive spermatozoa and non-capacitated spermatozoa reduced (p < 0.05) in 5 million spermatozoa, and the proportions of moribund spermatozoa, dead spermatozoa, live acrosome reacted spermatozoa, dead acrosome intact spermatozoa, capacitated spermatozoa and spermatozoa with lipid peroxidation increased significantly (p < 0.05) when semen was diluted from 20 to 5 million. However, the over-dilution of semen did not affect slow motility, dead acrosome reacted spermatozoa, sperm protamine deficiency and spermatozoa with lipid peroxidation. In conclusion, the over dilution of semen affected sperm motion and functional attributes of frozen-thawed bull semen.

Measuring Reactive Oxygen Species in Semen for Male Preconception Care: A Scientist Perspective

Oxidative stress and elevated levels of seminal and sperm reactive oxygen species (ROS) may contribute to up to 80% of male infertility diagnosis, with sperm ROS concentrations at fertilization important in the development of a healthy fetus and child. The evaluation of ROS in semen seems promising as a potential diagnostic tool for male infertility and male preconception care with a number of clinically available tests on the market (MiOXSYS, luminol chemiluminescence and OxiSperm). While some of these tests show promise for clinical use, discrepancies in documented decision limits and lack of cohort studies/clinical trials assessing their benefits on fertilization rates, embryo development, pregnancy and live birth rates limit their current clinical utility. In this review, we provide an update on the current techniques used for analyzing semen ROS concentrations clinically, the potential to use of ROS research tools for improving clinical ROS detection in sperm and describe why we believe we are likely still a long way away before semen ROS concentrations might become a mainstream preconception diagnostic test in men.

Chronic Prostatitis: Impact of Lifestyle, Infection, and Inflammation on Semen Parameters

Chronic prostatitis is a widespread disease of the prostate affecting men’s sexual and reproductive health worldwide. Its leading causes are urogenital tract infections by microorganisms with a prostate tropism. This study aimed to evaluate semen parameters and the factors associated (lifestyle, urogenital infections, and inflammation) with the onset of chronic prostatitis symptoms. This case-control study included seventy-six donors: 30 volunteers with chronic prostatitis and 46 asymptomatic volunteers for urogenital infections as a control group. Sociodemographic, urinary symptoms, pain location, sexual and reproductive health and lifestyle-related variables were collected in a survey. Seminal quality, cytokine levels in semen and serum, and the presence of nineteen microorganisms in the urogenital tract were evaluated. Prostatitis was also associated with poor sperm morphology, more lipoperoxidation of the sperm membrane, and lower serum nitric oxide concentration. In addition, N. gonorrhoeae infection was detected more frequently in semen samples from volunteers with chronic prostatitis. Volunteers with chronic prostatitis report more frequently erectile dysfunction and premature ejaculation, anxiety, depression, and stress compared to the control group. Chronic prostate infections alter the microbiota from the genitourinary tract causing prostatitis, a disease that affects all life areas, including the familiar environment of patients. Chronic prostatitis affects seminal parameters, with a great impact on life quality and sexual and reproductive health. Despite being a relatively unexplored disease, much remains to be clarified regarding its diagnosis and treatment. Alterations in the genitourinary microbiota can favor sexually transmitted infections that produce chronic and systemic inflammation.

Deciphering the Nexus Between Oxidative Stress and Spermatogenesis: A Compendious Overview

Oxidative stress (OS) and reactive oxygen species (ROS) are one of the main reasons for the multifactorial concern - male infertility. ROS are active components of cellular metabolism that are intrinsic to cellular functioning and are present at minimal and unreactive levels in normal cells. They are an integral component of the sperm developmental physiology, capacitation, and function. As said "anything in excess is poison," so is the case with ROS. These, when produced in excess to the antioxidants present in the seminal plasma, cause multiple malformations during the process of spermatogenesis such as lipid peroxidation, interfere with capacitation, sperm DNA fragmentation and damage to the membrane of the sperm which in turn reduces the motility of the sperm and its ability to fuse with the oocyte. Exposure of spermatozoa to oxidative stress is a major causative agent of male infertility. Thus, a delicate balance between the beneficial and detrimental effects of ROS for proper functions is of utter importance. In this chapter, the influence of ROS in OS which is a key player in male infertility along with the diagnosis, available treatment, and prevention of extensive ROS buildup within the spermatozoa are highlighted.

The Impact of Bacteriocenoses on Sperm Vitality, Immunological and Oxidative Characteristics of Ram Ejaculates: Does the Breed Play a Role?

Bacterial contamination of semen is an often overlooked, yet important, factor contributing to decreased sperm vitality. Understanding the impact of bacterial presence on sperm structural integrity and functional activity may assist the development of effective strategies to prevent, or manage, bacteriospermia in the breeding practice. The aim of this study was to describe the bacterial profiles of ram semen (n = 35), and we also focused on the associations between bacteriospermia, sperm structure, and function, as well as oxidative and inflammatory characteristics of semen. For a better insight, the samples were divided into three groups, according to the breeds used in the study: native Wallachian (NW), improved Wallachian (IW), and Slovak dairy (SD) breeds. The results showed a significantly lower motility and membrane integrity in the NW group in comparison to the IW and SD groups, which was accompanied by a significantly higher concentration of leukocytes, increased reactive oxygen species (ROS) generation, and subsequent oxidative insults to the sperm lipids and proteins. Accordingly, the NW group presented with the highest bacterial load, in which Staphylococcus and Escherichia were the predominant representatives. The Pearson correlation analysis uncovered positive relationships amongst the bacterial load and leukocytospermia (r = 0.613), the extent of lipid peroxidation (r = 0.598), protein oxidation (r = 0.514), and DNA fragmentation (r = 0.638). Furthermore, positive correlations were found between the bacterial load and pro-inflammatory molecules, such as the C-reactive protein (r = 0.592), interleukin 1 (r = 0.709), and interleukin 6 (r = 0.474), indicating a possible involvement of the immune response in the process of bacteriospermia. Overall, our data indicate that ram semen quality may be equally affected by the bacterial load and diversity. Furthermore, we can assume that the presence of bacteria in ejaculates triggers inflammatory processes, causes ROS overproduction, and, thereby, contributes to alterations in the sperm structure, while at the same time compromising the fertilization ability of male gametes.

The Sixth Edition of the WHO Manual for Human Semen Analysis: A Critical Review and SWOT Analysis

Semen analysis is the cornerstone of male fertility evaluation with WHO guidelines providing the basis for procedural standardization and reference values worldwide. The first WHO manual was published in 1980, and five editions have been subsequently released over the last four decades. The 6th Edition was published in July 2021. In this review, we identify the key changes of this 6th Edition. Additionally, we evaluate the utility of this 6th Edition in clinical practice using SWOT (strengths, weaknesses, opportunities, and threats) analysis. This new Edition has made the analysis of basic semen parameters more robust, taking into account the criticisms and grey areas of the previous editions. The tests assessing sperm DNA fragmentation and seminal oxidative stress are well-described. The main novelty is that this latest edition abandons the notion of reference thresholds, suggesting instead to replace them with “decision limits”. While this seems attractive, no decision limits are proposed for either basic semen parameters, or for extended or advanced parameters. This critical review of the 6th Edition of the WHO laboratory manual combined with a SWOT analysis summarizes the changes and novelties present in this new Edition and provides an in-depth analysis that could help its global use in the coming years.

Effect of curcumin, and nano-curcumin on sperm function in varicocele rat model

Varicocele is one of the most important causes of infertility in men which gradually leads to testicular dysfunction. Testicular heat stress-induced oxidative stress is considered the main cause of pathology in these individuals. In this study, the effects of curcumin and nano-curcumin, as natural antioxidants, were investigated on spermatogenesis and sperm function in varicocele-induced rats. Seventy Wistar rats were randomly divided into seven groups; sham, control, varicocele, varicocele + curcumin 50 mg, varicocele + curcumin 100 mg, varicocele + nano-curcumin 4 mg and varicocele + nano-curcumin 8 mg. After 2 months of antioxidant therapy, all the rats were sacrificed. The results demonstrated that the mean sperm concentration and motility were significantly lower while the mean of abnormal morphology, lipid peroxidation, intracytoplasmic ROS and DNA damage was significantly higher in varicocelised rats compared to control and sham groups (p < .05). Both doses of curcumin and also nano-curcumin were significantly effective in improving the aforementioned parameters except for abnormal sperm morphology, and motility where nano-curcumin (4 mg) was significantly more effective than other groups (p < .05). The results of the current study suggest the application of nano-curcumin is more preferable to curcumin in infertile individuals with varicocele.

Detection of lipid peroxidation in dog spermatozoa with the fluorescent dye C11-BODIPY581/591

C11-BODIPY^581/591 is a fluorescent probe that has been successfully used to evaluate lipid peroxidation in different species, but it has not been completely studied in the dog. Thus, the aim of the present study was to assess lipid peroxidation of dog spermatozoa using C11-BODIPY^581/591 and compare different positive controls of the technique. Twenty-four ejaculates were collected from 8 adult male dogs. Routine seminal characteristics were evaluated in raw semen. Lipid peroxidation evaluation was performed as described in other species. Samples were divided in three aliquots, exposed to UV radiation, incubated with hydrogen peroxide or left without treatment (control). Lipid peroxidation was significantly greater only in UV-exposed samples than in the control ones (91 ± 6% vs. 8.3 ± 3.5%, p ˂ .01). In conclusion, C11-BODIPY^581/591 is useful to evaluate lipid peroxidation of dog spermatozoa and UV radiation is a good promoter of membrane oxidation, so irradiated samples can be used as a positive control of this technique.

Microbiota, Prostatitis, and Fertility: Bacterial Diversity as a Possible Health Ally

Background

In health, microorganisms have been associated with the disease, although the current knowledge shows that the microbiota present in various anatomical sites is associated with multiple benefits.

Objective

This study aimed to evaluate and compare the genitourinary microbiota of chronic prostatitis symptoms patients and fertile men.

Materials and Methods

In this preliminary study, ten volunteers have included 5 volunteers with symptoms of chronic prostatitis (prostatitis group) and five fertile volunteers, asymptomatic for urogenital infections (control group) matched by age. Bacterial diversity analysis was performed using the 16S molecular marker to compare the microbiota present in urine and semen samples from chronic prostatitis symptoms and fertile volunteers. Seminal quality, nitric oxide levels, and seminal and serum concentration of proinflammatory cytokines were quantified.

Results

Fertile men present a greater variety of operational taxonomical units-OTUs in semen (67.5%) and urine (17.6%) samples than chronic prostatitis symptoms men. Chronic prostatitis symptoms men presented a higher concentration of IL-12p70 in seminal plasma. No statistically significant differences were observed in conventional and functional seminal parameters. The species diversity in semen samples was similar in healthy men than prostatitis patients, inverted Simpson index median 5.3 (5.0–10.7) vs. 4.5 (2.1–7.8, p=0.1508). Nevertheless, the microbiota present in the semen and urine samples of fertile men presents more OTUs. Less microbial diversity could be associated with chronic prostatitis symptoms. The presence of bacteria in the genitourinary tract is not always associated with the disease. Understanding the factors that affect the microbiota can implement lifestyle habits that prevent chronic prostatitis.

Conclusion

Chronic prostatitis does not seem to affect male fertility; however, studies with a larger sample size are required. Our preliminary results strengthen the potential role; the greater bacterial diversity is a protective factor for chronic prostatitis.

Assessment of MUSASHI 1 and MUSASHI 2 expression in spermatozoa and testicular tissue

MUSASHI (MSI) family plays the main role in the spermatogenesis process. The purpose of this study was the assessment of sperm MSI1 and MSI2, and sperm functional tests in infertile men (n = 30) with varicocele and fertile men (n = 30). Furthermore, MSI1 and MSI2 proteins were assessed in testicular tissue of azoospermic men (n = 9) as well as epididymal spermatozoa and testis of mice. Expression of MSI1 and MSI2 was assessed at RNA and protein levels in human spermatozoa. Sperm concentration and motility were significantly lower, while abnormal sperm morphology, lipid peroxidation, DNA fragmentation and protamine deficiency were significantly higher in men with varicocele compared to fertile individuals. Any significant difference was not observed in the expression of MSI1 and MSI2 mRNA between the two groups. Unlike MSI1 protein that was not detectable in humans, the relative expression of MSI2 protein was similar in varicocele and fertile individuals. The expression level of both Msi1 and Msi2 proteins was also observable in mouse spermatozoa. No significant relationship was observed between sperm functional parameters with expression of these genes. The data of this study demonstrated that although MSI1 and MSI2 play important roles during spermatogenesis, their relative expression in spermatozoa was not affected by varicocele.

Sperm Motility, Oxidative Status, and Mitochondrial Activity: Exploring Correlation in Different Species

Sperm quality assessment is the first step for evaluating male fertility and includes the estimation of sperm concentration, motility, and morphology. Nevertheless, other parameters can be assessed providing additional information on the male reproductive potential. This study aimed to evaluate and correlate the oxidative status, mitochondrial functionality, and motility in spermatozoa of two marine invertebrate (Ciona robusta and Mytilus galloprovincialis) and one mammalian (Bos taurus) species. By combining fluorescent staining and spectrofluorometer, sperm oxidative status was evaluated through intracellular reactive oxygen species (ROS) and plasma membrane lipid peroxidation (LPO) analysis. Mitochondrial functionality was assessed through the mitochondrial membrane potential (MMP). In the three examined species, a negative correlation emerged between sperm motility vs ROS levels and LPO. Sperm motility positively correlated with MMP in bovine, whereas these parameters were not related in ascidian or even negatively related in mussel spermatozoa. MMP was negatively related to ROS and LPO levels in ascidians, only to LPO in bovine, and positively related in mussel spermatozoa. These results suggest that energy sources for sperm motility vary between species and that ROS causes a decline in sperm motility via oxidative damage of membrane lipids. Overall, this study validates the use of fluorescent probes in combination with spectrofluorometer as a simple and powerful methodology for supplementary evaluation of sperm quality shedding light on new potential quality markers and provided relevant information on sperm energetic metabolism.

Does maternal exposure to nicotine affect the oocyte quality and reproductive capacity in adult offspring?

Gonadal development begins in the intrauterine phase and females from most species are born with an established oocyte reserve. Exposure to drugs during gestation can compromise the offspring health, also affecting the gametes quality. Nicotine, the main component of cigarettes, is an oxidant agent capable of altering the fertility in men and women. As female gametes are susceptible to oxidative stress, this drug can damage the oolemma and affect oocyte maturation, induce errors during chromosomal segregation and DNA fragmentation. Oocyte mitochondria are particularly susceptible to injuries, contributing to the oocyte quality loss and embryonic development disruption. Thus, considering the high number of women who smoke during pregnancy, while significant events are occurring in the embryo for future fertility of offspring, we seek to verify the quality of the oocytes from adult rats exposed to nicotine during intrauterine phase and breastfeeding. Pregnant Wistar rats received nicotine by osmotic mini-pumps and the female progenies were evaluated in adulthood for oocyte quality (viability, lipid peroxidation, generation of reactive oxygen species and mitochondrial integrity) and reproductive capacity. Embryos (3dpc) and fetuses (20dpc) generated by these rats were also evaluated. The results showed that the dose of 2 mg/kg/day of nicotine through placenta and breast milk does not affect the number of oocytes and the fertility capacity of adult rats. However, it causes some morphological alterations in oocytes, mitochondrial changes, embryonic fragmentation and disruption of fetal development. The malformations in fetuses generated from these gametes can also indicate the occurrence of epigenetic modifications.

Effect of Different High-Fat and Advanced Glycation End-Products Diets in Obesity and Diabetes-Prone C57BL/6 Mice on Sperm Function

Background:

We aimed to compare the effects of using high-fat (HF) and advanced glycation end-products (AGEs) containing diets to induce obesity and diabetes on sperm function in mice.

Materials and Methods:

In this experimental study, twenty-five 4-week old C57BL/6 mice were divided into 5 groups and were fed with control, 45% HF, 60% HF, 45% AGEs-HF, or 60% AGEs-HF diet. After 28 weeks, fast blood sugar, glucose intolerance, insulin concentration, homeostatic model assessments (HOMA) for insulin resistance (IR) and HOMA for beta cells (HOMA beta) from systematic blood were assessed. In addition, body weight, morphometric characteristics of testes, sperm parameters, DNA damage (AO), protamine deficiency (CMAA3), and sperm membrane (DCFH-DA) and intracellular (BODIPY) lipid peroxidation were measured.

Results:

Body mass and fasting blood sugar increased significantly in all experimental groups compared to the control group. Insulin concentration, glucose intolerance, HOMA IR, and HOMA beta were also increased significantly with higher levels of fat and AGEs in all four diets (P<0.05). The changes in the 60% HF-AGEs group, however, were more significant (P<0.001). Morphometric characteristics of the testis, sperm concentration, and sperm morphology in the diet groups did not significantly differ from the control group, while sperm motility and DNA damage in the 45%HF were significantly low. Although for protamine deficiency, both 60% HF-AGEs and 45% HF showed a significant increase compared to the control, the mean of sperm lipid in the 45% HF group and intracellular peroxidation in the 60% HF-AGEs group had the highest and the lowest increases, respectively.

Conclusion:

Our results, interestingly, showed that is the negative effects of a diet containing AGEs on examined parameters are less than those in HF diets. One possible reason is detoxification through the activation of the protective glyoxalase pathway as the result of the chronic AGEs increase in the body.

Comparative evidence support better antioxidant efficacy of mitochondrial-targeted (Mitoquinone) than cytosolic (Resveratrol) antioxidant in improving in-vitro sperm functions of cryopreserved buffalo (Bubalus bubalis) semen

The present study compared the effect of mitochondria-targeted (Mitoquinone, MitoQ) and untargeted cytosolic antioxidant (Resveratrol, RESV) supplementation on lipid peroxidation (LPO) and in-vitro sperm functions of cryopreserved buffalo bull semen. To optimize additive's concentration, sperm pellet obtained from twenty-four ejaculates was supplemented with different concentrations of MitoQ (20 nM, 100 nM, 200 nM); and RESV (10 μM, 25 μM, 50 μM) against control in the extender. The post-thaw sperm motility, livability, and membrane integrity were higher (P < 0.05) in 200 nM MitoQ and 50 μM RESV than other concentrations used. In another experiment, sperm pellet from thirty-two ejaculates was supplemented with 200 nM MitoQ and 50 μM RESV in the extender. Pre-freeze and post-thaw progressive motility and livability were higher (P < 0.05) in MitoQ (200 nM) than RESV (50 μM) treatment. MitoQ supplementation improved post-thaw membrane integrity (CFDA-PI) higher (P < 0.05) than RESV, however, hypo-osmotic swelling response observed no improvement with RESV treatment. Post-thaw LPO rate was lower (P < 0.05) and Bovine cervical mucus penetration was higher (P < 0.05) in MitoQ than RESV treatment. In post-thaw semen, MitoQ showed higher (P < 0.05) proportion of acrosome intact (FITC-PNA), live non-apoptotic (P < 0.01) sperm with a higher reduction (P < 0.05) in membrane scrambling. MitoQ improved (P < 0.01) proportion of sperm with high Mitochondrial Membrane Potential and low LPO (P < 0.01) than RESV treatment. In conclusion, improvement in post-thaw in-vitro sperm functions and cryo-tolerance was more evident in MitoQ than RESV supplemented buffalo bull semen. Our study provides a better strategy to mitigate oxidative stress by enhancing mitochondrial antioxidant system with targeted antioxidants than cytosolic antioxidant supplementation.

Advancing Semen Evaluation Using Lipidomics

Developing a deeper understanding of biological components of sperm is essential to improving cryopreservation techniques and reproductive technologies. To fully ascertain the functional determinants of fertility, lipidomic methods have come to the forefront. Lipidomics is the study of the lipid profile (lipidome) within a cell, tissue, or organism and provides a quantitative analysis of the lipid content in that sample. Sperm cells are composed of various lipids, each with their unique contribution to the overall function of the cell. Lipidomics has already been used to find new and exciting information regarding the fatty acid content of sperm cells from different species. While the applications of lipidomics are rapidly evolving, gaps in the knowledge base remain unresolved. Current limitations of lipidomics studies include the number of available samples to analyze and the total amount of cells within those samples needed to detect changes in the lipid profiles across different subjects. The information obtained through lipidomics research is essential to systems and cellular biology. This review provides a concise analysis of the most recent developments in lipidomic research. This scientific resource is important because these developments can be used to not only combat the reproductive challenges faced when using cryopreserved semen and artificial reproductive technologies in livestock such as cattle, but also other mammals, such as humans or endangered species.

Deferasirox, an Iron-Chelating Agent, Improves Testicular Morphometric and Sperm Functional Parameters in a Rat Model of Varicocele

Varicocele is characterized by testicular dysfunction that originates from hyperthermia and hypoxia, leading to defects in testicular tissue and altered spermatozoa structure and function. The varicocele testis is characterized by the presence of intracellular iron deposits that contribute to the associated oxidative stress. Therefore, we tested the hypothesis that administration of an iron-chelating agent, such as deferasirox (DFX), could potentially mitigate the consequences of varicocele on testicular tissue and spermatozoa. Using a well-established rat model of varicocele (VCL), we show that treatment with DFX partially improved the structure and function of the testis and spermatozoa. In particular, sperm motility was markedly restored whereas abnormal sperm morphology was only partially improved. No significant improvement in sperm count was observed that could be associated with the proapoptotic response observed following iron chelation treatment. No reduction in oxidative damage to spermatozoa was observed since lipid peroxidation and DNA integrity were not modified. This was suggested to be a result of increased oxidative stress. Finally, we also saw no indication of attenuation of the endoplasmic reticulum/unfolded protein (ER/UPR) stress response that we recently found associated with the VCL testis in rats.

Is ferroptosis involved in ROS-induced testicular lesions in a varicocele rat model?

BACKGROUND

Ferroptosis is an iron-dependent cell death that is distinct from apoptosis. Based on excessive amounts of iron and reactive oxygen species in varicocele (VCL) rats, we hypothesize that ferroptosis might be involved in VCL. In addition, since alpha-lipoic acid (ALA) was shown to have both antioxidant and anti-ferroptotic activity we assessed in the present work the status of ferroptosis in our varicocele model and the protective effect of ALA. To this end, 70 male Wistar rats were divided into 7 groups: control, sham and varicocele groups which were initially sacrificed 2 months after the operation to verify the induction of varicocele. A second batch of the same 3 groups were sacrificed 4 months after varicocele induction to evaluate the effect of ALA supplementation. The parameters measured were chromatin integrity (aniline blue and acridine orange staining), lipid peroxidation (BODIPY staining), testicular morphometry and iron content. In addition, redox (GSH and NADPH) and ferroptosis (Nrf2, Slc7a11, P53 and p-Jnk) markers were evaluated at 2 and 4 months post-operation.

RESULT

The alteration of the spermatic parameters made it possible to verify the induction of the varicocele. Iron accumulated well in the testicles during varicocele and decreased significantly following ALA treatment. Ferroptotic molecular markers at the mRNA and protein levels were not significantly altered. ALA supplementation did not alter NADPH values, but increased GSH levels.

CONCLUSION

Despite the increased accumulation of iron in the testes 2 and 4 months after surgical induction of varicocele, molecular evidence did not demonstrate the involvement of ferroptosis. This could be explained by the mosaic nature of the varicocele affecting some seminiferous tubules and not others which could mask variations in molecular markers. In parallel, our study confirms that ALA stimulates the NRF2 pathway.

Effect of Low-Intensity Endurance Training and High-Intensity Interval Training on Sperm Quality in Male Rats with Fatty Liver

Background

We aimed to investigate the effect of low-intensity endurance training (LIET) and high-intensity inter- val training (HIIT) on sperm parameters, chromatin status, and oxidative stress in a rat model of non-alcoholic fatty liver disease (NAFLD).

Materials and Methods

For this experimental study, we divided 40 male Wistar rats into four groups (control, sham, HIIT and LIET) according to diet treatment and exercise training protocol. Liver triglycerides, sperm parameters, sperm lipid peroxidation (BODIPY C11 probe) and chromatin status [chromomycin A3 (CMA3)], and acridine orange [AO] staining) were assessed in these groups at the end of the study.

Results

The mean liver triglyceride values significantly improved in both the LIET and HIIT groups compared to the control and sham groups. The mean of testicular volume, sperm concentration, motility, intensity of sperm lipid peroxidation and DNA damage were similar within groups. While, the mean percentage of sperm lipid peroxidation and protamine deficiency were significantly higher in the LIET and HIIT groups compared to the control group.

Conclusion

Both LIET and HIIT in the rat NAFLD model had no adverse effects on testicular morphometric param- eters, sperm concentration, motility, and DNA integrity. However, the mean sperm lipid peroxidation and protamine deficiency were significantly higher in both exercise groups. Our study suggests that exercise or antioxidant supple- mentation could minimise the adverse effects of oxidant by-products of exercise.

Synbiotic (FamiLact) administration in idiopathic male infertility enhances sperm quality, DNA integrity, and chromatin status: A triple-blinded randomized clinical trial

BACKGROUND

Idiopathic male infertility is often treated empirically. A recent body of evidence has indicated the association between pro ± prebiotics administration and improvement in semen parameters.

OBJECTIVE

To assess the effect of FamiLact (probiotic + prebiotic) administration on male subjects with idiopathic infertility.

MATERIALS AND METHODS

Fifty-six men with idiopathic male infertility were randomly/equally divided into two groups. Men in the case and control groups received 500 mg of FamiLact and an identical placebo for 80 days, respectively. A semen sample was obtained from each of the participants before initiation and after the termination of the treatment course. Samples underwent regular semen analysis and were further analyzed to assess the level of DNA damage (sperm chromatin structure assay), oxidative stress (BODIPY C11 staining), and protamine deficiency (chromomycin-A3 staining) in spermatozoa.

RESULTS

No significant difference was observed between the baseline values of both groups. After intervention, mean sperm concentration, motility, and normal morphology were significantly higher in the FamiLact group compared to the placebo group (p < 0.05). In the FamiLact receivers, we detected improvement regarding the following parameters: concentration, motility, abnormal morphology, sperm lipid peroxidation, and DNA fragmentation (p ≤ 0.02). Likewise, in the placebo group, we noticed a decrease in the post-medication mean value of DNA fragmentation (p = 0.03) while observing no significant difference regarding other parameters.

CONCLUSION

FamiLact administration improves sperm concentration, motility, and abnormal morphology and decrease sperm DNA damage, possibly through alleviating oxidative stress in the seminal fluid.

Melittin-induced metabolic changes on the Madin-Darby Bovine Kidney cell line

ABSTRACT In this study, the toxic effects of melittin on Madin-Darby Bovine Kidney cells (MDBK) were analyzed with respect to mitochondrial functionality by reduction of MTT and flow cytometry, apoptosis potential, necrosis, oxygen reactive species (ROS) production, lipid peroxidation, and DNA fragmentation using flow cytometry and cell membrane destabilization by confocal microscopy. The toxicity presented dose-dependent characteristics and mitochondrial activity was inhibited by up to 78.24 ±3.59% (P<0.01, n = 6) in MDBK cells exposed to melittin (10μg/mL). Flow cytometry analysis revealed that melittin at 2μg/mL had the highest necrosis rate (P<0.05) for the cells. The lipoperoxidation of the membranes was also higher at 2μg/mL of melittin (P<0.05), which was further confirmed by the microphotographs obtained by confocal microscopy. The highest ROS production occurred when the cells were exposed to 2.5μg/mL melittin (P<0.05), and this concentration also increased DNA fragmentation (P<0.05). There was a significative and positive correlation between the lipoperoxidation of membranes with ROS (R=0.4158), mitochondrial functionality (R=0.4149), and apoptosis (R=0.4978). Thus, the oxidative stress generated by melittin culminates in the elevation of intracellular ROS that initiates a cascade of toxic events in MDBK cells.

Transcriptomic Profiling of Buffalo Spermatozoa Reveals Dysregulation of Functionally Relevant mRNAs in Low-Fertile Bulls

Although, it is known that spermatozoa harbor a variety of RNAs that may influence embryonic development, little is understood about sperm transcriptomic differences in relation to fertility, especially in buffaloes. In the present study, we compared the differences in sperm functional attributes and transcriptomic profile between high- and low-fertile buffalo bulls. Sperm membrane and acrosomal integrity were lower (P < 0.05), while protamine deficiency and lipid peroxidation were higher (P < 0.05) in low- compared to high-fertile bulls. Transcriptomic analysis using mRNA microarray technology detected a total of 51,282 transcripts in buffalo spermatozoa, of which 4,050 transcripts were differentially expressed, and 709 transcripts were found to be significantly dysregulated (P < 0.05 and fold change >1) between high- and low-fertile bulls. Majority of the dysregulated transcripts were related to binding activity, transcription, translation, and metabolic processes with primary localization in the cell nucleus, nucleoplasm, and in cytosol. Pathways related to MAPK signaling, ribosome pathway, and oxidative phosphorylation were dysregulated in low-fertile bull spermatozoa. Using bioinformatics analysis, we observed that several genes related to sperm functional attributes were significantly downregulated in low-fertile bull spermatozoa. Validation of the results of microarray analysis was carried out using real-time qPCR expression analysis of selected genes (YBX1, ORAI3, and TFAP2C). The relative expression of these genes followed the same trend in both the techniques. Collectively, this is the first study to report the transcriptomic profile of buffalo spermatozoa and to demonstrate the dysregulation of functionally relevant transcripts in low-fertile bull spermatozoa. The results of the present study open up new avenues for understanding the etiology for poor fertility in buffalo bulls and to identify fertility biomarkers.

Mechanistic Insight into the Regulation of Lipoxygenase-Driven Lipid Peroxidation Events in Human Spermatozoa and Their Impact on Male Fertility

A prevalent cause of sperm dysfunction in male infertility patients is the overproduction of reactive oxygen species, an attendant increase in lipid peroxidation and the production of cytotoxic reactive carbonyl species such as 4-hydroxynonenal. Our previous studies have implicated arachidonate 15-lipoxygenase (ALOX15) in the production of 4-hydroxynonenal in developing germ cells. Here, we have aimed to develop a further mechanistic understanding of the lipoxygenase-lipid peroxidation pathway in human spermatozoa. Through pharmacological inhibition studies, we identified a protective role for phospholipase enzymes in the liberation of peroxidised polyunsaturated fatty acids from the human sperm membrane. Our results also revealed that arachidonic acid, linoleic acid and docosahexanoic acid are key polyunsaturated fatty acid substrates for ALOX15. Upon examination of ALOX15 in the spermatozoa of infertile patients compared to their normozoospermic counterparts, we observed significantly elevated levels of ALOX15 protein abundance in the infertile population and an increase in 4-hydroxynonenal adducts. Collectively, these data confirm the involvement of ALOX15 in the oxidative stress cascade of human spermatozoa and support the notion that increased ALOX15 abundance in sperm cells may accentuate membrane lipid peroxidation and cellular dysfunction, ultimately contributing to male infertility.

Apamin-induced alterations in J774 1.6 macrophage metabolism

ABSTRACT Among the immune system cells, macrophages have an important role. Apamin, a bee venom constituent, is important in the defense of these insects. Thus, we aimed to evaluate the metabolism of J774 1.6 macrophage cell line when exposed to isolated and purified apamin, using cytotoxicity tests by MTT reduction and analysis by flow cytometry (apoptosis / necrosis, production of reactive oxygen species (ROS), membranous lipoperoxidation (LPO), electrical potential of the mitochondrial membrane (mMP) and DNA fragmentation). None of the tested concentrations (10 to 100μg/mL) were cytotoxic according to MTT reductions. Apoptosis rates decreased at concentrations of 2.5, 5.0, and 10.0μg/mL (P<0.05), while necrosis rates increased (P<0.05). However, rates of healthy cells at the highest tested concentration (10μg/mL) did not differ from control (P>0.05). Apamin did not alter ROS, LPO, or DNA fragmentation. Therefore, all analyzed concentrations (1.25 to 10μg/mL) decreased mMP. Such decrease in apoptosis might be due to a suppression of mitochondrial pro-apoptotic messengers, as this peptide causes no oxidative stress, lipid peroxidation, and DNA damage. Highly sensitive techniques are majorly important for proper interpretation of cellular toxicity mechanisms, combined with routine laboratory methods.

The Male Is Significantly Implicated as the Cause of Unexplained Infertility

Male infertility is recognized as a relatively common, complex condition, generated by a broad array of environmental and genetic factors. Historical reliance on the conventional semen profile has tended to underestimate the true contribution of "the male factor" to human infertility. This review highlights the importance of genetic and epigenetic factors in the etiology of male infertility, identifying a range of mutations responsible for primary testicular failure and impaired fertilizing potential. More than three quarters of all de novo mutations arise in the male germline via mechanisms that involve the inefficient or defective repair of DNA damage. Understanding the range of factors capable of creating genetic turmoil in the paternal germline is essential, if we are to gain a deep understanding of the causes of male infertility, rather than just the symptoms that characterize its presence. High levels of DNA fragmentation induced by oxidative stress are part of this equation. Oxidative stress is, in turn, driven by biological (age, ejaculation frequency, varicocele, infection), lifestyle (smoking, obesity), and environmental factors (heat, other forms of electromagnetic radiation, and toxins) that can impair the fertilizing potential of the spermatozoa and influence the incidence of spontaneous mutations that may cause infertility in the offspring.

Spermatozoa produced during winter are superior in terms of phenotypic characteristics and oviduct explants binding ability in the water buffalo (Bubalus bubalis)

Although reduced reproductive efficiency during summer has been well documented in buffaloes, the reason for the same is yet to be understood. The present study was conducted to identify the subtle differences in sperm phenotypic characteristics (motility, membrane integrity, acrosome reaction and lipid peroxidation status), oviduct binding ability and expression of fertility-associated genes (AK 1, ATP5D, CatSper 1, Cytochrome P450 aromatase, SPP1 and PEBP1) between winter and summer seasons in buffaloes. Cryopreserved spermatozoa from 6 Murrah buffalo bulls (3 ejaculates/bull/season) were utilized for the study. Real-time quantitative PCR was performed for assessing the expression patterns of select fertility-associated genes. The proportion of motile and membrane intact spermatozoa was significantly higher (p < .05) in winter as compared to summer ejaculates. The proportion of moribund and lipid peroxidized spermatozoa was significantly lower (p < .05) in winter ejaculates as compared to summer. The sperm-oviduct binding index was significantly lower (p < .01) when spermatozoa from summer ejaculates were used as compared to winter ejaculates. The expression of fertility-associated genes did not differ significantly between the two seasons except for PEPB1; the transcriptional abundance of PEPB1 was significantly (p < .05) lower in summer as compared to winter season. It was inferred that buffalo spermatozoa produced during winter season were superior in terms of cryotolerance, membrane and acrosome integrity, lipid peroxidation status and the ability to bind with oviduct explants.

Capsaicin improves sperm quality in rats with experimental varicocele

Capsaicin is the main capsaicinoid in chilli peppers that have numerous biological and pharmaceutical roles in the body such as antioxidant, anti-inflammatory, anticarcinogenic, analgesic, counterirritant and antiarthritic properties. Numerous studies have shown increased oxidative stress in men with varicocele that is caused by dilation of the spermatic vein and increase of testicular temperature. Therefore, we aimed to assess the effect of Capsaicin on sperm parameters in rats with experimental varicocele. At first, we induced varicocele in 30 Wistar rats and, verify varicocele model only in 10 rats by assessment of sperm parameters, oxidative stress, DNA damage and persistent histone after 2 months. Of the remaining 20 varicocelised rats, half of them were treated with 2.5 mg/kg Capsaicin for two months and the other half served as control. Then, sperm tests were assessed, and the results showed that Capsaicin can restore the mean of sperm oxidative stress (38.78 ± 3.75 versus 58.37 ± 4.34; p < .05), sperm concentration (60.14 ± 7.66 versus 34.87 ± 5.78; p < .05) and motility (62.43 ± 3.10 versus 41.22 ± 5.11; p < .05) in varicocelised rats treated with Capsaicin compared to varicocelised rats that were not treat. Therefore, Capsaicin possibly with reduction of oxidative stress level could improve mean of sperm concentration and motility in varicocele condition.

From Sperm Motility to Sperm-Borne microRNA Signatures: New Approaches to Predict Male Fertility Potential

In addition to the paternal genome, spermatozoa carry several intrinsic factors, including organelles (e.g., centrioles and mitochondria) and molecules (e.g., proteins and RNAs), which are involved in important steps of reproductive biology such as spermatogenesis, sperm maturation, oocyte fertilization and embryo development. These factors constitute potential biomarkers of "viable sperm" and male fertility status and may become major assets for diagnosing instances of idiopathic male infertility in both humans and livestock animals. A better understanding of the mechanism of action of these sperm intrinsic factors in the regulation of reproductive and developmental processes still presents a major challenge that must be addressed. This review assembles the main data regarding morpho-functional and intrinsic sperm features that are associated with male infertility, with a particular focus on microRNA (miRNA) molecules.

Endoplasmic Reticulum Stress (ER Stress) and Unfolded Protein Response (UPR) Occur in a Rat Varicocele Testis Model

Using a surgically induced varicocele rat model, we show here strong evidence that the misfolded/unfolded protein response that is part of the stress response of the endoplasmic reticulum (ER) is activated in the varicocele testis (VCL), leading to the induction of apoptosis. To support this hypothesis, it is observed that the spliced variant of the X-box protein 1 (XBP1s), resulting from the activation of the inositol-requiring enzyme 1 (IRE1) membrane sensor, is significantly more represented in VCL testicular extracts. The activation of the IRE1/XBP1s pathway is also supported by the observation that the VCL testes show an increase phosphorylation of the c-Jun-kinase (JNK) known to be one intermediate of this pathway and an increased level of caspase-3, the terminal apoptotic effector, partly explaining the apoptotic status of the VCL testis.

Different approaches for assessing sperm function

Different approaches can be used to assess sperm function in different conditions, i.e. sperm storage, freezing-thawing or activation by induction of capacitation and acrosome reaction. In this review we will focus on the assays routinely performed in our laboratories, giving a literature support to critically analyse different approaches. In fact, researchers usually tend to look for the "one shot" parameter that could explain itself a specific process; it is our conviction that a multiparametric approach is still more valid, as some changes in sperm function are very complex and could be explained only by operating in different ways. Sperm motility, the most evident sperm characteristic, should be assessed by computer-aided sperm analysers that permit an objective evaluation of the motility and its kinematic parameters. Commercial and open source instruments are available and could be profitably used together with specific statistical approaches. The use of microscopy, and particularly fluorescent microscopy, could be a very useful tool to assess different parameters in sperm cells both by fluorophores that give indication of a determined function, and by immunolocalization of proteins, that permits the discover of new features or to explain particular sperm functions. The same substrates could be used also in flow cytometry: the difference is that it permits to study wider sperm populations (and their sub-population distribution). Flow cytometry is undergoing a very wide use in spermatology and technical and experimental rigor is needed to obtain reliable results. Metabolic assessment of sperm features, particularly energetic supply, ATP formation and other enzyme activities, could represent a very important challenge to acquire new information and complete/integrate those derived from other techniques. Finally, functional assays such as oocyte binding and in vitro fertilization, represent a very strong tool to assess sperm function in vitro, as they could evidence the functional intactness of some pathways.