The In Vitro Impact of the Herbicide Roundup on Human Sperm Motility and Sperm Mitochondria

Effects of glyphosate on sperm quality of the estuarine crab Neohelice granulata, under the "One Health" perspective

This study was aimed at evaluating the effects of the commercial formulation Roundup Ultramax® on sperm mortality and viability, in terms of the capacity of spermatozoids (spz) to trigger the acrosome reaction (AR), using the estuarine crab Neohelice granulata as a model. To this, an in vivo assay comprising 100 days duration was carried out, on a control group and two groups exposed to the formulation (0.01 mg/L and 0.2 mg/L of glyphosate) under controlled conditions of photoperiod, feeding, and temperature. At the end of the assay, the right vas deferens (VD, proximal and middle portion) was dissected, and after homogenizing it in calcium-free saline solution, the acrosome reaction was induced in the phase containing the spz. In each treatment, the percentage of spz with total and partial AR was calculated, as well as that of dead spz. Compared to the control, crabs exposed to the herbicide showed a significant decrease in spz with full AR, together with an increase in the percentage of spz with partial AR. Furthermore, spz mortality was significantly higher in both glyphosate concentrations compared to the control, in a concentration-dependent manner. On the other hand, abnormal spermatophores, showing expanded walls and coalescence, were observed in a significant percentage in the left VD of the groups treated with the herbicide. The results obtained are compared with those from other studies on several invertebrate and vertebrate species that found inhibition of the AR and abnormal sperm, together with inhibition of spermatogenesis, endocrine disruption, and reduced sperm motility by effect of pure glyphosate and/or different glyphosate formulations. In summary, the available evidence highlights the possible impact of glyphosate on sperm quality, in a wide variety of species.

The effects of a glyphosate-based herbicide on the bovine gametes during an in vitro embryo production model

Roundup® (R), while it is the most used herbicide globally, and its residues are ubiquitous in urban and suburban areas, its impact on vertebrates' safety remains highly debated. Here, in three in vitro experiments, we investigated the effects of a very low dose (1 ppm) of R on the fertilization capacity and embryo development in cattle. In the first experiment, frozen-thawed bull semen exposed to R for 1 h exhibited reduced motility parameters but unaffected fertilization ability. However, after in vitro fertilization, the rates of embryo formation were significantly lower compared to the untreated controls. In the second experiment, oocytes exposed to R during in vitro maturation showed reduced cleavage rates, and the embryo yield on days 7, 8, and 9 of embryo culture was significantly lower than that of the controls. In the third experiment, oocytes were matured in the presence of R and in a medium containing both R and Zinc, chosen to offer antioxidant protection to the oocytes. Day-7 blastocysts were analyzed for the expression of genes associated with oxidative stress, apoptosis, and epigenetic reprogramming. Exposure to R markedly suppressed embryo formation rates compared to the controls. The combination of R with Zinc restored the blastocyst yield, which on days 8 and 9 was comparable to that of the controls and higher than the groups exposed only to R on all days. The gene expression analysis revealed that R promotes oxidative stress development, triggers apoptosis, and induces epigenetic changes in developing embryos, while zinc presence alleviates these adverse effects of R. These findings imply that even at very low doses, R could be highly toxic, leading to functional abnormalities in both gametes, potentially affecting fertility in both genders.

Glyphosate: Hepatotoxicity, Nephrotoxicity, Hemotoxicity, Carcinogenicity, and Clinical Cases of Endocrine, Reproductive, Cardiovascular, and Pulmonary System Intoxication

Glyphosate (GLP) is an active agent of GLP-based herbicides (GBHs), i.e., broad-spectrum and postemergent weedkillers, commercialized by Monsanto as, e.g., Roundup and RangerPro formulants. The GBH crop spraying, dedicated to genetically engineered GLP-resistant crops, has revolutionized modern agriculture by increasing the production yield. However, abusively administered GBHs' ingredients, e.g., GLP, polyoxyethyleneamine, and heavy metals, have polluted environmental and industrial areas far beyond farmlands, causing global contamination and life-threatening risk, which has led to the recent local bans of GBH use. Moreover, preclinical and clinical reports have demonstrated harmful impacts of GLP and other GBH ingredients on the gut microbiome, gastrointestinal tract, liver, kidney, and endocrine, as well as reproductive, and cardiopulmonary systems, whereas carcinogenicity of these herbicides remains controversial. Occupational exposure to GBH dysregulates the hypothalamic-pituitary-adrenal axis, responsible for steroidogenesis and endocrinal secretion, thus affecting hormonal homeostasis, functions of reproductive organs, and fertility. On the other hand, acute intoxication with GBH, characterized by dehydration, oliguria, paralytic ileus, as well as hypovolemic and cardiogenic shock, pulmonary edema, hyperkalemia, and metabolic acidosis, may occur fatally. As no antidote has been developed for GBH poisoning so far, the detoxification is mainly symptomatic and supportive and requires intensive care based on gastric lavage, extracorporeal blood filtering, and intravenous lipid emulsion infusion. The current review comprehensively discusses the molecular and physiological basics of the GLP- and/or GBH-induced diseases of the endocrine and reproductive systems, and cardiopulmonary-, nephro-, and hepatotoxicities, presented in recent preclinical studies and case reports on the accidental or intentional ingestions with the most popular GBHs. Finally, they briefly describe modern and future healthcare methods and tools for GLP detection, determination, and detoxification. Future electronically powered, decision-making, and user-friendly devices targeting major GLP/GBH's modes of actions, i.e., dysbiosis and the inhibition of AChE, shall enable self-handled or point-of-care professional-assisted evaluation of the harm followed with rapid capturing GBH xenobiotics in the body and precise determining the GBH pathology-associated biomarkers levels.

Assessing the impact and mechanisms of environmental pollutants (heavy metals and pesticides) on the male reproductive system: a comprehensive review

The escalation of technological advancements, coupled with the increased use of hazardous chemicals, has emerged as a significant concern for human health. Exposure to environmental pollutants like heavy metals and pesticides (insecticides, herbicides and fungicides) is known to significantly contribute to various health problems, particularly affecting reproductive health. Disturbances in reproductive potential and reproductive toxicity in males are particularly worrisome. Existing literature suggests that exposure to these environmental pollutants significantly alters male reproductive parameters. Thus, it is imperative to thoroughly analyze, comprehend, and evaluate their impact on male reproductive toxicity. Oxidative stress and disruptions in redox equilibrium are major factors through which these pollutants induce changes in sperm parameters and affect the reproductive system. Insecticides, fungicides, and herbicides act as endocrine disruptors, interfering with the secretion and function of reproductive hormones such as testosterone and luteinizing hormone (LH), consequently impacting spermatogenesis. Additionally, heavy metals are reported to bio-accumulate in reproductive organs, acting as endocrine disruptors and triggering oxidative stress. The co-operative association of these pollutants can lead to severe damage. In this comprehensive review, we have conducted an in-depth analysis of the impact of these environmental pollutants on the male reproductive system, shedding light on the underlying mechanisms of action.

Analysis of Prussian carp (Carassius gibelio B.) oocytes under the influence of Roundup® herbicide

The aim of this study was to investigate the effect of Roundup® herbicide on the maturation of Prussian carp oocytes under laboratory conditions. The Prussian carp is currently one of the most common fish species in Polish freshwater ichthyofauna. For the investigation, oocytes from five sexually mature female Prussian carp were used, segmented into three groups, and incubated for 24 h in Cortland's saline, treated with varied concentrations of the herbicide Roundup® (0 ng - control, R1 - 10 ng/ml, and R2 - 100 ng/ml). Subsequent to this period, assays were performed using the prepared plates to determine the level of 17α,20β-dihydroxyprogesterone (17α,20β-P) utilizing the standard ELISA technique. In determining the 17α,20β-P via ELISA, the medium was extracted from each tested oocyte group. Oocyte maturity was assessed through preservation in serra fluid, and, to categorize the maturity stage of the oocytes utilizing a four-point scale - contingent upon the nucleus's position - the formerly preserved oocytes were dehydrated and subsequently analyzed. A contrast was noted in the percentage of oocytes at varied stages between the control group and the experimental groups. Specifically, a higher concentration of Roundup® (100 ng/ml) accelerated to expedite the initial migration of the nucleus in oocytes. In conclusion, the obtained results show the adverse effect of Roundup® on hormonal regulation and maturation in Prussian carp oocytes.

Mitochondria Quality Control and Male Fertility

Mitochondria are pivotal to cellular homeostasis, performing vital functions such as bioenergetics, biosynthesis, and cell signalling. Proper maintenance of these processes is crucial to prevent disease development and ensure optimal cell function. Mitochondrial dynamics, including fission, fusion, biogenesis, mitophagy, and apoptosis, maintain mitochondrial quality control, which is essential for overall cell health. In male reproduction, mitochondria play a pivotal role in germ cell development and any defects in mitochondrial quality can have serious consequences on male fertility. Reactive oxygen species (ROS) also play a crucial role in sperm capacitation, but excessive ROS levels can trigger oxidative damage. Any imbalance between ROS and sperm quality control, caused by non-communicable diseases or environmental factors, can lead to an increase in oxidative stress, cell damage, and apoptosis, which in turn affect sperm concentration, quality, and motility. Therefore, assessing mitochondrial functionality and quality control is essential to gain valuable insights into male infertility. In sum, proper mitochondrial functionality is essential for overall health, and particularly important for male fertility. The assessment of mitochondrial functionality and quality control can provide crucial information for the study and management of male infertility and may lead to the development of new strategies for its management.

Differentiation Disorders of Chara vulgaris Spermatids following Treatment with Propyzamide

Microtubules are cytoskeletal cell elements that also build flagella and cilia. Moreover, these structures participate in spermatogenesis and form a microtubular manchette during spermiogenesis. The present study aims to assess the influence of propyzamide, a microtubule-disrupting agent, on alga Chara vulgaris spermatids during their differentiation by means of immunofluorescent and electron microscopy methods. Propyzamide blocks the functioning of the β-tubulin microtubule subunit, which results in the creation of a distorted shape of a sperm nucleus at some stages. Present ultrastructural studies confirm these changes. In nuclei, an altered chromatin arrangement and nuclear envelope fragmentation were observed in the research as a result of incorrect nucleus-cytoplasm transport behavior that disturbed the action of proteolytic enzymes and the chromatin remodeling process. In the cytoplasm, large autolytic vacuoles and the dilated endoplasmic reticulum (ER) system, as well as mitochondria, were revealed in the studies. In some spermatids, the arrangement of microtubules present in the manchette was disturbed and the structure was also fragmented. The observations made in the research at present show that, despite some differences in the manchette between Chara and mammals, and probably also in the alga under study, microtubules participate in the intramanchette transport (IMT) process, which is essential during spermatid differentiation. In the present study, the effect of propyzamide on Chara spermiogenesis is also presented for the first time; however, the role of microtubule-associated proteins in this process still needs to be elucidated in the literature.

Exposure to bisphenol A induces neurotoxicity associated with synaptic and cytoskeletal dysfunction in neuro-2a cells

Bisphenol A (BPA) has been reported to injure the developing and adult brain. However, the underlying mechanism still remains elusive. This study used neuro-2a cells as a cellular model to investigate the neurotoxic effects of BPA. Microtubule-associated protein 2 (MAP2) and tau protein maintain microtubule normal function and promote the normal development of the nervous system. Synaptophysin (SYP) and drebrin (Dbn) proteins are involved in regulating synaptic plasticity. Cells were exposed to the minimum essential medium (MEM), 0.01% (v/v) DMSO, and 150 μM BPA for 12, 24, or 36 h. Morphological analysis revealed that the cells in the BPA-treated groups shrank and collapsed compared with those in the control groups. CCK-8 and lactate dehydrogenase assay (LDH) assays showed that the mortality of neuro-2a cells increased as the BPA treatment time was prolonged. Ultrastructural analysis further revealed that cells demonstrated nucleolar swelling, dissolution of nuclear and mitochondrial membranes, and partial mitochondrial condensation following exposure to BPA. BPA also decreased the relative protein expression levels of MAP2, tau, and Dbn. Interestingly, the relative protein expression levels of SYP increased. These results indicated that BPA inhibited the proliferation and disrupted cytoskeleton and synaptic integrity of neuro-2a cells.

Contaminants of Emerging Concern (CECs) and Male Reproductive Health: Challenging the Future with a Double-Edged Sword

Approximately 9% of couples are infertile, with half of these cases relating to male factors. While many cases of male infertility are associated with genetic and lifestyle factors, approximately 30% of cases are still idiopathic. Contaminants of emerging concern (CECs) denote substances identified in the environment for the first time or detected at low concentrations during water quality analysis. Since CEC production and use have increased in recent decades, CECs are now ubiquitous in surface and groundwater. CECs are increasingly observed in human tissues, and parallel reports indicate that semen quality is continuously declining, supporting the notion that CECs may play a role in infertility. This narrative review focuses on several CECs (including pesticides and pharmaceuticals) detected in the nearshore marine environment of False Bay, Cape Town, South Africa, and deliberates their potential effects on male fertility and the offspring of exposed parents, as well as the use of spermatozoa in toxicological studies. Collective findings report that chronic in vivo exposure to pesticides, including atrazine, simazine, and chlorpyrifos, is likely to be detrimental to the reproduction of many organisms, as well as to sperm performance in vitro. Similarly, exposure to pharmaceuticals such as diclofenac and naproxen impairs sperm motility both in vivo and in vitro. These contaminants are also likely to play a key role in health and disease in offspring sired by parents exposed to CECs. On the other side of the double-edged sword, we propose that due to its sensitivity to environmental conditions, spermatozoa could be used as a bioindicator in eco- and repro-toxicology studies.

Biological effects of sub-lethal doses of glyphosate and AMPA on cardiac myoblasts

Introduction: Glyphosate is the active compound of different non-selective herbicides, being the most used agriculture pesticide worldwide. Glyphosate and AMPA (one of its main metabolites) are common pollutants of water, soil, and food sources such as crops. They can be detected in biological samples from both exposed workers and general population. Despite glyphosate acts as inhibitor of the shikimate pathway, present only in plants and some microorganisms, its safety in mammals is still debated. Acute glyphosate intoxications are correlated to cardiovascular/neuronal damages, but little is known about the effects of the chronic exposure. Methods: We evaluated the direct biological effects of different concentrations of pure glyphosate/AMPA on a rat-derived cell line of cardiomyoblasts (H9c2) in acute (1-2 h) or sub-chronic (24-48 h) settings. We analyzed cell viability/morphology, ROS production and mitochondrial dynamics. Results: Acute exposure to high doses (above 10 mM) of glyphosate and AMPA triggers immediate cytotoxic effects: reduction in cell viability, increased ROS production, morphological alterations and mitochondrial function. When exposed to lower glyphosate concentrations (1 μM-1 mM), H9c2 cells showed only a slight variation in cell viability and ROS production, while mitochondrial dynamic was unvaried. Moreover, the phenotype was completely restored after 48 h of treatment. Surprisingly, the sub-chronic (48 h) treatment with low concentrations (1 μM-1 mM) of AMPA led to a late cytotoxic response, reflected in a reduction in H9c2 viability. Conclusion: The comprehension of the extent of human exposure to these molecules remains pivotal to have a better critical view of the available data.

Molecular mechanisms regulating spermatogenesis in vertebrates: Environmental, metabolic, and epigenetic factor effects

The renewal of the natural resources is one of the most concerning aspects of modern farming. In animal production, there are many barriers breeders and researchers have to overcome to develop new practices to improve reproductive potential and hasten sexual maturation of the commercially viable species, while maintaining meat quality and sustainability. With the utilization of molecular biology techniques, there have been relevant advances in the knowledge of spermatogenesis, especially in mammals, resulting in new possibilities to control male fertility and the selection of desirable characteristics. Most of these discoveries have not been implemented in animal production. In this review, recent studies are highlighted on the molecular pathways involved in spermatogenesis in the context of animal production. There is also exploration of the interaction between environmental factors and spermatogenesis and how this knowledge may revolutionize animal production techniques. Furthermore, new insights are described about the inheritance of desired characteristics in mammals and there is a review of nefarious actions of pollutants, nutrition, and metabolism on reproductive potential in subsequent generations. Even though there are these advances in knowledge base, results from recent studies indicate there are previously unrecognized environmental effects on spermatogenesis. The molecular mechanisms underlying this interaction are not well understood. Research in spermatogenesis, therefore, remains pivotal as a pillar of animal production sustainability.

The adverse impact of herbicide Roundup Ultra Plus in human spermatozoa plasma membrane is caused by its surfactant

The scarce research about the worldwide used glyphosate-based herbicide Roundup is controversial in human reproduction, especially spermatozoa. This study investigates the in vitro effect in human spermatozoa of Roundup Ultra Plus (RUP), its active ingredient glyphosate and its non-active, surfactant. Human spermatozoa were incubated (1 h, 37 °C) in presence/absence of RUP 0.01%, glyphosate, or equivalent surfactant concentration. Motility and sperm parameters were analyzed by C.A.S.A and flow cytometry, respectively. RUP significantly increases sperm plasma membrane lipid disorganization in a concentration-dependent manner while it decreases plasma membrane integrity. RUP significantly increases the death spermatozoa population after A23187-induced acrosome reaction, without affecting sperm viability, mitochondrial membrane potential, ROS content, acrosome membrane damage, phosphatidylserine exposure, A23187-induced acrosome reaction or GSK3 phosphorylation. RUP also significantly decreases motile and the a + b sperm populations. Interestingly, all sperm effects caused by RUP 0.01% are mimicked by its surfactant POEA at equivalent concentration. However, glyphosate does not affect any sperm parameter, even using 10-times higher concentration than the RUP 0.01% equivalent. RUP disturbs lipid organization and integrity of human sperm plasma membrane and reduces motility, without affecting viability or functional parameters. Importantly, RUP adverse effects in human spermatozoa are caused by the surfactant and no by glyphosate.

The effects of low-toxic herbicide Roundup and glyphosate on mitochondria

The effects of pesticides on the health of non-target living organisms in agricultural areas are critically important aspects for their safe use. Their release into the environment is an inevitable aspect for predicting and evaluation of the risk of their application. Roundup, a glyphosate-based herbicide, has been designed as an effective pesticide against weeds and now is the most widely used agrochemicals around the world due to its highly specific action of the biosynthesis of certain amino acids in plants. Despite it is claimed to be low toxic for not-target organisms, due to its broad application Roundup and products of its degradation were detected in organisms of diverse animals and humans. In this review, we describe animal and human studies of general adverse effects of Roundup and its principal substance glyphosate with focus on endocrine disruption, oxidative stress and behavioral disorders. At mechanistic level, we focus on the potential toxicity of the herbicide Roundup and glyphosate as effectors of bioenergetic functions of mitochondria. Their effects on mitochondrial membrane potential and oxidative phosphorylation are among described to date critical components responsible for its toxicity. Finally, we discuss general molecular mechanisms potentially involved in the interaction between glyphosate and mitochondria which to some extent are associated with generation of reactive oxygen species.

Impact of glyphosate and its formulation Roundup® on stallion spermatozoa

The growing and widespread use of glyphosate-based herbicides (GBHs) has raised an intense public debate about the impact of environmental contamination on animal and human health, including male fertility. The aim of this study was to deepen the impact of glyphosate (Gly) and GBHs on mammalian sperm investigating the effect of in vitro exposure of stallion spermatozoa to Gly and to its commercial formulation Roundup® (R). Spermatozoa were incubated at 37 °C with different Gly or R concentrations (from 0.5 to 720 μg/mL Gly or R at the same Gly-equivalent concentrations). After 1 h of incubation motility, viability, acrosome integrity, mitochondrial activity and ROS production were assessed. Gly, at all the concentrations tested, did not induce any detrimental impact on the sperm quality parameters evaluated. Conversely, R starting from 360 μg/mL (Gly-equivalent dose) significantly (P < 0.05) decreased total and progressive motility, viability, acrosome integrity, mitochondrial activity and the percentage of live spermatozoa with intact mitochondria not producing ROS. Our results indicate that the commercial formulation R is more toxic than its active molecule Gly and that the negative impact on stallion sperm motility might be likely due to a detrimental effect mainly at membrane and mitochondrial level and, at least in part, to redox unbalance. Moreover, based on the data obtained, it can be hypothesized a species-specificity in sperm sensitivity to Gly and GBHs as horse spermatozoa were negatively influenced at higher concentrations of R compared to those reported in literature to be toxic for human and swine male germ cells.

Reproductive toxicity of roundup®-treated feed on broiler breeder roosters and the amelioration of these deleterious effects with inclusion of humic acids in feed

Glyphosate-based herbicides (GBHs) such as RoundUp® are a staple of modern crop production, and as a result, residues of their ingredients are typically found in animal feeds. GBH ingredients have repeatedly been shown to impact the male reproductive health of various animals, but at present, the impact of GBH exposures on reproductive health have not been investigated in broiler breeder roosters. This study sought to determine the effect of these exposures on roosters as well as the ability of humic acids (HA) to counteract the effect of GBH exposure. Through 18 weeks of treatment with Roundup®-added or HA-added feeds compared against a common broiler breeder mash, negative effects of Roundup® exposure were seen on testis morphology as well as sperm quality. Increased exposure to Roundup® ingredients resulted in increased vacuolation of seminiferous tubule epithelium. Exposure to Roundup® impacted assessments of sperm quality including sperm mobility, viability and count during the experimental trail. HA supplementation served as a promising adsorptive additive by improving both morphology and sperm quality during the trial. Roundup® exposure was shown to have a negative influence on broiler breeder rooster reproductive health while HA improved reproductive health. The use of HA as an absorbent additive in broiler breeder feeds shows promise in improving reproductive efficiency in broiler breeders.

Chronic Dietary Exposure of Roosters to a Glyphosate-Based Herbicide Increases Seminal Plasma Glyphosate and AMPA Concentrations, Alters Sperm Parameters, and Induces Metabolic Disorders in the Progeny

The effects of chronic dietary Roundup (RU) exposure on rooster sperm parameters, fertility, and offspring are unknown. We investigated the effects of chronic RU dietary exposure (46.8 mg kg⁻¹ day⁻¹ glyphosate) for 5 weeks in 32-week-old roosters (n = 5 RU-exposed and n = 5 control (CT)). Although the concentrations of glyphosate and its main metabolite AMPA (aminomethylphosphonic acid) increased in blood plasma and seminal fluid during exposure, no significant differences in testis weight and sperm concentrations were observed between RU and CT roosters. However, sperm motility was significantly reduced, associated with decreased calcium and ATP concentrations in RU spermatozoa. Plasma testosterone and oestradiol concentrations increased in RU roosters. These negative effects ceased 14 days after RU removal from the diet. Epigenetic analysis showed a global DNA hypomethylation in RU roosters. After artificial insemination of hens (n = 40) with sperm from CT or RU roosters, eggs were collected and artificially incubated. Embryo viability did not differ, but chicks from RU roosters (n = 118) had a higher food consumption, body weight and subcutaneous adipose tissue content. Chronic dietary RU exposure in roosters reduces sperm motility and increases plasma testosterone levels, growth performance, and fattening in offspring.

Pleiotropic Outcomes of Glyphosate Exposure: From Organ Damage to Effects on Inflammation, Cancer, Reproduction and Development

Glyphosate is widely used worldwide as a potent herbicide. Due to its ubiquitous use, it is detectable in air, water and foodstuffs and can accumulate in human biological fluids and tissues representing a severe human health risk. In plants, glyphosate acts as an inhibitor of the shikimate pathway, which is absent in vertebrates. Due to this, international scientific authorities have long-considered glyphosate as a compound that has no or weak toxicity in humans. However, increasing evidence has highlighted the toxicity of glyphosate and its formulations in animals and human cells and tissues. Thus, despite the extension of the authorization of the use of glyphosate in Europe until 2022, several countries have begun to take precautionary measures to reduce its diffusion. Glyphosate has been detected in urine, blood and maternal milk and has been found to induce the generation of reactive oxygen species (ROS) and several cytotoxic and genotoxic effects in vitro and in animal models directly or indirectly through its metabolite, aminomethylphosphonic acid (AMPA). This review aims to summarize the more relevant findings on the biological effects and underlying molecular mechanisms of glyphosate, with a particular focus on glyphosate's potential to induce inflammation, DNA damage and alterations in gene expression profiles as well as adverse effects on reproduction and development.

Insights into the Role of Telomeres in Human Embryological Parameters. Opinions Regarding IVF

Telomeres promote genome integrity by protecting chromosome ends from the activation of the DNA damage response and protecting chromosomes from the loss of coding sequences due to the end replication problem. Telomere length (TL) is progressively shortened as age progresses, thus resulting in cellular senescence. Therefore, TL is in strong adverse linear correlation with aging. Mounting evidence supports the notion that telomeres and male/female infertility are in a close relationship, posing the biology of telomeres as a hot topic in the era of human-assisted reproduction. Specifically, the length of sperm telomeres is gradually increasing as men get older, while the telomere length of the oocytes seems not to follow similar patterns with that of sperm. Nonetheless, the telomere length of the embryos during the cleavage stages seems to have a paternal origin, but the telomere length can be further extended by telomerase activity during the blastocyst stage. The latter has been proposed as a new molecular biomarker with strong predictive value regarding male infertility. As far as the role of telomeres in assisted reproduction, the data is limited but the length of telomeres in both gametes seems to be affected mainly by the cause of infertility rather than the assisted reproductive therapy (ART) procedure itself. The present review aims to shed more light into the role of telomeres in human embryological parameters, including gametes and embryos and also presents opinions regarding the association between telomeres and in vitro fertilization (IVF).

Review: Mechanisms of Glyphosate and Glyphosate-Based Herbicides Action in Female and Male Fertility in Humans and Animal Models

Glyphosate (G), also known as N-(phosphonomethyl)glycine is the declared active ingredient of glyphosate-based herbicides (GBHs) such as Roundup largely used in conventional agriculture. It is always used mixed with formulants. G acts in particular on the shikimate pathway, which exists in bacteria, for aromatic amino acids synthesis, but this pathway does not exist in vertebrates. In recent decades, researchers have shown by using various animal models that GBHs are endocrine disruptors that might alter reproductive functions. Our review describes the effects of exposure to G or GBHs on the hypothalamic-pituitary-gonadal (HPG) axis in males and females in terms of endocrine disruption, cell viability, and proliferation. Most of the main regulators of the reproductive axis (GPR54, GnRH, LH, FSH, estradiol, testosterone) are altered at all levels of the HPG axis (hypothalamus, pituitary, ovaries, testis, placenta, uterus) by exposure to GBHs which are considered more toxic than G alone due to the presence of formulants such as polyoxyethylene tallow amine (POEA)." In addition, we report intergenerational impacts of exposure to G or GBHs and, finally, we discuss different strategies to reduce the negative effects of GBHs on fertility.

Transmission electron microscopic analysis of glyphosate induced cytotoxicity and its attenuation by N-acetyl-L-cysteine in caprine testicular germ cells in vitro

The agricultural pesticide poisoning is currently the most thrust area of human health concern. Pesticide-induced cytotoxicity and the corresponding reproductive toxicity in today's scenario is not a concealed reality that has to be considered for the continuation of respective race. Here, the transmission electron microscopy (TEM) technique was employed to investigate the adverse impact of glyphosate (GLY) and its mitigation by N-acetyl-L-cysteine (NAC) in goat testicular germ cells under in vitro conditions. The ultrastructural observations of testicular tissue from GLY-treated groups at different concentrations (0.1 and 4 mg/ml) and exposure durations (8 and 12 h) revealed that this organophosphate herbicide induced different apoptotic characteristics in testicular germ cells in a time- and dose-dependent manner. However, NAC (10 mM), being a potent antioxidant, was found to mitigate GLY-induced cytotoxicity in testicular cells as evidenced by fewer apoptotic characteristics in GLY plus NAC-treated groups, suggesting its beneficial potential in alleviating the GLY-induced gonadotoxicity in males.Abbreviations: GLY (Glyphosate), NAC (N-acetyl-L-cysteine), TEM (Transmission electron microscopic), GE (genetic engineered), Organophosphate (OPs).

The Effect of Glyphosate on Human Sperm: In Vitro Approximation

Introduction Glyphosate is an herbicide used to eradicate illicit crops; however, its use is controversial due to different health problems associated with it. The present study aims to evaluate the effects of glyphosate on human sperm in vitro.

Methods Twenty-two semen samples from healthy normozoospermic men were included; 11 semen samples were incubated with Panzer (INVESA S.A., Antiquia, Colombia) and 11 with Roundup (Monsanto Company, MO, USA). The changes in motility and viability were observed. Functional seminal parameters were evaluated as well.

Results The samples exposed to glyphosate showed less motility and viability; a decrease in the potential of the mitochondrial membrane was observed, and an increase in the lipoperoxidation of the membrane was evidenced.

Conclusion Based on the present results, we concluded that glyphosate has cytotoxic potential for exposed people and may affect their fertility.

Glyphosate-based herbicides: Evidence of immune-endocrine alteration

Glyphosate (G) is the active ingredient of the most widely used herbicide products. It targets the enzyme 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), which lacks in humans, suggesting to confer a low mammalian toxicity to G-based herbicides (GBHs). Despite this, the use of G is currently under intense debate. Many studies indicating its hazard and toxicity on non-target organisms are emerging, and associations between GBHs and immune-endocrine disturbances have been described. This review aims to investigate, based on recent epidemiological studies and studies performed in vitro and in vivo in animals, the possible association between GBHs and immune-endocrine alterations. Published data suggest that GBHs have endocrine disrupting potentiality targeting sex and thyroid hormones, although its relevance for humans will require further investigations. Evidence of immunotoxicity are limited compared to those on endocrine effects, but overall highlight possible noxious effects, including lung inflammation and rhinitis. An attractive hypothesis could be the one that connects microbiota dysbiosis with possible immune-endocrine outcomes. Indeed, several intestinal microorganisms express the enzyme EPSPS and, studies are emerging that highlight a possible G-induced dysbiosis. Considering the wide use of GBHs in agriculture, further studies investigating their noxious effects at levels relevant for human exposure should be performed. A critical analysis of emerging evidence of G toxicity is required to better characterize its safety profile. In addition, attention should be paid to the differences between G alone and its formulations, which, containing substances able to increase G absorption, may present a different toxicity profile.

Effect of Copper Sulphate and Cadmium Chloride on Non-Human Primate Sperm Function In Vitro

In order to address the large percentage of unexplained male infertility in humans, more detailed investigations using sperm functional tests are needed to identify possible causes for compromised fertility. Since many environmental and lifestyle factors might be contributing to infertility, future studies aiming to elucidate the effect of such factors on male fertility will need the use of appropriate research models. The current study aimed to assess the effects of two heavy metals, namely copper sulphate, and cadmium chloride, on non-human primate (NHP) sperm function in order to establish the possibility of using these primate species as models for reproductive studies. Our combined results indicated that the functionality of NHP spermatozoa is inhibited by the two heavy metals investigated. After in vitro exposure, detrimental effects, and significant lowered values (p < 0.05) were obtained for sperm motility, viability and vitality, acrosome intactness, and hyperactivation. These metals, at the tested higher concentrations, therefore, have the ability to impair sperm quality thereby affecting sperm fertilizing capability in both humans and NHPs.

Impaired mammalian sperm function and lower phosphorylation signaling caused by the herbicide Roundup® Ultra Plus are due to its surfactant component

The use of worldwide glyphosate-based herbicide Roundup® is growing and to date its effects on mammalian spermatozoa are controversial. This study aims to investigate the functional impact of in vitro exposure of pig spermatozoa to low concentrations of Roundup® Ultra Plus (RUP), similar to those present as environment contaminants, to its active ingredient glyphosate, and to the non-active component, surfactant polyoxyethyleneamine (POEA). Pig spermatozoa were incubated in Tyrode's basal medium (TBM) or Tyrode's complete medium (TCM) (1 h at 38.5 °C) with several RUP dilutions or equivalent concentrations of glyphosate or POEA. RUP treatment causes a significant dilution-dependent decrease in sperm motility, a significant increase in plasma membrane disorganization and reduction in GSK3β phosphorylation (TBM) and in two PKA substrates (TBM and TCM), whereas does not affect sperm viability or mitochondrial membrane potential (MMP). Equivalent glyphosate concentrations do not affect any functional sperm parameters. However, POEA concentrations equivalent to RUP dilutions mimic all RUP sperm effects: decrease sperm motility in a concentration-dependent manner, increase sperm plasma membrane lipid disorder and significantly inhibit GSK3β phosphorylation (TBM) and two PKA substrates without affecting sperm viability or MMP. In summary, low concentrations RUP herbicide cause sperm motility impairment without affecting sperm viability. This adverse effect could be likely due to a detrimental effect in the plasma membrane lipid organization and to inhibition of phosphorylation of both, GSK3β and specific PKA substrates. Importantly, our results indicate that negative effects of low RUP concentrations in pig spermatozoa function are likely caused by the surfactant included in its formulation and no by its active ingredient glyphosate.

Epigenetic Changes Associated With Exposure to Glyphosate-Based Herbicides in Mammals

Glyphosate is a phosphonomethyl amino acid derivative present in a number of non-selective and systemic herbicides. During the last years the use of glyphosate-based herbicide (GBH) has been increasing exponentially around the world, including Argentina. This fact added to the detection of glyphosate, and its main metabolite, amino methylphosphonic acid (AMPA), in environmental matrices such as soil, sediments, and food, has generated great concern about its risks for humans, animals, and environment. During the last years, there were controversy and intense debate regarding the toxicological effects of these compounds associated with the endocrine system, cancer, reproduction, and development. The mechanisms of action of GBH and their metabolites are still under investigation, although recent findings have shown that they could comprise epigenetic modifications. These are reversible mechanisms linked to tissue-specific silencing of gene expression, genomic imprinting, and tumor growth. Particularly, glyphosate, GBH, and AMPA have been reported to produce changes in global DNA methylation, methylation of specific genes, histone modification, and differential expression of non-coding RNAs in human cells and rodents. Importantly, the epigenome could be heritable and could lead to disease long after the exposure has ended. This mini-review summarizes the epigenetic changes produced by glyphosate, GBHs, and AMPA in humans and rodents and proposes it as a potential mechanism of action through which these chemical compounds could alter body functions.

Antioxidant-Based Therapies in Male Infertility: Do We Have Sufficient Evidence Supporting Their Effectiveness?

Under physiological conditions, reactive oxygen species (ROS) play pivotal roles in various processes of human spermatozoa. Indeed, semen requires the intervention of ROS to accomplish different stages of its maturation. However, ROS overproduction is a well-documented phenomenon occurring in the semen of infertile males, potentially causing permanent oxidative damages to a vast number of biological molecules (proteins, nucleic acids, polyunsaturated fatty acids of biological membrane lipids), negatively affecting the functionality and vitality of spermatozoa. ROS overproduction may concomitantly occur to the excess generation of reactive nitrogen species (RNS), leading to oxidative/nitrosative stress and frequently encountered in various human pathologies. Under different conditions of male infertility, very frequently accompanied by morpho-functional anomalies in the sperm analysis, several studies have provided evidence for clear biochemical signs of damages to biomolecules caused by oxidative/nitrosative stress. In the last decades, various studies aimed to verify whether antioxidant-based therapies may be beneficial to treat male infertility have been carried out. This review analyzed the results of the studies published during the last ten years on the administration of low-molecular-weight antioxidants to treat male infertility in order to establish whether there is a sufficient number of data to justify antioxidant administration to infertile males. An analysis of the literature showed that only 30 clinical studies tested the effects of the administration of low-molecular-weight antioxidants (administered as a single antioxidant or as a combination of different antioxidants with the addition of vitamins and/or micronutrients) to infertile males. Of these studies, only 33.3% included pregnancy and/or live birth rates as an outcome measure to determine the effects of the therapy. Of these studies, only 4 were case–control studies, and only 2 of them found improvement of the pregnancy rate in the group of antioxidant-treated patients. Additionally, of the 30 studies considered in this review, only 43.3% were case–control studies, 66.7% enrolled a number of patients higher than 40, and 40% carried out the administration of a single antioxidant. Therefore, it appears that further studies are needed to clearly define the usefulness of antioxidant-based therapies to treat male infertility.

Herbicides glyphosate and glufosinate ammonium negatively affect human sperm mitochondria respiration efficiency

The widespread cultivation of genetically modified organisms (GMOs) led to a widespread use of selective herbicides to which GMOs are resistant, thus increasing the concern about human exposure to them. Glyphosate (GLY) and glufosinate ammonium (GA), the active principles of the main formulations, have been investigated for their effects on human health, mainly cancer and reproductive toxicity. However, little is known about their effects on the molecular mechanisms related to sperm quality. To investigate the effects of GLY and GA on mitochondrial respiration efficiency, we took advantage of our already established ex vivo human sperm mitochondria assay. Since spermatozoa are highly regulated by sex steroids, we tested at first testosterone (T), di-hydroxytestosterone (DHT), 17β-estradiol (E2) and progesterone (P4). Then, we tested the effects of GLY and GA and of the hormone-like flavonoid quercetin (QRC) in a dose-dependent manner. The 0.1-1000 nM concentration range has been considered because it covers both the sexual hormones physiologically relevant concentrations (10 nM), triggering endogenously hormone-dependent signaling pathways, and the estimated (nM range) QRC dietary intake. Subsequently, co-incubation experiments were carried out with the two herbicides in the presence of 10 nM of each sex steroid and QRC. We found that: i) DHT and QRC are able to significantly reduce mitochondrial functionality at concentrations ≥ 10 nM; ii) GLY and GA negatively affect mitochondrial respiration efficiency; iii) in the presence of 10 nM DHT, the negative effect of GLY was increased; iiii) DHT, QRC and GA target mitochondria by using a mechanism different from GLY.

Glyphosate-based herbicide formulations and reproductive toxicity in animals

The adoption of genetically engineered (GE) crops in agriculture has increased dramatically over the last few decades. Among the transgenic plants, those tolerant to the herbicide glyphosate are among the most common. Weed resistance to glyphosate-based herbicides (GBHs) has been on the rise, leading to increased herbicide applications. This, in turn, has led to increased glyphosate residues in feed. Although glyphosate has been considered to be generally safe to animal health, recent studies have shown that GBHs have potential to cause adverse effects in animal reproduction, including disruption of key regulatory enzymes in androgen synthesis, alteration of serum levels of estrogen and testosterone, damage to reproductive tissues and impairment of gametogenesis. This review emphasizes known effects of GBHs on reproductive health as well as the potential risk GBH residues pose to animal agriculture.

Ovarian mitochondrial and oxidative stress proteins are altered by glyphosate exposure in mice

Glyphosate (GLY) usage for weed control is extensive. To investigate ovarian impacts of chronic GLY exposure, female C57BL6 mice were orally administered saline as vehicle control (CT) or GLY at 0.25 (G0.25), 0.5 (G0.5), 1.0 (G1.0), 1.5 (G1.5), or 2 (G2.0) mg/kg for five days per wk. for 20 wks. Feed intake increased (P < .05) in G1.5 and G2.0 mice and body weight increased (P < .05) in G1.0 mice. There was no impact of GLY on estrous cyclicity, nor did GLY affect circulating levels of 17β-estradiol or progesterone. Exposure to GLY did not impact heart, liver, spleen, kidney or uterus weight. Both ovarian weight and follicle number were increased (P < .05) by G2.0 but not affected at lower GLY concentrations. There were no detectable effects of GLY on ovarian protein abundance of pAKT, AKT, pAKT:AKT, γH2AX, STAR, CYP11A1, HSD3B, CYP19A, ERA or ERB. Increased (P < .05) abundance of ATM protein was observed at G0.25 but not higher GLY doses. A dose-dependent effect (P < .10) of GLY exposure on ovarian protein abundance as quantified by LC-MS/MS was observed (G0.25-4 increased, 19 decreased; G0.5-5 increased, 25 decreased; G1.0-65 increased, 7 decreased; G1.5-145 increased, 2 decreased; G2.0-159 increased, 4 decreased). Pathway analysis was performed using DAVID and identified glutathione metabolism, metabolic and proteasome pathways as GLY exposure targets. These data indicate that chronic low-level exposure to GLY alters the ovarian proteome and may ultimately impact ovarian function.

Nigral and ventral tegmental area lesioning induces testicular and sperm morphological abnormalities in a rotenone model of Parkinson's disease

Although sexual health is affected by Parkinson's disease (PD), the effect on testicular health and/or sperm quality is not well discussed. After 21 days of rotenone lesioning, we observed dopaminergic neuronal degeneration in the substantia nigra and hypothalamus. There were minimal SPACA-1-expressing epididymal spermatozoa with morphological abnormalities, scanty luminal spermatozoa and reduced testicular spermatids and post-meiotic germ cells indicating hypospermatogenesis. Occludin-expressing sertoli cells were dispersed over a wide area indicating compromised blood-testes barrier. Activated caspase-3 expression was intense while immunoreactivity of spermatogenic-enhancing SRY and GADD45 g was weak. Although serum follicle stimulating hormone level was not affected, the lesion was associated with reduced serum testosterone level, testicular oxidative damage and inhibition of acetylcholinesterase activity, even when rotenone was not detected in the testes. Together, dopaminergic lesions may mediate testicular and sperm abnormalities via the brain-hypothalamic-testicular circuit independent of the pituitary, thereby establishing a causal link between Parkinsonism and reproductive dysfunction.

Effects of Roundup and its main component, glyphosate, upon mammalian sperm function and survival

The wide use of glyphosate-based herbicides (GBHs) has become a matter of concern due to its potential harmful effects on human health, including men fertility. This study sought to investigate, using the pig as a model, the impact of pure glyphosate and its most known commercial formulation, Roundup, on sperm function and survival. With this purpose, fresh commercial semen doses were incubated with different concentrations (0-360 µg/mL) of glyphosate (GLY; exp. 1) or Roundup, at the equivalent GLY concentration (exp. 2), at 38 °C for 3 h. Glyphosate at 360 µg/mL significantly (P < 0.05) decreased sperm motility, viability, mitochondrial activity and acrosome integrity but had no detrimental effect at lower doses. On the other hand, Roundup did significantly (P < 0.05) reduce sperm motility at ≥ 5 µg/mL GLY-equivalent concentration; mitochondrial activity at ≥ 25 µg/mL GLY-equivalent concentration; and sperm viability and acrosome integrity at ≥ 100 µg/mL GLY-equivalent concentration as early as 1 h of incubation. In a similar fashion, GLY and Roundup did not inflict any detrimental effect on sperm DNA integrity. Taken together, these data indicate that, while both glyphosate and Roundup exert a negative impact on male gametes, Roundup is more toxic than its main component, glyphosate.

Bisphenol A Analogues in Food and Their Hormonal and Obesogenic Effects: A Review

Bisphenol A (BPA) is the most well-known compound from the bisphenol family. As BPA has recently come under pressure, it is being replaced by compounds very similar in structure, but data on the occurrence of these BPA analogues in food and human matrices are limited. The main objective of this work was to investigate human exposure to BPA and analogues and the associated health effects. We performed a literature review of the available research made in humans, in in vivo and in vitro tests. The findings support the idea that exposure to BPA analogues may have an impact on human health, especially in terms of obesity and other adverse health effects in children.

Effect of the herbicide atrazine and its major metabolite, DACT, on bovine sperm cryotolerance

During freezing and thawing procedures, sperm are exposed to chemical and/or physical stressors that may cause adverse and harmful changes to sperm membranes. Accurate evaluation of the structural and functional integrity of fresh as well as cryopreserved sperm is highly important in predicting sperm fertilization capacity and success of artificial insemination (AI). The herbicide atrazine (ATZ) and its major metabolite, diaminochlorotriazine (DACT) are considered a ubiquitous environmental contaminants and endocrine disruptors, which deleteriously effect sperm function. Taking into consideration possible damage caused by environmental contaminants to sperm membranes, additive effects during cryopreservation cannot be ruled out. The aim of the current study was to evaluate the effect of ATZ (0.1 or 1 μM) and DACT (1 or 10 μM) exposure during or after cryopreservation on bovine sperm cryotolerance. Sperm membrane integrity and functionality were evaluated using fluorimetric probes: (1) double-stranded DNA was examined by 4',6-diamidino-2-phenylindole; (2) plasma membrane integrity was examined by propidium iodide; (3) acrosome reaction (AR) was examined by fluorescein isothiocyanate-conjugated Pisum sativum agglutinin; mitochondrial membrane potential (ΔΨm) was examined by 5,5',6,6'-tetra-chloro-1,1',3,3'-tetraethylbenzimidazolyl carbocyanine iodide fluorescent probe. The findings demonstrate, that exposure of sperm to ATZ (0.1 or 1 μM) or DACT (1 or 10 μM) during cryopreservation increased the proportion of dead sperm relative to the control (P < 0.09); exposure to DACT (1 or 10 μM) increased ΔΨm (P < 0.03). Neither ATZ nor DACT affected spontaneous AR. In contrast, the proportion of sperm with Ca⁺⁺ ionophore-induced AR was lower after exposure to 1 μM DACT (P < 0.05). Following freezing and thawing procedures, exposing sperm to 1 μM ATZ increased the proportion of dead sperm relative to the control (P < 0.05), but had no significant effect on sperm ΔΨm or AR. In conclusion, exposing sperm to endocrine-disrupting chemicals such as ATZ or DACT during cryopreservation reduces sperm cryotolerance and resistance post-thawing.

Roundup®, but Not Roundup-Ready® Corn, Increases Mortality of Drosophila melanogaster

Genetically modified foods have become pervasive in diets of people living in the US. By far the most common genetically modified foods either tolerate herbicide application (HT) or produce endogenous insecticide (Bt). To determine whether these toxicological effects result from genetic modification per se, or from the increase in herbicide or insecticide residues present on the food, we exposed fruit flies, Drosophila melanogaster, to food containing HT corn that had been sprayed with the glyphosate-based herbicide Roundup®, HT corn that had not been sprayed with Roundup®, or Roundup® in a variety of known glyphosate concentrations and formulations. While neither lifespan nor reproductive behaviors were affected by HT corn, addition of Roundup® increased mortality with an LC50 of 7.1 g/L for males and 11.4 g/L for females after 2 days of exposure. Given the many genetic tools available, Drosophila are an excellent model system for future studies about genetic and biochemical mechanisms of glyphosate toxicity.

31P NMR Investigations on Roundup Degradation by AOP Procedures

The reactions of (N-(PhosphonoMethyl)Glycine) PMG with H2O2 in homogenous systems were investigated using 31P NMR (Nuclear Magnetic Resonance). These reactions were carried out in two reaction modes: without UV radiation and under UV radiation. The reactions of PMG with H2O2 without UV radiation were carried out in two modes: the degradations of PMG (0.1 mmol) by means of 5–10 molar excess of hydrogen dioxide (PMG-H2O2 = 1:5 and 1:10) and the degradation of PMG (0.1 mmol) in homogenous Fenton reactions (PMG-H2O2-Fe2+ = 1:10:0.05 and 1:10:0.1). All reactions were carried out at ambient temperature, at pH 3.5, for 48 h. The reactions of PMG (in Roundup herbicide composition, 12 mmol) with H2O2 under UV radiation (254 nm) were carried out using 5 × molar excess of H2O2 (60 mmol), in the pH range of 2 ≤ pH ≤ 12, for 6 h. In this mode of PMG oxidation, the splitting of C-P was observed in the ratios dependent on the applied pH of the reaction mixture.

Automodified Poly(ADP-Ribose) Polymerase Analysisto Monitor DNA Damagein Peripheral Lymphocytes of Floriculturists Occupationally Exposed to Pesticides

Increased DNA damage and the propension to cancer development, depend on the modulation of the mechanisms to control and maintain genomic integrity. Poly(ADP-Ribose)Polymerase activation and automodification are early responses to genotoxic stress. Upon binding to DNA strand breaks, the enzyme, a molecular DNA nick sensor, is hyperactivated: this is the first step in a series of events leading to either DNA repair or apoptosis. Enzyme hyperactivation and automodification can be easily measured and are widely used to look at DNA damage extent in the cell. We investigated whether these two markers (increased catalytic activity and auto modification), could help to monitor DNA damage in lymphocytes of flower growers from Southern Italy, occupationally exposed to pesticides. Peripheral lymphocyte lysates were analyzed for Poly(ADP-Ribose)Polymerase activity, and by SDS-PAGE and anti-Poly(ADP-Ribose)Polymerase 1-antibodyto measure automodified Poly(ADP-Ribose)Polymerase levels bydensitometry. Poly(ADP-Ribose)Polymerase activity and PARP automodification followed the same trend. Growers daily exposed to pesticides, showed both biomarkers very high, either in the presence or in the absence of pathologies. PARP activity and auto-modification in peripheral blood lymphocytes are possible, non-invasive, androutinartools to monitor the healthy conditions of floricoltorists.

Calibration of sperm concentration for in vitro fertilization in a mouse reprotoxicity model

Xenobiotics, such as chemicals and pesticides, may result in adverse effects on reproduction in human and animals. Using in-vitro embryo production as a testing system reveals details of fertilization (IVF) and early embryonic development (IVC). The aim of our study was to perform a systematical calibration of sperm concentration in an IVF/IVC system, using an outbred mouse strain, and further determine the sperm concentration that furnishes a sensitive assessment of sperm fertilizing capacity in relation to reprotoxic evaluations. By performing breakpoint analysis, the results revealed a maximum two-cell percentage (51%, 95% CI: 38 to 69%) at 3.6 × 10⁴ sperm/ml (95% CI: 2.1 × 10⁴ to 6.1 × 10⁴). For future application of the IVF/IVC system, a sperm concentration lower than this breakpoint concentration is required to be within the responsive range for determining sperm fertilizing capacity. We conclude that a relatively low sperm concentration (2.5 × 10⁴ sperm/ml) is a precondition in a mouse IVF/IVC system in order to detect potential reprotoxic effects on sperm fertilizing capacity. Our study illustrates that a systematic approach is necessary for validation and appropriate use of such in-vitro system used for reproductive toxicity testing.

Decreased Capacity for Sperm Production Induced by Perinatal Bisphenol A Exposure Is Associated with an Increased Inflammatory Response in the Offspring of C57BL/6 Male Mice

Many previous studies have indicated the adverse effects of bisphenol A (BPA) on sperm production and quality; however, the mechanisms underlying BPA male reproductive toxicity have yet to be elucidated. The main purpose of this study was to investigate the effect of perinatal exposure to BPA on the spermatogenic capacity of male offspring, and to explore the possible influence of inflammatory responses in BPA reproductive toxicity. Twenty-one pregnant C57BL/6mice were randomly divided into three groups: a control group, a group receiving 0.2 μg/mL (LBPA), and a group receiving 2 μg/mL of BPA (HBPA), all via drinking water from gestational day 6 to the end of lactation. After weaning, one male mouse was randomly selected from each group (n = 7/group); these three mice were fed a normal diet and drinking water for 1 month. Levels of serum testosterone (T) and tumor necrosis factor (TNF)-α were then measured in all mice. Sperm count and the proportion of sperm malformation were also determined. The levels of Toll-like receptor 4 (TLR4), nuclear factor (NF)-κB, and aryl hydrocarbon receptor (AhR) protein expression in the testis tissue were determined. Analysis showed that the proportion of sperm malformation increased in the LBPA and HBPA groups (p < 0.05). Sperm count significantly decreased only in the HBPA group (p < 0.05), while the levels of serum TNF-α increased in the LBPA and HBPA groups (p < 0.05). Levels of serum T decreased significantly in the HBPA group, compared with controls (p < 0.05). Levels of TLR4 and NF-κB protein expression in the testis were significantly higher in the LBPA and HBPA groups (p < 0.05 or p < 0.01), while AhR protein expression was higher and seminiferous tubules in the testis showed more damage in the HBPA group compared to controls (p < 0.05 and p < 0.01, respectively). Our results showed that perinatal exposure to low or high doses of BPA decreased the capacity for spermatogenesis in male offspring, which may be associated with an inflammatory response activated by the TLR4/ NF-κB and AhR signaling pathways in the testis.

Research Trends and Hotspots Analysis Related to the Effects of Xenobiotics on Glucose Metabolism in Male Testes

This study aimed to integrate and analyze the existing studies and to explore research trends and hotspots related to the effects of xenobiotics on glucose metabolism in male testes. All articles were retrieved from the PubMed database, from an inception date up to 10 June 2017. CiteSpace software (version 5.1.R8 SE) was used for the co-word cluster analysis. A total of 165 eligible publications were included in this study. In 1949⁻1959, only two articles were published. After 1960, the number of articles increased steadily. These articles were published in 97 journals, in particular, in the Indian Journal of Experimental Biology (11 articles, 6.7%). Most of the authors (87.0%) only published one article. Only a few established research teams, mostly from the USA, worked consistently in this field. The main xenobiotics that had been studied were medicine and common environmental pollutants, e.g., gossypol, cadmium, di-n-butyl phthalate, and alpha-chlorohydrin. The hotspot keywords were Sertoli cell, lactate dehydrogenase, 6-phosphate dehydrogenase, oxidative stress, and glucose metabolism. The focus of research had been changed overtime. This is the first bibliometric study between xenobiotics and glucose metabolism in the male testes. The findings suggest that environmental pollutants have become a huge concern, and related research should be strengthened.

The Effect of Glyphosate on Human Sperm Motility and Sperm DNA Fragmentation

Glyphosate is the active ingredient of Roundup®, which is one of the most popular herbicides worldwide. Although many studies have focused on the reproductive toxicity of glyphosate or glyphosate-based herbicides, the majority of them have concluded that the effect of the specific herbicide is negligible, while only a few studies indicate the male reproductive toxicity of glyphosate alone. The aim of the present study was to investigate the effect of 0.36 mg/L glyphosate on sperm motility and sperm DNA fragmentation (SDF). Thirty healthy men volunteered to undergo semen analysis for the purpose of the study. Sperm motility was calculated according to WHO 2010 guidelines at collection time (zero time) and 1 h post-treatment with glyphosate. Sperm DNA fragmentation was evaluated with Halosperm® G2 kit for both the control and glyphosate-treated sperm samples. Sperm progressive motility of glyphosate-treated samples was significantly reduced after 1 h post-treatment in comparison to the respective controls, in contrast to the SDF of glyphosate-treated samples, which was comparable to the respective controls. Conclusively, under these in vitro conditions, at high concentrations that greatly exceed environmental exposures, glyphosate exerts toxic effects on sperm progressive motility but not on sperm DNA integrity, meaning that the toxic effect is limited only to motility, at least in the first hour.