Effects of oral exposure to silver nanoparticles on the sperm of rats

A Review of in vivo Toxicity of Quantum Dots in Animal Models

Tremendous research efforts have been devoted to nanoparticles for applications in optoelectronics and biomedicine. Over the past decade, quantum dots (QDs) have become one of the fastest growing areas of research in nanotechnology because of outstanding photophysical properties, including narrow and symmetrical emission spectrum, broad fluorescence excitation spectrum, the tenability of the emission wavelength with the particle size and composition, anti-photobleaching ability and stable fluorescence. These characteristics are suitable for optical imaging, drug delivery and other biomedical applications. Research on QDs toxicology has demonstrated QDs affect or damage the biological system to some extent, and this situation is generally caused by the metal ions and some special properties in QDs, which hinders the further application of QDs in the biomedical field. The toxicological mechanism mainly stems from the release of heavy metal ions and generation of reactive oxygen species (ROS). At the same time, the contact reaction with QDs also cause disorders in organelles and changes in gene expression profiles. In this review, we try to present an overview of the toxicity and related toxicity mechanisms of QDs in different target organs. It is believed that the evaluation of toxicity and the synthesis of environmentally friendly QDs are the primary issues to be addressed for future widespread applications. However, considering the many different types and potential modifications, this review on the potential toxicity of QDs is still not clearly elucidated, and further research is needed on this meaningful topic.

Putative adverse outcome pathways for silver nanoparticle toxicity on mammalian male reproductive system: a literature review

BACKGROUND

Adverse outcome pathways (AOPs) are conceptual frameworks that organize knowledge about biological interactions and toxicity mechanisms. They present a sequence of events commencing with initial interaction(s) of a stressor, which defines the perturbation in a biological system (molecular initiating event, MIE), and a dependent series of key events (KEs), ending with an adverse outcome (AO). AOPs have recently become the subject of intense studies in a view to better understand the mechanisms of nanomaterial (NM) toxicity. Silver nanoparticles (Ag NPs) are one of the most explored nanostructures and are extensively used in various application. This, in turn, has increased the potential for interactions of Ag NPs with environments, and toxicity to human health. The aim of this study was to construct a putative AOPs (pAOP) related to reproductive toxicity of Ag NPs, in order to lay the groundwork for a better comprehension of mechanisms affecting both undesired toxicity (against human cell) and expected toxicity (against microorganisms).

METHODS

PubMed and Scopus were systematically searched for peer-reviewed studies examining reproductive toxicity potential of Ag NPs. The quality of selected studies was assessed through ToxRTool. Eventually, forty-eight studies published between 2005 and 2022 were selected to identify the mechanisms of Ag NPs impact on reproductive function in human male. The biological endpoints, measurements, and results were extracted from these studies. Where possible, endpoints were assigned to a potential KE and an AO using expert judgment. Then, KEs were classified at each major level of biological organization.

RESULTS

We identified the impairment of intracellular SH-containing biomolecules, which are major cellular antioxidants, as a putative MIE, with subsequent KEs defined as ROS accumulation, mitochondrial damage, DNA damage and lipid peroxidation, apoptosis, reduced production of reproductive hormones and reduced quality of sperm. These successive KEs may result in impaired male fertility (AO).

CONCLUSION

This research recapitulates and schematically represents complex literature data gathered from different biological levels and propose a pAOP related to the reproductive toxicity induced by AgNPs. The development of AOPs specific to NMs should be encouraged in order to provide new insights to gain a better understanding of NP toxicity.

Inactivation of mammalian spermatozoa on the exposure of TiO2 nanorods deposited with noble metals

Titanium dioxide (TiO₂) nanorods (NRs) are well-known semiconducting and catalytic material that has been widely applied, but their toxicities have also attracted recent interest. In this study, we investigated and compared the toxic effects of TiO₂ NRs and TiO₂ NRs loaded with Ag or Au NPs on boar spermatozoa. As a result, sperm incubated with Ag-TiO₂ NRs showed lower motility than sperm incubated with controls (with or without TiO₂ NRs) or Au-TiO₂ NRs. In addition, sperm viability and acrosomal integrity were defective in the presence of Ag-TiO₂ NRs, and the generation of intracellular reactive oxygen species (ROS) increased significantly when spermatozoa were incubated with 20 μg/ml Ag-TiO₂ NRs. We discussed in depth the charge transfer mechanism between enzymatic NADPH and Ag-TiO₂ NRs in the context of ROS generation in spermatozoa. The effects we observed reflected the fertilization competence of sperm incubated with Ag-TiO₂ NRs; specifically sperm penetration and embryonic development rates by in vitro fertilization were reduced by Ag-TiO₂ NRs. To summarize, our findings indicate that exposure to Ag-TiO₂ NRs could affect male fertilization fecundity and caution that care be exercised when using these NRs.

Impact of Nanoparticles on Male Fertility: What Do We Really Know? A Systematic Review

The real impact of nanoparticles on male fertility is evaluated after a careful analysis of the available literature. The first part reviews animal models to understand the testicular biodistribution and biopersistence of nanoparticles, while the second part evaluates their in vitro and in vivo biotoxicity. Our main findings suggest that nanoparticles are generally able to reach the testicle in small quantities where they persist for several months, regardless of the route of exposure. However, there is not enough evidence that they can cross the blood-testis barrier. Of note, the majority of nanoparticles have low direct toxicity to the testis, but there are indications that some might act as endocrine disruptors. Overall, the impact on spermatogenesis in adults is generally weak and reversible, but exceptions exist and merit increased attention. Finally, we comment on several methodological or analytical biases which have led some studies to exaggerate the reprotoxicity of nanoparticles. In the future, rigorous clinical studies in tandem with mechanistic studies are needed to elucidate the real risk posed by nanoparticles on male fertility.

Beneficial effects of Spirulina platensis on mice testis damaged by silver nanoparticles

Silver nanoparticles (AgNPs) have been used widely in medical applications and various industries. Humans could be exposed to the risk of AgNPs toxicity through different routes. The current study aimed to investigate the role of Spirulina platensis (SP) against the side effects of AgNPs on mice testis. Adult male NMRI mice were divided into four groups: control group, SP group (300 mg/kg bwt), AgNPs (20 nm) group (500 mg/kg bwt), Co-treated group (SP + AgNPs). The groups were treated orally for 35 days. Subsequently, epididymal sperm parameters, sperm DNA integrity, daily sperm production (DSP), sexual hormones level, malondialdehyde (MDA), total antioxidant capacity (TAC) and spermatogenesis indices were measured. In addition, the histopathology of testes was evaluated using tissue processing, haematoxylin-eosin staining and stereology techniques. A significant decrease in the number of spermatogenic cells, Leydig cells and sperm parameters was observed in the AgNPs treated group. Serum levels of testosterone and TAC were decreased significantly following AgNPs treatment. Also, MDA incremented in the serum of AgNPs treated mice. The stereological analysis revealed that AgNPs exposure induced histopathological changes in the seminiferous tubules, degeneration and dissociation of spermatogenic cells. In contrast, SP co-administration significantly counteracted AgNPs reproductive toxicity impacts. SP co-exposure caused an increase in spermatogenesis indices, TAC and also a decrease in MDA. SP improved the histopathological changes of testes tissue and spermatozoa abnormalities. In parallel, SP modulated levels of testosterone, FSH and LH. Spirulina platensis exhibited the protective potential by regulating oxidative stress against AgNPs-induced reproductive toxicity. SP could be a candidate therapy against AgNPs reprotoxic impacts.

An Overview of Essential Microelements and Common Metallic Nanoparticles and Their Effects on Male Fertility

Numerous factors affect reproduction, including stress, diet, obesity, the use of stimulants, or exposure to toxins, along with heavy elements (lead, silver, cadmium, uranium, vanadium, mercury, arsenic). Metals, like other xenotoxins, can cause infertility through, e.g., impairment of endocrine function and gametogenesis or excess production of reactive oxygen species (ROS). The advancement of nanotechnology has created another hazard to human safety through exposure to metals in the form of nanomaterials (NMs). Nanoparticles (NPs) exhibit a specific ability to penetrate cell membranes and biological barriers in the human body. These ultra-fine particles (<100 nm) can enter the human body through the respiratory tract, food, skin, injection, or implantation. Once absorbed, NPs are transported to various organs through the blood or lymph. Absorbed NPs, thanks to ultrahigh reactivity compared to bulk materials in microscale size, disrupt the homeostasis of the body as a result of interaction with biological molecules such as DNA, lipids, and proteins; interfering with the functioning of cells, organs, and physiological systems; and leading to severe pathological dysfunctions. Over the past decades, much research has been performed on the reproductive effects of essential trace elements. The research hypothesis that disturbances in the metabolism of trace elements are one of the many causes of infertility has been unquestionably confirmed. This review examines the complex reproductive risks for men regarding the exposure to potentially harmless xenobiotics based on a series of 298 articles over the past 30 years. The research was conducted using PubMed, Web of Science, and Scopus databases searching for papers devoted to in vivo and in vitro studies related to the influence of essential elements (iron, selenium, manganese, cobalt, zinc, copper, and molybdenum) and widely used metallic NPs on male reproduction potential.

Safety and Toxicity Implications of Multifunctional Drug Delivery Nanocarriers on Reproductive Systems In Vitro and In Vivo

In the recent past, nanotechnological advancements in engineered nanomaterials have demonstrated diverse and versatile applications in different arenas, including bio-imaging, drug delivery, bio-sensing, detection and analysis of biological macromolecules, bio-catalysis, nanomedicine, and other biomedical applications. However, public interests and concerns in the context of human exposure to these nanomaterials and their consequential well-being may hamper the wider applicability of these nanomaterial-based platforms. Furthermore, human exposure to these nanosized and engineered particulate materials has also increased drastically in the last 2 decades due to enormous research and development and anthropocentric applications of nanoparticles. Their widespread use in nanomaterial-based industries, viz., nanomedicine, cosmetics, and consumer goods has also raised questions regarding the potential of nanotoxicity in general and reproductive nanotoxicology in particular. In this review, we have summarized diverse aspects of nanoparticle safety and their toxicological outcomes on reproduction and developmental systems. Various research databases, including PubMed and Google Scholar, were searched for the last 20 years up to the date of inception, and nano toxicological aspects of these materials on male and female reproductive systems have been described in detail. Furthermore, a discussion has also been dedicated to the placental interaction of these nanoparticles and how these can cross the blood–placental barrier and precipitate nanotoxicity in the developing offspring. Fetal abnormalities as a consequence of the administration of nanoparticles and pathophysiological deviations and aberrations in the developing fetus have also been touched upon. A section has also been dedicated to the regulatory requirements and guidelines for the testing of nanoparticles for their safety and toxicity in reproductive systems. It is anticipated that this review will incite a considerable interest in the research community functioning in the domains of pharmaceutical formulations and development in nanomedicine-based designing of therapeutic paradigms.

Reproductive toxicity investigation of silica nanoparticles in male pubertal mice

Silica nanoparticles (SiNPs), one of the most produced nanoparticles (NPs) in the world, are used in all aspects of life. The increased application of SiNPs, especially in medicine, has raised considerable concern regarding their toxicological impact. Previous studies have shown that SiNPs can pass through the reproductive barrier and cause reproductive organ dysfunction by destroying Sertoli cells, Leydig cells, and germ cells. However, little is known about the mechanism of SiNPs-induced reproductive toxicity. In the present study, 5-week-old male mice were intraperitoneally administered SiNPs per day for 1 week at a dose of 0.2 mg per mouse. The results showed that SiNPs could cause damage to the structure of the testis and the epididymis and change the reproductive organ coefficients, leading to decreases of 56.1% and 55.3% in the rates of sperm concentration and motility and an increase of 168.8% in the rate of sperm abnormality. Moreover, the serum testosterone level obviously decreased from 18.77 to 5.23 µg/ml after exposure, and the transcription statuses of some key genes involved in the synthesis and transport of testosterone in the testis were also affected. Additional experiments showed that SiNPs exposure during puberty induced oxidative stress and an inflammatory response, as shown by the changed activity of superoxide dismutase (SOD), increased contents of malondialdehyde (MDA), and excess expression of proinflammatory factors, including TNF-α and IL-1β. Furthermore, the administration of SiNPs caused DNA damage and cell apoptosis, which were presented by the increased apoptotic cells in the sections of testis and epididymis and activation of the TNF-α/TNFR I-mediated pro-apoptotic pathway. In conclusion, these results indicate that SiNPs exposure during puberty significantly damaged the structure and function of the testis and epididymis by inducing oxidative stress and cell apoptosis. This study provides novel insight into SiNPs-induced reproductive toxicity during puberty, which warrants a more careful assessment of SiNPs before their application in juvenile supplies.

Time-delayed effects of a single application of AgNPs on structure of testes and functions in Blaps polychresta Forskal, 1775 (Coleoptera: Tenebrionidae)

Silver nanoparticles (AgNPs) are currently the most frequently used engineered nanoparticles. The penetration of AgNPs into ecosystems is undeniable, and their adverse effects on organism reproduction are of fundamental importance for ecosystem stability. In this study, the survival time of the Egyptian beetle Blaps polychresta Forskal, 1775 (Coleoptera: Tenebrionidae), after a single application of 7 different doses, was calculated for 30 days. Then, for the group for which the effect on mortality was calculated as LOAEL - the Lowest Observed Adverse Effect Level, namely, 0.03 mg AgNPs/g body weight (b.w.t.), the following were assessed: structure and ultrastructure of gonads by TEM and SEM, cell viability by cytometry, DNA damage by the comet assay, and a variety of stress markers by spectrophotometric methods. A dose-dependent reduction in the survival time of the insects was revealed. Detailed analysis of the testes of beetles treated with 0.03 mg AgNPs/g b.w.t. revealed numerous adverse effects of nanoparticles in structure and ultrastructure, accompanied by increased apoptosis (but not necrosis), increased DNA damage, increased lipid peroxidation, and decreased levels of antioxidant enzymes. Most likely, the observed results are connected with the gradual release of Ag⁺ from the surface of the nanoparticles, which, once applied, are internalized in cells and become a long-lasting, stable source of Ag⁺ ions. Thus, a single exposure to AgNPs may have the effects of chronic exposure and lead to structural damage and dysfunction of the gonads of B. polychresta.

Switching to nanonutrients for sustaining agroecosystems and environment: the challenges and benefits in moving up from ionic to particle feeding

The worldwide agricultural enterprise is facing immense pressure to intensify to feed the world's increasing population while the resources are dwindling. Fertilizers which are deemed as indispensable inputs for food, fodder, and fuel production now also represent the dark side of the intensive food production system. With most crop production systems focused on increasing the quantity of produce, indiscriminate use of fertilizers has created havoc for the environment and damaged the fiber of the biogeosphere. Deteriorated nutritional quality of food and contribution to impaired ecosystem services are the major limiting factors in the further growth of the fertilizer sector. Nanotechnology in agriculture has come up as a better and seemingly sustainable solution to meet production targets as well as maintaining the environmental quality by use of less quantity of raw materials and active ingredients, increased nutrient use-efficiency by plants, and decreased environmental losses of nutrients. However, the use of nanofertilizers has so far been limited largely to controlled environments of laboratories, greenhouses, and institutional research experiments; production and availability on large scale are still lagging yet catching up fast. Despite perceivable advantages, the use of nanofertilizers is many times debated for adoption at a large scale. The scenario is gradually changing, worldwide, towards the use of nanofertilizers, especially macronutrients like nitrogen (e.g. market release of nano-urea to replace conventional urea in South Asia), to arrest environmental degradation and uphold vital ecosystem services which are in critical condition. This review offers a discussion on the purpose with which the nanofertilizers took shape, the benefits which can be achieved, and the challenges which nanofertilizers face for further development and real-world use, substantiated with the significant pieces of scientific evidence available so far.

A Perspective on Reproductive Toxicity of Metallic Nanomaterials

Nanotechnological tools have been greatly exploited in all possible fields. However, advancement of nanotechnology has raised concern about their adverse effects on human and environment. These deleterious effects cannot be ignored and need to be explored due to safety purpose. Several recent studies have demonstrated possible health hazard of nanoparticles on organism. Moreover, studies showed that toxicity of metallic nanomaterial could also lead to reproductive toxicity. Various deleterious effects have demonstrated decreased sperm motility, increased abnormal spermatozoa, altered sperm count, and altered sperm morphology. Morphological and ultrastructural changes also have been reported due to the accumulation of these nanomaterials in reproductive organs. Nonetheless, studies also suggest crossing of metallic nanoparticles through blood testes barrier and generation of oxidative stress which plays major role in reproductive toxicity. In the present study, we have incorporated updated information by gathering all available literature about various metallic nanomaterials and risk related to reproductive system.

PHYSIOLOGICAL AND HISTOLOGICAL STUDY OF THE CALCIUM OXIDE NANOPARTICLES EFFECT ON THE TESTIS OF MALE WISTER RATS

OBJECTIVE

The aim: The study carried out to determine the effect of the Calcium Oxide Nano Particles on the male rats. In this study were used calcium oxide nano powder to enhancing apoptosis in germ cells and disrupting hormonal regulation of reproductive processes in the adult male rats.

PATIENTS AND METHODS

Materials and methods: The experiment using nine male rats, were distributed into three groups. Group one A was doses orally of Calcium Oxide Nano Particles 50 mg/kg of body weight, while group two B was doses orally of Calcium Oxide Nano Particles 100 mg/kg of body weight; also, group three C were a control C group treated with 0.9% saline only, these orally doses continuous 10 days. After 10 days blood samples collected and all rats were euthanatized and the weights, histological changes and hormonal analysis were conducted.

RESULTS

Results: Results show a significantly increased at p<0.05 for both groups A & B compare with control C in weight of testis tissue and the level of testosterone hormone, also histology changes in testis of treatment rats include: necrosis of spermatogonia, primary spermoocyte and spermatids in both groups compared to control group.

CONCLUSION

Conclusions: Through the study, it is recommended to use medium or low doses of CaO NPs that can be used as a testicular tonic and urge it to increase production of the Testosterone hormone.

The Bio-Persistence of Reversible Inflammatory, Histological Changes and Metabolic Profile Alterations in Rat Livers after Silver/Gold Nanorod Administration

As a widely applied nanomaterial, silver nanomaterials (AgNMs) have increased public concern about their potential adverse biological effects. However, there are few related researches on the long-term toxicity, especially on the reversibility of AgNMs in vivo. In the current study, this issue was tackled by exploring liver damage after an intravenous injection of silver nanorods with golden cores (Au@AgNRs) and its potential recovery in a relatively long term (8 w). After the administration of Au@AgNRs into rats, Ag was found to be rapidly cleared from blood within 10 min and mainly accumulated in liver as well as spleen until 8 w. All detected parameters almost displayed a two-stage response to Au@AgNRs administration, including biological markers, histological changes and metabolic variations. For the short-term (2 w) responses, some toxicological parameters (hematological changes, cytokines, liver damages etc.) significantly changed compared to control and AuNRs group. However, after a 6-week recovery, all abovementioned changes mostly returned to the normal levels in the Au@AgNRs group. These indicated that after a lengthy period, acute bioeffects elicited by AgNMs could be followed by the adaptive recovery, which will provide a novel and valuable toxicity mechanism of AgNMs for potential biomedical applications of AgNMs.

Effects of sub-chronic oral exposure to pyrogenic synthetic amorphous silica (NM-203) in male and female Sprague-Dawley rats: focus on reproductive systems

Synthetic amorphous silica (SAS) consists of agglomerates and aggregates of primary particles in the nanorange (<100 nm) and it is the E551 authorized food additive. The potential risks for human health associated to dietary exposure to SAS are not completely assessed; in particular, data on male and female reproductive systems are lacking. A 90-day oral toxicity study with pyrogenic SAS nanomaterial NM-203 was carried out on the basis of the OECD test guideline 408 in the frame of the NANoREG project. Adult Sprague-Dawley rats of both sexes were orally treated for 90 days with 0, 2, 5, 10, 20 and 50 mg SAS/kg bw per day. Dose levels were selected to be as close as possible to the expected human exposure to food additive E551. The present paper provides specific information on potential effects on male and female reproductive systems, through the evaluation of serum biomarkers, sperm count, histopathological analysis of testis, epididymis, ovary and uterus and real-time PCR on uterus; potential genotoxic alterations were evaluated by comet assay on testis, sperm and ovary. NM-203 did not induce histophatological and genotoxic effects in male reproductive system. In female rats, ovary is not target of NM-203 and only tissue-specific effects on uterus were recorded up to 10 mg/kg bw per day. To our best knowledge, this is the first study providing data on male and female reproductive systems after long-term, repeated oral exposure at dose levels close to dietary human exposure, which identifies a limited concern only for female reproductive health.

Alleviation of silver nanoparticle-induced sexual behavior and testicular parameters dysfunction in male mice by yttrium oxide nanoparticles

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Exposure to silver nanoparticles decreased the weight of the reproductive organs, sexual behavior, oxidative defense parameters, sperm count and their motility in male mice.

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In addition, serum testosterone, apoptotic germ cells and testicular histology were also disrupted due to silver nanoparticles.

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Yttrium oxide nanoparticles have protective effects on sexual behavior and spermatotoxicity induced by silver nanoparticles in male mice.

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The toxicity of silver nanoparticles altered testicular functions that were effectively ameliorated by yttrium oxide nanoparticles.

Silver nanoparticles (Ag-NPs) can easily cross through the blood-testis barrier and encourage reproductive dysfunction. This study investigated the protective effects of yttrium oxide nanoparticles (YO-NPs) on sexual behavior and spermatotoxicity induced by Ag-NPs in male mice. Twenty-four male mice were separated into four groups and injected intraperitoneally once a week as the following: group I (Ag-NPs at the dose of 40 mg/kg), group II (YO-NPs at the dose of 40 mg/kg), group III (Ag + YO NPs at the doses of 40 mg/kg, each) and group IV (control; distilled water). After 35 days of the injections, the sexual behavior, oxidative parameters in testis, sperm parameters, serum testosterone, apoptotic germ cells and testicular histology were evaluated. Our findings showed that Ag-NPs decreased the weight of the reproductive organs, sexual behavior, oxidative defense parameters, sperm count and motility of male mice. In addition, the apoptotic cells in testicular cross-sections and TBARS level increased after Ag-NPs exposure when compared to other groups. However, the YO-NPs had protective effects in the studied parameters of testicles and minimized the Ag-NPs toxicity in male mice. In conclusion, the results revealed that the toxicity of Ag-NPS altered testicular functions in male mice that were effectively ameliorated by YO-NPs.

Can nanomaterials induce reproductive toxicity in male mammals? A historical and critical review

The nanotechnology enabled the development of nanomaterials (NMs) with a variety of industrial, biomedical, and consumer applications. However, the mechanism of action (MoA) and toxicity of NMs remain unclear, especially in the male reproductive system. Thus, this study aimed to perform a bibliometric and systematic review of the literature on the toxic effects of different types of NMs on the male reproductive system and function in mammalian models. A series of 236 articles related to the in vitro and in vivo reproductive toxicity of NMs in mammalian models were analyzed. The data concerning the bioaccumulation, experimental conditions (types of NMs, species, cell lines, exposure period, and routes of exposure), and the MoA and toxicity of NMs were summarized and discussed. Results showed that this field of research began in 2005 and has experienced an exponential increase since 2012. Revised data confirmed that the NMs have the ability to cross the blood-testis barrier and bioaccumulate in several organs of the male reproductive system, such as testis, prostate, epididymis, and seminal vesicle. A similar MoA and toxicity were observed after in vitro and in vivo exposure to NMs. The NM reproductive toxicity was mainly related to ROS production, oxidative stress, DNA damage and apoptosis. In conclusion, the NM exposure induces bioaccumulation and toxic effects on male reproductive system of mammal models, confirming its potential risk to human and environmental health. The knowledge concerning the NM reproductive toxicity contributes to safety and sustainable use of nanotechnology.

Toxic and Microbiological Effects of Iron Oxide and Silver Nanoparticles as Additives on Extended Ram Semen

The aim of the study was to investigate the effect of iron oxide (Fe) and silver (Ag) nanoparticles (NPs) on ram semen. A skim milk extender without antibiotics was used as a diluent of 21 ejaculates (8 rams; 2-3 ejaculates/ram). The groups of control (C; semen without NPs), Fe NPs (3.072 mg Fe₃O₄/mL semen), and Ag NPs (2.048 mg Ag-Fe/mL semen) were incubated (15 °C; 30 min), and then a magnetic field was used for NPs' removal. Standard microbiological procedures were performed for all groups. Post-treated samples were stored (15 °C) for 24 h, and sperm variables (kinetics by computer assisted sperm analysis (CASA); viability; morphology; HOST; DNA integrity) were evaluated at 6 and 24 h. Semen data were analyzed by a mixed model for repeated measures and microbiological data with Student's t-test for paired samples. At 6 h of storage, VCL and rapid movement-spermatozoa, and at 24 h, total/progressive motility and amplitude of lateral head displacement (ALH) were significantly decreased in group Ag compared to control. In group Fe, progressive/rapid movement-spermatozoa were significantly lower compared to control after 24 h of storage. Only in group Ag was a significant reduction of total bacterial count revealed. In conclusion, the examined Fe NPs demonstrated slight antibacterial effect, while the examined Ag NPs provided higher antibacterial properties accompanied by cytotoxicity.

Zinc Nanoparticles Ameliorate the Reproductive Toxicity Induced by Silver Nanoparticles in Male Rats

Introduction

Silver nanoparticles (Ag-NPs) are among the most commonly used nanoparticles in different fields. Zinc nanoparticles (Zn-NPs) are known for their antioxidant effect. This study was designed to investigate the adverse effects of Ag-NPs (50 nm) on the male reproductive system and also the ameliorative effect of Zn-NPs (100 nm) against these harmful effects.

Methods

Forty adult male rats were used in this study; they were randomly divided into four equal groups: control group, Ag-NPs group, Zn-NPs group, Ag-NPs + Zn-NPs group. Ag-NPs (50 mg/kg) and/or Zn-NPs (30 mg/kg) were administered orally for 90 days.

Results

The results revealed that exposure to Ag-NPs adversely affected sperm motility, morphology, viability, and concentration. Ag-NPs also induced oxidative stress and lipid peroxidation in testicular tissue. The exposure to Ag-NPs decreased serum FSH, LH, and testosterone hormones. Additionally, comet assay revealed DNA degeneration in the testicular tissue of rats exposed to Ag-NPs. Histopathological examination showed various histological alterations in the testes of rats intoxicated with Ag-NPs. Furthermore, co-administration of Zn-NPs ameliorated most of the toxic effects of Ag-NPs via their antioxidative capacity.

Perspectives of Nanoparticles in Male Infertility: Evidence for Induced Abnormalities in Sperm Production

Advancement in the field of nanotechnology has prompted the need to elucidate the deleterious effects of nanoparticles (NPs) on reproductive health. Many studies have reported on the health safety issues related to NPs by investigating their exposure routes, deposition and toxic effects on different primary and secondary organs but few studies have focused on NPs’ deposition in reproductive organs. Noteworthy, even fewer studies have dealt with the toxic effects of NPs on reproductive indices and sperm parameters (such as sperm number, motility and morphology) by evaluating, for instance, the histopathology of seminiferous tubules and testosterone levels. To date, the research suggests that NPs can easily cross the blood testes barrier and, after accumulation in the testis, induce adverse effects on spermatogenesis. This review aims to summarize the available literature on the risks induced by NPs on the male reproductive system.

The impact of silver nanoparticles phytosynthesized with Viburnum opulus L. extract on the ultrastrastructure and cell death in the testis of offspring rats

AIM

To investigate the effects of prenatal exposure to AgNPs obtained by green synthesis with Viburnum opulus L. extract on the testis in male offspring rats.

MATERIAL AND METHODS

Two different doses of AgNPs (0.8 and 1.5 mg/kg b.w.) and vehicle (PBS) were administered to Wistar female rats on days 3-14 of gestation. At 6 weeks after birth, the ultrastructural changes in correlation with the amount of silver as well as the parameters of oxidative stress, inflammation and cell death mechanisms in the testis of male offspring were evaluated.

RESULTS

AgNPs administered during pregnancy crossed the placental and testicular barriers and induced oxidative stress, DNA damage and autophagy as mechanism of cell toxicity. The markers of inflammation and apoptosis decreased after AgNPs exposure while the NFkB activation increased. TEM examination revealed important ultrastructural changes of Sertoli cells, numerous vacuoles and cytoplasmic changes suggestive of the cell's evolution towards necrosis.

CONCLUSION

Phytoreduced silver nanoparticles with polyphenols from Viburnum opulus L. fruit extract, administered during the embryological development of the male gonad, have testicular toxic effects in offspring even at 6 weeks after birth.

Alterations in reproductive parameters and gene expression in Balb/c mice testes after exposure to silver nanoparticles

Silver nanoparticles (AgNPs) have become one of the most common nanomaterials in various commercial products; however, its potential toxicity to the male reproductive system and the possible mechanisms remains unknown. Our study aimed to investigate the toxicity of silver nanoparticle (AgNPs) in the testis and to elucidate its possible mechanisms. We exposed 6-week-old Balb/c male mice to AgNP daily [0 (control), 30 or 125 mg/kg BW] for 90 days. The histological structure, sperm production and levels of reproductive hormones were assessed; we also observed apoptotic cell nuclei and the ultrastructural characteristics of the testis. Microarray analyses were used to identify differentially expressed genes, and dysregulated apoptosis-related genes and protein were also analysed. Our results indicated that 125 mg/kg AgNP changed testis morphology and decreased sperm production. AgNP treatment also increased apoptosis of germ cells and induced the presence of swollen or dissolved mitochondria in the testis. Microarray analysis showed the expression of 383 genes was altered by AgNP treatment, with apoptosis-related genes showing the greatest changes. Furthermore, we verified dysregulated apoptosis-related genes and proteins (caspase3 and Myc). These results demonstrated that AgNP induced changes of testis morphology, sperm production and apoptosis-related genes, suggested this process maybe associated with apoptosis.

Effects of Dextran-Coated Superparamagnetic Iron Oxide Nanoparticles on Mouse Embryo Development, Antioxidant Enzymes and Apoptosis Genes Expression, and Ultrastructure of Sperm, Oocytes and Granulosa Cells

Background

Although application of superparamagnetic iron oxide nanoparticles (SPIONs) in industry and medicine has increased, their potential toxicity in reproductive cells remains a controversial issue. This study was undertaken to address the response of sperm, oocyte, and resultant blastocyst to dextran-coated SPIONs (D-SPIONs) treatment during murine in vitro fertilization (IVF).

Materials and Methods

In this experimental study, murine mature oocytes were randomly divided into three groups: control, and low- and high-dose groups in which fertilization medium was mixed with 0, 50 and 250 μg/ml of DSPIONs, respectively. Sperm and/or cumulus oocyte complexes (COCs) were cultured for 4 h in this medium for electron microscopic analysis of sperm and COCs, and assessment of developmental competence and genes expression of Gpx1, Sod1, catalase, Bcl2l1 and Bax in the resultant blastocysts.

Results

Ultrastructural study of sperm, oocyte, and granulosa showed destructed mitochondria and membranes in spermatozoa, vacuolated mitochondria and distorted cristae in oocytes, and disrupted nuclei and disorganized cell membranes in granulosa in a dose-dependent manner. Data showed that cleavage and blastocyst rates in the 250 μg/ml of D-SPIONs were significantly lower than in the control group (P<0.05). Gene expression of GPx1, Sod1, catalase, Bcl2l1 and Bax in resultant blastocysts of the high-dose group and catalase and Bax in resultant blastocysts of the low-dose group, was higher than the controls.

Conclusion

There is considerable concern regarding D-SPIONs toxic effects on IVF, and mitochondrial and cell membrane damage in mouse spermatozoa and oocytes, which may be related to oxidative stress and apoptotic events.

Therapeutic effects of rocket seeds (Eruca sativa L.) against testicular toxicity and oxidative stress caused by silver nanoparticles injection in rats

Silver nanoparticles (AgNPs), one of the most well-known nanomaterials, are regularly utilized in everyday consumer products. The present study aimed to investigate the testicular toxicity and oxidative stress by AgNPs and the therapeutic role of the rocket seeds (Eruca sativa) in treatments. Forty male Wistar rats were divided into four equivalent groups (group 1, control; group 2, rocket seeds extract [RS]; group 3, AgNPs; group 4, AgNPs+RS). Our results showed that AgNPs induced a significant decrease in serum total testosterone, FSH (follicle-animating hormone), prolactin and LH (luteinizing hormone), testicular glutathione (GSH), superoxide dismutase (SOD), and glutathione S-transferase (GST). In contrast, a significant increase in testicular DNA, injury, testicular thiobarbituric acid, proliferating cell nuclear antigen, and tumor necrosis factor-α (TNFα) expressions after treatments with AgNPs when contrasted with the control group. Treatments of AgNPs with rocket seeds extract (AgNPs+RS) improved testicular functions and structure. Rocket seeds extract might offer benefits against the toxic nature of AgNPs.

Silver nanoparticles: Synthesis, medical applications and biosafety

Silver nanoparticles (AgNPs) have been one of the most attractive nanomaterials in biomedicine due to their unique physicochemical properties. In this paper, we review the state-of-the-art advances of AgNPs in the synthesis methods, medical applications and biosafety of AgNPs. The synthesis methods of AgNPs include physical, chemical and biological routes. AgNPs are mainly used for antimicrobial and anticancer therapy, and also applied in the promotion of wound repair and bone healing, or as the vaccine adjuvant, anti-diabetic agent and biosensors. This review also summarizes the biological action mechanisms of AgNPs, which mainly involve the release of silver ions (Ag+), generation of reactive oxygen species (ROS), destruction of membrane structure. Despite these therapeutic benefits, their biological safety problems such as potential toxicity on cells, tissue, and organs should be paid enough attention. Besides, we briefly introduce a new type of Ag particles smaller than AgNPs, silver Ångstrom (Å, 1 Å = 0.1 nm) particles (AgÅPs), which exhibit better biological activity and lower toxicity compared with AgNPs. Finally, we conclude the current challenges and point out the future development direction of AgNPs.

Acute reproductive toxicology after intratesticular injection of silver nanoparticles (AgNPs) in Wistar rats

This study aimed to evaluate the effects of an intratesticular injection of silver nanoparticles (AgNPs) on reproductive parameters and health of rats, and to evaluate the AgNPs biodistribution in order to develop a nanotechnological contraceptive agent for male animals. Treated animals received 220 μL of AgNPs solution (0.46 µg-Ag/ml) in each testicle and were euthanized: seven, 14, 28, and 56 days after injection. A significant decrease (p < 0.05) in the percentage of motile sperm in D7 (8.8%) was observed, comparing to the control (73.3%), D14 (86.0%), D28 (68.2%), and D56 (90.0%) groups. D7 group also presented a decrease (p < 0.05) in the percentage of normal spermatozoa. Additionally, D7 group showed an increase (p < 0.05) in abnormal midpiece and sperm head morphology compared to the Control group. Seminiferous tubules presented all germline cell types and spermatozoa for all groups. However, D7 group did not present spermatozoa in the epididymis, whereas some spermatozoa and cellular debris were visible in D14 and D28 groups. All animals presented hematological parameters, creatinine, and alanine aminotransferase values within the normal limits for Wistar rats. The percentage of silver found in the liver was always higher than in the other organs analyzed. A pioneering mathematical model is proposed, from which the half-life time of silver in the liver (17 days), spleen (23 days), lungs (30 days), and kidneys (35 days) was extracted. In conclusion, some acute and severe toxic effects were observed in sperm cells following intratesticular injection of AgNPs, although these effects were reversible. No adverse effects to general animal health were observed.

Toxicity and antimicrobial effect of silver nanoparticles in swine sperms

Bacterial contamination in swine semen affects the quality and longevity of sperm and consequently fertility is reduced. Antibiotics have been used to prevent bacterial growth, but the frequency of bacterial resistance to various antibiotics are increasing. Silver nanoparticles (AgNPs) of 10-20 nm in size have shown a biocide effect in bacteria and fungi microorganisms without toxicity to certain mammalian cells. The goal of this study was to analyze both, antimicrobial activity against Staphylococcus aureus and toxicity in swine sperms after 10-20 nm AgNPs treatment. S. aureus proliferation decreased when concentrations from 0.4 to 10 mM AgNPs were assayed. Also, sperm viability measured by mitochondrial metabolism after AgNPs treatment up to a concentration of 10 mM, was viable. In addition, viability determined by membrane integrity of sperms showed that AgNPs treatment up to a concentration of 10 mM was safe. Sperm morphology was evaluated by automated quantification of proximal and distal drops and whiptails. Data indicated that AgNPs treatment up to a concentration of 4 mM were harmless. Finally, sperm capacitation and acrosome reactions were determined by (chlortetracycline) CTC assay. Data showed that no changes in sperm capacitation were observed when sperms were treated with 2 mM of AgNPs, but data showed increased calcium mobilization when treated with 10 mM AgNPs, which suggested sperm capacitation. Finally, there were no significant changes encountered on sperm acrosome reaction for any of the treatments after AgNPs treatment. Taken together, these results show the potential of AgNPs as an alternative to conventional antimicrobial agents that are currently used in extenders to preserve semen required for storage.

ABBREVIATIONS

AgNPs: silver nanoparticles; AMK: amikacin; AMP: adenosine monophosphate; AR: acrosome reaction; C: capacitation; CF: cefallotin; CFU: colony-forming unit; CTC: chlortetracycline; CXM: cefuroxime; DMSO: dimethyl sulfoxide; NC: non-capacitation; NOM: Norma Oficial Mexicana; PBS: phosphate buffered saline; RLUs: relative light units; ROS: reactive oxygen species; SQS: Seminal Quality System.

Gamete quality in a multistressor environment

Over the past few decades, accumulated evidence confirms that the global environment conditions are changing rapidly. Urban industrialization, agriculture and globalization have generated water, air and soil pollution, giving rise to an environment with a growing number of stress factors, which has a serious impact on the fitness, reproduction and survival of living organisms. The issue raises considerable concern on biodiversity conservation, which is now at risk: it is estimated that a number of species will be extinct in the near future. Sexual reproduction is the process that allows the formation of a new individual and is underpinned by gamete quality defined as the ability of spermatozoa and oocytes to interact during fertilization leading to the creation and development of a normal embryo. This review aimed to provide the current state of knowledge regarding the impact of a broad spectrum of environmental stressors on diverse parameters used to estimate and evaluate gamete quality in humans and in canonical animal models used for experimental research. Effects of metals, biocides, herbicides, nanoparticles, plastics, temperature rise, ocean acidification, air pollution and lifestyle on the physiological parameters that underlie gamete fertilization competence are described supporting the concept that environmental stressors represent a serious hazard to gamete quality with reproductive disorders and living organism failure. Although clear evidence is still limited, gamete capacity to maintain and/or recover physiological conditions is recently demonstrated providing further clues about the plasticity of organisms and their tolerance to the pressures of pollution that may facilitate the reproduction and the persistence of species within the scenario of global change. Changes in the global environment must be urgently placed at the forefront of public attention, with a massive effort invested in further studies aimed towards implementing current knowledge and identifying new methodologies and markers to predict impairment of gamete quality.

Health Impact of Silver Nanoparticles: A Review of the Biodistribution and Toxicity Following Various Routes of Exposure

Engineered nanomaterials (ENMs) have gained huge importance in technological advancements over the past few years. Among the various ENMs, silver nanoparticles (AgNPs) have become one of the most explored nanotechnology-derived nanostructures and have been intensively investigated for their unique physicochemical properties. The widespread commercial and biomedical application of nanosilver include its use as a catalyst and an optical receptor in cosmetics, electronics and textile engineering, as a bactericidal agent, and in wound dressings, surgical instruments, and disinfectants. This, in turn, has increased the potential for interactions of AgNPs with terrestrial and aquatic environments, as well as potential exposure and toxicity to human health. In the present review, after giving an overview of ENMs, we discuss the current advances on the physiochemical properties of AgNPs with specific emphasis on biodistribution and both in vitro and in vivo toxicity following various routes of exposure. Most in vitro studies have demonstrated the size-, dose- and coating-dependent cellular uptake of AgNPs. Following NPs exposure, in vivo biodistribution studies have reported Ag accumulation and toxicity to local as well as distant organs. Though there has been an increase in the number of studies in this area, more investigations are required to understand the mechanisms of toxicity following various modes of exposure to AgNPs.

Silver Nanoparticles Stimulates Spermatogenesis Impairments and Hematological Alterations in Testis and Epididymis of Male Rats

The potential pharmaceutical application of nanoparticles has led to the toxicity within the male reproductive system. In the present study, the effects of silver nanoparticles (Ag-NPs) on hematological parameters, free radical generation, antioxidant system, sperm parameters, and organ histo-morphometry in male rats were investigated. Ag-NPs were produced by the reduction of silver ions, while the formation of which was monitored by UV-visible spectrophotometry. Zeta potential, transmission, and scanning electron microscopies were applied for the characterization of AgNPs. A total of 30 rats were divided into 6 groups and were sub-dermally exposed to Ag-NPs at the dosage of 0 (control), 10, and 50 mg/kg bodyweight (bw) doses for either 7 or 28 days. Ag-NP administration altered hematological indices and caused dose-dependent decreases in sperm motility, velocity, kinematic parameters, concentrations of luteinizing hormone, follicle-stimulating hormone, and testosterone. In the epididymis and testis, the concentrations of malondialdehyde and peroxide increases while superoxide dismutase, catalase, reduced glutathione, and total thiol group decreases. These findings suggest that Ag-NP triggered hormonal imbalance and induce oxidative stress in testis and epididymis; which negatively affect sperm parameters of male rats.

Biochemical functionality of magnetic particles as nanosensors: how far away are we to implement them into clinical practice?

Magnetic nanosensors have become attractive instruments for the diagnosis and treatment of different diseases. They represent an efficient carrier system in drug delivery or in transporting contrast agents. For such purposes, magnetic nanosensors are used in vivo (intracorporeal application). To remove specific compounds from blood, magnetic nanosensors act as elimination system, which represents an extracorporeal approach. This review discusses principles, advantages and risks on recent advances in the field of magnetic nanosensors. First, synthesis methods for magnetic nanosensors and possibilities for enhancement of biocompatibility with different coating materials are addressed. Then, attention is devoted to clinical applications, in which nanosensors are or may be used as carrier- and elimination systems in the near future. Finally, risk considerations and possible effects of nanomaterials are discussed when working towards clinical applications with magnetic nanosensors.

Potential adverse effects of nanoparticles on the reproductive system

With the vigorous development of nanometer-sized materials, nanoproducts are becoming widely used in all aspects of life. In medicine, nanoparticles (NPs) can be used as nanoscopic drug carriers and for nanoimaging technologies. Thus, substantial attention has been paid to the potential risks of NPs. Previous studies have shown that numerous types of NPs are able to pass certain biological barriers and exert toxic effects on crucial organs, such as the brain, liver, and kidney. Only recently, attention has been directed toward the reproductive toxicity of nanomaterials. NPs can pass through the blood–testis barrier, placental barrier, and epithelial barrier, which protect reproductive tissues, and then accumulate in reproductive organs. NP accumulation damages organs (testis, epididymis, ovary, and uterus) by destroying Sertoli cells, Leydig cells, and germ cells, causing reproductive organ dysfunction that adversely affects sperm quality, quantity, morphology, and motility or reduces the number of mature oocytes and disrupts primary and secondary follicular development. In addition, NPs can disrupt the levels of secreted hormones, causing changes in sexual behavior. However, the current review primarily examines toxicological phenomena. The molecular mechanisms involved in NP toxicity to the reproductive system are not fully understood, but possible mechanisms include oxidative stress, apoptosis, inflammation, and genotoxicity. Previous studies have shown that NPs can increase inflammation, oxidative stress, and apoptosis and induce ROS, causing damage at the molecular and genetic levels which results in cytotoxicity. This review provides an understanding of the applications and toxicological effects of NPs on the reproductive system.

Perspectives of nanotechnology in male fertility and sperm function

Recent advances in nanotechnology have tremendously expanded its possible applications in biomedicine. Although, the effects of nanoparticles (NPs) at cellular and tissue levels have not been fully understood, some of these biological effects might be employed in assisted reproduction to improve male fertility particularly by enhancing sperm cell quality either in vivo or in vitro. This review summarises the available literature regarding the potential applications of nanomaterials in farm animal reproduction, with a specific focus on the male gamete and on different strategies to improve breeding performances, transgenesis and targeted delivery of substances to a sperm cell. Antioxidant, antimicrobial properties and special surface binding ligand functionalization and their applications for sperm processing and cryopreservation have been reviewed. In addition, nanotoxicity and detrimental effects of NPs on sperm cells are also discussed due to the increasing concerns regarding the environmental impact of the expanding use of nanotechnologies on reproduction.

Role of Endocrine-Disrupting Engineered Nanomaterials in the Pathogenesis of Type 2 Diabetes Mellitus

Nanotechnology has enabled the development of innovative technologies and products for several industrial sectors. Their unique physicochemical and size-dependent properties make the engineered nanomaterials (ENMs) superior for devising solutions for various research and development sectors, which are otherwise unachievable by their bulk forms. However, the remarkable advantages mediated by ENMs and their applications have also raised concerns regarding their possible toxicological impacts on human health. The actual issue stems from the absence of systematic data on ENM exposure-mediated health hazards. In this direction, a comprehensive exploration on the health-related consequences, especially with respect to endocrine disruption-related metabolic disorders, is largely lacking. The reasons for the rapid increase in diabetes and obesity in the modern world remain largely unclear, and epidemiological studies indicate that the increased presence of endocrine disrupting chemicals (EDCs) in the environment may influence the incidence of metabolic diseases. Functional similarities, such as mimicking natural hormonal actions, have been observed between the endocrine-disrupting chemicals (EDCs) and ENMs, which supports the view that different types of NMs may be capable of altering the physiological activity of the endocrine system. Disruption of the endocrine system leads to hormonal imbalance, which may influence the development and pathogenesis of metabolic disorders, particularly type 2 diabetes mellitus (T2DM). Evidence from many in vitro, in vivo and epidemiological studies, suggests that ENMs generally exert deleterious effects on the molecular/hormonal pathways and the organ systems involved in the pathogenesis of T2DM. However, the available data from several such studies are not congruent, especially because of discrepancies in study design, and therefore need to be carefully examined before drawing meaningful inferences. In this review, we discuss the outcomes of ENM exposure in correlation with the development of T2DM. In particular, the review focuses on the following sub-topics: (1) an overview of the sources of human exposure to NMs, (2) systems involved in the uptake of ENMs into human body, (3) endocrine disrupting engineered nanomaterials (EDENMs) and mechanisms underlying the pathogenesis of T2DM, (4) evidence of the role of EDENMs in the pathogenesis of T2DM from in vitro, in vivo and epidemiological studies, and (5) conclusions and perspectives.

Non-Invasive Approaches to Epigenetic-Based Sperm Selection

Since sperm size and form do not necessarily provide information on internal sperm structures, novel sperm markers need to be found in order to conduct assisted reproductive therapies (ART) successfully. Currently, the priority of andrologists is not only to select those sperm able to fertilize the oocyte, but also a high quality of sperm that will guarantee a healthy embryo. Evidence of this shows us the importance of studying sperm intensively on genetic and epigenetic levels, because these could probably be the cause of a percentage of infertility diagnosed as idiopathic. Thus, more attention is being paid to posttranslational modifications as the key for better understanding of the fertilization process and its impact on embryo and offspring. Advances in the discovery of new sperm markers should go hand in hand with finding appropriate techniques for selecting the healthiest sperm, guaranteeing its non-invasiveness. To date, most sperm selection techniques can be harmful to sperm due to centrifugation or staining procedures. Some methods, such as microfluidic techniques, sperm nanopurifications, and Raman spectroscopy, have the potential to make selection gentle to sperm, tracking small abnormalities undetected by methods currently used. The fact that live cells could be analyzed without harmful effects creates the expectation of using them routinely in ART. In this review, we focus on the combination of sperm epigenetic status (modifications) as quality markers, with non-invasive sperm selection methods as novel approaches to improve ART outcomes.

Toxicity of Nanoparticles on the Reproductive System in Animal Models: A Review

In the last two decades, nanotechnologies demonstrated various applications in different fields, including detection, sensing, catalysis, electronics, and biomedical sciences. However, public concerns regarding the well-being of human may hinder the wide utilization of this promising innovation. Although, humans are exposed to airborne nanosized particles from an early age, exposure to such particles has risen dramatically within the last century due to anthropogenic sources of nanoparticles. The wide application of nanomaterials in industry, consumer products, and medicine has raised concerns regarding the potential toxicity of nanoparticles in humans. In this review, the effects of nanomaterials on the reproductive system in animal models are discussed. Females are particularly more vulnerable to nanoparticle toxicity, and toxicity in this population may affect reproductivity and fetal development. Moreover, various types of nanoparticles have negative impacts on male germ cells, fetal development, and the female reproductive system. These impacts are associated with nanoparticle modification, composition, concentration, route of administration, and the species of the animal. Therefore, understanding the impacts of nanoparticles on animal growth and reproduction is essential. Many studies have examined the effects of nanoparticles on primary and secondary target organs, with a concentration on the in vivo and in vitro effects of nanoparticles on the male and female reproductive systems at the clinical, cellular, and molecular levels. This review provides important information regarding organism safety and the potential hazards of nanoparticle use and supports the application of nanotechnologies by minimizing the adverse effects of nanoparticles in vulnerable populations.

In vitro exposure of bull sperm cells to DMSA-coated maghemite nanoparticles does not affect cell functionality or structure

Magnetic nanoparticles can be used in different areas of biology. It is therefore important to know the effects of such nanomaterials on germline cells as they may traverse the blood-testis barrier. This work aimed to evaluate the response of bull sperm after exposure to a magnetic fluid containing DMSA-coated maghemite nanoparticles (MNP-DMSA) in order to determine nanotoxicity. Bull sperm was incubated with MNP-DMSA at final concentrations of 0.06, 0.03 or 0.015 mg Fe/mL. Sperm kinetics, plasma membrane integrity and acrosome reaction were evaluated over a 4 h incubation period. The sperm cells were also evaluated by transmission electron microscopy. Exposure of bull sperm to MNP-DMSA did not affect sperm kinetics or integrity. Neither ultrastructural damage of sperm cells nor uptake of nanoparticles by the spermatozoa was observed. In conclusion, MNP-DMSA does not affect sperm function or structure under the conditions tested.

A review of reproductive and developmental toxicity of silver nanoparticles in laboratory animals

We summarized significant effects reported in the literature on the reproductive and developmental toxicity of silver nanoparticles (AgNPs) in laboratory animals. AgNPs showed testicular/sperm toxicity in males and ovarian and embryonic toxicity in females. Maternal injection of AgNPs delayed physical development and impaired cognitive behavior in offspring. Ag was accumulated in the testes after administration of AgNPs. AgNPs were identified in the visceral yolk sac after administration during early gestation in mice. Radiolabeled AgNPs were detected in placenta, breast milk, and pre- and postnatal offspring after injection during late gestation in rats. Ag in the ionic form, and possibly also particles, was suggested to be bioavailable. Although this review provides initial information on the potential reproductive and developmental toxicity of AgNPs, data is still very limited. Further studies using state-of-the-art methodologies and the relevant routes and doses for human exposure are required.