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

Intragastric exposure of rats to silver nanoparticles modulates the redox balance and expression of steroid receptors in testes

Nanosilver (AgNPs) is popular nanomaterials used in food industry that makes gastrointestinal tract an essential route of its uptake. The aim of the presented study was to assess the effects of intragastric exposure to AgNPs on redox balance and steroid receptors in the testes of adult Fisher 344 rats. The animals were exposed to 20 nm AgNPs (30 mg/kg bw/day, by gavage) for 7 and 28 days compared to saline (control groups). It was demonstrated that 7-day AgNPs administration resulted in increased level of total antioxidant status (TAS), glutathione reductase (GR) activity, lower superoxide dismutase activity (SOD), decreased glutathione (GSH) level and GSH/GSSG ratio, as well as higher estrogen receptor (ESR2) and aromatase (Aro) protein expression in Leydig cells compared to the 28-day AgNPs esposure. The longer-time effects of AgNPs exposition were associated with increased lipid hydroperoxidation (LOOHs) and decreased SOD activity and androgen receptor protein level. In conclusion, the present study demonstrated the adverse gastrointestinally-mediated AgNPs effects in male gonads. In particular, the short-term AgNPs exposure impaired antioxidant defence with concurrent effects on the stimulation of estrogen signaling, while the sub-chronic AgNPs exposition revealed the increased testicle oxidative stress that attenuated androgens signaling.

Do Nanoparticles of Calcium Disodium EDTA Minimize the Toxic Effects of Cadmium in Female Rats?

The present study aims to investigate the ability of CaNa2EDTA (ethylenediaminetetraacetic acid) macroparticles and nanoparticles to treat cadmium-induced toxicity in female rats and to compare their efficacies. Forty rats were divided into 4 equal groups: control, cadmium, cadmium + CaNa2EDTA macroparticles and Cd + CaNa2EDTA nanoparticles. Cadmium was added to the drinking water in a concentration of 30 ppm for 10 weeks. CaNa2EDTA macroparticles and nanoparticles (50 mg/kg) were intraperitoneally injected during the last 4 weeks of the exposure period. Every two weeks, blood and urine samples were collected for determination of urea, creatinine, metallothionein and cadmium concentrations. At the end of the experiment, the skeleton of rats was examined by X-ray and tissue samples from the kidney and femur bone were collected and subjected to histopathological examination. Exposure to cadmium increased the concentrations of urea and creatinine in the serum and the concentrations of metallothionein and cadmium in serum and urine of rats. A decrease in bone mineralization by X-ray examination in addition to various histopathological alterations in the kidney and femur bone of Cd-intoxicated rats were also observed. Treatment with both CaNa2EDTA macroparticles and nanoparticles ameliorated the toxic effects induced by cadmium on the kidney and bone. However, CaNa2EDTA nanoparticles showed a superior efficacy compared to the macroparticles and therefore can be used as an effective chelating antidote for treatment of cadmium toxicity.

Review on fate, transport, toxicity and health risk of nanoparticles in natural ecosystems: Emerging challenges in the modern age and solutions toward a sustainable environment

In today's era, nanoparticles (NPs) have become an integral part of human life, finding extensive applications in various fields of science, pharmacy, medicine, industry, electronics, and communication. The increasing popularity of NP usage worldwide is a testament to their tremendous potential. However, the widespread deployment of NPs unavoidably leads to their release into the environmental matrices, resulting in persistence in ecosystems and bioaccumulation in organisms. Understanding the environmental behavior of NPs poses a significant challenge due to their nanoscale size. Given the current environmental releases of NPs, known negative consequences, and the limited knowledge available for risk management, comprehending the toxicity of NPs in ecosystems is both awaiting and crucial. The present review aims to unravel the potential environmental influences of nano-scaled materials, and provides in-depth inferences of the current knowledge and understanding in this field. The review comprehensively summarizes the sources, fate, transport, toxicity, health risks, and remediation solutions associated with NP pollution in aquatic and soil ecosystems. Furthermore, it addresses the knowledge gaps and outlines further investigation priorities for the sustainable control of NP pollution in these environments. By gaining a holistic understanding of these aspects, we can work toward ensuring the responsible and sustainable use of NPs in today's fast-growing world.

Silver nanoparticle ecotoxicity and phytoremediation: a critical review of current research and future prospects

Silver nanoparticles (AgNPs) are widely used in various industries, including textiles, electronics, and biomedical fields, due to their unique optical, electronic, and antimicrobial properties. However, the extensive use of AgNPs has raised concerns about their potential ecotoxicity and adverse effects on the environment. AgNPs can enter the environment through different pathways, such as wastewater, surface runoff, and soil application and can interact with living organisms through adsorption, ingestion, and accumulation, causing toxicity and harm. The small size, high surface area-to-volume ratio, and ability to generate reactive oxygen species (ROS) make AgNPs particularly toxic. Various bioremediation strategies, such as phytoremediation, have been proposed to mitigate the toxic effects of AgNPs and minimize their impact on the environment. Further research is needed to improve these strategies and ensure their safety and efficacy in different environmental settings.

Nanoparticles-induced potential toxicity on human health: Applications, toxicity mechanisms, and evaluation models

Nanoparticles (NPs) have become one of the most popular objects of scientific study during the past decades. However, despite wealth of study reports, still there is a gap, particularly in health toxicology studies, underlying mechanisms, and related evaluation models to deeply understanding the NPs risk effects. In this review, we first present a comprehensive landscape of the applications of NPs on health, especially addressing the role of NPs in medical diagnosis, therapy. Then, the toxicity of NPs on health systems is introduced. We describe in detail the effects of NPs on various systems, including respiratory, nervous, endocrine, immune, and reproductive systems, and the carcinogenicity of NPs. Furthermore, we unravels the underlying mechanisms of NPs including ROS accumulation, mitochondrial damage, inflammatory reaction, apoptosis, DNA damage, cell cycle, and epigenetic regulation. In addition, the classical study models such as cell lines and mice and the emerging models such as 3D organoids used for evaluating the toxicity or scientific study are both introduced. Overall, this review presents a critical summary and evaluation of the state of understanding of NPs, giving readers more better understanding of the NPs toxicology to remedy key gaps in knowledge and techniques.

Exposure to silver and titanium dioxide nanoparticles at supra-environmental concentrations decreased sperm motility and affected spermatozoa subpopulations in gilthead seabream, Sparus aurata

Marine pollution by nanoparticles (NPs) can be reprotoxic for fish and disturb successful reproduction of wild populations. In gilthead seabream (Sparus aurata), a mild effect on sperm motility was observed after exposure to high concentrations of silver NPs. Considering the great heterogeneity traits within a sperm sample, it is possible that NPs affect spermatozoa accordingly, modulating subpopulation profile. Thus, this work aimed to analyse NP effects in sperm motility in general and considering spermatozoa population structure, using a subpopulation approach. Seabream sperm samples from mature males were exposed for 1 h to increasing concentrations of titanium dioxide (1, 10, 100, 1000 and 10,000 μg L^-1) and silver (0.25, 25 and 250 μg L^-1) NPs, including Ag NP and Ag⁺, dissolved in a non-activating medium (0.9 % NaCl). Concentrations chosen include realistic (10-100 and 0.25 μg L^-1, respectively, for TiO₂ and Ag) and supra-environmental values. The mean particle diameter was determined as 19.34 ± 6.72 and 21.50 ± 8.27 nm in the stock suspension, respectively, for titanium dioxide and silver. After the ex vivo exposure, sperm motility parameters were determined using computer-assisted sperm analysis, and sperm subpopulations were later identified using a two-step cluster analysis. Results revealed a significant reduction in total motility after exposure to the 2 highest concentrations of titanium dioxide NPs, while curvilinear and straight-line velocities were not altered. Exposure to silver NPs (Ag NP and Ag⁺) lowered significantly total and progressive motilities at all concentrations, while curvilinear and straight-line velocities were significantly lower only at the highest concentration. Sperm subpopulations were also affected by the exposure to both titanium dioxide and silver NPs. In both cases, the highest levels of NPs triggered a decrease in the percentage of fast sperm subpopulations (38.2% in TiO₂ 1000 μg L^-1, 34.8.% in Ag NP 250 μg L^-1, and 45.0% in Ag⁺ 250 μg L^-1 vs 53.4% in the control), while an increase on slow sperm subpopulations. A reprotoxic effect was proven for both NPs, but only at supra-environmental concentrations.

Zinc nanoparticles ameliorate oxidative stress and apoptosis induced by silver nanoparticles in the brain of male rats

The current study was conducted to investigate the possible ameliorative role of zinc nanoparticles (Zn NPs) against silver nanoparticles (Ag NPs)-induced oxidative and apoptotic brain damage in adult male rats. Twenty-four mature Wistar rats were randomly and equally divided into four groups: control group, Ag NPs group, Zn NPs group, and Ag NPs + Zn NPs group. Rats were exposed to Ag NPs (50 mg/kg) and/or Zn NPs (30 mg/kg) daily by oral gavage for 12 weeks. The results revealed that exposure to Ag NPs significantly increased malondialdehyde (MDA) content, decreased catalase and reduced glutathione (GSH) activities, downregulated the relative mRNA expression of antioxidant-related genes (Nrf-2 and SOD), and upregulated the relative mRNA expression of apoptosis-related genes (Bax, caspase 3 and caspase 9) in the brain tissue. Furthermore, severe neuropathological lesions with a substantial increase in the caspase 3 and glial fibrillary acidic protein (GFAP) immunoreactivity were observed in the cerebrum and cerebellum of Ag NPs-exposed rats. Conversely, co-administration of Zn NPs with Ag NPs significantly ameliorated most of these neurotoxic effects. Collectively, Zn NPs can be used as a potent prophylactic agent against Ag NPs-induced oxidative and apoptotic neural damage.

Correlation between serum zinc and testosterone: A systematic review

Zinc is a vital trace element for normal function of the living system. In male, zinc is involved in various biological processes, an important function of which is as a balancer of hormones such as testosterone. For this purpose, studies related to the influence of zinc on serum testosterone were selected and summarized, including the effect of dietary zinc deficiency and zinc supplementation on testosterone concentrations. After preliminary searching of papers on databases, 38 papers including 8 clinical and 30 animal studies were included in this review. We concluded that zinc deficiency reduces testosterone levels and zinc supplementation improves testosterone levels. Furthermore, the effect degree of zinc on serum testosterone may vary depending on basal zinc and testosterone levels, zinc dosage form, elementary zinc dose, and duration. In conclusion, serum zinc was positively correlated with total testosterone, and moderate supplementation plays an important role in improving androgen.

Effects of Aluminum Oxide Nanoparticles in the Cerebrum, Hippocampus, and Cerebellum of Male Wistar Rats and Potential Ameliorative Role of Melatonin

Aluminum oxide nanoparticles (Al₂O₃ NPs) have been widely used in vaccine manufacture, food additives, human care products, and cosmetics. However, they also have adverse effects on different organs, including the liver, kidneys, and testes. Melatonin is a potent antioxidant, particularly against metals by forming melatonin-metal complexes. The present study aimed to investigate the protective effects of melatonin against Al₂O₃ NP-induced toxicity in the rat brain. Forty adult male Wistar rats were allocated to four groups: the untreated control (received standard diet and distilled water), Al₂O₃ NP-treated (received 30 mg/kg body weight Al₂O₃ NPs), melatonin and Al₂O₃ NP-treated (received 30 mg/kg body weight Al₂O₃ NPs + 10 mg/kg body weight melatonin), and melatonin-treated (received 10 mg/kg body weight melatonin) groups. All treatments were by oral gavages and administered daily for 28 days. Afterward, the rats were sacrificed, and samples from various brain regions (cerebrum, cerebellum, and hippocampus) were subjected to biochemical, histopathological, and immunohistochemical analyses. Al₂O₃ NPs substantially increased malondialdehyde, β-amyloid 1-42 peptide, acetylcholinesterase, and β-secretase-1 expression, whereas they markedly decreased glutathione levels. Furthermore, Al₂O₃ NPs induced severe histopathological alterations, including vacuolation of the neuropil, enlarged pericellular and perivascular spaces, vascular congestion, neuronal degeneration, and pyknosis. Al₂O₃ NP treatment also resulted in an intense positive caspase-3 immunostaining. Conversely, the administration of melatonin alleviated the adverse effects induced by Al₂O₃ NPs. Therefore, melatonin can diminish the neurotoxic effects induced by Al₂O₃ NPs.

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.

Toxicity of Silver Nanoparticles in the Presence of Zinc Oxide Nanoparticles Differs for Acute and Chronic Exposures in Zebrafish

We assessed the acute toxicity effects (96 h) of silver nanoparticles (Ag NPs) and zinc oxide nanoparticles (ZnO NPs) and chronic (28 d) exposure to Ag NPs, including in combination with ZnO NPs. In the chronic studies, we further assessed the toxicokinetics and bioaccumulation of Ag and the resulting histopathological effects in the gill, intestine, and liver of zebrafish. Co-exposures with ZnO NPs reduced the toxicity of Ag NPs for acute (lethality) but enhanced the toxicity effects (tissue histopathology) for chronic exposures. The histological lesions for both NPs exposures in the gill included necrosis and fusion of lamellae, for the intestine necrosis and degeneration, and in the liver, mainly necrosis. The severity of the histological lesions induced by the Ag NPs was related to the amount of accumulated Ag in the zebrafish organs. The Ag accumulation in different organs was higher in the presence of ZnO NPs in the order of the gill > intestine > liver. Depuration kinetics illustrated the lowest half-life for Ag occurred in the gill and for the combined exposure of Ag with ZnO NPs. Our findings illustrate that in addition to tissue, time, and exposure concentration dependencies, the Ag NPs toxicity can also be influenced by the co-exposure to other NPs (here ZnO NPs), emphasizing the need for more combination exposure effects studies for NPs to more fully understand their potential environmental health risks.

Heavy metal and metalloid - induced reproductive toxicity

Heavy metals and metalloid exposure are among the most common factors responsible for reproductive toxicity in human beings. Several studies have indicated that numerous metals and metalloids can display severe adverse properties on the human reproductive system. Metals like lead, silver, cadmium, uranium, vanadium, and mercury and metalloids like arsenic have been known to induce reproductive toxicity. Moderate to minute quantities of lead may affect several reproductive parameters and even affect semen quality. The ecological and industrial exposures to the various heavy metals and metalloids have disastrous effects on the reproductive system ensuing in infertility. This work emphasizes the mechanism and pathophysiology of the aforementioned heavy metals and metalloids in reproductive toxicity. Additionally, this work aims to cover the classical protective mechanisms of zinc, melatonin, chelation therapy, and other trending methods to prevent heavy metal-induced reproductive toxicity.

Ex vivo exposure to titanium dioxide and silver nanoparticles mildly affect sperm of gilthead seabream (Sparus aurata) - A multiparameter spermiotoxicity approach

Nanoparticles (NP) are potentially reprotoxic, which may compromise the success of populations. However, the reprotoxicity of NP is still scarcely addressed in marine fish. Therefore, we evaluated the impacts of environmentally relevant and supra environmental concentrations of titanium dioxide (TiO₂: 10 to 10,000 μg·L^-1) and silver NP (Ag: 0.25 to 250 μg·L^-1) on the sperm of gilthead seabream (Sparus aurata). We performed short-term direct exposures (ex vivo) and evaluated sperm motility, head morphometry, mitochondrial function, antioxidant responses and DNA integrity. No alteration in sperm motility (except for supra environmental Ag NP concentration), head morphometry, mitochondrial function, and DNA integrity occurred. However, depletion of all antioxidants occurred after exposure to TiO₂ NP, whereas SOD decreased after exposure to Ag NP (lowest and intermediate concentration). Considering our results, the decrease in antioxidants did not indicate vulnerability towards oxidative stress. TiO₂ NP and Ag NP induced low spermiotoxicity, without proven relevant ecological impacts.

Evaluation of the Ameliorative Effect of Zinc Nanoparticles against Silver Nanoparticle-Induced Toxicity in Liver and Kidney of Rats

Silver nanoparticles (Ag-NPs) have various pharmaceutical and biomedical applications owing to their unique physicochemical properties. Zinc (Zn) is an essential trace element, a strong antioxidant, and has a primary role in gene expression, enzymatic reactions, and protein synthesis. The present study aims to explore the toxic effects of Ag-NPs (50 nm) on the liver and kidney of rats and also to evaluate the potential protective effect of Zn-NPs (100 nm) against these adverse effects. Forty adult Sprague-Dawley rats were randomly divided into four equal groups: control group, Ag-NPs group, Zn-NPs group, and Ag-NPs + Zn-NPs group. Ag-NPs (50 mg/kg) and/or Zn-NPs (30 mg/kg) were administered daily by gavage for 90 days. The results showed that exposure to Ag-NPs increased serum ALT, AST, urea, and creatinine. Ag-NPs also induced oxidative stress and lipid peroxidation and increased inflammatory cytokines in hepatic and renal tissues. Moreover, histopathological and immunohistochemical examinations revealed various histological alterations and positive caspase-3 expressions in the liver and kidney following exposure to Ag-NPs. On the other hand, most of these toxic effects were ameliorated by co-administration of Zn-NPs. It was concluded that Ag-NPs have hepatotoxic and nephrotoxic effects in rats via different mechanisms including oxidative stress, inflammation, and apoptosis and that Zn-NPs can be used to alleviate these harmful effects by their antioxidative, anti-inflammatory, and antiapoptotic properties.

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.

Nanotechnology Applications of Flavonoids for Viral Diseases

Recent years have witnessed the emergence of several viral diseases, including various zoonotic diseases such as the current pandemic caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). Other viruses, which possess pandemic-causing potential include avian flu, Ebola, dengue, Zika, and Nipah virus, as well as the re-emergence of SARS (Severe Acute Respiratory Syndrome) and MERS (Middle East Respiratory Syndrome) coronaviruses. Notably, effective drugs or vaccines against these viruses are still to be discovered. All the newly approved vaccines against the SARS-CoV-2-induced disease COVID-19 possess real-time possibility of becoming obsolete because of the development of ‘variants of concern’. Flavonoids are being increasingly recognized as prophylactic and therapeutic agents against emerging and old viral diseases. Around 10,000 natural flavonoid compounds have been identified, being phytochemicals, all plant-based. Flavonoids have been reported to have lesser side effects than conventional anti-viral agents and are effective against more viral diseases than currently used anti-virals. Despite their abundance in plants, which are a part of human diet, flavonoids have the problem of low bioavailability. Various attempts are in progress to increase the bioavailability of flavonoids, one of the promising fields being nanotechnology. This review is a narrative of some anti-viral dietary flavonoids, their bioavailability, and various means with an emphasis on the nanotechnology system(s) being experimented with to deliver anti-viral flavonoids, whose systems show potential in the efficient delivery of flavonoids, resulting in increased bioavailability.

Modified Spirulina maxima Pectin Nanoparticles Improve the Developmental Competence of In Vitro Matured Porcine Oocytes

Simple Summary

Poor in vitro embryo development is a major obstacle in porcine assisted reproduction. In the current study, we utilized modified Spirulina maxima pectin nanoparticles as a supplement to improve porcine in vitro maturation medium. Results showed that modified Spirulina maxima pectin nanoparticles at 2.5 µg/mL improved oocyte maturation in form of first polar body extrusion, reduced oxidative stress, and increased the developmental competence of the oocytes after parthenogenetic activation and somatic cell nuclear transfer. Moreover, the relative transcripts quantification showed significant increase in the pluripotency-associated transcripts in the resultant cloned embryos after modified Spirulina maxima pectin nanoparticles supplementation. Therefore, we provide an optimum in vitro maturation condition to improve the in vitro embryo production in porcine.

Abstract

Molecular approaches have been used to determine metabolic substrates involved in the early embryonic processes to provide adequate culture conditions. To investigate the effect of modified Spirulina maxima pectin nanoparticles (MSmPNPs) on oocyte developmental competence, cumulus–oocyte complexes (COCs) retrieved from pig slaughterhouse ovaries were subjected to various concentrations of MSmPNPs (0, 2.5, 5.0, and 10 µg/mL) during in vitro maturation (IVM). In comparison to the control, MSmPNPs-5.0, and MSmPNPs-10 groups, oocytes treated with 2.5 µg/mL MSmPNPs had significantly increased glutathione (GSH) levels and lower levels of reactive oxygen species (ROS). Following parthenogenetic activation, the MSmPNPs-2.5 group had a considerably higher maturation and cleavage rates, blastocyst development, total cell number, and ratio of inner cell mass/trophectoderm (ICM:TE) cells, when compared with those in the control and all other treated groups. Furthermore, similar findings were reported for the developmental competence of somatic cell nuclear transfer (SCNT)-derived embryos. Additionally, the relative quantification of POU5F1, DPPA2, and NDP52 mRNA transcript levels were significantly higher in the MSmPNPs-2.5 group than in the control and other treated groups. Taken together, the current findings suggest that MSmPNP treatment alleviates oxidative stress and enhances the developmental competence of porcine in vitro matured oocytes after parthenogenetic activation and SCNT.