Mitochondrial Fission in Nickel Nanoparticle-Induced Reproductive Toxicity: An In Vitro GC-1 Cell Study

Reproductive disorders and declining fertility rates are significant public health concerns affecting birth rates and future populations. Male infertility, often due to spermatogenesis defects, may be linked to environmental pollutants like nickel nanoparticles (Ni NPs). Ni NPs are extensively utilized across different industries. Nevertheless, their potential adverse effects cannot be overlooked. Previous studies have linked the reproductive toxicity induced by Ni NPs with disturbances in mitochondrial function. Mitochondrial division/fusion dynamics are crucial to their proper function, yet little is known about how Ni NPs perturb these dynamics and whether such perturbation contributes to the impairment of the male reproductive system. Herein, we demonstrated that the exposure of Ni NPs to the mouse-derived spermatogonia cell line (GC-1 cells) triggered DRP1-mediated mitochondrial division and the enhanced impairment of mitochondria, consequently promoting mitochondria-dependent cell apoptosis. Notably, both the mitochondrial division inhibitor (Mdivi-1) and lentiviral-transfected cells with low expression of Dnm1l-DK in these cells could mitigate the toxic effects induced by Ni NPs, pointing to the potential role of mitochondrial dynamics in Ni NP-induced reproductive toxicity. Collectively, our work contributes to the understanding of the mechanisms by which Ni NPs can impact male reproductive function and identifies mitochondrial division as a potential target for intervention.

Revolutionizing lymph node metastasis imaging: the role of drug delivery systems and future perspectives

The deployment of imaging examinations has evolved into a robust approach for the diagnosis of lymph node metastasis (LNM). The advancement of technology, coupled with the introduction of innovative imaging drugs, has led to the incorporation of an increasingly diverse array of imaging techniques into clinical practice. Nonetheless, conventional methods of administering imaging agents persist in presenting certain drawbacks and side effects. The employment of controlled drug delivery systems (DDSs) as a conduit for transporting imaging agents offers a promising solution to ameliorate these limitations intrinsic to metastatic lymph node (LN) imaging, thereby augmenting diagnostic precision. Within the scope of this review, we elucidate the historical context of LN imaging and encapsulate the frequently employed DDSs in conjunction with a variety of imaging techniques, specifically for metastatic LN imaging. Moreover, we engage in a discourse on the conceptualization and practical application of fusing diagnosis and treatment by employing DDSs. Finally, we venture into prospective applications of DDSs in the realm of LNM imaging and share our perspective on the potential trajectory of DDS development.

Alternative Culture Systems for Bovine Oocyte In Vitro Maturation: Liquid Marbles and Differentially Shaped 96-Well Plates

In vivo-matured oocytes exhibit higher developmental competence than those matured in vitro but mimicking the in vivo environment by in vitro conditions has been challenging. Until now, conventional two-dimensional (2D) systems have been used for in vitro maturation of bovine cumulus-oocytes-complexes (COCs). However, using such systems present certain limitations. Therefore, alternative low-cost methodologies may help to optimize oocyte in vitro maturation. Here, we used two different systems to culture COCs and evaluate their potential influence on embryo development and quality. In the first system, we used treated fumed silica particles to create a 3D microenvironment (liquid marbles; LM) to mature COCs. In the second system, we cultured COCs in 96-well plates with different dimensions (flat, ultra-low attachment round-bottom, and v-shaped 96-well plates). In both systems, the nuclear maturation rate remained similar to the control in 2D, showing that most oocytes reached metaphase II. However, the subsequent blastocyst rate remained lower in the liquid marble system compared with the 96-well plates and control 2D systems. Interestingly, a lower total cell number was found in the resulting embryos from both systems (LM and 96-well plates) compared with the control. In conclusion, oocytes matured in liquid marbles or 96-well plates showed no remarkable change in terms of meiotic resumption. None of the surface geometries influenced embryo development while oocyte maturation in liquid marbles led to reduced embryo development. These findings show that different geometry during maturation did not have a large impact on oocyte and embryo development. Lower embryo production after in vitro maturation in liquid marbles was probably detected because in vitro maturation was performed in serum-free medium, which makes oocytes more sensitive to possible toxic effects from the environment.

Study of the Embryonic Toxicity of TiO2 and ZrO2 Nanoparticles

Currently, the widespread use of TiO₂ and ZrO₂ nanoparticles (NPs) in various industries poses a risk in terms of their potential toxicity. A number of experimental studies provide evidence of the toxic effect of TiO₂ and ZrO₂ NPs on biological objects. In order to supplement the level of knowledge and assess the risks of toxicity and danger of TiO₂ and ZrO₂ NPs, we decided to conduct a comprehensive experiment to study the embryonic toxicity of TiO₂ and ZrO₂ NPs in pregnant rats. For the experiment, mongrel white rats during pregnancy received aqueous dispersions of powders of TiO₂ and ZrO₂ NPs at a dose of 100 mg/kg/day. To characterize the effect of TiO₂ and ZrO₂ NPs on females and the postnatal ontogenesis of offspring, a complex of physiological and biochemical research methods was used. The results of the experiment showed that TiO₂ NPs as ZrO₂ NPs (100 mg/kg per os) cause few shifts of similar orientation in the maternal body. Neither TiO₂ NPs nor ZrO₂ NPs have an embryonic and teratogenic effect on the offspring in utero, but both modify its postnatal development.

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.

Polystyrene nanoplastics exposure caused defective neural tube morphogenesis through caveolae-mediated endocytosis and faulty apoptosis

Growing evidence demonstrated that bioaccumulation of polystyrene nanoplastics (PS-NPs) in various organisms including human beings caused destructive effects on health. Nanoplastics may adversely affect fetal development potentially since they can pass through the placental barrier. However, very little has been known about the embryonic toxicity of polystyrene nanoplastics, especially in embryonic neurulation, the early developmental stage of the fetus, as well as the corresponding mechanisms. In this study, we first observed that 60- or 900-nm PS-NPs (especially 60-nm PS-NPs) could cross mouse placentas and affect developing mice fetuses. To avoid the indirect adverse effects derived from the restricted placenta, we employed early chick embryos as a developmental model to evaluate direct adverse effects of PS-NPs on embryo/fetal development, revealing suppressive effects on embryo development and an increased frequency of congenital abnormalities (especially in the nervous system), including neural tube defects. Thus, we focused on the potential negative effects of PS-NPs on neurulation, the earliest stage of nervous system development. Using caveolin-1 immunofluorescent staining of SH-SY5Y cells exposed to PS-NPs-GFP, we demonstrated that PS-NPs were internalized by SH-SY5Y cells via caveolae-mediated endocytosis. Transmission electron microscopy; LC3B immunofluorescent staining; and Atg7, Atg5, p62 and LC3B western blot results revealed that autophagy was activated in SH-SY5Y cells exposed to PS-NPs. However, PS-NPs were not degraded by the autophagic-lysosomal system given the lack of LAMP1 changes and minimal PS-NPs-GFP and LAMP1 colocalization. Furthermore, the cytoplasmic accumulation of PS-NPs caused faulty apoptotic cell death in SH-SY5Y cells and the developing neural tube as revealed by c-caspase3 immunofluorescent staining. Thus, defective neural tube morphogenesis, as demonstrated by neural tube defects, occurred during embryogenesis in the context of PS-NP exposure.

Comparison of Different Materials for Self-Pressurized Vitrification of Feline Oocytes-First Results

Cryobanking is a crucial part on species conservation. Nowadays, there is no suitable protocol for vitrification of feline oocytes. Self-pressurized rapid freezing of different cell types proved to mimic the advantages of high pressure freezing. As this method could also be applied for gamete rescue under field conditions, the aim here was to analyse the impact of self-pressurized vitrification on feline cumulus-oocyte-complexes (COCs) and to determine the appropriate material. Therefore, COCs of domestic cat were randomly vitrified (n = 189) in metal tubes of different materials: Aluminium, silver, and titanium. No significant differences were found on oocytes' competence after thawing. On average, 44% of the COCs presented normal morphology and 48.2% of them showed a polar body after in vitro maturation (IVM) and were subsequently fertilised. Aluminium tubes were positive on toxicity tests, producing the lowest cleavage rates. Silver tubes showed no toxic effect, but the cleavage rate was lower than with titanium tubes, and a previous association with embryotoxicity and biological alterations makes us aware of its indiscriminate use. Titanium seems to be the only inert material of them, presenting a slightly higher maturation (55.6%) and cleavage (20%) rates. Nevertheless, more studies should follow to increase embryo competence after warming.

Oral Exposure to ZnO Nanoparticles Disrupt the Structure of Bone in Young Rats via the OPG/RANK/RANKL/IGF-1 Pathway

Purpose

To evaluate the effects of ZnO NPs on bone growth in rats and explore the possible mechanisms of action.

Materials and Methods

Three-week-old male rats received ultrapure water or 68, 203, and 610 mg/kg zinc oxide nanoparticles (ZnO NPs) for 28 days, orally.

Results

The high-dosage groups caused significant differences in weight growth rate, body length, and tibia length (P<0.05), all decreasing with increased ZnO NP dosage. There were no significant differences in body mass index (BMI) (P>0.05). The zinc concentration in liver and bone tissue increased significantly with increased ZnO NP dosage (P<0.05). Clearly increased aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels were observed in the 610 mg/kg ZnO NP group (P>0.05), whereas alkaline phosphatase (ALP) increased in the 610 mg/kg ZnO NP group (P<0.05). Significant differences in insulin-like growth factor type 1 (IGF-1) levels and a decrease in calcium (Ca) levels were observed in 203 and 610 mg/kg ZnO NP groups (P<0.05). Phosphorus (P) levels increased and the Ca/P ratio decreased in the 610 mg/kg ZnO NP group (P<0.05). Micro-computed tomography (micro-CT) of the tibia demonstrated signs of osteoporosis, such as decreased bone density, little trabecular bone structure and reduced cortical bone thickness. Micro-CT data further demonstrated significantly decreased bone mineral density (BMD), trabecular number (Tb.N), and relative bone volume (BV/TV) with increasing dosage of ZnO NPs. Osteoprotegerin (OPG) expression and the ratio of OPG to receptor activator of nuclear factor-κB ligand (RANKL) were statistically lower in the 610 mg/kg ZnO NP group (P<0.05), whereas RANKL expression did not change significantly (P>0.05).

Conclusion

We infer that ZnO NPs affect bone growth in young rats directly or indirectly by altering IGF-1 levels. Overall, the results indicate that ZnO NPs promote osteoclast activity and increase bone loss through the OPG/RANK/RANKL/IGF-1 pathway.

Toxicity of Carbon, Silicon, and Metal-Based Nanoparticles to Sea Urchin Strongylocentrotus Intermedius

With the increasing annual production of nanoparticles (NPs), the risks of their harmful influence on the environment and human health are rising. However, our knowledge about the mechanisms of interaction between NPs and living organisms is limited. Prior studies have shown that echinoderms, and especially sea urchins, represent one of the most suitable models for risk assessment in environmental nanotoxicology. To the best of the authors’ knowledge, the sea urchin Strongylocentrotus intermedius has not been used for testing the toxicity of NPs. The present study was designed to determine the effect of 10 types of common NPs on spermatozoa activity, egg fertilization, and early stage of embryo development of the sea urchin S. intermedius. In this research, we used two types of multiwalled carbon nanotubes (CNT-1 and CNT-2), two types of carbon nanofibers (CNF-1 and CNF-2), two types of silicon nanotubes (SNT-1 and SNT-2), nanocrystals of cadmium and zinc sulfides (CdS and ZnS), gold NPs (Au), and titanium dioxide NPs (TiO₂). The results of the embryotoxicity test showed the following trend in the toxicity level of used NPs: Au > SNT-2 > SNT-1 > CdS > ZnS > CNF-2 > CNF-1 > TiO₂ > CNT-1 > CNT-2. This research confirmed that the sea urchin S. intermedius can be considered as a sensitive and stable test model in marine nanotoxicology.

Recent insights on indirect mechanisms in developmental toxicity of nanomaterials

BACKGROUND

Epidemiological and animal studies provide compelling indications that environmental and engineered nanomaterials (NMs) pose a risk for pregnancy, fetal development and offspring health later in life. Understanding the origin and mechanisms underlying NM-induced developmental toxicity will be a cornerstone in the protection of sensitive populations and the design of safe and sustainable nanotechnology applications.

MAIN BODY

Direct toxicity originating from NMs crossing the placental barrier is frequently assumed to be the key pathway in developmental toxicity. However, placental transfer of particles is often highly limited, and evidence is growing that NMs can also indirectly interfere with fetal development. Here, we outline current knowledge on potential indirect mechanisms in developmental toxicity of NMs.

SHORT CONCLUSION

Until now, research on developmental toxicity has mainly focused on the biodistribution and placental translocation of NMs to the fetus to delineate underlying processes. Systematic research addressing NM impact on maternal and placental tissues as potential contributors to mechanistic pathways in developmental toxicity is only slowly gathering momentum. So far, maternal and placental oxidative stress and inflammation, activation of placental toll-like receptors (TLRs), impairment of placental growth and secretion of placental hormones, and vascular factors have been suggested to mediate indirect developmental toxicity of NMs. Therefore, NM effects on maternal and placental tissue function ought to be comprehensively evaluated in addition to placental transfer in the design of future studies of developmental toxicity and risk assessment of NM exposure during pregnancy.

Elemental fingerprint of human amniotic fluids and relationship with potential sources of maternal exposure

BACKGROUND

The impact of nanoparticles we are increasingly exposed to remains largely unknown. Of particular concern is the exposure of pregnant women and potential impact on fetal development. Indeed, many in vitro and in vivo animal studies have shown that nanoparticles are able to cross the placental barrier and induce toxic effects to the fetus. However, little is known in humans.

OBJECTIVE

The aim and originality of this study were to investigate the nanoparticle burden of amniotic fluids in pregnant women. Methods - To that purpose, 100 amniotic fluids collected for clinical purposes were used to determine the nanoparticle quantity and nature by inductively coupled plasma atomic emission spectroscopy (NAMIOTIC, ClinicalTrials.gov Identifier: NCT02720887). Results - The prevalence of patients with a substantial concentration for the essential trace elements Cu, Fe and Zn was high, while that of patients with a substantial concentration of Al, Ag, Be, Co, Cr, Ni, Si, Ti and W was relatively low (under 20 %). It was generally higher in the fraction containing nanoparticles and ions than in the fraction containing micro- and submicroparticles. No correlation was found between the nanoparticle burden and the different potential sources of exposure to nanoparticles (smoking status of the patient, living area, heating source, mode of transport, leisure, use of hygiene products and cosmetics and occupational activities).

CONCLUSION

Our results showing low concentrations and low prevalence of most of the assessed elements in amniotic fluids are reassuring. Further research is needed to draw firm conclusions on the developmental toxicity of engineered nanoparticles in humans but the present paper can provide a useful basis for further evaluation of the fetal toxicity of nanoparticles.

Addressing Nanomaterial Immunosafety by Evaluating Innate Immunity across Living Species

The interaction of a living organism with external foreign agents is a central issue for its survival and adaptation to the environment. Nanosafety should be considered within this perspective, and it should be examined that how different organisms interact with engineered nanomaterials (NM) by either mounting a defensive response or by physiologically adapting to them. Herein, the interaction of NM with one of the major biological systems deputed to recognition of and response to foreign challenges, i.e., the immune system, is specifically addressed. The main focus is innate immunity, the only type of immunity in plants, invertebrates, and lower vertebrates, and that coexists with adaptive immunity in higher vertebrates. Because of their presence in the majority of eukaryotic living organisms, innate immune responses can be viewed in a comparative context. In the majority of cases, the interaction of NM with living organisms results in innate immune reactions that eliminate the possible danger with mechanisms that do not lead to damage. While in some cases such interaction may lead to pathological consequences, in some other cases beneficial effects can be identified.

Effects of In Ovo Supplementation with Nanonutrition (L-Arginine Conjugated with Ag NPs) on Muscle Growth, Immune Response and Heat Shock Proteins at Different Chicken Embryonic Development Stages

Simple Summary

In this study, we have analyzed the effects of in ovo supplementation of inorganic and organic synthesized silver nanoparticles (Ag NPs) conjugated with L-arginine (L-Arg) that were injected in chicken embryo at three different embryonic development stages (8th d, 14th d and 18th d). We investigated the effects of both conjugated Ag NPs on the survival, hatchability and body weight on hatching day (1 d old chicks). The expression of muscle growth related proteins, mainly myoblast determination protein (myoD), myogenin and heat-shock proteins (HSPs) were analyzed in pectoral muscles. The serum level of immunoglobulin M (IgM), serum glutamate oxaloacetate transaminase (SGOT) and serum glutamate pyruvate transaminase (SGPT) were also examined. Our study shows that 14th day of injection of both types of conjugated Ag NPs promoted survival rate and hatching rate at 8 d and 18 d from injection. The immunoglobulin (IgM) levels in serum and the expression of muscle growth related proteins (myoD and myogenin) were dramatically improved; in addition, HSP-60 and HSP-70 expression were declined at 14th d of injection. The serum levels of SGOT and SGPT were decreased at 14d injection when compared to 8 d and 18 d injection. Hence, the 14th day would be suitable day for injection of L-Arg with Ag NPs to promote the survival rate, hatching rate, immune system and muscle growth. Our results illustrated that plant mediated synthesis of Ag NPs at 1000 μg and chemically synthesized Ag NPs at 100 μg concentration would be a better choice to make nanonutrition with L-Arg (100 μg) to carry the nutrients without any toxicity at 14 d injection.

Abstract

The aim of the study was to analyze the in ovo injection of inorganic and organic synthesized silver nanoparticles (Ag NPs) using Brassica oleracea L. var. capitate F. rubra (BOL) conjugation with L-Arginine (L-Arg) on the immune, muscle growth, survivability and hatchability of broiler chickens. The conjugation of L-Arg (100 μg) with 1000 µg of Ag NPs synthesized by (BOL)-extract and L-Arg (100 μg) conjugated with 100 µg of Ag NPs inorganic synthesized were injected into fertile eggs at 8 d, 14 d and 18 d of incubation. Survival and hatching rate were significantly improved in the dose of L-Arg (100 μg) with 1000 µg (BOL-Ag NPs) and L-Arg (100 μg) with 100 µg (C-Ag NPs) on 14 d injection whereas it was decreased on 8 d or 18 d injection. Moreover, the protein expression of muscle development markers such as myogenin and myoD were significantly uprelated in 14 d of incubation whereas the heat shock proteins (HSPs), such as HSP-60 and HSP-70, were significantly upregulated in 18 d incubation. In addition, the liver function marker of serum glutamate oxaloacetate transaminase (SGOT) and serum glutamate pyruvate transaminase (SGPT) were significantly decreased and the immunoglobulin (IgM) levels were increased in a 14 d incubation period in serum at the same concentration.

Extracellular Vesicles Function as Bioactive Molecular Transmitters in the Mammalian Oviduct: An Inspiration for Optimizing in Vitro Culture Systems and Improving Delivery of Exogenous Nucleic Acids during Preimplantation Embryonic Development

Two technologies, in vitro culture and exogenous gene introduction, constitute cornerstones of producing transgenic animals. Although in vitro embryo production techniques can bypass the oviduct during early development, such embryos are inferior to their naturally produced counterparts. In addition, preimplantation embryos are resistant to the uptake of exogenous genetic material. These factors restrict the production of transgenic animals. The discovery of extracellular vesicles (EVs) was a milestone in the study of intercellular signal communication. EVs in the oviduct, known as oviductosomes (OVS), are versatile delivery tools during maternal–embryo communication. In this review, we discuss the important roles of OVS in these interactions and the feasibility of using them as tools for transferring exogenous nucleic acids during early development. We hypothesize that further accurate characterization of OVS cargoes and functions will open new horizons for research on maternal–embryo interactions and enhance the production of transgenic animals.

Characterization and Biological Action of Avermectin Granules on the Moroccan Locust, Dociostaurus maroccanus (Orthoptera: Acrididae)

Granules composed of alfalfa and sunflower meal that were impregnated with avermectins (AVMs) were developed for use against the Moroccan locust, Dociostaurus maroccanus (Thunberg). Laboratory experiments with granules containing 0.15% of AVMs fed to locust nymphs resulted in 100% death within 5 d. The quantification of AVM loss after exposure of AVM-containing preparative forms to UV light for various time periods was performed using high-performance liquid chromatography (HPLC). The results showed no loss of AVMs from the granules after 3 h of their exposure to UV light. The effect of UV radiation on a thin layer of the AVM solution led to the rapid degradation of AVMs. Only 0.2% of the initial AVM amount was detected after 3 h of exposure. In the granulated form, the AVM content remained stable for 10 mo when stored at room temperature in the dark. A method combining solid-phase extraction with HPLC was developed for the quantification of AVMs in locust nymphs. The granulated AVMs are characterized by their high resistance to UVB radiation. The use of plant-based granules impregnated with AVMs can be considered a very promising tool for locust control.

Characterization and toxicology evaluation of zirconium oxide nanoparticles on the embryonic development of zebrafish, Danio rerio

Zirconia oxide nanoparticles (ZrO₂NPs) are known to be one of the neutral bioceramic metal compounds that has been widely used for their beneficial applications in many biomedical areas, in dental implants, bone joint replacements, drug delivery vehicles, and in various industrial applications. To study the effects of ZrO₂NPs on zebrafish model, we used early life stages of the zebrafish (Danio rerio) to examine such effects on embryonic development in this species. ZrO₂NPs were synthesized by the sol-gel method, size about 15-20 nm and characterized by SEM, EDX, XRD, FTIR, UV-Vis Spectra. In this study, zebrafish embryos were treated with ZrO₂NPs 0.5, 1, 2, 3, 4, or 5 μg of nanoparticles/ml during 24-96 hour post fertilization (hpf). The results showed that ≥0.5-1 μg/ml of ZrO₂NPs instigated developmental acute toxicity in these embryos, causing mortality, hatching delay, and malformation. ZrO₂NPs exposure induced axis bent, tail bent, spinal cord curvature, yolk-sac, and pericardial edema. A typical phenotype was observed as an unhatched dead embryo at ≥1 μg/ml of ZrO₂NPs exposure. This study is one of the first reports on developmental toxicity of zebrafish embryos caused by zirconium oxide nanoparticles in aquatic environments. Our results show that exposure of zirconium oxide nanoparticles is more toxic to embryonic zebrafish at lower concentrations. The results will contribute to the current understanding of the potential biomedical toxicological effects of nanoparticles and support the safety evaluation and synthesis of Zirconia oxide nanoparticles.

Interaction of carboxylated CdSe/ZnS quantum dots with fish embryos: Towards understanding of nanoparticles toxicity

Due to colloidal instability even with protective coatings, nanoparticles tend to aggregate in complex environments and possibly interact with biota. In this study, visualization of quantum dots (QDs) interaction with rainbow trout (Oncorhynchus mykiss) embryos was performed. Studies on zebrafish (Danio rerio) and pearl gourami (Trichogaster leerii) embryos have shown that QDs interact with embryos in a general manner and their affects are independent on the type of the embryo. It was demonstrated that carboxylated CdSe/ZnS QDs (4 nM) were aggregating in accumulation media and formed agglomerates on the surface of fish embryos under 1-12 days incubation in deep-well water. Detailed analysis of QDs distribution on fish embryos surface and investigation of the penetration of QDs through embryo's membrane showed that the chorion protects embryos from the penetration through the chorion and the accumulation of nanoparticles inside the embryos. Confocal microscopy and spectroscopy studies on rainbow trout embryos demonstrated that QDs cause chorion damage, due to QDs aggregation on the surface of chorion, even the formation of the agglomerates at the outer part of the embryos and/or with the mucus were detected. Aggregation of QDs and formation of agglomerates on the outer part of the embryo's membrane caused the intervention of the aggregates to the chorion and even partially destroyed the embryo's chorion. The incorporation of QDs in chorion was confirmed by two methods: in living embryos from a 3D reconstruction view, and in slices of embryos from a histology view. The damage of chorion integrity might have adverse effects on embryonic development. Moreover, for the first time the toxic effect of QDs was separated from the heavy metal toxicity, which is most commonly discussed in the literature to the toxicity of the QDs.

Effects of technogenic pollutants on chicken embryos

Increasing interest in nanomaterials can be explained by their broad involvement in many fields of industry and medicine. It is known that carbon black and crysotile asbestos behave like nanosized objects. They are wide spread in environment and have close contact with living organisms. The aim of our study was to define the effects of carbon black and crysotile asbestos on structures of the developing organism.

We used chicken embryos as a model for our study. Total amount of 77 eggs was divided in three groups: one control and two experimental with introduced carbon black and asbestos respectively. Researched materials were injected in the yolk on the third day of incubation and tissues for study were taken during early, middle and late stages of incubation. Histological and electron microscopy methods were used.

Carbon black and asbestos introduction caused underdevelopment of embryos and vessels depletion in blood islands of the yolk sac. Asbestos slowed down angiogenesis. Soot particles caused integrity violation of vessels and led to extravasation. The manifestations of soot influence were damages to blood circulatory system and structural disorders on cellular level. Introduction of chrysotile asbestos mostly resulted in compensatoryadaptive reactions like increasing in hematopoiesis and transcytosis in endotheliocytes.

In-ovo exposed carbon black nanoparticles altered mRNA gene transcripts of antioxidants, proinflammatory and apoptotic pathways in the brain of chicken embryos

With ubiquitous applications of nanotechnology, there are increasing probabilities of exposure to manufactured nanoparticles (NPs), which might be posing emerging health concerns on the next generation. Recent data suggest that generation of reactive oxygen species may play an integral role in the carbon black nanoparticles (CBNPs)-induced oxidative injury; however, the exact molecular mechanism has not been clarified. Hence, the role of oxidative stress, inflammation and apoptosis pathways in the CBNPs-induced neuronal toxicity following in-ovo exposure of chicken embryo was elucidated. Specific pathogen-free fertilized Sasso eggs were inoculated with 4.8, 9.5 and 14 μg CBNPs/egg at the 3rd day of incubation alongside vehicle controls. In a concentration-dependent manner, CBNPs inoculation induced oxidative stress, which was ascertained by enhancement of lipid peroxides and diminishing total antioxidant capacity and glutathione levels, and catalase activity in brain tissues. mRNA transcript levels of antioxidant genes showed up-regulation of heme oxygenase-1 and superoxide dismutase-1, with marked down-regulation of glutathione S-transferase-α. Additionally, the pro-inflammatory genes; nuclear factor-κB1 was up-regulated, while interferon-γ was down-regulated. There is also a clear down-regulation in apoptotic markers caspase-8, caspase-3, cytochrome c and B-cell CLL/lymphoma 2 at the different concentrations, while caspase-2 is up-regulated only at higher concentration. Collectively, these results show that CBNPs exposure-mediated overproduction of the free radicals, particularly at higher concentration contributes to inflammation and subsequent cellular apoptosis at the gene expression level, thus unveiling possible molecular relationship between CBNPs and genes linked to the oxidant, inflammatory and apoptotic responses.

Toxicity studies of six types of carbon nanoparticles in a chicken-embryo model

In the present study, the toxicity of six different types of carbon nanoparticles (CNPs) was investigated using a chicken-embryo model. Fertilized chicken eggs were divided into the following treatment groups: placebo, diamond NPs, graphite NPs, pristine graphene, small graphene oxide, large graphene oxide, and reduced graphene oxide. Experimental solutions at a concentration of 500 μg/mL were administrated into the egg albumin. Gross pathology and the rate of survival were examined after 5, 10, 15, and 20 days of incubation. After 20 days of incubation, blood samples were collected and the weight of the body and organs measured. The relative ratio of embryo survival decreased after treatment all treatments except diamond NPs. There was no correlation between the rate of survival and the ζ-potential or the surface charge of the CNPs in solution. Body and organ weight, red blood-cell morphology, blood serum biochemical parameters, and oxidative damage in the liver did not differ among the groups. These results indicate that CNPs can remain in blood circulation without any major side effects, suggesting their potential applicability as vehicles for drug delivery or active compounds per se. However, there is a need for further investigation of their properties, which vary depending on production methods and surface functionalization.

A critical evaluation of the fish early-life stage toxicity test for engineered nanomaterials: experimental modifications and recommendations

There are concerns that regulatory toxicity tests are not fit for purpose for engineered nanomaterials (ENMs) or need modifications. The aim of the current study was to evaluate the OECD 210 fish, early-life stage toxicity test for use with TiO2 ENMs, Ag ENMs, and MWCNT. Both TiO2 ENMS (≤160 mg l(-1)) and MWCNT (≤10 mg l(-1)) showed limited acute toxicity, whilst Ag ENMs were acutely toxic to zebrafish, though less so than AgNO3 (6-day LC50 values of 58.6 and 5.0 µg l(-1), respectively). Evidence of delayed hatching, decreased body length and increased muscle width in the tail was seen in fish exposed to Ag ENMs. Oedema (swollen yolk sacs) was also seen in fish from both Ag treatments with, for example, mean yolk sac volumes of 17, 35 and 39 µm(3) for the control, 100 µg l(-1) Ag ENMs and 5 µg l(-1) AgNO3 treatments, respectively. Among the problems with the standard test guidelines was the inability to maintain the test solutions within ±20 % of nominal concentrations. Pronounced settling of the ENMs in some beakers also made it clear the fish were not being exposed to nominal concentrations. To overcome this, the exposure apparatus was modified with the addition of an exposure chamber that ensured mixing without damaging the delicate embryos/larvae. This allowed more homogeneous ENM exposures, signified by improved measured concentrations in the beakers (up to 85.7 and 88.1 % of the nominal concentrations from 10 mg l(-1) TiO2 and 50 µg l(-1) Ag ENM exposures, respectively) and reduced variance between measurements compared to the original method. The recommendations include: that the test is conducted using exposure chambers, the use of quantitative measurements for assessing hatching and morphometrics, and where there is increased sensitivity of larvae over embryos to conduct a shorter, larvae-only toxicity test with the ENMs.

Extracellular vesicle-mediated delivery of molecular compounds into gametes and embryos: learning from nature

BACKGROUND

Currently, even the most sophisticated methods of assisted reproductive technology (ART) allow us to achieve live births in only approximately 30% of patients, indicating that our understanding of the fine mechanisms underlying reproduction is far from ideal. One of the main challenges associated with studies of gamete structure and function is that these cells are remarkably resistant towards the uptake of exogenous substances, including 'molecular research tools' such as drugs, biomolecules and intracellular markers. This phenomenon can affect not only the performance of reproductive biology research techniques, but also the outcomes of the in vitro handling of gametes, which forms the cornerstone of ART. Improvement of intra-gamete delivery in a non-aggressive fashion is vital for the investigation of gamete physiology, and the advancement of infertility treatment. In this review, we outline the current state of nanomaterial-mediated delivery into gametes and embryos in vitro, and discuss the potential of a novel exciting drug delivery technology, based upon the use of targeted 'natural' nanoparticles known as extracellular vesicles (EVs), for reproductive science and ART, given the promising emerging data from other fields.

METHODS

A comprehensive electronic search of PubMed and Web of Science databases was performed using the following keywords: 'nanoparticles', 'nanomaterials', 'cell-penetrating peptides', 'sperm', 'oocyte', 'egg', 'embryo', 'exosomes', 'microvesicles', 'extracellular vesicles', 'delivery', 'reproduction', to identify the relevant research and review articles, published in English up to January 2015. The reference lists of identified publication were then scanned to extract additional relevant publications.

RESULTS

Biocompatible engineered nanomaterials with high loading capacity, stability and selective affinity represent a potential versatile tool for the minimally invasive internalization of molecular cargo into gametes and embryos. However, it is becoming increasingly clear that the translation of these experimental tools into clinical applications is likely to be limited by their non-biodegradable nature. To allow the subsequent use of these methodologies for clinical ART, studies should utilize biodegradable delivery platforms, which mimic natural mechanisms of molecular cargo trafficking as closely as possible. Currently, EVs represent the most physiological intracellular delivery tools for reproductive science and medicine. These natural mediators of cell communication combine the benefits of engineered nanomaterials, such as the potential for in vitro production, targeting and loading, with the essential feature of biodegradability.

CONCLUSION

We anticipate that future investigations into the possibility of applying EVs for the intentional intracellular delivery of molecular compounds into gametes and embryos will open new horizons for reproductive science and clinical ART, ultimately leading to improvements in patient care.