The in vitro toxicity analysis of titanium dioxide (TiO2) nanoparticles on kinematics and biochemical quality of rainbow trout sperm cells

Effect of different sizes of nanocopper particles on rainbow trout (Oncorhynchus mykiss W.) spermatozoa motility kinematics

In recent years, nanocopper (Cu NPs) has gained attention due to its antimicrobial properties and potential for industrial, agricultural, and consumer applications. But it also has several effects on the aquatic environment. Widespread use of various nanoproducts has raised concerns about impacts of different nanoparticle size on environment and biological objects. Spermatozoa is a model for studying the ecotoxic effects of pollutants on cells and organisms. This study aimed to investigate the effects of different sizes of copper nanoparticles on rainbow trout spermatozoa motility, and to compare their effects with copper ionic solution. Computer assisted sperm analysis (CASA) was used to detect movement parameters at activation of gametes (direct effect) with milieu containing nanocopper of primary particle size of 40-60, 60-80 and 100 nm. The effect of the elements ions was also tested using copper sulfate solution. All products was prepared in concentration of 0, 1, 5, 50, 125, 250, 350, 500, 750, and 1000 mg Cu L-1. Six motility parameters were selected for analysis. The harmful effect of Cu NPS nanoparticle was lower than ionic form of copper but the effect depends on the motility parameters. Ionic form caused complete immobilization (MOT = 0 %, IC100) at 350 mg Cu L-1 whilst Cu NPs solution only decreased the percentage of motile sperm (MOT) up to 76.4 % at highest concentration tested of 1000 mg Cu L-1 of 40-60 nm NPs. Cu NPs of smaller particles size had more deleterious effect than the bigger one particularly in percentage of MOT and for curvilinear velocity (VCL). Moreover, nanoparticles decrease motility duration (MD). This may influence fertility because the first two parameters positively correlate with fertilization rate. However, the ionic form of copper has deleterious effect on the percentage of MOT and linearity (LIN), but in some concentrations it slightly increases VCL and MD.

TiO2 nanoparticles affect spermatogenesis and adhesion junctions via the ROS-mediated mTOR signalling pathway in Eriocheir sinensis testes

Recent findings found that TiO₂ nanoparticles (TiO₂-NPs) have male reproductive toxicity. However, few reports have studied the toxicity of TiO₂-NPs in crustaceans. In this study, we first chose the freshwater crustacean Eriocheir sinensis (E. sinensis) to explore the male toxicity of TiO₂-NP exposure and the underlying mechanisms. Three nm and 25 nm TiO₂-NPs at a dose of 30 mg/kg bw induced apoptosis and damaged the integrity of the haemolymph-testis-barrier (HTB, a structure similar to the blood-testis-barrier) and the structure of the seminiferous tubule. The 3-nm TiO₂-NPs caused more severe spermatogenesis dysfunction than the 25-nm TiO₂-NPs. We initially confirmed that TiO₂-NP exposure affected the expression patterns of adherens junctions (α-catenin and β-catenin) and induced tubulin disorganization in the testis of E. sinensis. TiO₂-NP exposure caused reactive oxygen species (ROS) generation and an imbalance of mTORC1-mTORC2 (mTORC1/rps6/Akt levels were increased, while mTORC2 activity was not changed). After using the ROS scavenger NAC to inhibit ROS generation, both the mTORC1-mTORC2 imbalance and alterations in AJs were rescued. More importantly, the mTORC1 inhibitor rapamycin abolished mTORC1/rps6/Akt hyperactivation and partially restored the alterations in AJs and tubulin. Collectively, the mTORC1-mTORC2 imbalance induced by TiO₂-NPs was involved in the mechanism of AJ and HTB disruption, resulting in spermatogenesis in E. sinensis.

Shipping can be achieved but cargo arrives with damage - titanium dioxide nanoparticles affect the DNA of Pacific oyster sperm

Titanium dioxide nanoparticles (TiO₂ NP) were reported to be reprotoxic in humans and fish. However, the effects of these NP on the reproduction of marine bivalves, namely oysters, remain unknown. Thus, a short-term (1 h) direct exposure of sperm of the Pacific oyster (Crassostrea gigas) to two TiO₂ NP concentrations (1 and 10 mg.L-1) was performed, and sperm motility, antioxidant responses, and DNA integrity were evaluated. Although no changes occurred in sperm motility and the activities of the antioxidants, the genetic damage indicator increased at both concentrations, demonstrating that TiO₂ NP affects the DNA integrity of oyster sperm. Although DNA transfer can happen, it does not fulfill its biological mission since the transferred DNA is not intact and may compromise the reproduction and recruitment of the oysters. This vulnerability of C. gigas sperm towards TiO₂ NP highlights the importance of studying the effects of NPs exposure to broadcast spawners.

The Cytotoxicity, DNA Fragmentation, and Decreasing Velocity Induced By Chromium(III) Oxide on Rainbow Trout Spermatozoa

The present study aimed to determine the cytotoxicity of chromium(III) oxide micro particles (Cr₂O₃-Ps) in rainbow trout (Oncorhynchus mykiss) spermatozoa. Firstly, Cr₂O₃-Ps were synthesized and structurally characterized the surface, morphological for particle size and thermal properties. In addition, its structural and elemental purity was determined using energy-dispersive X-ray (EDX) spectrum and elemental maps. Structural purity, thermal properties, and stability of Cr₂O₃-Ps were also examined in detail by performing thermal analysis techniques. The cytotoxicity of Cr₂O₃-Ps was measured by the observation of velocities, antioxidant activities, and DNA damages in rainbow trout spermatozoa after exposure during 3 h in vitro incubation. The straight line velocity (VSL), the curvilinear velocity (VCL), and the angular path velocity (VAP) of spermatozoa decreased after exposure to Cr₂O₃-Ps. While the superoxide dismutase (SOD) and the catalase (CAT) decreased, the lipid peroxidation increased in a dose-dependent manner. However, the total glutathione (tGSH) was not affected in this period. DNA damages were also determined in spermatozoa using Comet assay. According to DNA in tail (%) data, DNA damages have been detected with gradually increasing concentrations of Cr₂O₃-Ps. Furthermore, all of class types which are categorized as the intensity of DNA fragmentation has been observed between 50 and 500 µg/L concentrations of Cr₂O₃-Ps exposed to rainbow trout spermatozoa. At the end of this study, we determined that the effective concentrations (EC50) were 76.67 µg/L for VSL and 87.77 µg/L for VCL. Finally, these results about Cr₂O₃-Ps may say to be major risk concentrations over 70 µg/L for fish reproduction in aquatic environments.

The Effect of Copper and Copper Oxide Nanoparticles on Rainbow Trout (Oncorhynchus mykiss W.) Spermatozoa Motility after Incubation with Contaminants

The study aimed to analyse the effect of copper nanoparticles of similar particle size of Cu and CuO and copper ions (CuSO4) on the motility parameters of rainbow trout spermatozoa after long-term exposure and compare its harmful effect. Nanoproducts of Cu and CuO (Cu NPs, CuO NPs) of primary particle size around 50 nm and ionic solution of CuSO4 were used for the study. Suspension of concentrations 0, 1, 5, 10, 25, and 50 mg Cu·L−1 of Cu NPs, CuO NPs, and CuSO4 was dissolved in an artificial seminal plasma. Milt was mixed with the prepared solution and stored in a fridge, at 6 °C, for 96 h. At the defined incubation time, spermatozoa were activated for movement, and six motility parameters were evaluated using an automated system (CASA). Increasing concentrations of Cu NPs, CuO NPs, and CuSO4 in an incubation medium in parallel decreased the percentage of motile sperm (MOT). The effect of Cu NPs and ionic copper on MOT was more deleterious than that of CuO NPs. Copper products slightly increased the velocity (VCL) compared to the control, particularly up to 24 h of storage. Linearity (LIN) was improved by three tested products, particularly CuO NPs. Generally, the motility duration was prolonged when the sperm was incubated with copper products compared to the control. Nanoproducts made from different compounds of the same elements of similar particle size have a different effect on cells. Cu NPs were more harmful than CuO NPs. The effect of Cu NPs was similar to an ionic form of CuSO4. When incubated, the copper nanoproducts and ionic form exert a slightly positive effect on spermatozoa velocity, linearity, and motility duration, particularly up to 24 h of storage.

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.

Spatiotemporal Small Non-coding RNAs Expressed in the Germline as an Early Biomarker of Testicular Toxicity and Transgenerational Effects Caused by Prenatal Exposure to Nanosized Particles

In recent years, an apparent decline in human sperm quality has been observed worldwide. One in every 5.5 couples suffers from infertility, with male reproductive problems contributing to nearly 40% of all infertility cases. Although the reasons for the increasing number of infertility cases are largely unknown, both genetic and environmental factors can be contributing factors. In particular, exposure to chemical substances during mammalian male germ cell development has been linked to an increased risk of infertility in later life owing to defective sperm production, reproductive tract obstruction, inflammation, and sexual disorders. Prenatal exposure to nanomaterials (NMs) is no exception. In animal experiments, maternal exposure to NMs has been reported to affect the reproductive health of male offspring. Male germ cells require multiple epigenetic reprogramming events during their lifespan to acquire reproductive capacity. Given that spermatozoa deliver the paternal genome to oocytes upon fertilization, we hypothesized that maternal exposure to NMs negatively affects male germ cells by altering epigenetic regulation, which may in turn affect embryo development. Small non-coding RNAs (including microRNAs, PIWI-interacting RNAs, tRNA-derived small RNAs, and rRNA-derived small RNAs), which are differentially expressed in mammalian male germ cells in a spatiotemporal manner, could play important regulatory roles in spermatogenesis and embryogenesis. Thus, the evaluation of RNAs responsible for sperm fertility is of great interest in reproductive toxicology and medicine. However, whether the effect of maternal exposure to NMs on spermatogenesis in the offspring (intergenerational effects) really triggers multigenerational effects remains unclear, and infertility biomarkers for evaluating paternal inheritance have not been identified to date. In this review, existing lines of evidence on the effects of prenatal exposure to NMs on male reproduction are summarized. A working hypothesis of the transgenerational effects of sperm-derived epigenomic changes in the F1 generation is presented, in that such maternal exposure could affect early embryonic development followed by deficits in neurodevelopment and male reproduction in the F2 generation.

Evaluation of Zebrafish DNA Integrity after Individual and Combined Exposure to TiO2 Nanoparticles and Lincomycin

Environmental contamination by nanoparticles (NPs) and drugs represents one of the most debated issues of the last years. The aquatic biome and, indirectly, human health are strongly influenced by the negative effects induced by the widespread presence of pharmaceutical products in wastewater, mainly due to the massive use of antibiotics and inefficient treatment of the waters. The present study aimed to evaluate the harmful consequences due to exposure to antibiotics and NPs, alone and in combination, in the aquatic environment. By exploiting some of their peculiar characteristics, such as small size and ability to bind different types of substances, NPs can carry drugs into the body, showing potential genotoxic effects. The research was conducted on zebrafish (Danio rerio) exposed in vivo to lincomycin (100 mg/L) and titanium dioxide nanoparticles (TiO₂ NPs) (10 µg/L) for 7 and 14 exposure days. The effects on zebrafish were evaluated in terms of cell viability, DNA fragmentation, and genomic template stability (GTS%) investigated using Trypan blue staining, TUNEL assay, and the random amplification of polymorphic DNA PCR (RAPD PCR) technique, respectively. Our results show that after TiO₂ NPs exposure, as well as after TiO₂ NPs and lincomycin co-exposure, the percentage of damaged DNA significantly increased and cell viability decreased. On the contrary, exposure to lincomycin alone caused only a GTS% reduction after 14 exposure days. Therefore, the results allow us to assert that genotoxic effect in target cells could be through a synergistic effect, also potentially mediated by the establishment of intermolecular interactions between lincomycin and TiO₂ NPs.

Dynamic modelling of tetrazolium-based microbial toxicity assay-a parametric proxy of traditional dose-response relationship

Microbial toxicity of test substances in tetrazolium assay is often quantified while referring to their IC₅₀ values. However, the implication of such an estimate is very limited and can differ across studies depending on prevailing test conditions. In this work, a factorial design-based end-point microbial toxicity assay was performed, which suggests a significant interaction (P= 0.041) between inoculum and tetrazolium dose on formazan production. Subsequently, a dynamic model framework was utilized to capture the nonlinearities in biomass, substrate, formazan profiles and to project the toxicant inhibition parameter as a robust alternative to IC₅₀ value. Microbial growth, glucose uptake and formazan production in the presence or absence of toxicant (Cu²⁺) from designed batch experiments were used for sequential estimation of model parameters, and their confidence intervals. A logistic growth model with multiplicative inhibition terms for formazan content and toxicant concentration fits the experimental data reasonably well (R²>0.96). Dynamic relative sensitivity analysis revealed that both microbial growth and formazan production profiles were sensitive to toxicant inhibition parameter. The modelling framework not only provides a better insight into the underlying toxic effect but also offers a stable toxicity index for the test substances that can be extended to design a versatile, robust in vitro assay system.

Developments in the Application of Nanomaterials for Water Treatment and Their Impact on the Environment

Nanotechnology is an uppermost priority area of research in several nations presently because of its enormous capability and financial impact. One of the most promising environmental utilizations of nanotechnology has been in water treatment and remediation where various nanomaterials can purify water by means of several mechanisms inclusive of the adsorption of dyes, heavy metals, and other pollutants, inactivation and removal of pathogens, and conversion of harmful materials into less harmful compounds. To achieve this, nanomaterials have been generated in several shapes, integrated to form different composites and functionalized with active components. Additionally, the nanomaterials have been added to membranes that can assist to improve the water treatment efficiency. In this paper, we have discussed the advantages of nanomaterials in applications such as adsorbents (removal of dyes, heavy metals, pharmaceuticals, and organic contaminants from water), membrane materials, catalytic utilization, and microbial decontamination. We discuss the different carbon-based nanomaterials (carbon nanotubes, graphene, graphene oxide, fullerenes, etc.), and metal and metal-oxide based nanomaterials (zinc-oxide, titanium dioxide, nano zerovalent iron, etc.) for the water treatment application. It can be noted that the nanomaterials have the ability for improving the environmental remediation system. The examination of different studies confirmed that out of the various nanomaterials, graphene and its derivatives (e.g., reduced graphene oxide, graphene oxide, graphene-based metals, and graphene-based metal oxides) with huge surface area and increased purity, outstanding environmental compatibility and selectivity, display high absorption capability as they trap electrons, avoiding their recombination. Additionally, we discussed the negative impacts of nanomaterials such as membrane damage and cell damage to the living beings in the aqueous environment. Acknowledgment of the possible benefits and inadvertent hazards of nanomaterials to the environment is important for pursuing their future advancement.

Melatonin protects sperm cells of Capoeta trutta from toxicity of titanium dioxide nanoparticles

In this study, it was aimed to determine the protective effects of melatonin (0.01, 0.1, and 1 mM) against 10 mg/L titanium dioxide nanoparticles (TiO2-NPs) on kinematic and oxidative indices in the sperm cells of Capoeta trutta. Therefore, TiO2 nanoparticles were synthesized primarily within the scope of the study. The synthesized nanoparticles were characterized by structurally different techniques. Then, melatonin and TiO2 were applied to Capoeta trutta sperm cells by in vitro. According to our data, all doses of melatonin showed protective effects on all velocities of sperm cells such as the straight line velocity (VSL), the curvilinear velocity (VCL), and the angular path velocity (VAP) against TiO2-NPs, while 0.1 and 1 mM doses of melatonin improved the VSL value. Although TiO2-NPs increased total glutathione (tGSH), malondialdehyde (MDA) lipid peroxidation, and superoxide dismutase (SOD) compared to the control group, there were positive treatment effects for all doses of melatonin on antioxidant capacity of sperm cells. At the end of this research, it is suggested that over 0.1 mM dose of melatonin improves the velocity of sperm cells and it plays a protective role against the toxic effects of TiO2-NPs.

Synthesis of Nanoporous TiO2 with the Use of Diluted Hydrogen Peroxide Solution and Its Application in Gas Sensing

The chemical routes of metal oxidation in presence of hydrogen peroxide solutions are tailor-made for the synthesis of biocompatible metal oxide surfaces with clean intermediate and end products, such as oxides, hydroxides, hydrogen and water. The hydrolysis of titanium in hydrogen peroxide solutions is particularly interesting for medical applications, forming micro- and nanoscale titania surfaces. In this paper, the content of the hydrolysis solution is revised, allowing the fabrication of gas sensor devices based on nanoporous titania. Nanopore and microcrack formations were discussed in detail by monitoring the structural changes on the thin film surface with field-emission scanning electron microscopy (FE-SEM). A stable rutile crystalline phase was detected by glancing incidence X-ray diffraction (GI-XRD) measurement after repetitive hydrothermal processes. Electrical conductance measurements were carried out at high temperatures (400–600 °C) under humid airflow (40% RH@20 °C) with the injection of various concentrations of a wide set of test compounds (C2H3N, CO, H2, NO2, C2H6O), to observe the sensing capabilities of the material. Furthermore, the humidity effects on the sensing properties toward H2, CO, and C2H6O have been discussed.

Study of mitochondrial swelling, membrane fluidity and ROS production induced by nano-TiO2 and prevented by Fe incorporation

The potential impact of TiO2 and Fe incorporated TiO2 nanoparticles at the organelle level has been reported. The toxicity of the samples on mitochondria isolated from chicken liver tissue has been examined through mitochondrial swelling, membrane fluidity, ROS generation capacity, and activity of complex II. The toxic effect of TiO2 was prevented by incorporating Fe into the TiO2 matrix at different concentrations. The activity of the succinate dehydrogenase enzyme complex was affected and permeabilization of the mitochondrial inner membrane to H+ and K+ and its alteration in membrane fluidity at 100 μg mL-1 of nano-TiO2 dosage were investigated, which showed significant changes in the anisotropy of DPH-labeled mitochondria. Fe incorporation into the TiO2 matrix makes it more biocompatible by changing its structure and morphology.

Behavior, remediation effect and toxicity of nanomaterials in water environments

In recent years, nanotechnology has been developing continuously. Due to their advantageous huge specific surface areas, microinterface characteristics, remediation ability and potential environmental risks, nanomaterials have become a hot topic in the field of environmental research. With the mass production and use of nanomaterials, they will inevitably be discharged or leaked into the water environment. In this paper, we will describe some typical nanomaterials, such as nanoscale zero valent iron (nZVI), graphene nanomaterials (GNMs), TiO₂ nanoparticles (NPs), ZnO NPs, Fe₃O₄ NPs, carbon nanotubes (CNTs), Ag NPs, and other nanomaterials in water environments, focusing on the positive and negative effects of some nanomaterials in water environments. The remediation function and the impact of nanomaterials in water environments, including behavior of nanomaterials and their toxicity to aquatic organisms will be discussed. This will be of great significance for our subsequent research on nanomaterials.

In vitro genotoxic effects of titanium dioxide nanoparticles (n-TiO2 ) in human sperm cells

Titanium dioxide nanoparticles (TiO₂ -NPs) are one of the most widely engineered nanoparticles used. The study has been focused on TiO ₂ -NPs genotoxic effects on human spermatozoa in vitro. TiO ₂ -NPs are able to cross the blood-testis barrier induced inflammation, cytotoxicity, and gene expression changes that lead to impairment of the male reproductive system. This study presents new data about DNA damage in human sperms exposed in vitro to two n-TiO ₂ concentrations (1 µg/L and 10 µg/L) for different times and the putative role of reactive oxygen species (ROS) as mediators of n-TiO ₂ genotoxicity. Primary n-TiO ₂ characterization was performed by transmission electron microscopy. The dispersed state of the n-TiO ₂ in media was spectrophotometrically determined at 0, 24, 48, and 72 hr from the initial exposure. The genotoxicity has been highlighted by different experimental approaches (comet assay, terminal deoxynucleotidyl transferase dUTP nick end labeling [TUNEL] test, DCF assay, random amplification of polymorphic DNA polymerase chain reaction [RAPD-PCR]). The comet assay showed a statistically significant loss of sperm DNA integrity after 30 min of exposure. Increased threshold of sperm DNA fragmentation was highlighted after 30 min of exposure by the TUNEL Test. Also, the RAPD-PCR analysis showed a variation in the polymorphic profiles of the sperm DNA exposed to n-TiO ₂ . The evidence from the DCF assay showed a statistically significant increase in intracellular ROS linked to n-TiO ₂ exposure. This research provides the evaluation of n-TiO ₂ potential genotoxicity on human sperm that probably occurs through the production of intracellular ROS.

The Toxicity Assessment of Iron Oxide (Fe₃O₄) Nanoparticles on Physical and Biochemical Quality of Rainbow Trout Spermatozoon

The aim of this study was to evaluate the in vitro effect of different doses (50, 100, 200, 400, and 800 mg/L) of Fe₃O₄ nanoparticles (NPs) at 4 °C for 24 h on the kinematics of rainbow trout (Oncorhynchus mykiss, Walbaum, 1792) spermatozoon. Firstly, Fe₃O₄ NPs were prepared at about 30 nm from Iron (III) chloride, Iron (II) chloride, and NH₃ via a co-precipitation synthesis technique. Then, the prepared Fe₃O₄ NPs were characterized by different instrumental techniques for their chemical structure, purity, morphology, surface properties, and thermal behavior. The size, microstructure, and morphology of the prepared Fe₃O₄ NPs were studied by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) spectroscopy, and scanning electron microscopy (SEM) equipped with an energy-dispersive X-ray spectrometer (EDS). The thermal properties of the Fe₃O₄ NPs were determined with thermogravimetric analysis (TGA), differential thermal analysis (DTA), and differential scanning calorimeter (DSC) analysis techniques. According to our results, there were statistically significant (p < 0.05) decreases in the velocities of spermatozoon after treatment with 400 mg/L Fe₃O₄ NPs. The superoxide dismutase (SOD) and catalase (CAT) activities were significant (p < 0.05) decrease after 100 mg/L in after exposure to Fe₃O₄ NPs in 24 h. As the doses of Fe₃O₄ NPs increases, the level of malondialdehyde (MDA) and total glutathione (tGSH) significantly (p < 0.05) increased at doses of 400 and 800 mg/L.

Recent Developments in Food Packaging Based on Nanomaterials

The increasing demand for high food quality and safety, and concerns of environment sustainable development have been encouraging researchers in the food industry to exploit the robust and green biodegradable nanocomposites, which provide new opportunities and challenges for the development of nanomaterials in the food industry. This review paper aims at summarizing the recent three years of research findings on the new development of nanomaterials for food packaging. Two categories of nanomaterials (i.e., inorganic and organic) are included. The synthetic methods, physical and chemical properties, biological activity, and applications in food systems and safety assessments of each nanomaterial are presented. This review also highlights the possible mechanisms of antimicrobial activity against bacteria of certain active nanomaterials and their health concerns. It concludes with an outlook of the nanomaterials functionalized in food packaging.