Hepatotoxic effects of silver nanoparticles on Clarias gariepinus; Biochemical, histopathological, and histochemical studies

Acute Toxicity, Hematological Profile, and Histopathological Effects of MgO Nanoparticles on Gills, Muscle, Liver of Mrigal, Cirrhinus mrigala

Nanotechnology is an advancing and emerging field of all environmental, medical, and industrial applications. Magnesium oxide nanoparticles have been widely used in medicine, consumer products, industrial products, textiles, ceramics, alleviation of heartburn, stomach ulcers, and bone regeneration. In the present study, acute toxicity (LC50) of MgO nanoparticles and hematological and histopathological changes in Cirrhinus mrigala was analyzed. The lethal concentration for 50% of MgO nanoparticles was 4.2321 mg/L. Hematological parameters such as white blood cells, red blood cells, hematocrit, hemoglobin, platelets, mean corpuscular volume, mean corpuscular hemoglobin, and mean corpuscular hemoglobin concentration, as well as histopathological abnormalities in gills, muscle, and liver were observed on the 7th and 14th days of exposure. The WBC, RBC, HCT, Hb, and platelets count increased on the 14th day of exposure compared to the control and 7th day of exposure. The MCV, MCH, and MCHC levels decreased on the 7th day of exposure compared to the control and increased on the 14th day. Histopathological changes of MgO nanoparticles in gills, muscle, and liver highly damaged in the quantity of 3.6 mg/L compared to 12 mg/L on 7th and 14th days of exposure. This study finds the level of exposure in hematology and histopathological changes in tissues in relation to the exposure of MgO NPs.

Biogenic silver nanoparticles: Synthesis, applications and challenges in food sector with special emphasis on aquaculture

Aquaculture, a rapidly expanding global food sector faces challenges like pathogenic infections, water quality management and sustainability. Silver nanoparticles (AgNPs) have emerged as promising tools in aquaculture due to their antimicrobial, antiviral and antifungal properties. AgNPs offer alternatives to traditional antimicrobial agents. Their small size and unique physicochemical properties enhance antimicrobial activity, effectively inhibiting pathogen growth and reducing disease incidence in aquatic organisms. Additionally, AgNPs can improve water quality by catalyzing the removal of pollutants, heavy metals and nutrients, reducing environmental impacts. Despite their potential benefits, several challenges and knowledge gaps exist in the utilization of AgNPs in aquaculture. Addressing challenges related to regulation, sustainability and environmental impact will be crucial for realizing their full potential in the industry. Therefore, the present review aims to provide insight into the role of AgNPs, its challenges in aquaculture and also highlights key areas for future research.

Toxic and bioaccumulative effects of zinc nanoparticle exposure to goldfish, Carassius auratus (Linnaeus, 1758)

The widespread use of produced metal oxide nanoparticles (NPs) has increased major concerns about their impact on human as well as aquatic animal health. The present study shows that exposure to different concentrations of zinc oxide (ZnO) NPs led to high accumulations of Zn ions in the metabolic organs of fish (liver and gills), resulting in severe oxidative stress in Carassius auratus. The goldfish (C. auratus) was chosen as an aquatic species for the evaluation of the potential toxicity of aqueous ZnO-NPs (Treatments of hemoglobin and neutrophils (0, 0.5, 1, and 1.5 mg L- 1) following 14 days of exposure. A range of histological and hematological factors were examined. Exposure to the NPs produced significant reduction of red blood cell and white blood cell counts, hematocrit) were found to produce no significant differences in lymphocyte, monocyte, and eosinophil counts; as well as the mean corpuscular hemoglobin concentrations index (P > 0.05). Moreover, the results revealed significant alterations in serum biochemical parameters, hepatic enzyme levels, and immune and antioxidant responses; except for total protein and superoxide dismutase (SOD) of C. auratus exposed to ZnO-NPs, particularly at the 1 and 1.5 mg L- 1 concentrations. Fish exposed to 1 and 1.5 mg L-1 ZnO-NPs displayed a significant reduction in alternative complement pathway activity, lysozyme, and total protein contents of mucus compared to those in the control group. The results showed that hepatic SOD and catalase, and gill catalase activity were significantly decreased, and their malondialdehyde levels increased at 1 and 1.5 mg L-1 ZnO-NPs compared to the control group (P < 0.05). Significant accumulations of ZnO-NPs were observed in the liver, kidney, and gill tissues of fish leading to severe histopathological alterations in these organs. These results suggest that water-borne ZnO-NPs can easily accumulate in metabolic organs and lead to oxidative stress and destructive effects on the physiological features of C. auratus.

Long-term exposure to small-sized silica nanoparticles (SiO2-NPs) induces oxidative stress and impairs reproductive performance in adult zebrafish (Danio rerio)

The widespread use of silica nanoparticles (SiO2-NPs) in various industries, including chemical polishing, cosmetics, varnishes, medical, and food products, has increased the risk of their release into aquatic ecosystems. The toxic effects of small-size SiO2-NPs on the reproductive performance of zebrafish (Danio rerio) have yet to be widely studied. This study aimed to investigate the impact of chronic exposure to small-sized (35 ± 6 nm) SiO2-NPs on adult zebrafish through waterborne exposure to concentrations of 5 (SNP5), 10 (SNP10), 15 (SNP15), and 20 (SNP20) μg/L of SiO2-NPs for 28 days. Our results showed that SiO2-NPs significantly impacted several biochemical parameters, including cholesterol, triglycerides, LDL, HDL, total protein, albumin, urea levels, and alkaline phosphatase and aspartate aminotransferase activity. Cortisol and glucose levels in the SNP20 group significantly differed from the control group. All the exposed groups, apart from SNP5, experienced a significant increase in their total immunoglobulin levels and lysozyme activity. While there was a considerable increase in the activity of catalase and superoxide dismutase in all exposed groups, the expression of antioxidant genes did not appear to be affected. Furthermore, the expression level of il8 was significantly higher in SNP5 and SNP10 than in other treatments. Exposure to SiO2-NPs caused a decrease in gonad weight, absolute fecundity, and larval survival rate, particularly in the SNP20 group. The present study indicates that SiO2-NPs can harm zebrafish and thus further research is necessary to assess their health and environmental risks.

Body distribution and ecotoxicological effect of nanoplastics in freshwater fish, Zacco platypus

The increased consumption of plastics worldwide, has led to the emergence of nanoplastics as important environmental pollutants. Despite the presence of nanoplastics in aquatic environments, their effects on ecosystems remain largely unexplored due to the analysis complexity. This study investigated the organ accumulation and toxic effects of 50 nm polystyrene nanoplastics (PS-NPs) in Zacco platypus (Z. platypus; also known as pale chub fish) using pyrolyzer-gas chromatography-mass spectrometry (Pyr-GC/MS). PS-NPs accumulated in Z. platypus' brain, digestive tract, branchia, and liver, causing changes at cellular level. Over a 14-day exposure, the accumulated PS-NPs led to observable changes in fish behavior (e.g., Total traveled distance and maximum velocity). In addition, the oxidative stress in each organ of Z. platypus increased as the exposure concentration of PS-NPs increased. This study shows that accumulation of nanoplastics in fish, resulting in behavioral changes and biochemical toxicity. As the pattern of change magnifies with exposure time and concentration, from a long-term perspective, the influence of nanoplastics on aquatic ecosystems become evident. This underscores the urgency for continuous research into the potential risks of nanoplastics in aquatic ecosystems.

Toxicity assessment of poultry-waste biosynthesized nanosilver in Anabas testudineus (Bloch, 1792) for responsible and sustainable aquaculture development-A multi-biomarker approach

The current study investigates the potential utilization of poultry intestines for the synthesis of stable silver nanoparticles (AgNPs) and their impact on fish physiology. The AgNPs were synthesized and characterized using various analytical techniques. The toxicity of AgNPs on Anabas testudineus was evaluated, determining a 96-h LC50 value of 25.46 mg l-1. Subsequently, fish were exposed to concentrations corresponding to 1/10th, 1/25th, 1/50th, and 1/100th of the estimated LC50 for a duration of 60 days in a sub-acute study. A comprehensive range of biomarkers, including haematological, serum, oxidative stress, and metabolizing markers, were analyzed to assess the physiological responses of the fish. Additionally, histopathological examinations were conducted, and the accumulation of silver in biomarker organs was measured. The results indicate that silver tends to bioaccumulate in all biomarker organs in a dose- and time-dependent manner, except for the muscle tissue, where accumulation initially increased and subsequently decreased, demonstrating the fish's inherent ability for natural attenuation. Analysis of physiological data and integrated biomarker responses reveal that concentrations of 1/10th, 1/25th, and 1/50th of the LC50 can induce stress in the fish, while exposure to 1/100th of the LC50 shows minimal to no stress response. Overall, this study provides valuable insights into the toxicity and physiological responses of fish exposed to poultry waste biosynthesized AgNPs, offering potential applications in aquaculture while harnessing their unique features.

The Effect of Silver Nanoparticles on the Digestive System, Gonad Morphology, and Physiology of Butterfly Splitfin (Ameca splendens)

The aim of this study was to determine the effects of silver nanoparticles (AgNPs) on the morphology and enzymatic activity of butterfly splitfin (Ameca splendens). Individuals of both sexes, aged about five months, were exposed to AgNPs at concentrations of 0 (control group), 0.01, 0.1, and 1.0 mg/dm3 for 42 days. On the last day of the experiment, the fish were euthanized, subjected to standard histological processing (anterior intestine, liver, and gonads), and analysed for digestive enzyme activity in the anterior intestine and oxidative stress markers in the liver. Fish in the AgNP 0.01 and 0.1 groups had the lowest anterior intestinal fold and enterocyte height. However, there were no statistically significant changes in the digestive enzyme activity in the anterior intestine. Analysis of enzymatic activity in the liver showed an increase in superoxide dismutase activity in fish in the AgNP 0.1 group. Histological analyses showed that AgNPs inhibited meiotic divisions at prophase I in a non-linear manner in ovaries and testes. In the AgNP 0.1 and 1.0 groups, the area occupied by spermatocytes was lower compared to the other groups. These results indicate that exposure to AgNPs may lead to disturbances in morphology and enzymatic activity in the liver and intestine and may lead to disruption of reproduction in populations.

Internal Defense System of Mytilus galloprovincialis (Lamarck, 1819): Ecological Role of Hemocytes as Biomarkers for Thiacloprid and Benzo[a]Pyrene Pollution

The introduction of pollutants, such as thiacloprid and benzo[a]pyrene (B[a]P), into the waters of urbanized coastal and estuarine areas through fossil fuel spills, domestic and industrial waste discharges, atmospheric inputs, and continental runoff poses a major threat to the fauna and flora of the aquatic environment and can have a significant impact on the internal defense system of invertebrates such as mussels. Using monoclonal and polyclonal anti-Toll-like receptor 2 (TLR2) and anti-inducible nitric oxide synthetase (iNOS) antibodies for the first time, this work aims to examine hemocytes in the mantle and gills of M. galloprovincialis as biomarkers of thiacloprid and B[a]P pollution and analyze their potential synergistic effect. To pursue this objective, samples were exposed to the pollutants, both individually and simultaneously. Subsequently, oxidative stress biomarkers were evaluated by enzymatic analysis, while tissue changes and the number of hemocytes in the different contaminated groups were assessed via histomorphological and immunohistochemical analyses. Our findings revealed that in comparison to a single exposure, the two pollutants together significantly elevated oxidative stress. Moreover, our data may potentially enhance knowledge on how TLR2 and iNOS work as part of the internal defense system of bivalves. This would help in creating new technologies and strategies, such as biosensors, that are more suitable for managing water pollution, and garnering new details on the condition of the marine ecosystem.

Oxidative stress, genotoxic effects, and other damages caused by chronic exposure to silver nanoparticles (Ag NPs) and zinc oxide nanoparticles (ZnO NPs), and their mixtures in zebrafish (Danio rerio)

This study assessed the oxidative stress impacts of Ag NPs and ZnO NPs and their mixtures in zebrafish (Danio rerio). Zebrafish were exposed to sublethal concentrations of each NP and a mixture for 28 days followed by a 28-day recovery period (without NP exposure) and measurements made on hepatic levels of antioxidant enzymes (CAT, SOD, and GPx), MDA levels, expression of the genes for the Hsp70 and Hsp90, and MT, blood biochemical parameters (total protein, globulin, albumin, AST, ALT, ALP, and LDH), and genotoxicity in erythrocytes (via measurement of micronuclei (MN) and nuclear (NA) abnormalities). There was a tendency for an increase in the variation in the responses of antioxidant defense systems and there were higher MDA levels with increasing exposure concentration of Ag NPs and with increasing exposure time. Total protein, globulin, and albumin decreased during the exposure period, especially on the days of 28. Moreover, levels of AST and LDH increased significantly in the NPs co-exposure treatments, while levels of ALT and ALP significantly decreased. The highest expression levels for these genes occurred on day 14 and in the NPs co-exposure treatments. For exposure to both NPs individually and as a mixture, the frequency of MN and other NA were significantly increased (p < 0.05). During the recovery periods, most of the effects seen were reduced, most notably in the individual NPs treatments. The overall results suggest that the toxic effects of Ag NPs and ZnO NPs in combination significantly increase their toxicity in zebrafish.

Effect of Quercetin Nanoparticles on Hepatic and Intestinal Enzymes and Stress-Related Genes in Nile Tilapia Fish Exposed to Silver Nanoparticles

Recently, nanotechnology has become an important research field involved in the improvement of animals’ productivity, including aquaculture. In this field, silver nanoparticles (AgNPs) have gained interest as antibacterial, antiviral, and antifungal agents. On the other hand, their extensive use in other fields increased natural water pollution causing hazardous effects on aquatic organisms. Quercetin is a natural polyphenolic compound of many plants and vegetables, and it acts as a potent antioxidant and therapeutic agent in biological systems. The current study investigated the potential mitigative effect of quercetin nanoparticles (QNPs) against AgNPs-induced toxicity in Nile tilapia via investigating liver function markers, hepatic antioxidant status, apoptosis, and bioaccumulation of silver residues in hepatic tissue in addition to the whole-body chemical composition, hormonal assay, intestinal enzymes activity, and gut microbiota. Fish were grouped into: control fish, fish exposed to 1.98 mg L−1 AgNPs, fish that received 400 mg L−1 QNPs, and fish that received QNPs and AgNPs at the same concentrations. All groups were exposed for 60 days. The moisture and ash contents of the AgNP group were significantly higher than those of the other groups. In contrast, the crude lipid and protein decreased in the whole body. AgNPs significantly increased serum levels of ALT, AST, total cholesterol, and triglycerides and decreased glycogen and growth hormone (*** p < 0.001). The liver and intestinal enzymes’ activities were significantly inhibited (*** p < 0.001), while the oxidative damage liver enzymes, intestinal bacterial and Aeromonas counts, and Ag residues in the liver were significantly increased (*** p < 0.001, and * p < 0.05). AgNPs also significantly upregulated the expression of hepatic Hsp70, caspase3, and p53 genes (* p < 0.05). These findings indicate the oxidative and hepatotoxic effects of AgNPs. QNPs enhanced and restored physiological parameters and health status under normal conditions and after exposure to AgNPs.

Antibiotic resistance in aquaculture and aquatic organisms: a review of current nanotechnology applications for sustainable management

Aquaculture has emerged as one of the world's fastest-growing food industries in recent years, helping food security and boosting global economic status. The indiscriminate disposal of untreated or improperly managed waste and effluents from different sources including production plants, food processing sectors, and healthcare sectors release various contaminants such as bioactive compounds and unmetabolized antibiotics, and antibiotic-resistant organisms into the environment. These emerging contaminants (ECs), especially antibiotics, have the potential to pollute the environment, particularly the aquatic ecosystem due to their widespread use in aquaculture, leading to various toxicological effects on aquatic organisms as well as long-term persistence in the environment. However, various forms of nanotechnology-based technologies are now being explored to assist other remediation technologies to boost productivity, efficiency, and sustainability. In this review, we critically highlighted several ecofriendly nanotechnological methods including nanodrug and vaccine delivery, nanoformulations, and nanosensor for their antimicrobial effects in aquaculture and aquatic organisms, potential public health risks associated with nanoparticles, and their mitigation measures for sustainable management.

Co-exposure of iron oxide nanoparticles and glyphosate-based herbicide promote liver toxicity in guppy (Poecilia reticulata): A histochemical and ultrastructural approach

Citrate functionalized iron oxide nanoparticles (IONPs) are employed for various purposes-including environmental remediation but the interaction of IONPs with aquatic contaminants is poorly understood. Among those, glyphosate-based herbicides are toxic and affect target organs such as the liver. Evaluations of livers of female Poecilia reticulata by exposures to IONPs at a concentration of 0.3 mg/L were performed with association to: (1) 0.65 mg of glyphosate per litter and (2) 1.3 mg of glyphosate per litter of Roundup Original, and (3) glyphosate P.A at 0.65 mg/L. These associations were carried out progressively, after 7, 14, and 21 days. We detected circulatory disturbances, inflammatory responses, activation of the immune system, regressive changes, and progressive responses with changes in the connective tissue and decreased glycogen reserve from days 14 to 21. Ultrastructural changes in the Disse space and microvilli of hepatocytes indicated decreased contact surface area. In general, the damage was time and concentration dependent, increasing from 7 to 14 days and tending to stabilize from 14 to 21 days. Therefore, herbicide-associated IONPs functioned as xenobiotics inducing intense cellular detoxification processes and activation of hepatic immune responses.

Comparative toxicity of silver nanoparticles and silver nitrate in freshwater fish Oreochromis mossambicus: A multi-biomarker approach

Silver nanoparticles (AgNPs) in the aquatic environment affect ecological repercussions and have fatal impacts on aquatic animals. The current study examined and correlated the toxicity of silver nitrate (AgNO₃) and silver nanoparticles (AgNPs) to the Mozambique tilapia, Oreochromis mossambicus. The comparative toxicity studies were done by exposing O. mossambicus to various doses of AgNO₃ and AgNPs (0, 25, 50, 75, and 100 μg/L) over a 7-day subacute exposure period. AAS analysis was used to detect Ag accumulation, while the histological examination established gill tissue damage. Oxidative stress affects lipid peroxidation (LPO) and protein carbonyl activity (PCA) in the gill tissue. Antioxidant parameters such as glutathione-S-transferase (GST), glutathione peroxidase (GPx), superoxide dismutase (SOD), catalase activity (CAT), and non-enzymatic antioxidants such as metallothionein (MT) and reduced glutathione. The serum in the blood was used to determine non-specific immunological characteristics such as lysozyme (LYZ), myeloperoxidase (MPO), and respiratory burst activity (RBA). The neurotoxic impact of acetylcholine esterase activity (AChE) was investigated in brain tissues. The findings demonstrated that larger concentrations of AgNO₃ than AgNPs improved enzymatic antioxidant activities in the gill tissue. Histological examination of fish gills demonstrated that both AgNPs and AgNO₃ induced telangiectasia and epithelial cell hyperplasia. By increasing the concentration of AgNPs and AgNO₃, the present research demonstrated that silver accumulation leads to inefficient oxidative stress and altered enzymatic and non-enzymatic parameters, leading to cellular damage.

Silver-Nanoparticle- and Silver-Nitrate-Induced Antioxidant Disbalance, Molecular Damage, and Histochemical Change on the Land Slug (Lehmannia nyctelia) Using Multibiomarkers

It is known that silver nanoparticles (Ag NPs) and AgNO3 have harmful effects on the surrounding organisms, which may cause damage to these organisms. Therefore, the aim of this study is to detect damage caused by Ag NPs and silver nitrate to land slugs (Lehmannia nyctelia). In this study, the slugs were exposed to various concentrations of Ag NPs and AgNO3 for 15 days. The biochemical, antioxidant, lipid peroxidation (LPO), DNA fragmentation, and histopathological endpoints were assessed after 15 days of exposure to different concentrations of Ag NPs (0.04, 0.08, 0.4, and 0.8 g/L) and silver nitrate (0.04, 0.08, 0.4, and 0.8 g/L). The results show a significant decrease in total protein, total carbohydrate, superoxide dismutase, and GST and a significant increase in total lipid, LPO, and DNA fragmentation after exposure to Ag NPs and AgNO3 for 15 days compared with the control group. Histopathiological alterations were observed in the digestive glands which were indicated by histochemical staining. We concluded that exposure to AgNO3 and Ag NPs caused oxidative stress, genetic damage and alterations in the profile of muscle proteins and histological structure in L. nyctelia.

New Insights for Exploring the Risks of Bioaccumulation, Molecular Mechanisms, and Cellular Toxicities of AgNPs in Aquatic Ecosystem

Silver nanoparticles (AgNPs) are commonly used in numerous consumer products, including textiles, cosmetics, and health care items. The widespread usage of AgNPs results in their unavoidable discharge into the ecosystem, which pollutes the aquatic, groundwater, sediments, and marine environments. These nanoparticles (NPs) activate the production of free radicals reactive species in aquatic organisms that interrupt the functions of DNA, cause mitochondrial dysfunction, and increase lipid peroxidation, which terminates the development and reproduction both in vivo and in vitro. The life present in the aquatic ecosystem is becoming threatened due to the release and exploitation of AgNPs. Managing the aquatic ecosystem from the AgNP effects in the near future is highly recommended. In this review, we discussed the background of AgNPs, their discharge, and uptake by aquatic organisms, the mechanism of toxicity, different pathways of cytotoxicity, and bioaccumulation, particularly in aquatic organisms. We have also discussed the antimicrobial activities of AgNPs along with acute and chronic toxicity in aquatic groups of organisms.

Hepatoprotective Effect of Silver Nanoparticles at Two Different Particle Sizes: Comparative Study with and without Silymarin

Silver nanoparticles have been used for numerous therapeutic purposes because of their increased biodegradability and bioavailability, yet their toxicity remains questionable as they are known to interact easily with biological systems because of their small size. This study aimed to investigate and compare the effect of silver nanoparticles’ particle size in terms of their potential hazard, as well as their potential protective effect in an LPS-induced hepatotoxicity model. Liver slices were obtained from Sprague Dawley adult male rats, and the thickness of the slices was optimized to 150 μm. Under regulated physiological circumstances, freshly cut liver slices were divided into six different groups; GP1: normal, GP2: LPS (control), GP3: LPS + AgNpL (positive control), GP4: LPS + silymarin (standard treatment), GP5: LPS + AgNpS + silymarin (treatment I), GP6: LPS + AgNpL + silymarin (treatment II). After 24 h of incubation, the plates were gently removed, and the supernatant and tissue homogenate were all collected and then subjected to the following biochemical parameters: Cox2, NO, IL-6, and TNF-α. The LPS elicited marked hepatic tissue injury manifested by elevated cytokines and proinflammatory markers. Both small silver nanoparticles and large silver nanoparticles efficiently attenuated LPS hepatotoxicity, mainly via preserving the cytokines’ level and diminishing the inflammatory pathways. In conclusion, large silver nanoparticles exhibited effective hepatoprotective capabilities over small silver nanoparticles.

Histological and Chemical Analysis of Heavy Metals in Kidney and Gills of Boops boops: Melanomacrophages Centers and Rodlet Cells as Environmental Biomarkers

Industrialization has resulted in a massive increase in garbage output, which is frequently discharged or stored in waterways like rivers and seas. Due to their toxicity, durability, bioaccumulation, and biomagnification, heavy metals (such as mercury, cadmium, and lead) have been identified as strong biological poisons. Their presence in the aquatic environment has the potential to affect water quality parameters and aquatic life in general. Teleosts’ histopathology provides a sensitive indicator of pollutant-induced stress, because their organs have a central role in the transformation of different active chemical compounds in the aquatic environment. In particular, the gills, kidneys, and liver are placed at the center of toxicological studies. The purpose of this study is to examine the morphological changes caused by heavy metals in the kidney and gills of Boops boops, with a focus on melanomacrophages centers (MMCs) and rodlet cells (RCs) as environmental biomarkers, using histological and histochemical stainings (hematoxylin/eosin, Van Gieson trichrome, Periodic Acid Schiff reaction, and Alcian Blue/PAS 2.5), and immunoperoxidase methods. Our findings show an increase of MMCs and RCs linked to higher exposure to heavy metals, confirming the role of these aggregates and cells as reliable biomarkers of potential aquatic environmental changes reflected in fish fauna. The cytological study of RCs and MMCs could be important in gaining a better understanding of the complicated immune systems of teleosts.

Bioaccumulation of Silver and Impairment of Vital Organs in Clarias gariepinus from Co-Exposure to Silver Nanoparticles and Cow Dung Contamination

This study reports the implications of silver nanoparticles (AgNPs) and cow-dung contamination on water quality and oxidative perturbations in antioxidant biomarkers in the exposed Clarias gariepinus. Sixteen samples of C. gariepinus were exposed to fresh-water, 0.75 mg/mL each of AgNPs, cow-dung and a mixture of AgNPs-cow dung dosed water for 10 days. Cow-dung significantly (p < 0.05) depleted dissolved oxygen (DO) and increased biochemical oxygen demand (BOD) by 14% and 75% respectively. The trends of abundance and bioaccumulation of Ag in C. gariepinus exposed to different treatments followed kidney > muscle > gill > liver, implying the kidney was the worst affected organ. The AgNPs significantly (p < 0.05) perturbed vital organs in C. gariepinus by altering activities of antioxidant biomarkers, whereas AgNPs-cow dung had reduced perturbations implying organic matter bound Ag⁺ to reduce toxicity. These results conclude that AgNPs posed a challenging environment for C. gariepinus to thrive.

Selenomethionine alleviated fluoride-induced toxicity in zebrafish (Danio rerio) embryos by restoring oxidative balance and rebuilding inflammation homeostasis

Fish are target organisms that are extremely susceptible to fluoride pollution, and an increase in fluoride load will damage multiple systems of fish. Selenomethionine (Se-Met) at low levels has been reported to alleviate oxidative damage and inflammation caused by toxic substances, but whether it can alleviate fluoride-induced toxicity in zebrafish embryos has not been elucidated. In this study, the intervention effects of Se-Met on developmental toxicity, oxidative stress and inflammation in zebrafish embryos exposed to fluoride were determined. Our results showed that fluoride accumulated in larvae and induced developmental toxicity in zebrafish embryos, caused oxidative damage and apoptosis, increased significantly the MPO and LZM activities and the levels of the inflammation-related genes IL-1β, IL-6, TNF-α, IL-10 and TGF-β. Moreover, fluoride significantly increased the levels of ERK2, JNK, p38 and p65 in MAPKs and NF-κB pathways. Se-Met-treatment alleviated the adverse effects induced by fluoride, and all of the above indicators induced by fluoride returned to near control levels with increasing concentrations and time. However, treatment with Se-Met-alone also markedly increased the levels of IL-6, TNF-α, IL-10, TGF-β, ERK2 and JNK. In short, these data demonstrated that Se-Met-could alleviate fluoride-induced toxicity in zebrafish embryos by restoring oxidative balance and rebuilding inflammation homeostasis, although low levels of Se-Met-alone had certain toxic effects on zebrafish embryos. Taken together, Se-Met-plays an important role in preventing toxic damage induced by fluoride in zebrafish embryos, although it has certain toxic effects.

Attenuating Effect of Vitamin E against Silver Nano Particles Toxicity in Submandibular Salivary Glands

Silver nanoparticles (AgNPs) are extensively used in many industries due to their superior antimicrobial properties. However, it is evident from many studies that AgNPs has cytotoxic potential through its effect on excessive formation of reactive oxygen species (ROS). The aim of this study was to examine the toxic effect of AgNPs on the submandibular salivary glands and the attenuating effect of vitamin E, as a natural antioxidant, against this toxicity. Thirty Albino rats were divided into 3 groups (n = 10): control group, AgNPs group receiving 2 mg/kg daily for 28 days, and AgNPs and vitamin E group receiving AgNPs the same as the previous group in addition to vitamin E at a dose of 100 mg/kg. Microscopic, ultrastructural, and cytokeratin immune-reactivity examination of the glands were performed. The AgNPs group showed noticeable degeneration in all structures of the gland as evident in the histological and ultrastructural examination. The AgNPs and vitamin E group revealed an improvement of the glandular elements. A significant increase in cytokeratin immune expression was found after comparison of both groups (p = 0.01). This current study shows that vitamin E has powerful antioxidant properties, which can combat the cytotoxic effect caused by AgNPs. Further studies are deemed necessary to confirm this finding using other immunohistochemical markers, such as myosin and E-cadherin.

Synthesis, characterization & evaluation of venom neutralization potential of silver nanoparticles mediated Alstonia scholaris Linn bark extract

Objective

The venom neutralization potential of silver nanoparticle(AgNP-AS) mediated bark extract of Alstonia scholaris Linn R.Br was investigated in the study.

Methods & materials

AgNP-AS was synthesized with respect to optimal temperature, pH of extract. UV-vis, FT-IR, XRD, TEM, SEM studies were used to characterize silver nanoparticles of Alstonia scholaris Linn(AgNP-AS). The potential of AgNP-AS in neutralization of venom lethality, rise in myotoxicity markers(LDH) and proinflammatory cytokines(IL6, TNFα) were evaluated in animal models.

Results

AgNP-AS was synthesized optimally with AgNO₃ (2 mM); extract concentration, 0.2 gm/l (1% w/v); extract (pH 9) and optimal temperature (40 °C). The colour change and synthesis of AgNP-AS was validated by UV-vis analysis at 432 nm. Transmission electron microscopy of AgNP-AS showed that the particle size for AgNP-AS was 14 nm-20 nm. FT-IR revealed peaks at 3445 cm^-1, 1646 cm^-1, 1346 cm^-1 and 1108 cm^-1. From the dynamic light scattering studies the hydrodynamic diameter (115.87 nm) and zeta potential(-29.8 mV) were estimated. The EDAX exhibited a peak for silver validating that the synthesized silver was pure. The biosynthesized (AgNP-AS) could significantly neutralize Viper russelli venom(VRV) induced rise in serum lactate dehydrogenase(LDH) and proinflammatory cytokines(IL6, TNFα) in animal models.

Conclusion

The culmination of nanotechnology with herbal medicine might endow with a really constructive tool in coming up with future drugs with fewer toxicity.

Genotoxicity, oxidative stress, and biochemical biomarkers of exposure to green synthesized cadmium nanoparticles in Oreochromis niloticus (L.)

The considerable increment in the use of Nanoparticles in the industry has been recognized as an environmental concern today. Therefore, this study aimed to investigate the toxicity effects of green synthesized cadmium nanoparticles [Cd]^NPs using Moringa oleifera leaves extract on multi-biomarkers in Oreochromis niloticus after four weeks of exposure. The results showed that LC₅₀ values of [Cd]^NPs for 24, 48, 72 and 96 h were 2.17, 1.75, 1.49 and 1.22 mg l^-1, respectively. There was a significant decrease in the number of white and red blood cells, hemoglobin, hematocrit, mean corpuscular hemoglobin concentration value in fish exposed to [Cd]^NPs. The mean corpuscular volume and neutrophils were increased. [Cd]^NPs exposure to fish has led to cytotoxic and genotoxic changes in the erythrocytes. Significant changes were observed in the cortisol, triiodothyronine, and thyroxine levels of the fish exposed to [Cd]^NPs. The activities of aspartate aminotransferase and alanine aminotransferase increased. Glucose, total lipids, urea, and creatinine levels increased in the serum of fish exposed to [Cd]^NPs, whereas total protein contents and alkaline phosphatase activity decreased. A significant reduction was observed in glycogen, total antioxidant levels, and superoxide dismutase, catalase and glutathione S-transferase activities of fish exposed to [Cd]^NPs. In contrast, the [Cd]NPs exposure resulted in a significant increase in DNA fragmentation percentages, lipid peroxidation, and carbonyl protein levels in different tissues. The results of the present study confirmed that [Cd]^NPs has the toxicity potential to cause Cyto-genotoxicity, oxidative damages, changes in the hematological and biochemical changes, and endocrine disruptor in the fish.

Amelioration of diethylnitrosamine (DEN) induced renal oxidative stress and inflammation by Carissa carandas embedded silver nanoparticles in rodents

•

Phytofabricated silver nanoparticles (CCAgNPs) were biosynthesized and characterized.

•

CCAgNPs were evaluated against diethylnitrosamine induced renal cancer.

•

Silver nanoparticles have an antioxidant property.

•

Silver nanoparticles unveiled a therapeutic effect against renal cancer in vivo.

Introduction

Inflammation and oxidative stress are the main factors ascribed with interruption in the process of renal tissue impairment. The toxicity of different types of nitrosamine is well recognized in animals and humans. Administration of the smallest quantities of diethylnitrosamine or dimethylnitrosamine either orally or parenterally results into renal damage. Therapeutic effects of phytofabricated silver nanoparticles of Carissa carandas aqueous extract has been scrutinised in current study for the assessment of renal cancer activity in animal model.

Methodology

Phytofabricated silver nanoparticles were characterized by using different instrumentation. Nephroprotective activity of silver nanoparticles at different doses was evaluated against N-diethylnitrosamine (200 mg/kg b.w., intraperitoneal) in animal model. Serum and renal homogenate were taken to evaluate the renal toxicity markers, oxidative stress, and antioxidant parameter, proinflammatory cytokines and histopathological study.

Result

Significant outcomes of silver nanoparticles in dose dependent manner down regulated the elevated serum marker, tumour marker enzymes and histopathology observation of repaired tissue assured the renal cancer activity in animals. In addition, profile of enzymatic and non-enzymatic antioxidant, proinflammatory cytokines and tumour promotion marker also favours the anticancer property of silver nanoparticles.

Conclusion

The data of current study reveals silver nanoparticles ameliorates renal oxidative stress and carcinogenesis which was induced by N-diethylnitrosamine and accredited to antioxidant and anticancer activities of phytofabricated nanoparticles by biological approach.

Does the adsorbent capacity of orange and banana peels toward silver nanoparticles improve the biochemical status of Oreochromis niloticus?

Silver nanoparticles (Ag NPs) have wide medical and industrial applications; therefore, their release into aquatic environments is a problematic issue. The present study aims to evaluate the removal efficiency of Ag NPs from water using orange peel (OP) and banana peel (BP) to moderate their toxicity on Oreochromis niloticus. Fish were divided into 4 groups: control group (dechlorinated tap water), Ag NPs (4 mg/L) exposed group, Ag NPs (4 mg/L) + OP (40 mg/L) group, and Ag NPs (4 mg/L) + BP (40 mg/L) group for 24 h, 48 h, and 96 h. The adsorptive ability of both peels was confirmed by scanning electron microscope and energy-dispersive X-ray spectroscopy after the exposure processes. The biochemical results revealed a gradual elevation in plasma glucose, total proteins, globulin, liver enzymes (AST, ALT, and ALP), creatinine, and uric acid after Ag NPs exposure, while albumin and total lipid concentrations were significantly decreased. The recorded antioxidant biomarkers in gills, and liver tissues after Ag NPs exposure showed severe oxidative damages (maximally after 96 h) as indicated by marked elevations in thiobarbituric acid reactive substances, glutathione peroxidase, catalase, and superoxide dismutase values, and decreased glutathione reduced content. All studied parameters restored more or less to that of control groups after OP and BP water treatment. The adsorbent abilities of both peels could reduce Ag NPs bioavailability and moderate their toxicological impacts.

The biodistribution of melanomacrophages and reactivity of PEG or amine-functionalized iron oxide nanoclusters in the liver and spleen of Egyptian toad after intraperitoneal or oral injections: Histochemical study

Recently, toad flesh is the main source of protein for many peoples. Of note, disease treatment of amphibian animals is a big challenge facing toad farms development. Iron oxide nanoclusters (IONCs) are approved by the Food and Drug Administration (FDA) as new materials for drug delivery systems development. The biodistribution and fate of IONCs in the lower vertebrate tissues such as toads is novel and should be studied in details. In this study, the biodistribution and toxicities of polyethylene glycol-functionalized IONCs (PEG-IONCs) and amine-functionalized IONCs (NH₂-IONCs) in the liver and spleen of Egyptian toad were studied after intraperitoneal or oral injections. The localization and levels of IONCs in liver and spleen depends on the root of injection and the surface functionalization. The presence of IONCs in the liver and spleen produced sever to mild histological and histochemical abnormalities, but in a different ratio. The change of melanomacrophages (MMs) numbers depends on the root of injection or the function group on the surface of IONCs and this explains the abnormalities of MMs produced by IONCs treatment. Further, the function group on the surface may control the biodistribution of MMs and abnormalities produced by IONCs in the liver and spleen. Understanding the biodistribution and histological abnormalities of IONCs in the lower vertebrate tissues (amphibians in this study) might introduce important information to develop new drugs which can be used for amphibian diseases treatment or diagnosis. Further, the histopathological and MMs abnormalities produced by IONCs may consider as biomarkers for amphibians diseases diagnosis.