Article

Histopathological effects of waterborne copper nanoparticles and copper sulphate on the organs of rainbow trout (Oncorhynchus mykiss)

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Abstract

It is unclear whether copper nanoparticles are more toxic than traditional forms of dissolved copper. This study aimed to describe the pathologies in gill, gut, liver, kidney, brain and muscle of juvenile rainbow trout, Oncorhynchus mykiss, exposed in triplicate to either a control (no added Cu), 20 or 100μgl(-1) of either dissolved Cu (as CuSO(4)) or Cu-NPs (mean primary particle size of 87±27nm) in a semi-static waterborne exposure regime. Fish were sampled at days 0, 4, and 10 for histology. All treatments caused organ injuries, and the kinds of pathologies observed with Cu-NPs were broadly of the same type as CuSO(4) including: hyperplasia, aneurisms, and necrosis in the secondary lamellae of the gills; swelling of goblet cells, necrosis in the mucosa layer and vacuole formation in the gut; hepatitis-like injury and cells with pyknotic nuclei in the liver; damage to the epithelium of some renal tubules and increased Bowman's space in the kidney. In the brain, some mild changes were observed in the nerve cell bodies in the telencephalon, alteration in the thickness of the mesencephalon layers, and enlargement of blood vessel on the ventral surface of the cerebellum. Changes in the proportional area of muscle fibres were observed in skeletal muscle. Overall the data showed that pathology from CuSO(4) and Cu-NPs were of similar types, but there were some material-type effects in the severity or incidence of injuries with Cu-NPs causing more injury in the intestine, liver and brain than the equivalent concentration of CuSO(4) by the end of the experiment, but in the gill and muscle CuSO(4) caused more pathology.

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November 2012
Genan Al-bairuty · Theodore B Henry · Ben Shaw · Richard D Handy
... Moreover, our findings were also consistent with those reported in the gill tissues of guppies exposed to CuONPs for 10 days [26]. Al-Bairuty et al. [23] illustrated that exposure to CuONPs resulted in edema, hyperplasia, lamellar fusions, clubbed tips, aneurisms, and necrotic changes in the secondary gill lamellae of rainbow trout. Moreover, edema of the gill epithelium, hyperplasia at the base of the secondary gill lamellae, clubbed tips, lamellar fusion, occasional aneurism, and swelling in the secondary lamellae were evident in common carp exposed to CuONPs [29]. ...
... Hyperplasia leads to lamellar fusion, which will counteract the gaseous exchange mechanisms, negatively affect the oxygen uptake by the gill tissues, and subsequently increased the partial pressure of carbon dioxide leading to metabolic and respiratory acidosis [75]. The evidence of gill edema may be closely linked to the toxic effects of NPs in the inhibition of ionic transport across the gill epithelium by the branchial Na + /K + ATPase, which will, in turn, leads to disruption of the osmotic regulation and then osmotic imbalance occurs [23,76]. Collectively, the exposure to CuONPs might induce osmoregulatory failure, negatively affect the countercurrent gaseous exchange mechanisms, and decrease the uptake of dissolved oxygen from the water, which will subsequently lead to asphyxiation, respiratory failure, and death [77,78]. ...
... Previous reports illuminated that fish exposed to CuONPs demonstrated hepatic damage [80]. Al-Bairuty et al. [23] reported necrosis, small foci of hepatitis-like injury, pyknotic nuclei, and an increased number of melanomacrophage deposits in CuONPs-exposed common carp. Moreover, Gupta et al. [29] reported a pronounced increased number of pyknotic nuclei, vacuolations, and necrotic changes in hepatopancreatic tissues of common carp exposed to CuONPs. ...
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In the present study, fish were exposed to sub-lethal doses of CuONPs (68.92 ± 3.49 nm) (10 mg/L, 20 mg/L, and 50 mg/L) for a long exposure period (25 days). Compared to the control group (0.0 mg/L CuONPs), a significant dose-dependent elevation in blood urea and creatinine values, serum alanine transaminase, aspartate transaminase, and alkaline phosphatase enzyme activities were evident in CuONPs-exposed groups (p < 0.05). Fish exposure to 50 mg/L CuONPs significantly upregulated the transcription of pro-inflammatory cytokines (tumor necrosis factor-alpha, interleukin-1beta, interleukin 12, and interleukin 8), heat shock protein 70, apoptosis-related gene (caspase 3), and oxidative stress-related (superoxide dismutase, catalase, and glutathione peroxidase) genes in liver and gills of the exposed fish in comparison with those in the control group (p < 0.05). Moreover, varying histopathological injuries were noticed in the hepatopancreatic tissues, posterior kidneys, and gills of fish groups correlated to the tested exposure dose of CuONPs. In summary, our results provide new insights and helpful information for better understanding the mechanisms of CuONPs toxicity in Nile tilapia at hematological, molecular levels, and tissue levels.
... However, after being in the clean water for 14 days, the livers of the fish still contained high levels of copper, with no reverse actions that took place. This suggests the need for more studies on the late stages of toxicity [95,96]. In another study, the effects of copper on the liver enzymes hexokinase, phosphofructokinase, pyruvate kinase, lactate dehydrogenase, and glycose-6-phosphate dehydrogenase in Prochilodus lineatus demonstrated the different effects of copper in relationship with temperature for all the mentioned enzymes [97]. ...
... To analyze the toxicity of copper nanoparticles (CuNPs) over traditionally dissolved copper, O. mykiss fish were exposed to CuNPs. This led to hepatitis-like injuries and cells with pyknotic nuclei in the liver [96]. ...
Article
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This review summarizes the present knowledge on the toxicity of copper and copper nanoparticles (CuNPs) to various fish species. In previous decades, the excessive usage of metal and metallic nanoparticles has increased significantly, increasing the probability of the accumulation and discharge of metals in various trophic levels of the environment. Due to these concerns, it is important to understand the toxicity mechanisms of metals and metallic nanoparticles before they lead to unhealthy effects on human health. In this review paper, we specifically focus on the effect of metal copper and CuNPs on different fish organs under different physiochemical parameters of various water bodies. Nowadays, different forms of copper have distinctive and specific usages, e.g., copper sulfate is a well-established pesticide which is used to control the growth of algae in lakes and ponds. Deactivating the fungi enzymes prevents fungal spores from germinating. This process of deactivation is achieved via the free cupric ions, which are established as the most toxic forms of copper. Complexes of copper with other ligands may or may not be bioavailable for use in aquatic organisms. On the other hand, CuNPs have shown cost-effectiveness and numerous promising uses, but the toxicity and availability of copper in a nanoparticle form is largely unknown, Additionally, physiochemical factors such as the hardness of the water, alkalinity, presence of inorganic and organic ligands, levels of pH, and temperature in various different water bodies affect the toxicity caused by copper and CuNPs. However, comprehensive knowledge and data regarding the pattern of toxicity for copper metal ions and CuNPs in marine organisms is still limited. In this review, we carry out a critical analysis of the availability of the toxicological profiles of copper metal ions and CuNPs for different fishes in order to understand the toxicity mechanisms of copper and CuNPs. We believe that this review will provide valuable information on the toxicological profile of copper, which will further help in devising safe guidelines for the usage of copper and CuNPs in a sustainable manner.
... Similar observations were also noted in Nile tilapia exposed to Cd (Mahrous et al., 2015) and C. carpio exposed to Cu (Malekpouri et al., 2016). The main accumulation organ for Cu is the liver (Al-Bairuty et al., 2013), and thus in the present study Cu may not have shown pronounced effects on gill and kidney tissues. ...
... Although GN was not so pronounced in 0.05 mg/L and 0.2 mg/L groups, 0.8 mg/L and 3.2 mg/ L groups showed a markable change (Fig. 3). Such alterations, including degeneration of Bowman's capsules, GN, and reduction in tubular lumens of kidney, were also apparent in Channa punctatus exposed to Cr (Mishra and Mohanty, 2008), Nile tilapia to Cd (Mahrous et al., 2015), and Rainbow trout to Cu (Al-Bairuty et al., 2013). The damages were more prominent on day 28 in 0.05 mg/ L group (Fig. 3b), while that for 0.2 mg/L group were distinct on 14 days of exposure (Fig. 3c). ...
Article
Heavy metals (HMs) in an aquatic environment mainly affects fish, and thus, fish are convenient pollution bio-indicators. In this study, the toxic effects of HM mixture (chromium (Cr), cadmium (Cd), copper (Cu)) in 0 mg/L to 3.2 mg/L concentration range was investigated in Cyprinus carpio (28 days). HM accumulation, histopathology, oxidative stress, and gut microbial changes were evaluated. HMs accumulated in the order of Cr > Cu > Cd, primarily in the kidneys and finally scales. Reactive oxygen species generation increased in all exposure groups upto day 14, with maximum generation at 3.2 mg/L mixture, which later decreased on day 28 in all. Malondialdehydeand and superoxide dismutase levels increased from day 7 to 28 with increased HM concentrations, while total protein showed an inverse trend. Gill histopathology showed major changes such as uplifted and disintegrated primary lamella, and secondary lamella shortening. The kidneys were characterized by glomerular necrosis, Bowman’s capsule expansion, and tubular space dilatation. Proteobacteria and Firmicutes abundance increased upto 59.4% and 99.16% in 0.8 mg/L and 3.2 mg/L treatment groups, respectively. This study provided a better understanding on the physiology and gut microbiota alteration in C. carpio under multiple HM stress.
... These observations suggest that excess of heavy metals caused histological alterations mainly via generations of reactive oxygen species 38 . Hepato-cellular damage, caused by heavy metal overloads has also been reported earlier in other fish species 24,39 . Kidney sections of the reference group shown in Fig. 1c, showed a normal structure such as glomeruli, bowman's space with uniform kidney tubules. ...
... However, the major hallmarks that were observed in exposed fish tissue were decreased or no bowman's space, large vacuolation, necrosis, damaged tubule and glomeruli, and leucocyte infiltrations (Fig. 1d). Several other studies also reported the abnormalities in kidney structure in other fishes due to the exposure of metal contaminated water in the form of reduction of renal hematopoietic system, tissue damage, necrosis, glomerular injury, proliferation of connective tissue, glomerular and epithelial tubuli contraction 39,40 . ...
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The current study was carried out on dominant fish Oreochromis niloticus and water collected from the polluted Yamuna River, Agra, India. The heavy metals in water, recorded as follows: Fe > Mn > Zn > Cu > Ni > Cr > Cd and all were found to be above the prescribed limits. According to metal pollution index, exposed muscle (49.86), kidney (47.68) and liver (45.26) have been recorded to have higher bioaccumulation. The blood biochemical analysis of exposed O. niloticus indicated significant increase in activities of aspartate aminotransferase (+ 343.5%), alkaline phosphatase (+ 673.6%), alanine aminotransferase (+ 309.1%), and creatinine (+ 494.3%) over the reference. However, a significant decrease in albumin (A): globulins (G) ratio (- 87.86%) was observed. Similarly, the exposed fish also showed significant increase in total leucocyte count (+ 121%), differential leucocyte count, respiratory burst (+ 1175%), and nitric oxide synthase (+ 420%). The histological examination of liver and kidney showed tissue injury. Moreover, micronuclei (0.95%), kidney shaped nuclei (1.2%), and lobed nuclei (0.6%) along with DNA damage in the form of mean tail length in the liver (20.7 µm) and kidney (16.5 µm) was observed in the exposed O. niloticus. Potential health risk assessments based on estimated daily intake, target hazard quotient, hazard index, and target cancer risk indicated health risks associated with the consumption of these contaminated fishes. In conclusion, the present study showed that exposure to heavy metals contaminated water can alter immunological response; induce histopathological alterations and DNA damage in the studied fish. The consumption of this contaminated water or fish could have serious impact on human health.
... There was some detectable Cu in the View Article Online aquarium water, but this was at a trace level (<3 μg l −1 ), and the total Cu concentrations in the gill remained low (Table 1). There was also no evidence of pathology in the gills, which is typically associated with waterborne CuSO 4 or Cu ENM exposures (e.g., Al-Bairuty et al. 28 ). Taken together, these observations confirm dietary, rather than waterborne, exposure in the present study. ...
... The elevated total Cu might arise from melanomacrophage activity trapping particulate Cu in the parenchyma as observed in aqueous exposures to Cu ENMs in trout. 28 However, Cu excretion via the urine is usually minimal in trout, with the liver being the main excretory organ, 30 and (Table 2), it suggests that renal function was not lost. However, any bioaccumulation hazard might be transient since the intestines and the carcass showed decreases in total Cu concentrations back to control levels in the post-exposure phase (Table 1), in keeping with dissolved Cu being an essential nutrient that is homeostatically controlled. ...
Article
The dietary bioaccumulation potential of engineered nanomaterials (ENMs) remains poorly understood. The aim of the current study was to assess the dietary bioaccumulation of copper from copper oxide (CuO) ENMs...
... Kidneys are an important excretory and osmoregulatory organ in fish and play an important role in maintaining the water-salt balance (Marshall and Grosell, 2006). The tissue alterations observed in the present study are consistent with similar pathological responses reported in previous studies, also in trout, using different chemical compounds, including NPs (Federici et al., 2007;Al-Bairuty et al., 2013;Rodrigues et al., 2017;Correia et al., 2019). ...
... In general, changes in the gills typically lead to respiratory failure, hypoxia and ionic and acid-base imbalances (Alazemi et al., 1996;Yasser and Naser, 2011). Although significant differences were recorded in fish exposed to CeO2 NPs these alterations are non-specific and can occur after the exposure of fish to several xenobiotics (Nero et al., 2006;Al-Bairuty et al., 2013;Rodrigues et al., 2017Rodrigues et al., , 2019. All these reported tissue damages altered the various pathological indices for gills, and also some morphometric measurements, but no changes were recorded in PAGE index, suggesting that at least the respiratory function was unaffected. ...
Article
Cerium oxide nanoparticles (CeO2-NP) have already been detected in the aquatic compartment, however, the evaluation of potential ecotoxicological effects on biota are scarce. The present study aimed to assess the toxic effects of CeO2-NP in Oncorhynchus mykiss in different organs/tissues (gills, liver and kidney) after acute exposure (96h) at three concentrations: 0.25, 2.5 and 25 mg/L. Oxidative stress response (Catalase - CAT; Glutathione S-Transferases - GSTs), lipid peroxidation (Thiobarbituric Acid Reactive Substances - TBARS), Na+/K+-ATPase activity, genotoxicity (genetic damage index - GDI) and histopathology (organ’s pathological indices) were evaluated. CAT activity was increased in gills and decreased in liver of fish exposed to the highest CeO2–NPs concentration tested. However, GSTs and Na+/K+-ATPase activities and TBARS levels were not significantly altered in analysed organs. CeO2–NP caused marked changes in the gills (aneurysms, blood capillary congestion, lamellar hypertrophy and hyperplasia, secondary lamella fusion and epithelial lifting), in liver (pyknotic nucleus, hyperemia, enlargement of sinusoids and leucocyte infiltration) and kidney (shrinkage of the glomeruli, enlargement of the Bowman space, tubular degeneration and nuclear hypertrophy). Moreover, a semiquantitative histopathological scoring system (pathological index) confirmed significant alterations in the three organs of all exposed fish. Furthermore, a significant increase of GDI indices observed in gills and liver, for all tested concentrations, indicated a dosedependent effect. The present study suggest that the release of CeO2-NP into the aquatic environment promotes biochemical, genotoxic and histopathological damages in fish. However, the mechanisms underlying the occurrence of such effects require further investigation.
... The immature red cells and hypochromia frequently observed at was corroborated with the study on the effects of pollution on Gobius niger [55]. In Oreochromis niloticus exposed to lead, the percentage of immature erythrocyte count and binuclear erythrocytes were found to increase [56]. Similarly the exposure of fish to ultra-violet radiation (320-400 nm) resulted micronuclei and binuclear erythrocytes were found in Clarias gariepinus [57]. ...
... Although no physiological significance is attributed to silver, it can be accumulated in organisms after its application. The toxicity of silver to rainbow trout was demonstrated by Al.-Bairuti et al. [26], who observed an increase in silver content in the eggs, depending on silver concentration; similar tendencies were noted by Morgan and Wood [27]. In our study, the levels of silver accumulation were also dependent on the type of chemical compound used. ...
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Nanotechnology is a rapidly growing field of science, and an increasing number of nanoproducts, including nanometals, can be found on the market. Various nanometals and the products that are manufactured based on them can help to fight bacteria and fungi, but they can also penetrate organisms and accumulate in them. This study aimed to compare the effects of two metals, silver (Ag) and copper (Cu), with known antibacterial and fungicidal properties in their ionic (AgNO3, CuSO4·5H2O) and nanoparticle (AgNPs, CuNPs) forms on rainbow trout eggs and fry. Concentrations of metals ranging from 0 to 16 mg/L were used during egg swelling for 2 h. The swelling of eggs in Cu solutions resulted in an increase in Cu content in the eggs (just like in the case of Ag); however, the changes in fry were not significant in the case of both Ag and Cu. The concentrations of these metals in eggs was greatly affected by the applied form of Ag and Cu. Because CuNPs penetrated the embryo in fish eggs at lower concentrations compared to AgNPs, it would be worth considering them for antibacterial applications during egg incubation.
... The lifting is because of edema (Schwaiger et al. 2004). Another reason of lifting of the lamellar epithelium may be due to collapse of pillar cells that damages the vascular integrity with the release of a large amount of blood pushing the lamellar epithelium outward and making the secondary epithelium separated (Alazemi et al. 1996), while swelling (edema) or lifting could be also due to the decline in blood sodium and chloride concentration or decrease in the gill sodium-and potassiumactivated ATPase (Nieboer and Richardson 1980) resulting in the osmotic imbalance and inhibits the entry of toxins (Al-Bairuty et al. 2013). In the present investigation, defense response was also observed in the form of epithelium uplifting and fusion of the primary and secondary lamellae as reported by various investigators (Van Heerden et al. 2004). ...
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Paraquat dichloride is a broad-spectrum herbicide used worldwide. It is very fast acting and used to kill a wide range of grasses and broad-leaved weeds. Paraquat dichloride gets run off to aquatic water bodies, and its presence has been reported by various researchers, where its effect is certain on aquatic organisms. Fish are vulnerable to aquatic pollutants as they are in direct contact with their environment. Therefore, our study was designed to evaluate the effects of herbicide paraquat dichloride on histology of vital organs (gills, liver, and kidney) of the fresh water fish Channa punctatus (Bloch). Toxicity effects are evaluated under static renewal test conditions, and histological alterations were detected microscopically. Fish were exposed to acute dose (96hLC50/2 = 32.93 mg/L) for 96 h of paraquat dichloride. Simultaneous control was also maintained. Principal histopathological alterations in gills during acute exposure showed curling of secondary lamellae, aneurysm, gill bridging, and enlargement of the cartilaginous core. The tissue damages like melanomacrophage centers, pyknotic nucleus, large sinusoidal congestion, and cell fusion are some histological alterations observed in the liver after acute exposure. The changes in histoarchitecture observed in the kidney include an increase in Bowman’s space, necrosis of glomeruli, and damage to collecting duct at acute exposure. The histopathological changes were more prominent with the duration of exposure in the experimental groups. The present study demonstrated that the vital organs exhibited significant damage, among all gill histology specifically got altered being directly exposed to paraquat dichloride. Paraquat dichloride exposure affects the histology of gills, liver, and kidney, thus impairing the vital functions like respiration, excretion, and metabolic regulation which in turn will affect the fish health and is a serious threat. Histopathological alteration in gills, liver, and kidney can be regarded as sensitive biomarkers of paraquat dichloride toxicological manifestations and thus can be utilized for ecotoxicological biomonitoring of aquatic bodies. Graphical abstract
... The state-of-the-art method is the impregnation of nets with coppercontaining antifouling paints that produce toxic surroundings near the surface to repel or kill potential biofouling organisms. This leads to large annual emissions of copper compounds that can exert a negative impact on the farmed stock and the surrounding ecosystem (Al-Bairuty et al., 2013;Braithwaite and McEvoy, 2004;Burridge et al., 2010;Farkas and Skarbøvik, 2020;Simpson et al., 2013;Skarbøvik et al., 2017). Besides being environmentally hazardous, copper-containing coatings commonly used in the aquaculture industry exhibit limited efficiency against biofouling and are not able to prevent biofouling for the entire production cycle (Bloecher et al., 2015;Guenther et al., 2010). ...
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This study demonstrates a robust, flexible interpenetrated composite based on 3D spined fabrics as core material and polydimethylsiloxane (PDMS) as shell material. The penetration of the shell component into the core material enables the mechanical interlocking at the micro and macro scale, providing mechanical stability and at the same time, introducing hydrophobic surface properties. Pure PDMS is a well-known biofouling-release material, showing drawbacks with respect to mechanical strength and adhesion-to-substrate, which can be overcome by the presented approach. Nowadays, antifouling strategies for aquaculture nets are realized by using biocide-containing coatings to avoid the attachment of organisms or repel them. Up to now, there are no coatings available on the market that provide adequate biofouling protection for aquaculture nets during the whole production cycle of the cultured stock. Even biocidal coatings exhibit a limited efficiency and need to be regularly cleaned, causing a substantial loss of the coating and increased emissions of biocides into seawater. This proof-of-concept study covers the scope from the design and production of the composite up to the first field tests in the Baltic Sea. The presented approach enabled by material science facilitates a fundamentally different approach in biofouling management and contributes to sustainable aquaculture.
... Cu-nanoparticles were found to be extremely lethal to adult zebrafish, where their gills were the main target during acute exposure, experiencing severe damage (Griffitt et al., 2007). In addition, Cu has already been found to trigger oxidative stress (Doria et al., 2018), causing DNA damage in the gill and liver tissues (Turan et al., 2020) and lesions in the gills (Al-Bairuty et al., 2013;Luzio et al., 2013;Song et al., 2015). This may cause pain (Jiraungkoorskul et al., 2002) and osmoregulation disorders depending on the function of the gills (Evans, 1987;Evans et al., 2005;Guh et al., 2015). ...
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... In ecotoxicology studies it is still common practice to limit histopathological and quantitative morphological gill analyses to samples taken from arbitrarily chosen locations and histological (paraffin-) sections with determined orientations, using semiquantitative scoring systems or simple 2-D morphometric analysis techniques [22, [126][127][128]. However, such analysis approaches are inherently not capable to provide unbiased quantitative morphological data [14,25,70,129]. ...
Article
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Rainbow trout ( Oncorhynchus mykiss ) are frequently used as experimental animals in ecotoxicological studies, in which they are experimentally exposed to defined concentrations of test substances, such as heavy metals, pesticides, or pharmaceuticals. Following exposure to a broad variety of aquatic pollutants, early morphologically detectable toxic effects often manifest in alterations of the gills. Suitable methods for an accurate and unbiased quantitative characterization of the type and the extent of morphological gill alterations are therefore essential prerequisites for recognition, objective evaluation and comparison of the severity of gill lesions. The aim of the present guidelines is to provide practicable, standardized and detailed protocols for the application of unbiased quantitative stereological analyses of relevant morphological parameters of the gills of rainbow trout. These gill parameters inter alia include the total volume of the primary and secondary gill lamellae, the surface area of the secondary gill lamellae epithelium ( i . e ., the respiratory surface) and the thickness of the diffusion barrier. The featured protocols are adapted to fish of frequently used body size classes (300–2000 g). They include well-established, conventional sampling methods, probes and test systems for unbiased quantitative stereological analyses of light- and electron microscopic 2-D gill sections, as well as the application of modern 3-D light sheet fluorescence microscopy (LSFM) of optically cleared gill samples as an innovative, fast and efficient quantitative morphological analysis approach. The methods shown here provide a basis for standardized and representative state-of-the-art quantitative morphological analyses of trout gills, ensuring the unbiasedness and reproducibility, as well as the intra- and inter-study comparability of analyses results. Their broad implementation will therefore significantly contribute to the reliable identification of no observed effect concentration (NOEC) limits in ecotoxicological studies and, moreover, to limit the number of experimental animals by reduction of unnecessary repetition of experiments.
... Nanoparticles, because of their physical and chemical characteristics such as smaller size and greater specific surface area react faster than the bigger mass particles, hence their usage in industry accelerated greatly since their first usage in 2000s (Al-Bairuty et al. 2013). This increase, however, resulted in their excessive release to the environment, imposing a big threat to the organisms living there. ...
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Impacts of titanium dioxide nanoparticles (TiO2 NPs) on serum glucose, albumin, total protein, cholesterol, triglyceride, sodium (Na+), potassium (K+), and chloride ion (Cl−) levels and serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH) and cholinesterase (ChE) activities of Clarias gariepinus were determined after exposing the fish to 1, 5 and 10 mg/L titanium applied as TiO2 over 1, 4 and 7 days. No mortality was observed during the experiments. Serum glucose and albumin levels increased while serum total protein, cholesterol and triglyceride levels decreased compared to control at the end of the 7th day. Serum Na+, K+ and Cl− levels of C. gariepinus decreased after 7 days of exposure to 10 mg/L TiO2 NPs. ChE activity decreased and AST, ALT, ALP activities increased at all exposure concentrations and LDH activities increased compared to control after 4 and 7 days of exposure to TiO2 NPs in C. gariepinus.
... and haemolymph channels and juncture of adjacent lamellae have been reported in prior studies. Exposure to copper nanoparticles in rainbow trout led to oedema, junction of adjacent gill lamellae, clubbed shape of gill filaments, hyperplasia and necrosis of gill lamellae (Al-Bairuty et al. 2013). Exposure to colloidal copper nanoparticles caused epithelial cell proliferation as well as oedema in gill filaments in zebrafish (Griffitt et al. 2007). ...
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The original version of this article unfortunately contained a typo in university name in second affiliation. The correct affiliation is Department of Aquatic Production and Exploitation, Faculty of Fisheries and Environmental Sciences, Gorgan University of Agricultural Sciences and Natural Resource, Gorgan, Iran
... We also observed histopathological changes, such as the dissolution of renal tubules and glomerular shrinkage, in the kidneys of CuSO 4 -exposed fish, whereas only mild degeneration of renal tubules was found in the kidneys of fish exposed to CuO-NPs. This is also consistent with the results of previous studies (Abdel-Khalek et al. 2015;Al-Bairuty et al. 2013;Handy 2003;Kosai et al. 2009), which have reported similar pathologic changes including renal epithelial degeneration and necrosis, shrinking of the glomerulus, alterations in Bowman's space, and melanomacrophage proliferation. Overall, however, we found that exposed fish pre-fed the basal diet supplemented with Spirulina showed markedly fewer histopathological alterations than those in the nonsupplemented copper-exposed groups. ...
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Copper has toxic effects in fish, whereas the cyanobacterium Spirulina reportedly has protective effects against metal toxicity in various animal species. The current study, therefore, aimed to investigate the prophylactic role of Spirulina platensis against the effects of copper sulfate (CuSO4) and copper oxide nanoparticles (CuO-NPs) in Nile tilapia (Oreochromis niloticus). Biochemical, antioxidant, erthyron profile and histopathological endpoints were assessed after for 15 days of exposure in five separate treatment groups: (1) fish pre-fed the normal diet (control), (2) fish pre-fed the normal diet and exposed to 15 mg/L of CuSO4, (3) fish pre-fed the normal diet augmented with 0.25% Spirulina and exposed to 15 mg/L of CuSO4, (4) fish pre-fed the normal diet and exposed to 15 mg/L of CuO-NPs, and (5) fish pre-fed the normal diet augmented with 0.25% Spirulina and exposed to 15 mg/L CuO-NPs. Exposure to CuSO4 or CuO-NPs significantly increased superoxide dismutase and catalase activities in fish, as well as serum total protein, glucose, aspartate aminotransferase, alanine aminotransferase, creatinine, and uric acid concentrations. In contrast, most hematological indices in fish significantly decreased after CuSO4 or CuO-NPs exposure. Moreover, CuSO4 and CuO-NPs caused a significant increase in the percentage of poikilocytosis and nuclear abnormalities of red blood cells, as well as histopathological changes in the brain, liver, intestine, and kidneys. Importantly, Spirulina supplementation mitigated against physiological disruption caused by CuSO4 or CuO-NPs. Graphical abstract
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... In the present study, neuronal cell necrosis and vacuolization were observed after CPF and IDC exposure at 96 hours. This study is in agreement with other findings that reported mild necrosis and vacuolar changes of the fish brain of Channa punctatus after exposure of endosulfan at 96 hours [38], pycnosis, karyorrhexis, and karyolysis in the neuronal cells of the telencephalon, other lobes of common carp exposed to cypermethrin [39], and occasional necrosis and vacuolization of neuronal cells of telencephalon after exposure of Copper sulfate [40]. ...
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The current study is an attempt to compare the potential effects of acute exposure of two widely used insecticides, chlorpyrifos (CPF) and indoxacarb (IDC), on the histopathology of fish brain and its impact on locomotory behavior of a catfish, Heteropneustes fossilis, as a non-target species. In our study, fishes of lentic habitats (n = 12/group) were exposed to LC 50 doses of CPF (1.92 mg/l) and IDC (0.075 mg/l) for 96 hours. During the experiment, locomotory activities of control and exposed fishes (n = 6/group) were recorded at a regular period by ANY-MAZE software (Stoelting Co., Chicago, IL). At the endpoint of 96 hours, fishes were sacrificed for the histopathological study of the telencephalon region of the brain. The CPF toxicity induced highly degenerative changes and vacuolization in the neuronal cells of dorsal pars medialis (dDm) of the telencephalon, and substantial disturbances in the swimming pattern of mobile and immobile episodes, rotational locomotory movements; whereas IDC induced mild pathological changes in the dDm of telencephalon of fish brain, and irregular locomotory behavior in H. fossilis when compared to the control group. Thus, the present study concludes that IDC was found to be less toxic than CPF. Hence, IDC could be an alternate choice of the CPF at equal concentrations.
... Furthermore, Griffitt et al. (2007) and Al-Bairuty et al. (2013) in fish and Ibrahim et al. (2015) in rats supported our findings of severe hepatocellular necrosis where they demonstrated that the liver of treated group with high dose showed focal area of hepatocellular necrosis infiltrated by mononuclear cells and polyploidy hepatocytes represented by hepatic cytokaryomegaly accompanied with Kupffer cell activations as well as apoptosis. Hyperplasia of biliary epithelium, formation of newly formed bile ductules in addition to periportal sporadic hepatic cell necrosis and apoptosis were clarified. ...
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Copper nanoparticles are widely utilized in a variety of applications, including metal catalysts, semiconductors, heat transfer fluids in machine tools, and even in antibacterial medications. Forty mature healthy Westar rats were utilized in the current investigation and grouped randomly into four groups (n = 10 rats/group). Group I (G1) was kept as a control group, but G2, G3, and G4 were intraperitoneally injected with CuO NPs with a dose (5 mg, 10 mg, 25 mg/kg body weight/day) respectively for 9 days. Rats were sacrificed; then, the livers and kidneys were dissected and subjected to histopathological and immunohistochemical examination. Our findings of G2 and G3 revealed mild to moderate degenerative changes within the hepatic parenchyma, moderate blood vessel congestions, glycogen depletion, hemosiderosis, and microvesicular steatosis (fatty changes within the hepatocytes). In addition, at the level of kidney, our examination clarified moderate degenerations of the renal corpuscles and renal tubules with moderate swelling and congestions of the glomerulus with moderate vacuolations in the renal tubules lining epithelium. On the other hand, increasing the dose of CuO NPs, the toxicity became more obvious, where the liver of G4 revealed severe necrosis of hepatocytes with completely disorganizations of the hepatic rays, loss of the hepatic architectures, severe steatosis, severe hemosiderosis, sinusoidal dilatations with congestions, as well as severe fibrous tissue proliferation with anti-inflammatory cell infiltrations specially around portal triad with hyperplasia of bile duct. Meanwhile in kidney, G4 clarified severe necrosis and atrophy of the renal corpuscles with severe damage of Bowman’s capsule leading to completely disorganization and loss of normal renal cortex architectures, severe congestion of the glomerulus, severe necrosis of the renal tubules with damage and sloughing for its lining epithelium, and severe hemorrhage between renal tubules. In addition, severe and diffuse caspase 3 immunoreactivity were observed within the hepatic and renal tissues of G4. The present investigation was concluded that the CuO NPs have a potential toxicological effect on the hepatic and renal tissues that may affect their functions.--
... MP spheres that were used in the present study had a diameter of approximately 30 mm, and MP spheres around this size are quite abundant in the environment (Mintenig et al., 2020). These particles are too large to be absorbed into or penetrate the intestinal wall, as seen for nanoparticles and micro-sized particles with a diameter of approximately 10 mm (Brown et al., 2001;Hussain et al., 2005;Moore, 2006;Rothen-Rutishauser et al., 2007;Browne et al., 2008;Cedervall et al., 2012;Al-Bairuty et al., 2013;Al-Jubory and Handy, 2013). In nature, herring larvae of the size used in this study will actively select and ingest live prey significantly larger than 30 mm in size. ...
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A tube-feeding model for administering microplastic (MP, Ø = 30 μm) spheres to fish larvae was employed to quantify the uptake of hydrophobic organic contaminants (HOCs) into the larval body through a single administration of MP. Polychlorinated biphenyl-153 (PCB-153) was used as a representative HOC that can be sorbed to MP in the sea. Atlantic herring (Clupea harengus) larvae (34–51 days post-hatching) were selected as the animal model. The herring larvae were tube-fed a single load of up to 200 polystyrene or polyethylene MP spheres spiked with ¹⁴C-labelled PCB-153, and the control larvae were tube-fed an isotonic solution without MP. At the time of sampling (24 h post feeding), some larvae had evacuated all MP spheres from the gut, while others still had MP remaining in the gut. In larvae with a significant number of MP spheres still present in the gut, whole-body scintillation counting (including the MP in the gut lumen) showed elevated levels of the tracer compared to those in the control fish larvae. For larvae in which all or almost all MP had been evacuated by the time of sampling, the tracer levels of the whole body were not significantly different compared to those for the control fish larvae. These data indicate that there was no significant transfer of PCB-153 from contaminated MP into fish larvae within a gut-transit time of <24 h. This study suggests that the vector role of MP in HOC uptake and absorption may be minor compared to that of other HOC uptake pathways.
... Hypoxia causes morphological damage, and individuals become more susceptible to infection and even death. However, fish may develop physiological adaptation mechanisms by gill remodeling or specific neuroendocrine feedback regulation, thereby allowing their longterm survival under hypoxia stress or encountering other environmental irritants (Nilsson et al. 2012;Al-Bairuty et al. 2013;Liebel et al. 2013). The gill morphological changes that occur in response to hypoxia have been reported in several fish species, including goldfish (Perry et al. 2012), tropical reef fishes (Bowden et al. 2014), and crucian carp (Sollid et al. 2005). ...
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Hypoxia has gradually become common in aquatic ecosystems and imposes a significant challenge for fish farming. The loss of equilibrium (LOE), 50% lethal time (LT50), plasma cortisol, glucose, red blood cells (RBC), hemoglobin (Hb), gill histological alteration, and related parameters (lamellar length [SLL] and width [SLW], interlamellar distance [ID], basal epithelial thickness [BET], lamellar surface area [LA], and gill surface area [GSA]); respiratory rate; the proportion of the secondary lamellae available for gas exchange (PAGE); and hypoxia-inducible factor (hif-1α, hif-2α) mRNA expression were determined during progressive hypoxia and reoxygenation (R-0, R-12, R-24 h) to illustrate the underlying physiological response mechanisms in black rockfish Sebastes schlegelii. Results showed that the DO concentration significantly decreased during progressive hypoxia, while DO at LOE and LT50 were 2.42 ± 0.10 mg L−1 and 1.67 ± 0.38 mg L−1, respectively. Cortisol and glucose were significantly increased at LOE and LT50, with the highest levels observed at LT50, and then gradually recovered to normal within reoxygenation 24 h. RBC number and Hb results were like those of glucose. Hypoxia stress resulted in lamellar clubbing, hypertrophy, and hyperplasia. Respiratory frequency significantly increased at LOE and decreased at LT50. Lamellar perimeters, SLL, ID, LA, GSA, and PAGE, significantly increased at LOE and LT50, with the highest values observed at LT50. However, SLW and BET significantly decreased at LOE, LT50, and R-0. These parameters recovered to nearly normal levels at R-24 h. hif-1α mRNAs in gill and liver were significantly upregulated at LOE and LT50, and recovery to normal after reoxygenation 24 h. hif-2α mRNAs in gill was similar to that of hif-1α, whereas hepatic hif-2α mRNAs remained unchanged during hypoxia-reoxygenation. These results indicated that progressive hypoxia stress elevated RBC number, Hb, cortisol, and glucose levels, induced the alteration of gill morphology, increased LA and GSA, stimulated respiratory frequency and PAGE, and upregulated the transcription of hif-1α and hif-2α in gill and liver. Reoxygenation treatment for 24 h alleviated the stress mentioned above effects. These findings expand current knowledge on hypoxia tolerance in black rockfish Sebastes schlegelii.
... Increased concentrations of total dissolved and labile copper in seawater have been related to handling of nets treated with copper-based antifouling paint (Kalantzi et al., 2016) and copper fragments and antifouling coating particles have been found among water sample sediments after in situ net cleaning Napsøy, 2020). Studies on potential bioaccumulation of copper released from antifouling paint are conflicting (Comas et al., 2021;Nikolaou et al., 2014;Solberg et al., 2002) and histologic gill lesions ascribed to copper toxicity are not specific for this insult (Al-Bairuty et al., 2013;Malhotra et al., 2020). In the current study no measurement of copper concentration in water or tissue samples were performed and any potential effects of copper exposure during net cleaning is unknown. ...
Article
Regular in situ cleaning of net pens is performed to prevent overgrowth and negative effects of biofouling during the sea phase of salmon production in Norway. Possible negative health effects of in situ net cleaning include a reduction in appetite, increased stress, and gill damage. Gill lesions have been reported after exposure to Ectopleura larynx in laboratory trials, but there is currently little information available on whether exposure to biofouling debris from in situ net cleaning significantly contributes to development of gill disease and reduced gill health of farmed Atlantic salmon (Salmo salar) in sea cages. To assess this, gill tissue from healthy fish (n = 30 per pen/time point) from 3 net pens were collected before, as well as one and eight days after the first net cleaning event after sea transfer. The tissue was examined using a standardized histology scoring system. All fish originated from the same commercial sea site located in North-western Norway and net cleaning was performed as per routine for this site. The level of net fouling was scored using a semiquantitative scoring system ranging from 0 to 6, i.e., from totally clean to heavy fouling. Two pens were moderately fouled, and one had a low degree of fouling. The probability (odds) of fish from moderately fouled net pens having subacute vascular damage (thrombi) in the gills at one day after net cleaning was 2.36 (95% CI 1.21–5.71) times higher compared to fish sampled before net cleaning. When all fish were included in the statistical analysis no difference in the number of fish with the recorded lesions were found across the different sampling points and there was even a small decrease in the probability (odds) of fish having acute vascular lesions at eight days after net cleaning. Our results suggest that exposure to biofouling debris during net cleaning might contribute to development of thrombi/subacute vascular lesions in the gills. However, the proportion of gill tissue affected was low, generally estimated to be less than 1%, and no significant difference in the number of fish with these lesions was found at eight days after net cleaning. Thus, the negative impact of in situ net cleaning on gill health in this study is small and short lived, and the clinical implication of these results remains to be established.
... However, the concern is that the dissolved versus nano forms of metals may have different bioavailabilities and toxicities. 13 It is also becoming apparent that the target organ pathologies from ENMs may differ in both aetiology and magnitude of effect compared to the nearest metal salt (e.g., CuSO 4 compared to nano Cu, Al-Bairuty, et al. 14 ). Consequently, it is vital to know how much of the total metal in the tissue is present in the dissolved and nano forms respectively. ...
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A systematic review of the use of single particle ICP-MS to analyse engineered nanomaterials (ENMs) in biological samples (plants, animals, body fluids) has highlighted that efforts have focused on a select few types of ENMs (e.g., Ag and TiO2) and there is a lack of information for some important tissues (e.g., reproductive organs, skin and fatty endocrine organs). The importance of sample storage is often overlooked but plays a critical role. Careful consideration of the ENM and matrix composition is required to select an appropriate protocol to liberate ENMs from a tissue whilst not promoting the transformation of them, or genesis of new particulates. A 'one size fits all' protocol, applicable to all possible types of ENM and biological matrices, does not seem practical. However, alkaline-based extractions would appear to show greater promise for wide applicability to animal tissues, although enzymatic approaches have a role, especially for plant tissues. There is a lack of consistency in metrics reported and how they are determined (e.g. size limit of detection, and proportions of recovery), making comparison between some studies more difficult. In order to establish standardised protocols for regulatory use, effort is needed to: develop certified reference materials, achieve international agree on nomenclature and the use of control samples, and to create a decision tree to help select the best sample preparation for the type of tissue matrix.
... The histopathological changes in the gill such as edema, epithelial necrosis, the fusion of secondary lamellae, hemorrhage at filaments, hypertrophy of epithelial cells, and sloughing off of epithelial surface are the major effects reported in gills from the fish exposed to various types of pollutants (Mallatt 1985). Fishes exposed to nanometals, gills respond through the generation of edema with the lifting of gill lamellar epithelium by binding to Naþ/ Kþ-ATPase, which results in osmotic imbalance and inhibits the entry of toxins (Al-Bairuty et al. 2013, Pane et al. 2004, Fanta et al. 2003, Stagg & Shuttleworth 1982. In the present study, the gill showed histological changes such as hemorrhage, curling of secondary lamellae, desquamation, necrosis, and hyperplasia of epithelial cells in O.mossambicus exposed to NaAsO 2 . ...
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Acute toxicity of arsenic to Tilapia (Oreochromis mossambicus) and tissue repairing activity of Glycosmis pentaphylla leaf extract and its histological impacts on gill, liver, and kidney tissues were evaluated. Fish were divided into six groups viz. control, group 1, group 2, group 3, group 4, and group 5. 4.87 ppm of NaAsO2 was administrated in group 1, group 3, and group 5. In group 3, after arsenic exposure, 2.5 g of leaf extract of Glycosmis pentaphylla per kg of fish food was added. In group 5, 5g of G. pentaphylla leaf extract per kg of fish food was added. In group 2, 2.5 g of leaf extract per kg of fish food was added and in group 4, 5g leaf extract per kg of fish food was added. The control group showed normal histology of the gill, liver, and kidney. The histological observations revealed the tissue repairing activities in group 2 fish’s gill, liver, and kidney. These results revealed the protective and tissue repairing potential of G. pentaphylla as a feed supplement against NaAsO2 induced toxicity.
... It was noted to cause histopathological changes in rainbow trout (O. mykiss) [35] and gill injury and acute lethality in D. rerio [11], and injuries to liver and gills were found in Epinephelus coioides after CuNPs treatment [36] and in the gills of Solea senegalensis [37]. Toxic effects of nano copper were also prominent in crustaceans [38]. ...
Article
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Metal nanoparticles are used in various branches of industry due to their physicochemical properties. However, with intensive use, most of the waste and by-products from industries and household items, and from weathering of products containing nanoparticles, end up in the waters. These pollutants pose a risk to aquatic organisms, one of which is a change in the expression of various genes. Most of the data that focus on metal nanoparticles and their effects on aquatic organisms are about copper and silver nanoparticles, which is due to their popularity in general industry, but information about other nanoparticulate metals can also be found. This review aims to evaluate gene expression patterns in aquatic organisms by metal nanoparticles, specifying details about the transcription changes of singular genes and, if possible, comparing the changes in the expression of the same genes in different organisms. To achieve this goal, available publications tackling this problem are studied and summarized. Nanometals were found to have a modulatory effect on gene expression in different aquatic organisms. Data show both up-regulation and down-regulation of genes. Nano silver, nano copper, and nano zinc show a regulatory effect on genes involved in inflammation and apoptosis, cell cycle regulation and ROS defense as well as in general stress response and have a negative effect on the expression of genes involved in development. Nano gold, nano titanium, nano zinc, and nano iron tend to elevate the transcripts of genes involved in response to ROS, but also pro-apoptotic genes and down-regulate DNA repair-involved genes and anti-apoptotic-involved genes. Nano selenium showed a rare effect that is protective against harmful effects of other nanoparticles, but also induced up-regulation of stress response genes. This review focuses only on the effects of metal nanoparticles on the expression of various genes of aquatic organisms from different taxonomic groups.
... In this work, we set to investigate the combined effect of copper and PCV MPs on metal accumulation and toxicity in common carp, Cyprinus carpio. Copper is a well-known toxicant in aquatic life, particularly in fish, with a variety of negative effects including induction of oxidative stress, apoptosis, inflammation, and histopathological lesions (Al-Bairuty et al., 2013;Pereira et al., 2016). The interaction between MPs and adsorbed metals such as copper is extremely relevant in aquatic (both coastal and freshwater) ecosystems, which are often exposed to high quantities of pollutants due to their proximity to industrialized and urban areas (Wong et al., 2020). ...
Article
The combined effects of copper and polyvinyl chloride (PVC) microparticles were investigated on the metal accumulation, histopathological biomarkers, and targeted transcriptomics in Cyprinus carpio liver. The fish were exposed to 0.25 mg/L copper and/or 0.5 mg/L PVC microparticles over a 14-d period. The results showed that hepatic copper accumulation is facilitated by the PVC microparticles presence in water. All treatments induced significant hepatic stress and inflammation; however, the transcriptional responses involving in detoxification pathways and apoptotic mechanisms were mixed and often down-regulated in the fish exposed to copper and/or PVC microparticles. Exposure to copper and/or PVC microparticles induced hypermeia, leukocyte infiltration and increase in melanomacrophage centers number and area. Generally, the severity of the lesions was in the following order: PVC microparticles < copper < copper+ PVC microparticles. In conclusion, PVC MPs act as a copper vector, facilitating accumulation of copper in the fish liver and increasing the tissue damage.
... Cu is an essential trace element and cofactor of several enzymes, and it is involved in physiological pathways such as heme synthesis and iron absorption (62). Previous histopathological examination found that Cu could cause kidney dysfunction, characterized by degeneration of tubule cells (apoptotic or necrotic) (63,64). An experimental study showed a time-dependent increase in apoptosis in chickens exposed to Cu. Increased apoptosis index and leakage of blood urea nitrogen (BUN) and creatinine suggest that Cu may lead to kidney dysfunction (65). ...
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Background Environmental exposure to toxic elements contributes to the pathogenesis of chronic kidney disease (CKD). Few studies focus on the association of urinary metals and metalloids concentrations with the urinary albumin/creatinine ratio (UACR) among elderly, especially in areas and seasons with severe air pollution. Objective We aimed to evaluate the associations of urinary metals and metalloids concentration with UACR, which is an early and sensitive indicator of CKD. Method We conducted a cross-sectional study among 275 elderly people in Beijing from November to December 2016, which has experienced the most severe air pollution in China. We measured 15 urinary metals and metalloids concentration and estimated their association with UACR using a generalized linear model (GLM). Bayesian kernel machine regression (BKMR) and quantile g-computation (qgcomp) models were also conducted to evaluate the combined effect of metal and metalloid mixtures concentration. Results Of the 275 elderly people included in the analysis, we found that higher urinary Cu concentration was positively associated with UACR using GLM (β = 0.36, 95% CI: 0.25, 0.46). Using the BKMR model, we found that the change in UACR was positively associated with a change in urinary Cu concentration from its 25th to 75th percentile value with all other metals and metalloids concentration fixed at their 25th, 50th, or 75th percentile levels. Urinary Cu concentration had the most significant positive contribution (59.15%) in the qgcomp model. Our finding was largely robust in three mixture modeling approaches: GLM, qgcomp, and BKMR. Conclusion This finding suggests that urinary Cu concentration was strongly positively associated with UACR. Further analyses in cohort studies are required to corroborate this finding.
... On the other hand, warming temperature may rise toxicity of xenobiotics, like copper sulphate, which is a versatile chemical extensively used in industry, agriculture and, most importantly, fish farming (Ashish et al., 2013). Its toxicity can be changed by factors such as temperature and low level of dissolved oxygen, being these a major concern, inducing thermal and severe hypoxia stress on fish (Al-Bairuty et al., 2013) leading to stress-on-stress effect. ...
... Our results are consistent with the studies mentioned above, having shown histological changes comparable to the results of overexposure. Studies have found abnormalities in the renal structures of other fish as a result of exposure to metal-contaminated waters, including a reduced renal hematopoietic system, tissue damage, necrosis, glomerular lesions, connective tissue proliferation, and glomerular and epithelial tubule contraction [1,22,68,69]. ...
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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.
... Cu is an essential trace element and cofactor of several enzymes, and it is involved in physiological pathways such as heme synthesis and iron absorption (Barceloux 1999). Previous histopathological examination found that Cu could cause kidney dysfunction, characterized by degeneration of tubule cells (apoptotic or necrotic) (Al-Bairuty et al. 2013;Eadon et al. 2013). An experimental study showed a timedependent increase in apoptosis in chickens exposed to Cu. Increased apoptosis index and leakage of blood urea nitrogen (BUN) and creatinine suggest that Cu may lead to kidney dysfunction . ...
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Metal exposure contributes significantly to the pathogenesis of kidney dysfunction. However, most studies have focused on metal concentration in a single matrix (i.e., blood or urine), and few have explored the associations of metal clearance and visit-to-visit variability with renal function. We conducted a three-wave repeated-measures study of 201 older adults. Metal clearance and visit-to-visit variability were calculated to reflect, respectively, the body burden and homeostasis of meals. Renal function was measured as the urinary albumin-to-creatinine ratio (UACR) and estimated glomerular filtration rate (eGFR). Linear mixed-effects and Bayesian Kernel Machine Regression models were used to evaluate the effects of single metals and metal mixtures. The blood metal mixture was negatively associated with eGFR, and urinary Cu was positively associated with UACR (β = 0.417). The metal clearance ratios of Cu, Ni, and Sr were significantly and negatively associated with eGFR, and Cu had the largest effect estimate. The variability independent of the mean of urinary Cs was negatively associated with eGFR after adjustments for the individual metal mean concentration (IMM) of urinary Cs. Furthermore, the visit-to-visit variability of blood Sr was significantly and positively associated with UACR and independent of IMM. Among eight meals in blood and urine, urinary Cu contributed the most to the increase in UACR. We firstly proposed metal clearance and visit-to-visit variability, and found the new indicators are associated with kidney dysfunction. This study revealed real-world metal exposure from the perspective of metal mixtures and improved the understanding of the pathophysiology of metal exposure-induced kidney dysfunction. Graphical Abstract
... Copper-and MPs-induced intestinal lesions have been previously reported in fish (Al-Bairuty et al., 2013;Hamed et al., 2021;Maharajan et al., 2016;Pedà et al., 2016). The pigments observed in the intestine of the fish of the Cu and Cu-MPVC treatments might be related to the presence of copper since they were not observed in the MPVC group. ...
Article
The present study aimed at assessing the singular and combined effects of water copper and polyvinyl chloride microplastic (MPVC) on intestinal copper accumulation, histopathological damage, and stress-/immune-related genes' expression in common carp, Cyprinus carpio. Four groups of fish were maintained in triplicate: control (kept in clean water), Cu (exposed to 0.25 mg/L of copper), MPVC (exposed to 0.5 mg/L of MPVC), and Cu-MPVC (exposed to 0.25 mg/L of copper + 0.5 mg/L of MPVC). After 14-day exposure, the fish of Cu and Cu-MPVC treatments exhibited significantly higher intestinal copper contents, compared to the fish of control and MPVC treatments. In this regard, the Cu-MPVC fish had significantly higher copper content than the Cu fish. Exposure to copper and/or MPVC significantly upregulated the intestinal heat shock protein 70 (hsp70), cytochrome P450 family 1 subfamily A member 1 (cyp1a1), lysozyme (lys), defensin (def), mucin 2 (muc2), and mucin 5 (muc5) expression. The highest expression of hsp70, cyp1a1, lys, and def was related to Cu-MPVC treatment; whereas, the highest expression of muc2 and muc5 was observed in Cu and MPVC treatments. Exposure to copper and/or MPVC induced intestinal damage, which Cu-MPVC fish exhibited the highest severity. The present study revealed that exposure to copper and/or MPVC causes intestinal histopathological damage and upregulation in stress- and immune-related genes' expression. The most serious effects were observed in Cu-MPVC treatment that might be due to additive effects of copper and MPVC and/or higher copper accumulation in this treatment. Highlights • Presence of polyvinyl chloride microparticles (MPVC) in Cu-contaminated water increase fish' intestinal copper • Copper and/or MPVC upregulate intestinal stress- and immune-related gene expressions • Copper and/or MPVC induce histopathological damages to the fish intestine • Coexposure to copper and MPVC increases the negative changes in the fish intestine
... Previous studies have also noted the cytotoxic effects of NPs (Chen et al., 2011;Choi et al., 2010;Farkas et al., 2010). The liver is a major target organ that sequesters many environmental contaminants, including metals, and is the main organ for intermediary metabolism and energy storage (Al-Bairuty et al., 2013;Chen et al., 2011;Griffitt et al., 2013;Kwok et al., 2012;Scown, Santos, et al., 2010;Shaw & Handy, 2011). An increase in HSI signifies an increase in the total size of the liver compared to the body, as was seen in rainbow trout at both concentrations tested. ...
Article
Information on the effects of silver nanoparticles (AgNPs) in fish have mostly been generated from standard laboratory species and short‐term toxicity tests. However, there is significant uncertainty regarding AgNP toxicity to native species of concern in North America, particularly in northern freshwater ecosystems. Here, we assessed the chronic toxicity of AgNPs in early life stages of three North American fish species: rainbow trout (Oncorhynchus mykiss), lake trout (Salvelinus namaycush) and northern pike (Esox lucius). Newly fertilized embryos were exposed to nominal aqueous concentrations of 0.1, 0.3, 1.0, 3.0, 10.0, or 30.0 nM AgNPs for 126 (rainbow trout), 210 (lake trout), and 25 (northern pike) days. Endpoints included cumulative developmental time (o C x day or degree‐days to 50% life stage transition), mortality, fork length, embryonic malformations, cumulative survival, and histopathology of gill and liver in larvae/alevins. Results showed life stage‐specific differences in responses, with endpoints during the embryonic stage occurring more often and at lower concentrations, compared to larval/alevin and juvenile stages. Sensitivities among species were highly dependent upon the endpoints measured although developmental time appeared to be the most consistent endpoint across species. At embryonic and larval/alevin stages, northern pike was the most sensitive species (lowest observable effect concentration of 0.1 nM using developmental time). Rainbow trout displayed similar responses to lake trout across multiple endpoints and therefore seems to be an adequate surrogate for trout species in ecotoxicology studies. Moreover, while mortality during individual life stages was not generally affected, the cumulative mortality across life stages was significantly affected, which highlights the importance of chronic, multi‐life stage studies. This article is protected by copyright. All rights reserved.
... Oxidative stress caused by Cu can lead to lipid peroxidation, which damages the cell membrane and loses its normal function, and ultimately causes the release of cytosolic enzymes into the blood (Hoseini et al., 2016). Therefore, increase of AST and ALT activities in serum of fish is often regarded as biomarkers of liver damage which caused by heavy metal (Al-Bairuty et al., 2013). In this research, EC led to remarkable rises of ALT activity in serum and AST and ALT activities in hepatopancreas, which was similar to the research in freshwater prawn (Macrobrachium rosenbergii) that excessive dietary Cu (≥ 51.1 mg/kg diets) remarkably increased hepatopancreas AST and ALT activities (Muralisankar et al., 2016). ...
Article
Raw materials for making dried shrimp (a type of foodstuff) are mostly from farmed shrimp and preliminary findings indicated that head copper (Cu) concentrations in some commercial dried shrimp products exceeded the safe limit specified in pollution-free aquatic products (50 mg/kg), which may influence food safety. Therefore, a 63-day feeding trial was conducted to explore effects of dietary Cu concentrations on accumulation of Cu in tissues, growth performance, immune response and antioxidant status of Pacific white shrimp (Litopenaeus vannamei). Moderating effect of myo-inositol (MI, adding 200 mg/kg diet) on the adverse impacts caused by excessive dietary Cu was also investigated. 600 shrimp (initial weight: 0.89 ± 0.00 g) were divided into five groups: 37.08 mg Cu/kg diet group (control group), 62.57 mg Cu/kg diet group, 125.99 mg Cu/kg diet group, 63.41 mg Cu/kg diet group (supplemented with MI) and 119.19 mg Cu/kg diet group (supplemented with MI). The results showed that dietary Cu concentrations increased from 37.08 to over 62.57 mg/kg, hepatopancreas Cu concentrations raised from 29.04 to 233.43–263.65 mg/kg, and muscle Cu concentrations only increased from 6.22 to 6.99–8.39 mg/kg. Report to control group, excessive Cu concentration (125.99 mg/kg) didn’t significantly affect growth performance, but it notably reduced whole body lipid content and immune response, induced oxidative stress and damaged the hepatopancreas structure, which was ameliorated by MI supplementation. The results suggested that consuming shrimp head and its processed products weren’t recommended. Cu concentrations of commercial feeds for Pacific white shrimp should be controlled below 62.57 mg/kg. Additionally, MI supplementation mitigated the negative impacts induced by excessive dietary Cu.
... including Copper nanoparticles are widely which used as wood preservatives, additives in lubricants, inks, and in plastics to reduce friction (Sau and Rogach., 2010;Kwon et al., 2012;Liu, et al., 2004) and to reduce the growth of microorganisms such as fungi (Cioffi et al., 2005) Copper nanoparticles cause a range of toxic effects such as hemolysis and jaundice, stimulate a range of toxic activities in the liver, such as cirrhosis (Zietzet al., 2003). Studies have shown that kidneys, liver, and spleen being the main target organs of copper particles with regard to acute toxicity which may lead to death in mice (Manna et al., 2012;Sarkar and Das, 2006;Liao and Liu, 2012;Chen et al., 2006) A study of AL-Bairuty et al. (2013), which dealt with the pathological effects of copper nanoparticles and copper sulfate on Oncorhynchus mykiss trout, reported hepatitis in addition to lacerations in renal tubes when trout were exposed to copper nanoparticles at a concentration of 100 mg/kg and for multiple time periods. A comparison study was made between titanium oxides, copper, zinc and iron nanoparticles, with regard to toxicity and DNA damage, and the results showed that copper nanoparticles are the most effective in terms of cytotoxicity and DNA damage (Kim et al., 2009). ...
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The ability of nanoparticles as anti-bacterial materials has led to their widespread application in many health products. However, there are many concerns about the exposure of individuals to these particles, addressed the cellular effects caused by copper nanoparticles on the kidneys using transmission electron microscopy, and investigating the potential therapeutic role of vitamin E and C against the toxicity of copper nanoparticles and their cellular harmful effects. The study used 56 rats (Rattus norvegicus) divided into seven groups and dosed over a month with copper nanoparticles and then dosed for another month with both vitamins E and C, either alone or together, the results showed that the animals of the groups that were treated with copper nanoparticles showed micro-structural changes in the kidneys. Changes were found in the renal tissue at the level of the podocytes forming the endothelial cells in the visceral layer of the renal glomeruli. It was also observed that mitochondria were affected in the epithelial cells of the Proximal convoluted tubules. In addition to an increase in the number of lysosomes and cytoplasmic vacuoles. The effective therapeutic role of vitamin C, E has been shown in improving the size and number of organelles and returning them to their almost normal state. The study recommends the need to use vitamins C and E at a dose of 250 mg/kg/day, which showed a positive role in reducing the toxicity of copper nanoparticles.
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Nanotechnology has emerged as a pulsating field of research which can transform a range of industries including aquaculture. This review paper focuses on some useful prospects of nanotechnology in aquaculture especially on fish with its rationality. Aquaculture industry is constantly suffering from many unaddressed issues related to boost up of its production to meet the ever-increasing demand of the consumers. Several nanoparticles have already been tested for the development and growth of fishery sector viz. disease management, water management, drug and nutrient delivery, growth promotion and sex reversal on some of the economically important fish species. This tool will help millions of fish farmers for better management of fish farms, aquatic ecology and to improve the production of healthy aqua crop and subsequently to uplift their socioeconomic condition. It will be a praiseworthy endeavor to investigate their applications in different areas of fisheries sector.
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Aquaculture has emerged as fastest-growing global food production sector and played a pivotal role in meeting increased animal protein requirement. However, chemical pollution, environmental deterioration and disease prevalence has raised concern about aquaculture sustainability as well as achieving global food security. Nanoparticle nutraceuticals has tremendous potential to cope with these challenges and revolutionize aquaculture sector. The nanoparticle nutraceuticals concept is widely used to solve the challenges like aquaculture production, prevention and treatment of diseases, drug and nutrient delivery and water quality management. Accordingly, this review paper critically addressed the recent advancements on applications of nanoparticle nutraceuticals in aquaculture sector with particular emphasis on disease prevention, water quality management, vaccination and delivery of drugs and nutrients. Additionally, this study sheds on different synthesis methods of nanoparticle nutraceuticals. Further, for its effective use recent updates on smart delivery of nutraceuticals using innovative nanotechnological techniques will also be addressed in this brief review paper. Finally, the challenges and future feasibility of nanoparticle nutraceuticals applications in sustainable aquaculture development will be delineated. This information could be beneficial to policy makers and stakeholders for achieving sustainable aquaculture.
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Changes in Differential Leucocyte Count (DLC) were evaluated in the blood of the fish species Clarias batrachus and this was used as an in situ indicator of the species’ exposure to zinc.Due to feeding and living in the aquatic environments, fish are particularly vulnerable and are heavily exposed to pollution because they cannot escape from the detrimental effects of pollutants. In the present study, the effects of zinc on the DLC(small and large lymphocytes, neutrophils, monocytes, eosinphils and basophils) were examined under three different concentrations of zinc (1.00 ppm, 3.00 ppm and 6.00 ppm) during 7, 14, 21 and 28 days exposure period. During examination, the percentage of both lymphocytes were significantly lower as exposure time and concentration increased while in the case of neurtophils and monocytes, counts, were higher. Eosinophils showed slight increase whereas basophils showed fluctuations in their results. The study of this research infers that the essential metal in undesirable condition can affect the fish health. DLC represents a suitable biomarker of environmental health and provides a tool for biomonitoring water quality.
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Green evolutionary products such as biologically fabricated nanoparticles (NPs) pose a hazard to aquatic creatures. Herein, biogenic silver nanoparticles (AgNPs) were synthesized by the reaction between ionic silver (AgNO3) and aqueous onion peel extract (Allium cepa L). The synthesized biogenic AgNPs were characterized with UV–Visible spectrophotometer, XRD, FT-IR, and TEM with EDS analysis; then, their toxicity was assessed on common carp fish (Cyprinus carpio) using biomarkers of haematological alterations, oxidative stress, histological changes, differential gene expression patterns, and bioaccumulation. The 96 h lethal toxicity was analysed with various concentrations (2, 4, 6, 8, and 10 mg/l) of biogenic AgNPs. Based on 96 h LC50, sublethal concentrations (1/15th, 1/10th, and 1/5th) were given to C. carpio for 28 days. At the end of experiment, the bioaccumulations of Ag content were accumulated mainly in the gills, followed by the liver and muscle. At an interval of 7 days, the haematological alterations showed significance (p < 0.05) and elevation of antioxidant defence mechanism reveals the toxicity of biogenic synthesized AgNPs. Adverse effects on oxidative stress were probably related to the histopathological damage of its vital organs like gill, liver, and muscle. Finally, the fish treated with biogenic synthesized AgNPs were significantly (p < 0.05) downregulates the oxidative stress genes such as Cu–Zn SOD, CAT, GPx1a, GST-α, CYP1A, and Nrf-2 expression patterns. The present study provides evidence of biogenic synthesized AgNPs influence on the aquatic life through induction of oxidative stress.
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Copper (Cu) is a vital micronutrient required for numerous fundamental biological processes, but excessive Cu poses potential detrimental effects on public and ecosystem health. However, the molecular details linking endoplasmic reticulum (ER) stress and apoptosis in duck renal tubular epithelial cells have not been fully elucidated. In this study, duck renal tubular epithelial cells exposed to Cu sulfate (CuSO4) (0, 100 and 200 μM) and a PERK inhibitor (GSK2606414, GSK, 1 μM) for 12 h were used to investigate the crosstalk between ER stress and apoptosis under Cu exposure. Cell and ER morphological and functional characteristics, intracellular calcium (Ca²⁺) levels, apoptotic rates, ER stress and apoptosis-related mRNA and protein levels were examined. The results showed that excessive Cu could cause ER expansion and swelling, increase the expression levels of ER stress-associated genes (PERK, eIF2α, ATF4 and CHOP) and proteins (p-PERK and CHOP), induce intracellular Ca²⁺ overload, upregulate the expression levels of apoptosis-associated genes (Bax, Bak1, Caspase9 and Caspase3) and the cleaved-Caspase3 protein, downregulate Bcl-xl and Bcl2 mRNA levels and trigger apoptosis. PERK inhibitor treatment could ameliorate the above changed factors caused by Cu. In conclusion, these findings indicate that excessive Cu could trigger ER stress via activation of the PERK/ATF4/CHOP signaling pathway and that ER stress might aggravate Cu-induced apoptosis in duck renal tubular epithelial cells.
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This paper provides the current state of knowledge available from the literature regarding the use of copper sulphate (CuSO4) in culture of freshwater and marine fish as related to toxicity, growth performance, physiology, immunity, histomorphology and antiparasitic treatment. From this review, I have assessed and discussed all of these factors, as well as the potential strategies available for use in fish farming. Acute toxicity (96h-LD50) to CuSO4 varies widely among fish species (0.001–730 mg/L) depending on various water quality factors, and many fish species are sensitive to concentrations near those required for controlling and treating parasite infections. Acute exposure to CuSO4 may lead to mortality while sublethal exposure in different organism causes changes in feeding and swimming behaviour, growth performance, histomorphology of gills, liver, kidney, and spleen, hematology, blood biochemistry, the antioxidant defense system, and oxygen consumption. After exposure to copper sulphate, copper ions often accumulate in the gills, liver, kidney and spleen, and in the gills provokes changes in mucus and chloride cells, hyperplasia and/or hypertrophy of primary and/or secondary lamellae, edema of the gill epithelium, and lamellar fusion. Long and short-term exposure to copper sulphate may negatively affect the body growth of fish exposed, and control and treat ectoparasite infections that are discussed here. Copper sulphate may be a chemotherapeutic for controlling and treating ectoparasites in farmed fish because of its effectiveness and low cost.
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Clothianidin, one of the latest members of neonicotinoids, is a systemic insecticide of the neonicotinoid group that affects the central nervous system by acting as a nicotinic acetylcholine receptor agonist. Although it is stated that it has no dangerous potential for aquatic organisms, accumulation in water basins is important in terms of environmental toxicity. In this study, the histopathological changes caused by clothianidin applied in subacute application (7 days) form and in environmental doses (3, 15 and 30 µg/L) in the brain, kidney, muscle and gill tissue of juvenile Oncorhynchus mykiss were determined. Parallel to the administration of increasing doses of clothianidin, an increase in the severity of pathological lesions is observed in the brain, muscle, kidney and gill tissue. In particular, it shows that as a result of the accumulation of pesticides in aquatic organisms, lesions may develop as tissue-specific responses, thus leading to tissue dysfunction.
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Pesticide usage is increasing daily leading to destruction of aquatic ecosystems. Consumption of pesti�cide bio-accumulated fish and other aquatic edibles leads to several health hazards in human. Scientists are trying hard to fulfil the demand of the farmers and have emphasised on the formulation and use of advance form of pesticide also known as nano-pesticide. However, the issue of pesticide�related health hazard owing to its continuous accumulation and transformation has been quite alarming in-spite of restriction rules for its usage. This review aims in pointing out and compares the effects of pesticide and nano-pesti�cides-induced toxicity in fish and tries to figure out a possible effective way towards reducing pesticide con�sumed health issues of human race. Through various lit�erature surveys we have tried to club the toxicological impact of pesticides and nano-pesticides in fish body as observed by DNA damage, cellular cytotoxicity, hepatic injury by bioaccumulation in tissue and alteration in behavioural, physiological, biochemical parameters in one platform. Additionally, an alternative phyto-based remedy was also surveyed with special emphasis on PLGA nanocarrier system to formulate nano-particles which was not only non-toxic when delivered in fish body but also biodegradable in nature and thus was found to be a promising way to control the extreme level of health hazard issues due to pesticidal effect. Thus, the phyto-based nano�formulations might serve as one of the most potent alternative strategy in addressing all the global issue of pesticide toxicity.
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Copper nanoparticles (Cu-NPs) are water pollutants, which has significant toxic environmental effects. However, the effects of Cu-NPs on Takifugu fasciatus are still relatively unknown. Compared with the control (no add CuSO4 and Cu-NPs). This study aims to describe the pathological changes in the gill and liver of pufferfish exposed to CuSO4 (Cu²⁺ for short) and Cu-NPs dissolved at a concentration of either 20 or 100 μg/L, in a semi-static waterborne exposure regime for 28 days. All Cu treatments resulted in organ injuries, and the pathologies observed following exposure to Cu-NPs were broadly of the same type as those observed following exposure to Cu²⁺. In the gill, these included lamellar fusion, clubbed tips, and mucocytes swollen, and in the liver included oedema, aggregation of blood cells, and necrosis. Furthermore, enzyme activity assays revealed that Ca²⁺ -ATP activity significantly increased under the influence of Cu, whilst Na⁺-K⁺-ATPase activity was significantly inhibited. In this study, the CRT in T. fasciatus (referred to as TfCRT) was identified and full-length cDNA sequences were characterized. Subsequently, RT-PCR and western blot analysis were carried out to assess the expressions of TfCRT in the gill and liver at both the mRNA and protein levels. Under both the Cu-NPs and Cu²⁺ treatments, both the mRNA and protein expressions of TfCRT were considerably higher in the gill and liver compared to that of the control treatment. Furthermore, there were no significant differences between Cu-NPs and Cu²⁺ treatment (at the same treatment concentration) in the expressions of TfCRT at the mRNA or protein levels. Overall, both Cu²⁺ and Cu-NPs had negative effects on T. fasciatus, and Cu-NPs had the toxic effects similar to dissolved Cu. Our results provide the ecological safety data service of Cu-NPs in water, and provide a reference for the health T. fasciatus aquaculture.
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Abstract The current study was conducted to study concentrations of some heavy metals (iron, zinc and copper) and some environmental conditions and physiological and histological effects on cage fish and wild fish of common carp type in Euphrates River for a year from October of 2018 until November of 2019 Three sites were selected: first site in Abu Luka, in Musayyib district, near the thermal station for energy production, second site was in the district of al-Sadda near the cement plant, and third site was chosen in an area we add it in village of Al-Husayn. Samples were taken from river sediments for purpose of estimating level of heavy metals, and sample was take from fish including brain, liver, gills, and muscles for purpose of estimating heavy metals, conducting a histological examination and drawing blood from fish to check blood components, as well as to estimate liver enzymes. The results showed that content of heavy metals in sediments was higher in first and second sites than in third site, and concentration of heavy metals in members of studied fish was also higher in second site, followed by first site and finally with the lowest values of third site. In general, cage fish in first and second sites were higher than Wild fish with its content of heavy metals because it is kept close to sources of pollution. As for third site, wild fish had highest level of heavy metals due to their obtaining of pollutants from food. Summer> Spring> Autumn > Winter and this is due to correlation between studied environmental properties and concentration of heavy metals, so they had a correlation with both temperature and vital oxygen requirement and inversely with pH, salinity, dissolved solids and dissolved oxygen. The results of blood test showed that white blood cells increase in areas that contain a higher concentration of heavy metals, and lymphocytes, monocytes and granule cells also increase with high concentrations of heavy metals. As for red blood cells, their number decreases with increase in concentration of heavy metals, hemoglobin and the mean corpuscular hemoglobin, and mean capsular hemoglobin concentration in the red blood cells decreases with increase in concentrations of heavy metals studied, its value decreased in both first and second sites, while Hematocrit and Mean corpuscular volume increased with rising in concentration of heavy metals, their value increased in first and second sites compared to third site,The results concluded that liver enzymes are directly affected by presence of high concentrations of heavy metals, so both alanine transporter enzyme and aspartase transport enzyme increased in first and second sites compared to third site. As for alkaline phosphatase enzyme, its value decreased by increasing concentration of studied metals, and it was low in first and second sites compared to third site,The results of histological examination of brain showed cellular degenerative changes in telencephalon brain and metencephalon brain tissue. The pathological damage was characterized by presence of vacuolation between neurons in regions of telencephalon brain and metencephalon brain near stratum periventricular layer with presence of inflammatory cell infiltration and presence of necrosis of neurons and glial cells in visceral tissue The results of histological examinations of liver in first and second sites showed a degeneration in hepatocytes with formation of spaces between hepatic cell and some spaces filled with remains of the shattered cells from tissue of liver with presence of infiltration in inflammatory cells in affected area of liver and the results of histological examinations of wild fish gills of first and second showed hyperplasia of epithelial cells between secondary lamella, which fills spaces between secondary lamella that cause compression of adjacent lamella. Also, a case of coagulative necrosis was observed in epithelial cells and plaster cells. As for wild fish in first and second sites, in addition to previous symptoms, there was a case of coagulative necrosis in cells of epithelial tissue and plaster cells, which in turn led to formation of spaces in secondary platelets in addition to infiltration of phagocytes in space between necrotic cells. and infiltration of inflammatory cells in the affected area. The results of histological examinations of muscles of wild fish in first and second sites showed a case of necrosis in muscle cells, which lead to erosion and space formation in muscle fibers, while cage fish in first and second sites, in addition to above, showed existence of outer borders of muscle fibers without presence of muscle cells inside them,It should be noted that zinc concentration was among international determinants of both World Health Organization, Canadian Standards and Environmental Protection Agency, but it is higher than limit of the Food and Agriculture Organization for year 2004. The value of copper was higher than international determinants of World Health Organization and Food and Agriculture Organization and Canadian specifications, but it is within permissible limits. By US Protection Agency. This is first study in region that deals with effect of levels of heavy metals in environment on cage fish and their relationship to blood parameter and liver enzymes.
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Aquaculture represents the fastest growing agricultural sector and supports increasing demand for animal proteins and fats. In contemporary times, its prolific growth potential has been challenged by multiple abiotic stressors, including climate change, pollution, water scarcity, etc. Alternatively, increased disease susceptibility, the emergence of new pathogens, and low efficacy of conventional theragnostic tools appear to be the major bottlenecks in tackling sustainability. Nanotechnology has emerged as an innovative and efficacious tool in the field of fish nutrition, biotechnology, genetics, reproduction, pathology and sustaining environmental quality etc. The application of nano-elements enriched feed has deliberately enhanced the fish growth. Emerging nano-materials are currently applied in aquatic system to reduce treatment costs by wiping off pollutants. Genetically manipulated techniques, in combination with nano-biotechnology has revolutionized fish genetics research. Newer usages of nano-sensors, DNA nano-vaccines, nano-inspired genes, and drug delivery systems have reformed the fish health, reproduction, and immune system. In addition, nanotechnology are currently being employed in fish processing industry for sterile packaging, exact flavor, and quality. Optimum utilization of fishery wastes using bio-nano-engineering technique and implication of green nanoparticles have ushered a novel post-harvesting era. Dimensions of applied nanotechnology in the aquatic system are still on the verge of initiation. The present review aimed to provide an in-depth screening into the novel and versatile applications of nanotechnology in aquaculture alongwith its prospects and challenges.
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Toxicological tests of salmons on acute and chronic critical concentrations of 15 chemical elements (Cu, Zn, Pb, Co, Ni, Mn, Sb, Al, Fe, Mo, V, Se, S, As, B) are executed and compared with cited data, with special attention to mechanisms of the toxins physiological effects on fish, including their synergistic and antagonistic influence. These elements are the most common pollutants of spawning rivers in Kamchatka. For better comparability, the standard test object is used, as rainbow trout. Regional amendments to the normative standards of anthropogenic discharges are proposed.
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This study tests the hypothesis that rainbow trout (Oncorhynchus mykiss) compensate for the metabolic cost of dietary Cu exposure by reducing swimming activity at particular times during the diel cycle. Fish were exposed to excess dietary Cu for three months (726 mg Cu·kg–1 dry weight) and simultaneously oxygen consumption (MO2) and spontaneous swimming activity were measured. Rhythmicity in swimming activity was examined by videorecording fish behaviours for 48 h. Standard metabolic rate estimates (RS) of 7.2 and 8.7 mmol O2·kg–1·h–1 (15°C) were measured for control and Cu-exposed fish, respectively. MO2 was higher in Cu-exposed fish at any chosen speed compared with control Cu-exposed trout, which decreased activity (mean speed) by at least 75%, spent more time at lower speeds, and lost circadian periodicity in these parameters compared with controls. Mean growth rates were normal, although Cu-exposed fish showed a narrower range of body weights and fewer mortalities than control groups, suggesting a suppression in social behaviour in Cu-exposed fish. Overall, the increased metabolic cost of swimming in Cu-exposed fish was fully compensated by a reduction in activity, particularly at night and dawn. However, this behavioural strategy suggests that spatial and temporal aspects of ecologically important social behaviours may be compromised in Cu-exposed fish.
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The aim of this study was to obtain a holistic view of the sublethal toxic responses, and compensations, of fish exposed to Cu in the diet. Rainbow trout were fed to appetite on either a Cu-loaded diet (500 mg Cu kg−1 dw) or a control diet (11.9 mg Cu kg−1 dw) for 3 months. Nutritional performance, blood and muscle chemistry, histology, respiration, and swimming behaviour were measured. Copper concentration in intestine and liver of exposed fish was 16 and 2.5 times greater than in controls respectively, confirming oral Cu exposure. [Cu] remained low in the gills of fish irrespective of Cu treatment (<0.096 μmol g−1 dw). Hepatic and intestinal metallothionien levels increased 8- and 1.5-fold, respectively, in Cu-treated fish compared to controls. Growth rate, appetite, food conversion ratios, carcass composition, oxygen consumption and ventilation rate in exposed fish were not different from controls. There were no treatment related changes in serum chemistry (glucose, triglycerides, protein, Na, K, Hb) or the mineral composition of skeletal muscle (Ca, Mg, Zn, Na, or K). However, quantitative histology showed a 9% increase in gill secondary lamellae length, together with lipid depletion in the livers of copper treated fish compared to controls. Routine swimming activity was affected significantly by oral Cu exposure. Time spent swimming was 35% lower in Cu-exposed fish after 3 months, while total distance moved was reduced by only 21% because mean swimming speed was 12% higher in contaminated fish. Maximum speeds attained by exposed fish were not different compared to controls. Exposed fish lowered activity overall by decreasing time spent swimming at low (1–17 cm s−1) and medium speeds (17–40 cm s−1), whilst increasing proportionately time spent fast swimming (40–58 cm s−1). These results are discussed in terms of sub-lethal oral Cu affecting the partitioning of energy utilisation between locomotion and maintenance metabolism by trout in a physiological drive towards invariant growth rates.
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Atlantic salmon (Salmo salar) parr were exposed for 4 weeks to dietary Cu concentrations of 5 (control), 35 and 700 mg Cu kg−1 dry feed to establish maximum tolerable levels of dietary Cu. Parr exposed to 35 and 700 mg Cu kg−1 dry feed had significantly increased (P<0.01) intestinal cell proliferation (PCNA) and apoptosis rates, and increased metallothionein (MT) concentrations compared to controls. Those responses were associated with Cu accumulation in the intestine (3.5- and 89.2-fold increases relative to controls, respectively). In contrast to the controls, the Cu-exposed groups did not grow significantly during the exposure period (P>0.05). There were no significant changes in gill Cu, plasma Cu or liver MT levels at any of the dietary Cu concentrations, indicating that Cu homeostasis was maintained. A significant increase in liver Cu (1.6-fold relative to controls), but no significant change in liver MT, were observed only at the highest copper concentration. Cu-exposed Atlantic salmon parr showed an onset of adaptive responses (increase of intestinal PCNA, apoptosis, and MT levels) at concentrations of 35 and 700 mg Cu kg−1 dry feed, indicating that stress responses are induced at these dietary Cu concentrations.
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Hypoxic events frequently occur in the aquatic environment in association with micro pollutants, including heavy metals. Only a few studies are however available on the uptake and biological responses of heavy metals under hypoxic conditions. To elucidate the phenomenon, mirror carp Cyprinus carpio L. (16.13-16.22 g) were exposed chronically to dietary copper (Cu; 250 and 500 mg kg dry wt.(-1)) for 30 d under normoxic (8.25 mg O(2) L(-1)) and hypoxic (~3 mg O(2) L(-1)) conditions and adopting an integrated approach, sub-lethal biomarker responses were determined at different levels of biological organisation. Level of oxidative DNA damage (as determined by modified Comet assay) showed strong significant difference following exposure to dietary Cu level under normoxic (1.6-fold) as well as under hypoxic condition at both Cu levels (2.1 and 2.5-folds respectively). Significant difference was also observed for haematological parameters (i.e. increased red and white blood cells, haematocrit value and haemoglobin concentration). Quantitative histology revealed alterations in tissues (i.e. liver and gills) for hypoxic and all dietary Cu treatment groups under both normoxic and hypoxic conditions suggesting a compensatory response to these organs (p<0.05). The order of Cu accumulation in tissues (as determined by ICP-OES) was liver>intestine>kidney>gill. Interestingly, SGR under both normoxic and hypoxic conditions reduced with elevating Cu levels (p=0.019). Overall, the results provide evidence for enhanced toxicological responses in fish following exposure to Cu either alone or in combination with hypoxic condition and lends support to the evolving viewpoint that many water quality guidelines should be revisited in terms of new ecotoxicological criteria.
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Nanoparticles are small sized (1-100 nm) particles derived from transition metals, silver, copper, aluminum, silicon, carbon and metal oxides that can easily cross the blood-brain barrier (BBB) and/or produce damage to the barrier integrity by altering endothelial cell membrane permeability. However, the influence of nanoparticles on BBB integrity is still not well-known. In this investigation, effect of nanoparticles derived from Ag, Al and Cu (50-60 nm) on BBB permeability in relation to brain edema formation was examined in a rat model. Intravenous (30 mg/kg), intraperitoneal (50 mg/kg) or intracerebral (20 microg in 10 microL) administration of Ag, Cu or Al nanoparticles disrupted the BBB function to Evans blue albumin (EBA) and radioiodine in rats 24 h after administration and induced brain edema formation. The leakage of Evans blue dye was observed largely in the ventral surface of brain and in the proximal frontal cortex. The dorsal surfaces of cerebellum showed mild to moderate EBA staining. These effects were most pronounced in animals that received Ag or Cu nanoparticles compared to Al nanoparticles through intravenous routes. These observations are the first to suggest that nanoparticles can induce brain edema formation by influencing BBB breakdown in vivo.
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The use of nanoscale materials is growing exponentially, but there are also concerns about the environmental hazard to aquatic biota. Metal-containing engineered nanoparticles (NPs) are an important group of these new materials, and are often made of one metal (e.g., Cu-NPs and Ag-NPs), metal oxides (e.g., ZnO and TiO(2) NPs), or composite of several metals. The physiological effects and toxicity of trace metals in the traditional dissolved form are relatively well known and the overall aim of this review was to use our existing conceptual framework of metal toxicity in fish to compare and contrast the effects of nanometals. Conceptually, there are some fundamental differences that relate to bioavailability and uptake. The chemistry and behaviour of nanometals involves dynamic aspects of aggregation theory, rather than the equilibrium models traditionally used for free metal ions. Some NPs, such as Cu-NPs, may also release free metal ions from the surface of the particle. Biological uptake of NPs is not likely via ion transporters, but endocytosis is a possible uptake mechanism. The body distribution, metabolism, and excretion of nanometals is poorly understood and hampered by a lack of methods for measuring NPs in tissues. Although data sets are still limited, emerging studies on the acute toxicity of nanometals have so far shown that these materials can be lethal to fish in the mg-μgl(-1) range, depending on the type of material. Evidence suggests that some nanometals can be more acutely toxic to some fish than dissolved forms. For example, juvenile zebrafish have a 48-h LC(50) of about 0.71 and 1.78mgl(-1) for nano- and dissolved forms of Cu respectively. The acute toxicity of metal NPs is not always explained, or only partly explained, by the presence of free metal ions; suggesting that other novel mechanisms may be involved in bioavailability. Evidence suggests that nanometals can cause a range of sublethal effects in fish including respiratory toxicity, disturbances to trace elements in tissues, inhibition of Na(+)K(+)-ATPase, and oxidative stress. Organ pathologies from nanometals can be found in a range of organs including the gill, liver, intestine, and brain. These sublethal effects suggest some common features in the sublethal responses to nanometals compared to metal salts. Effects on early life stages of fish are also emerging, with reports of nanometals crossing the chorion (e.g., Ag-NPs), and suggestions that the nano-forms of some metals (Cu-NPs and ZnO NPs) may be more toxic to embryos or juveniles, than the equivalent metal salt. It remains possible that nanometals could interfere with, and/or stimulate stress responses in fish; but data has yet to be collected on this aspect. We conclude that nanometals do have adverse physiological effects on fish, and the hazard for some metal NPs will be different to the traditional dissolved forms of metals.
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Silver nanoparticles (AgNPs) may induce deleterious effects in aquatic life on environmental release. The hepatotoxicity of AgNPs was assessed in the liver of adult zebrafish, with the aim of studying the roles of oxidative damage and apoptosis. Zebrafish were exposed to an AgNP solution in which free Ag+ ions were absent at the time of treatment. However, the metal-sensitive metallothionein 2 (MT2) mRNA was induced in the liver tissues of AgNP-treated zebrafish, suggesting that Ag+ ions were released from AgNPs after treatment. It is also possible that MT2 mRNA was induced in the liver tissues by AgNP-generated free radicals. A number of cellular alterations including disruption of hepatic cell cords and apoptotic changes were observed in histological analysis of the liver tissues. The levels of malondialdehyde, a byproduct of cellular lipid peroxidation, and total glutathione were increased in the tissues after treatment with AgNPs. The mRNA levels of the oxyradical-scavenging enzymes catalase and glutathione peroxidase 1a were reduced in the tissues. AgNP treatment induced DNA damage, as demonstrated by analysis with the double-strand break marker γ-H2AX and the expression of p53 protein in liver tissues. In addition, the p53-related pro-apoptotic genes Bax, Noxa, and p21 were upregulated after treatment with AgNPs. These data suggest that oxidative stress and apoptosis are associated with AgNP toxicity in the liver of adult zebrafish.
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Increasing application of nanotechnology highlights the need to clarify and understand nanotoxicity. Mammalian and in vitro studies have raised concerns about the toxicity of titanium dioxide nanoparticles (TiO2-NPs), but there are limited data on ecotoxicity to aquatic organisms. In this work, the sub-acute toxicity of TiO2-NPs to carp (Cyprinus carpio) was assessed. Superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) activities and lipid peroxidation (LPO) levels in liver, gill and brain tissues of carps varied with concentration of TiO2-NPs suspensions and exposure time (up to 8 d). As a result, 100 and 200 mg/L TiO2-NPs caused statistically significant decrease in SOD, CAT and POD activities and significant increase in LPO levels in tissues (P < 0.05), suggesting that the fish exposed to these two concentrations of TiO2-NPs suffered from the oxidative stress. The extent of depletion of antioxidant enzymes activities and the elevation of LPO in the liver was the greatest, indicating that the liver might be the most susceptible organ to TiO2-NPs exposure. In addition, carps had gill pathologies including edema and thickening of gill lamellae as well as gill filaments, and liver pathologies including necrotic and apoptosis hepatocytes after exposed to 100 and 200 mg/L TiO2-NPs for 20 d. These results indicated a potential risk from TiO2-NPs released into the aqueous environment.
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Effects of high, medium, and low levels of copper on the morphology of winter flounder were investigated using routine histological techniques and electron microscope analyses.High and medium levels of copper resulted in fatty metamorphosis in the liver, necrosis in the kidney, destruction of the hemopoetic tissue, and gross changes in gill architecture. Seven other structures and organs were examined for copper-induced morphological changes but none were found.Light microscope studies showed that low levels of copper caused an extracted appearance in gill lamellae; the epithelial layer appeared vacuolated; the basi-lamellar region was reduced in thickness. Lamellar mucus cells were few compared with control specimens and chloride cells appeared in their stead.Electron microscope study of gill lamella from fish exposed to low levels of copper confirmed vacuolation in the epithelial layer. Also found were myelinlike figures, various membrane-bound vesicles, and apical homogeneous layers of reduced thicknes...
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Silver nanoparticles are utilised in an increasing amount of products, and discharge to the aquatic environment is inevitable. Fish gills are in direct contact with the ambient water, making them potential exposed and vulnerable to suspended silver nanoparticles. The present study investigates the effect of silver nanoparticles (average 81 nm) on the oxygen consumption (M(O2)) in Eurasian perch (Perca fluviatilis), expressed by the basal metabolic rate (BMR) and the critical oxygen tension (P(crit)) below which the fish can no longer maintain aerobic metabolism. For comparison, the impact of silver nitrate (AgNO(3)), was examined as well. Perch were exposed to nominal concentrations of 63, 129 and 300 microg L(-1) silver nanoparticles and 39 and 386 microg L(-1) AgNO(3), respectively, plus controls which were not exposed to silver. M(O2) measured by automated intermittent closed respirometry. After one day acclimatization in the respirometer, the pre-exposure BMR was determined together with P(crit). Hereafter, nanoparticles or silver nitrate were added to the test tank and BMR and P(crit) were measured again the following day. The results demonstrate that nanosilver had no impact on the BMR, whereas exposure to 386 microg L(-1) AgNO(3) resulted in a significant raise in BMR. P(crit) was increased approximately 50% after exposure to 300 microg L(-1) nanosilver plus 31% and 48% by 39 microg L(-1)and 386 microg L(-1) silver nitrate, respectively. These findings reveal that exposure to nanosilver results in impairment of the tolerance to hypoxia. Possibly, nanosilver affects the gills externally, reducing the diffusion conductance which then leads to internal hypoxia during low water oxygen tensions (P(O2)).
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Goldfish kept in water containing ionized copper and a detergent added with the aim of decreasing coagulation of the mucus on the gills, took in and retained this metal in their brains, livers, and kidneys, in concentrations comparable to those that occur naturally in Wilson's disease, as chemical assays disclosed. Histochemical studies made it clear that much copper had accumulated within the large neurons, principally in those of the telencephalon and anterior horn region of the spinal cord and in the tubular epithelial cells of the kidneys, the nuclei of the parenchymal cells of the liver, the sarcoplasm of the skeletal muscle, and in the epithelial covering of the gills. The intraneuronal deposition of copper was regularly associated after a time with conspicuous cytologic changes, notably contraction and hyperchromaticity of the nerve cells with tortuosity and fragmentation of the axis cylinders and lysis and loss of neurons. The accumulation of metal in the renal epithelium was frequently accompanied by necrosis and was regularly associated with hyperplasia and calcification of the epithelial cells of the larger renal tubules in all goldfish kept for prolonged periods in copper-rich water. The deposition of copper in the liver was not accompanied by consistent cytologic changes. The similarity of the cytologic alterations induced in the central nervous systems by copper and those that occur naturally in hepatolenticular degeneration in human beings provides evidence that copper itself plays an important role in the pathologic alterations of the brain in Wilson's disease.
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This study was undertaken to determine whether calcium could render any protection against copper (Cu) toxicity in Nile tilapia with emphasis on histopathological and histochemical analysis. The copper LC(50) values for 24, 48, 72, and 96 h to tilapia in the laboratory were 210.27, 213.34, 193.30, and 185. 75 mg/L, respectively. Prior to Cu exposure, fish were exposed to 0 (G1 and G3) and 30 mg/L calcium carbonate (G2 and G4) for 4 days. After that, fish were exposed to 46 mg/L copper, which corresponds to 25% of the 96 h LC(50) (G3 and G4) for 96 h and 7 days. In the gills of the copper treatment group, primary filament cell hyperplasia, epithelial lifting, or edema, secondary lamellar fusion, and aneurysm were observed. Swollen hepatocytes showing vacuoles and congestion in sinusoids were observed. Necrosis was observed in some areas. In the kidney, glomerulus's atrophy, tubular swelling, a