Effects of ethanol and sodium phenobarbital on conflict behavior of goldfish (Carassius auratus)

Hungry goldfish learned to press a lever for worms obtainable on a 2 min variable-interval schedule of reinforcement. Conflict was induced by rewarding with a worm and punishing with an electric shock any lever responses made in the presence of a flashing light. The resulting suppression of responding was attenuated in fish exposed to sodium phenobarbital. Ethanol solutions were generally without effect.     

In vitro screening of metal oxide nanoparticles for effects on neural function using cortical networks on microelectrode arrays

Nanoparticles (NPs) may translocate to the brain following inhalation or oral exposures, yet higher throughput methods to screen NPs for potential neurotoxicity are lacking. The present study examined effects of 5 CeO₂ (5– 1288?nm), and 4 TiO₂ (6–142?nm) NPs and microparticles (MP) on network function in primary cultures of rat cortex on 12 well microelectrode array (MEA) plates. Particles were without cytotoxicity at concentrations ≤50?µg/ml. After recording 1?h of baseline activity prior to particle (3–50?µg/ml) exposure, changes in the total number of spikes (TS) and # of active electrodes (#AEs) were assessed 1, 24, and 48?h later. Following the 48?h recording, the response to a challenge with the GABA_A antagonist bicuculline (BIC; 25?µM) was assessed. In all, particles effects were subtle, but 69?nm CeO₂ and 25?nm TiO₂ NPs caused concentration-related decreases in TS following 1?h exposure. At 48?h, 5 and 69?nm CeO₂ and 25 and 31?nm TiO₂ decreased #AE, while the two MPs increased #AEs. Following BIC, only 31?nm TiO₂ produced concentration-related decreases in #AEs, while 1288?nm CeO₂ caused concentration-related increases in both TS and #AE. The results indicate that some metal oxide particles cause subtle concentration-related changes in spontaneous and/or GABA_A receptor-mediated neuronal activity in vitro at times when cytotoxicity is absent, and that MEAs can be used to screen and prioritize nanoparticles for neurotoxicity hazard.     

Accumulation and toxicity of CuO and ZnO nanoparticles through waterborne and dietary exposure of goldfish (Carassius auratus)

Dietary and waterborne exposure to copper oxide (CuO) and zinc oxide (ZnO) nanoparticles (NPs) was conducted using a simplified model of an aquatic food chain consisting of zooplankton (Artemia salina) and goldfish (Carassius auratus) to determine bioaccumulation, toxic effects, and particle transport through trophic levels. Artemia contaminated with NPs were used as food in dietary exposure. Fish were exposed to suspensions of the NPs in waterborne exposure. ICP‐MS analysis showed that accumulation primarily occurred in the intestine, followed by the gills and liver. Dietary uptake was lower, but was found to be a potential pathway for transport of NPs to higher organisms. Waterborne exposure resulted in about a 10‐fold higher accumulation in the intestine. The heart, brain, and muscle tissue had no significant Cu or Zn. However, concentrations in muscle increased with NP concentration, which was ascribed to bioaccumulation of Cu and Zn released from NPs. Free Cu concentration in the medium was always higher than that of Zn, indicating CuO NPs dissolved more readily. ZnO NPs were relatively benign, even in waterborne exposure (p ≥ 0.05). In contrast, CuO NPs were toxic. Malondialdehyde levels in the liver and gills increased substantially (p < 0.05). Despite lower Cu accumulation, the liver exhibited significant oxidative stress, which could be from chronic exposure to Cu ions. © 2014 Wiley Periodicals, Inc. Environ Toxicol 30: 119–128, 2015.     

Effect of microcystin-LR on protein phosphatase activity in fed and fasted juvenile goldfish Carassius auratus L.

Fed and fasted juvenile goldfish Carassius auratus (30 g body weight) were injected intraperitoneally (i.p.) with microcystin-LR (MC-LR) (125 microg/kg body weight) to determine the effect of alimentary status on the hepatic toxicity of MC-LR. The toxin accumulation pattern was similar in both fed and fasted treatments. MC-LR accumulated during the first 48 h post-injection and decreased significantly between 48 and 96 h. MC-LR accumulation induced a decrease in hepatic protein phosphatase activity and glycogen content. Fasted individuals were more severely and more rapidly affected than fed ones. Both indicators were significantly altered after 6 h of fasted treatment. In particular, protein phosphatase activity was totally inhibited after 6 h in the fasted treatment but only lowered and not totally suppressed in the fed one. In both treatments, the recovery of enzyme activity was complete after 96 h. On the other hand, hepatic glutathione concentration and glutathione S-transferase activity were not significantly affected.     

Effects of atrazine on sex steroid dynamics, plasma vitellogenin concentration and gonad development in adult goldfish (Carassius auratus)

Sexually mature goldfish (Carassius auratus) of both sexes were exposed to two doses (100 and 1000 microg/l) of the widely used herbicide atrazine (2-chloro-4-ethylamino-6-isopropylamino-s-triazine) for a period of 21 days and effects on the concentrations of gonad and plasma sex steroids (testosterone (T), 17beta-estradiol (E2) and 11-ketotestosterone (11-KT)), plasma vitellogenin (VTG) and gonad histo-morphology assessed. Atrazine did not show any obvious estrogenic effect in males, as determined by a lack of vitellogenin induction. There were, however, effects of atrazine on plasma androgen concentrations (androgen dynamics) and tissue (plasma and gonad) estrogen concentrations in male goldfish; exposure to 1000 microg/l atrazine induced suppression in both testosterone and 11-ketotestosterone, and resulted in elevated 17beta-estradiol, after 21 day of exposure. Further, these suppressive effects on plasma androgens and the induction in estrogen were dose- and time-related. The highest atrazine exposure dose induced structural disruption in the testis and both 100 and 1000 microg/l induced elevated levels of atresia in ovaries.     

Airway irritation,inflammation, and toxicity in mice following inhalation of metal oxide nanoparticles

Metal oxide nanoparticles are used in a broad range of industrial processes and workers may be exposed to aerosols of the particles both during production and handling. Despite the widespread use of these particles, relatively few studies have been performed to investigate the toxicological effects in the airways following inhalation. In the present study, the acute (24?h) and persistent (13 weeks) effects in the airways after a single exposure to metal oxide nanoparticles were studied using a murine inhalation model. Mice were exposed 60?min to aerosols of either ZnO, TiO₂, Al₂O₃ or CeO₂ and the deposited doses in the upper and lower respiratory tracts were calculated. Endpoints were acute airway irritation, pulmonary inflammation based on analyses of bronchoalveolar lavage (BAL) cell composition, DNA damage assessed by the comet assay and pulmonary toxicity assessed by protein level in BAL fluid and histology. All studied particles reduced the tidal volume in a concentration-dependent manner accompanied with an increase in the respiratory rate. In addition, ZnO and TiO₂ induced nasal irritation. BAL cell analyses revealed both neutrophilic and lymphocytic inflammation 24-h post-exposure to all particles except TiO₂. The ranking of potency regarding induction of acute lung inflammation was Al₂O₃ = TiO_2?<_?CeO₂ ? ZnO. Exposure to CeO₂ gave rise to a more persistent inflammation; both neutrophilic and lymphocytic inflammation was seen 13 weeks after exposure. As the only particles, ZnO caused a significant toxic effect in the airways while TiO₂ gave rise to DNA-strand break as shown by the comet assay.     

Influence of long-term exposure to dietary cadmium on growth, maturation and reproduction of goldfish (subspecies: Prussian carp Carassius auratus gibelio B.)

The influence of long-term exposure of goldfish to dietary cadmium (Cd) on its accumulation in tissues, growth, ovarian development, luteinizing hormone (LH) secretion and a response to hormonal stimulation of spawning were evaluated. The study was conducted on four groups of females for the period of 3 years, from the age of 10 weeks to second spawning. Four doses of Cd were applied in the feed: 0 (control group), 0.1, 1 and 10 mg Cd g(-1) of feed (wet weight). The highest dose of Cd (10 mg g(-1)) inhibited growth and caused several behavioural effects. In contrast, lower dose of Cd (1 mg g(-1)) stimulated fish growth. The doses of Cd from 0.1 to 1 mg Cd g(-1) did not influence ovarian development. The gonado-somatic index (GSI) and histological analysis of ovaries showed no differences in ovarian development between the control group and the groups receiving these doses of Cd. However, in the group receiving the highest Cd dose, GSI decreased. This was associated with persistent, long-lasting elevation of plasma LH levels. Ovulation did not occur in this group. Injections of salmon GnRH-analogue (sGnRHa) alone or with domperidone (a dopamine receptor antagonist) in sexually mature fish caused an increase of LH levels in all groups, although in the group fed with the highest Cd dose the effect was weaker than in the other groups. After the first spawning season, a negative effect of lower Cd doses (0.1 and 1mg Cd g(-1)) on ovarian recrudescence (rebuilding of ovaries) and on the response to the consecutive hormonal stimulation of spawning was observed (lower number of ovulating females). There was a significantly higher content of Cd in the livers of fish than in their muscles. The results of hormonal stimulation of spawning and histological analysis of ovaries suggest that in goldfish cadmium acts mainly at the level of ovary rather than on the pituitary gland. We suppose that in the natural environment cadmium present in the feed can play an important role in the accumulation of this element in fish tissues and can influence vital physiological processes.     

Effect of sewage on blood parameters and the resistance against bacterial infection of goldfish,Carassius auratus

Effects of raw and treated sewages on blood parameters and on the resistance against bacterial infection of goldfish (Carassius auratus) were investigated. All fish exposed to 50% raw and 100% treated sewages died within 3 days. Plasma ammonia and lactate increased after 3 days' exposure to 10% raw and 20% treated sewages, though no fish died within 30 days. On day 30, the numbers of red blood cells, granulocytes and lymphocytes, activity of phagocytic cells, Hb, and plasma protein showed lower values than those of the control. Similar changes in blood parameters were observed in goldfish exposed to 5% raw and 10% treated sewages for 30 days, though to a lesser extent. No changes in these parameters were found in fish exposed to 5% treated sewage, whereas higher values for chloride, manganese, and bromide, and lower values for potassium and zinc, were observed on day 30, compared to those of the control. Fish exposed to 5% treated sewage for 30 days prior to an intraperitoneal challenge with Aeromonas salmonicida showed decreased survival rates. These results suggest that fish exposed to sewage, even to 5% treated sewage, are subject to suppression of the immune response. © 1997 by John Wiley & Sons, Inc. Environ Toxicol Water Qual 12: 43–51, 1997     

Effects of ECF-Kraft pulp mill effluent treated with fungi (Rhizopus oryzae) on reproductive steroids and liver CYP1A of exposed goldfish (Carassius auratus)

The toxicity of bleached Kraft pulp mill effluents (BKME) is usually attributed to chemical compounds which are produced and released throughout various stages of pulp and paper production. The main objective of the present work was to detect sub-lethal responses of goldfish (Carassius auratus) to secondary treated BKME which was treated with Rhizopus oryzae. A total of 96 carps (C. auratus; 11 ± 3 g) were exposed to different concentrations of the post-treated effluent (0, 1, 10, 25, 50, and 100%), in 28 days semi-static tests. Several biomarkers were then evaluated to assess the toxicological effects: induction of CYP1A (metabolic processes of organic compounds in liver), change in steroid profiles (11-Ketotestosterone, 17β-estradiol), histopathology of liver and gonads and somatic indices (GSI, HSI) for endocrine disruption and other physiological disturbances. The most significant results show an induction of CYP1A in both sexes and a decrease of 17β-estradiol concentrations in females. Histopathological changes such as liver tissue degeneration were observed in fish exposed to 50 and 100% of the BKME. Although the BKME was biologically treated there are some chemical compounds in the effluent that are capable to affect fish physiology, however, a clear evidence for endocrine disruption was not found.     

Refuse leachate exposure causes changes of thyroid hormone level and related gene expression in female goldfish (Carassius auratus)

To elucidate the potential thyroid disrupting effects of refuse leachate on females, female goldfish (Carassius auratus) were exposed to 0.5% diluted leachates from each step of a leachate treatment process (i.e. raw leachate before treatment, after membrane bioreactor treatment, and the final treated leachate) for 21 days. Raw leachate exposure caused disturbances in the thyroid cascade of female fish, as evidenced by the elevated plasma 3,3ʹ,5-triiodo-l-thyronine (p < 0.05) and thyroid-stimulating hormone (p < 0.01) levels as well as up-regulated hepatic and gonadal type I deiodinase (p < 0.01), type II deiodinase (p < 0.01) and thyroid receptor (p < 0.05) mRNA levels. Thyroid disrupting potency decreased markedly as raw leachate progressed through the “membrane bioreactor + reverse osmosis” treatment but could still be detected in the treated leachate. As our results indicated, thyroid system in female goldfish was more sensitive to leachate exposure than that of the male fish.     

Molecular cloning of CYP1A gene and its expression by benzo(a)pyrene from goldfish (Carassius auratus)

We cloned and sequenced the cytochrome P450 1A (CYP1A) gene from goldfish (Carassius auratus). It has a 1581 bp open reading frame that encodes a 526 amino acid protein with a theoretical molecular weight of 59.02 kDa. The CYP1A amino acid sequence clusters in a monophyletic group with other fish CYP1As, and more closely related to zebrafish CYP1A (91% identity) than to other fish CYP1As. Exposure to benzo(a)pyrene (BaP) by intraperitoneal injection increased biliary BaP metabolites and liver CYP1A gene expression. BaP exposure also increased CYP1A gene expression in extrahepatic organs, including intestine, and gill, which are sensitive to aqueous and dietary exposure to Arylhydrocarbon receptor (AhR) agonists. Therefore, goldfish CYP1A identified in this study offers basic information for further research related to biomarker use of CYP1A of goldfish.     

Impairment of the mitochondrial oxidative phosphorylation system and oxidative stress in liver of crucian carp (Carassius auratus L.) exposed to microcystins

Hepatotoxic microcystins (MCs) are produced by cyanobacteria in diverse water bodies and the pathophysiology includes induction of reactive oxygen species and adenosine triphosphate (ATP) depletion in cells. In this study, we evaluated MCs induced changes in the oxidative phosphorylation (OXPHOS) system in mitochondria of crucian carp liver. Fish were subdivided into two groups that were intraperitoneally injected with two doses of MCs (50 and 200 MC‐LReq μg/kg bw) and were sacrificed at 1, 3, 12, 24, and 48 h postinjection. The activities of five enzyme complexes of electron transport chain and mRNA expression of mitochondrial‐encoded genes (cox1, cox2, cox3, and atp6) were significantly reduced in a time‐dependent pattern after injection. There were also changes in mitochondrial ultrastructure, decreases in ATPase activities and reduction in antioxidant level after MCs exposure. Disorder in the OXPHOS system and decreased activities of antioxidative enzymes might contribute to bioenergy deficiency and consequent hepatocyte damage induced by MCs. © 2011 Wiley Periodicals, Inc. Environ Toxicol 29: 30–39, 2014.     

Effects of beryllium metal particles on the viability and function of cultured rat alveolar macrophages

The physicochemical properties of particles influence their in vivo toxicity following deposition in the respiratory tract. To evaluate the relative contributions of mass and surface area to particle-induced toxicity, rat pulmonary alveolar macrophages (PAM) were exposed to four types of particles in vitro. We used three beryllium metal samples: relatively large (Be-II) and relatively small (Be-V) sized fractions of beryllium metal obtained from an aerosol cyclone, and a beryllium metal aerosol generated by laser vaporization of bulk beryllium metal in an argon atmosphere (Be-L). We also used glass beads (GB) as a negative control particle. End points examined included cell viability, determined by trypan blue dye exclusion, and changes in phagocytic ability, measured by counting the number of sheep red blood cells internalized by the PAM. Phagocytic ability was inhibited by exposure to beryllium particles at concentrations that did not cause appreciable cell death. Results describing effects based on the mass concentration of particles in culture medium were transformed by the amount of specific surface area of the particles to permit the expression of toxicity relative to the amount of particle surface per unit volume of culture medium. On a mass basis, the order of particle-related cytotoxicity was Be-L greater than Be-V greater than Be-II greater than GB, and for inhibition of phagocytosis, the order was Be-L approximately Be-V greater than Be-II greater than GB. When analyzed on a specific surface area basis, the cytotoxicity of the different materials became more similar in a fashion that was largely predicted by the amount of surface of the particles administered. However, because differences in specific surface area among the beryllium particle samples did not entirely predict cytotoxicity, we concluded that factors in addition to specific surface area influenced the expression of toxic effects in cultures of PAM exposed to beryllium metal.     

Effects of dopaminergic drugs on the mast cell degranulation and nitric oxide generation in RAW 264.7 cells

Effects of dopaminergic drugs on the degranulation of mast cells (RBL-2H3 cells) and the nitric oxide production from macrophage cells (RAW 264.7) were studied. Among the dopaminergic agonists and antagonists tested, bromocriptine, 7-OH-DPAT, haloperidol, and clozapine showed potent inhibitions of mast cell degranualtion (IC50 value, 5 microM). However, these dopaminergic agents did not affect the tyrosine phosphorylations of the signaling components of the high affinity IgE receptor (FcepsilonRI), such as Syk, PLCgamma1, and PLCgamma2.; This suggested that these signaling components were not involved in the inhibition of the mast cell degranulation by these compounds. On the other hand, dopamine, bromocriptine, 7-OH-DAPT, and haloperidol markedly inhibited the nitric oxide production from RAW 264.7 cells (IC50 values, 10-20 microM). Bromocriptine, a dopamine agonist that is routinely used for the treatment of Parkinsons disease, inhibited the expression of the inducible nitric oxide synthase at an early stage of the LPS-induced protein expression in a dose-dependent manner. The results suggested that these dopaminergic agents, when used for the treatment of dopamine receptors-related diseases, such as Schizophrenia or Parkinsons disease, might have additional beneficial effects.     

Effects of antimicrobial metal nanoparticles on characteristics and function properties of mouse mesenchymal stem cells

Nanoparticles (NPs) have a wide use in various field of industry and in medicine, where they represent a promise for their antimicrobial effects. Simultaneous application of NPs and therapeutic stem cells can speed up tissue regeneration and improve healing process but there is a danger of negative impacts of NPs on stem cells. Therefore, we tested effects of four types of metal antimicrobial NPs on characteristics and function properties of mouse mesenchymal stem cells (MSCs) in vitro. All types of tested NPs, i.e. zinc oxide, silver, copper oxide and titanium dioxide, exerted negative effects on the expression of phenotypic markers, metabolic activity, differentiation potential, expression of genes for immunoregulatory molecules and on production of cytokines and growth factors by MSCs. However, there were apparent differences in the impact of individual types of NPs on tested characteristics and function properties of MSCs. The results showed that individual types of NPs influence the activity of MSCs, and thus the use of metal NPs during tissue regeneration and in combination with stem cell therapy should be well considered.     

Effects of essential oil extracted from Nigella sativa (L.) seeds and its main components on human neutrophil elastase activity

The effects of essential oil extracted from Nigella sativa (L.) seeds and its main components on human neutrophil elastase (HNE) activity were investigated. Essential oil was extracted from N. sativa (L.) seeds using hydrodistillation. The yield was equal to 0.4%. Inhibition of HNE activity by essential oil was found to be dose dependent. The highest inhibitory concentration (HIC) of essential oil which caused total inhibition of HNE activity was 5.8 mg/ml. Microassays carried out to evaluate the inhibitory effect of major components of essential oil on HNE activity revealed that carvacrol (5-isopropyl-2-methylphenol) showed marked HNE inhibitory activity with a very low IC(50) value (12 microM). Based on these results, the inhibitory effects of essential oil on HNE activity are due to the presence of bioactive molecules, mainly carvacrol this compound is an inhibitor of HNE and could be considered as a natural antielastase agent and possible candidate for phytotherapy in the treatment of injuries that appear in some pathologic cases such as chronic obstructive pulmonary disease and emphysema.     

Antinociceptive and anti-inflammatory effects of olive oil (Olea europeae L.) in mice

Context: Olive [Olea europaea L. (Oleaceae)] is a long-lived evergreen tree that is widespread in different parts of the world.

Objective: Olive oil has been reported to relieve pain; however, there is still insufficient data in the literature on the subject. Thus, it is considered worthwhile investigating the antinociceptive and anti-inflammatory effects of olive oil in adult male Balb/C mice.

Materials and methods: The antinociceptive effects were studied using formalin, hot plate and writhing tests. The acute anti-inflammatory effects of olive oil in mice were studied using xylene ear edema test. Olive oil (1, 5 and 10?ml/kg body wt.) was injected intraperitoneally. Intact animals served as controls.

Results: Our results showed that the olive oil only decreased the second phase of formalin-induced pain. In the hot plate test, olive oil did not raise the pain threshold over the 60?min duration of the test. Olive oil exhibited antinociceptive activity against writhing-induced pain by acetic acid. In the xylene ear edema test, olive oil showed significant anti-inflammatory activity in the mice.

Discussion and conclusion: The present data indicated that olive oil has antinociceptive and anti-inflammatory effects in mice but further investigation of these effects is required to elucidate the mechanism(s) involved in analgesic and anti-inflammatory effects of Olea europaea oil.