Effects of copper and its ethylenediaminetetraacetate complex on the antioxidant defenses of the goldfish, Carassius auratus

Copper bioavailability in the tissues of goldfish and antioxidant defenses in the liver of fish were investigated in vivo following 40 days of exposure to different species of copper solutions at different concentrations. Copper seemed to be more concentrated in the gill than in the liver after Cu(2+) and copper-ethylenediaminetetraacetate (Cu-EDTA) exposure. The addition of EDTA markedly affected copper adsorption in the gill but had no significant effects in the liver. We also found that in the fish exposed to the concentration of Cu(2+) below the Chinese national fishery water quality standard of 0.01 mg/L, superoxide dismutase (SOD) and glutathione S-transferase (GST) activities in liver were stimulated and catalase (CAT) and Se-dependent glutathione peroxidase (Se-GPx) activities were inhibited after 40 days of exposure. Compared to copper exposure, the addition of EDTA did not affect SOD and GST significantly. However, CAT and GPx activity with Cu(2+) exposure were significantly different from those with Cu-EDTA exposure.     

Oxidative stress biomarkers of exposure in the blood of cichlid species from a metal-contaminated river

The oxidative stress biomarkers of exposure, such as reduced glutathione (GSH), activity of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) and the levels of lipid peroxidation (LPO), were measured in the blood of three cichlid fish (Oreochromis niloticus, Tilapia rendalli, and Geophagus brasiliensis) taken during two seasons from two sites, unpolluted and polluted by industrial effluents, to evaluate the effectiveness of these biomarkers in assessing the impact of water contamination. The LPO levels in the blood were higher in fish from the metal-contaminated site and the chronic exposure led to significant changes in GPx, CAT, and SOD activities in all three cichlid species. The considerable variation of responses in these cichlids to water contamination evidenced differences in sensitivity to the metal contamination and/or in the potential to respond to it highlighting the importance of using a set of related biomarkers to assess the impact of water contamination.     

Toxicity of the herbicide atrazine: effects on lipid peroxidation and activities of antioxidant enzymes in the freshwater fish Channa punctatus (Bloch)

The present study was undertaken to evaluate the toxicity and effects of a commercial formulation of the herbicide atrazine (Rasayanzine) on lipid peroxidation and antioxidant enzyme system in the freshwater air breathing fish Channa punctatus. The 12, 24, 48, 72 and 96 h LC(50) of atrazine, calculated by probit analysis, were determined to be 77.091, 64.053, 49.100, 44.412 and 42.381 mg·L(-1), respectively, in a semi static system with significant difference (p < 0.05) in LC(10-90) values obtained for different times of exposure. In addition to concentration and time dependent decrease in mortality rate, stress signs in the form of behavioral changes were also observed in response to the test chemical. In fish exposed for 15 days to different sublethal concentrations of the herbicide (1/4 LC(50) = ～10.600 mg·L(-1), 1/8 LC(50) = ～5.300 mg·L(-1) and 1/10 LC(50) = ～4.238 mg·L(-1)) induction of oxidative stress in the liver was evidence by increased lipid peroxidation levels. The antioxidants superoxide dismutase (SOD), catalase (CAT) and glutathione reductase (GR) responded positively in a concentration dependent pattern, thus, suggesting the use of these antioxidants as potential biomarkers of toxicity associated with contaminations exposure in freshwater fishes.     

Biomarkers signal contaminant effects on the organs of English sole (Parophrys vetulus) from Puget Sound

Fish living in contaminated environments accumulate toxic chemicals in their tissues. Biomarkers are needed to identify the resulting health effects, particularly focusing on early changes at a subcellular level. We used a suite of complementary biomarkers to signal contaminant-induced changes in the DNA structure and cellular physiology of the livers and gills of English sole (Parophrys vetulus) . These sediment-dwelling fish were obtained from the industrialized lower Duwamish River (DR) in Seattle, Washington, and from Quartermaster Harbor (QMH) , a relatively clean reference site in south Puget Sound. Fourier transform-infrared (FT-IR) spectroscopy, liquid chromatography/mass spectrometry (LC/MS) , and gas chromatography/mass spectrometry (GC/MS) identified potentially deleterious alterations in the DNA structure of the DR fish livers and gills, compared with the QMH fish. Expression of CYP1A (a member of the cytochrome P450 multigene family of enzymes) signaled changes in the liver associated with the oxidation of organic xenobiotics, as previously found with the gill. The FT-IR models demonstrated that the liver DNA of the DR fish had a unique structure likely arising from exposure to environmental chemicals. Analysis by LC/MS and GC/MS showed higher concentrations of DNA base lesions in the liver DNA of the DR fish, suggesting that these base modifications contributed to this discrete DNA structure. A comparable analysis by LC/MS and GC/MS of base modifications provided similar results with the gill. The biomarkers described are highly promising for identifying contaminant-induced stresses in fish populations from polluted and reference sites and, in addition, for monitoring the progress of remedial actions.     

Suppression of Endogenous Antioxidant Enzymes by 2,3,7,8-Tetrachlorodibenzo-<Emphasis Type="Italic">p</Emphasis>-dioxin–Induced Oxidative Stress in Chicken Liver During Development

Domestic chickens (Gallus gallus) are an excellent model in which to evaluate developmental toxicity and oxidative stress because of their high sensitivity to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). The goal of this study was to measure the effects of environmentally relevant doses of TCDD on endogenous hepatic antioxidant enzyme activity in hatchling chickens. The vehicle (sunflower oil) or 2, 20, or 200 pg/g TCDD was injected into chicken eggs before incubation. On hatching, livers were harvested and quickly frozen. The changes in activity of antioxidant enzymes, including glutathione peroxidase (GPx), glutathione reductase (GRx), copper zinc superoxide dismutase (SOD), and catalase (CAT) were determined as indicators of oxidative stress. TCDD exposure was associated with a significant suppression of the activities of the protective endogenous enzymes GPx, GRx, and SOD in the liver, even at the lowest dose. CAT activity was also suppressed, but not significantly. The measured decreases were 37% to 63% for GPx, 50% to 58% for GRx, 30% to 40% for SOD, and 16% to 24% for CAT. Noncomplex dose–response relationships were evident in GPx and GRx, whereas SOD and CAT curves were U-shaped. These results demonstrate that a decreased ability to scavenge reactive oxygen species may result from developmental TCDD exposure at very low doses, contributing to oxidative stress and thus to the embryotoxicity of TCDD.     

Acute toxicity of carbamazepine to juvenile rainbow trout (Oncorhynchus mykiss): effects on antioxidant responses, hematological parameters and hepatic EROD

Awareness of residual pharmaceutically active compounds (PhACs) in the aquatic environment is growing as investigations into these pollutants are increasing and analytical detection techniques are improving. However, the toxicological effects of PhACs have not been adequately researched. In this study, the toxic effects of carbamazepine (CBZ), an anticonvulsant drug commonly present in surface and groundwater, was studied in juvenile rainbow trout, Oncorhynchus mykiss, by acute semi-static bioassay. Bood parameters, liver xenobiotic-metabolizing response and tissue antioxidant status were evaluated. Compared to the control group, fish exposed to CBZ (96 h LC50) showed significantly higher Er, Hb, MCHC, monocytes, neutrophil granulocytes and plasma enzymes activity, and significantly lower MCV and lymphocytes. CF and HSI were not significantly different among groups such as hepatic EROD. SOD, CAT, GPx and GR activity was significantly higher in liver of experimental groups, but decreased significantly in brain and gill. In general, antioxidant enzyme activity in intestine and muscle was less evident than in liver. Oxidative stress indices (levels of LPO and CP) were significantly higher in gill and brain, despite a trend to increased values were manifested in the remaining tissues. In short, CBZ-induced stress responses in different tissues were reflected in the oxidant stress indices and hematological parameters. However, before those parameters are used as special biomarkers for monitoring residual pharmaceuticals in aquatic environment, more detailed experiments in laboratory need to be performed in the future.     

The use of learning computers in the general educational system: hygienic aspects

The use of learning computers (LCs) in a present-day academic process poses for hygienists and physiologists new problems, such as to evaluate the influence of LCs on schoolchildren's health and to substantiate and to develop the ways of drawing up and presenting the materials in terms of their readability and regulation of learning regimens. Analysis of the currently available LCs has established the factors contributing to the accelerated development of visual and overall fatigue, its accumulation: the brightness characteristics of electronic pages, including both the violation of the allowable brightness levels and the irregularity of intensity distribution; a significant inadequacy of type sizes; a great variety of lettering and coloring. The recent LCs for general education are the visual aggressive medium for schoolchildren, which is certain to require their hygienic evaluation on the basis of specially developed hygienic requirements for LCs.     

Testicular Oxidative Stress and Cellular Deformities in <Emphasis Type="Italic">Clarias gariepinus</Emphasis> (Burchell) from River Yamuna in Delhi Region,India

River Yamuna is under constant menace due to pollution levels beyond limit, ensuing chronic poisoning of aquatic biota. Induction of oxidative stress and cellular deformities is a common effect in fish. The present study aimed in assessing impact of environmental pollutants on gonad (testis) of Clarias gariepinus from Wazirabad barrage (entry site) and Okhla barrage (exit site) of river Yamuna in Delhi segment. Antioxidant enzymes assays viz. Super oxide dismutase (SOD), catalase (CAT) and ferric reducing antioxidant power (FRAP); thiobarbituric acid reactive substance assay (TBARS) for determining level of lipid peroxidation and histology for analysis of degenerative changes were employed as biomarkers. The results depicted signs of environmental contamination, hallmarked by significant increase (p?<?0.001) in TBARs level (µmol/g wet tissue); significant decrease (p?<?0.001) in SOD, CAT (U/mg protein) and FRAP value (U/mg tissue) in response to greater pollution at Okhla barrage as compared to Wazirabad barrage. Degenerative changes viz. unorganized seminiferous tubules, extensive vacuolization in germ cells, inflammatory lesions, greater vacant spaces and condensation of tubular cells prevailed in 75%, 85%, 80%, 80%, and 65% specimens respectively from Okhla barrage. Hence, the selected biomarkers highlighted the existence of greater prooxidative compounds at the exit site resulting in stressful condition for fish in river basin.     

Induction of oxidative stress by arsenic in Clarias batrachus: involvement of peroxisomes

Indian catfish, Clarias batrachus, were exposed to two nonlethal doses of arsenic for 10 days, which induced tissue lipid peroxidation, increased the ratio of oxidized to reduced glutathione and produced excess H(2)O(2) within 1-2 days of exposure. Furthermore, arsenic treatment increased the activity of antioxidant enzymes such as glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase but decreased glutathione reductase (GR) activity within a day of exposure, indicating the generation of oxidative stress in fish at an early stage. Reversibility of these arsenic-induced responses by pretreatment with N-acetylcysteine indicates that the oxidative stress was due to excess H(2)O(2) production, which was found to be partially contributed by altered H(2)O(2) metabolism in the peroxisomes. It is therefore concluded that peroxisomal H(2)O(2) metabolizing enzymes are potential targets of arsenic toxicity in C. batrachus.     

Vitamin E and L-carnitine, separately or in combination, in the prevention of radiation-induced oral mucositis and myelosuppression: a controlled study in a rat model

The aim of this study was to determine the effects of vitamin E (VE) and L-carnitine (LC) supplementation, separately or in combination, on radiation-induced oral mucositis and myelosuppression. Group 1 received no treatment (control). Group 2 received 15 Gray of 60Co gamma irradiation as a single dose to total cranium (IR). Group 3, 4, and 5 received irradiation plus 40 mg/kg/day VE (IR+VE) or 200 mg/kg/day LC (IR+LC) or in combination (IR+VE+LC) respectively. Clinically and histopathologically, assessments of mucosal reactions were performed by two independent experts in Radiation Oncology and Pathology, respectively. Hematologic analyses and antioxidant enzyme evaluations were also performed. Irradiation significantly increased oral mucositis, and decreased thrombocyte and White Blood Cell counts. A significant increase in malondialdehyde (MDA) levels and decrease in superoxide dismutase (SOD) and catalase (CAT) activities in plasma were found in the IR group. VE and LC administration, separately, plus irradiation significantly delayed the starting day, and reduced the severity of, oral mucositis. This administration also reduced a fall in the numbers of thrombocyte and WBC caused by irradiation, and decreased the MDA level, and increased the activity of SOD and CAT enzymes in the plasma. VE and LC, in combination, plus irradiation did not provide a superior radioprotection against radiation-induced toxicities.     

Effects of Water Cadmium Concentrations on Bioaccumulation and Various Oxidative Stress Parameters in <Emphasis Type="Italic">Rhamdia quelen</Emphasis>

The effects of sublethal cadmium concentrations on oxidative stress parameters were evaluated in Rhamdia quelen. The fish were exposed to 0.44, 236, and 414 μg l⁻¹ cadmium for 7 and 14 days, followed by the same time periods for recovery. Enzymes, such as catalase (CAT), superoxide dismutase (SOD), and glutathione S-transferase (GST), and indicators of oxidative stress, such as thiobarbituric acid-reactive species (TBARS) and protein carbonyl, were verified in fish tissues. In addition, the accumulation of cadmium was evaluated in these tissues. Our results indicate that CAT and GST levels decreased in gills after exposure periods associated with increased TBARS levels. In hepatic tissue, CAT, GST, TBARS, and protein carbonyl levels increased after 7 days of exposure, whereas SOD activity decreased after exposure for 14 days. In the kidney, TBARS levels decreased after exposure for 7 days and increased after exposure for 14 days. During the recovery periods, some variations persisted in gills, liver, and kidney. Cadmium accumulation was most significant in liver, followed by kidney and gills. These results indicate that cadmium concentrations studied invoke a stress response in silver catfish.     

低剂量辐射对荷瘤鼠放疗后血清中抗氧化酶活性的影响

目的 观察低剂量辐射对荷瘤鼠放疗后血清中抗氧化酶活性的影响。方法 采用化学比色法测定不同照射时相点血清中超氧化物歧化酶(SOD)、谷胱甘肽-S转移酶(GST)和过氧化氢酶(CAT)活性。结果 低剂量全身照射组血清中SOD、GST、CAT活力高于相应对照组;低剂量+局部放疗组(d₃ d₅)血清中SOD、GST、CAT活力显著高于局部大剂量组(c₃,c₅);尤以连续三天照射组明显。结论 低剂量辐射激活荷瘤机体抗氧化物酶可能是低剂量辐射抑瘤作用的部分机制     

Oxidative stress response in an endangered goodeid fish (Girardinichthys viviparus) by exposure to water from its extant localities

The oxidative stress response in Girardinichthys viviparus after exposure to water from its extant habitants was evaluated. The distribution range of this endangered species is currently restricted to a single lake, which receives domestic and industrial wastewater treated to a secondary level, but this is also contaminated with PCBs. Fish were exposed to water from Lake Texcoco, its extant habitat or another one, the Lake Zumpango proposed as a candidate to re-introduction. To predict the damage induced by sublethal increases in PCBs, assessment is also made of fish response to water from these localities enriched with PCB mixtures. Adult fish born in the laboratory were exposed to filtered surface water or to the PCB-enriched water for 1, 2, 4, 8 and 16 days. An assessment of the oxidative stress response in G. viviparus revealed four characteristic response patterns that were frequently observed: (1) increased lipid-peroxidation (LPOX), depressed SOD and increased CAT; (2) an increase in all three biomarkers; (3) reduced LPOX, unchanged SOD and increased CAT; (4) increased LPOX and depressed SOD and CAT. Our results demonstrate the complexity stress response of this endangered species while indicating that preventive measures are urgent to control the discharge of pro-oxidants in its environment.     

Responses of Oxidative Stress Biomarkers and DNA Damage on a Freshwater Snail (Bellamya aeruginosa) Stressed by Ethylbenzene

Ethylbenzene is classified as a priority pollutant; however, toxicity data, especially those regarding sublethal toxicity, are rarely reported on gastropods. The present work was performed to elucidate the sublethal effects of ethylbenzene using a freshwater snail, Bellamya aeruginosa (Reeve), exposed to ethylbenzene for 21 days followed by a 17-day recovery period. Superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST), reduced glutathione (GSH), and malonyldialdehyde (MDA) were used as biomarkers to evaluate oxidative stress in hepatopancreas of snails. In addition, alkaline comet assay was applied to determine the genotoxicity of ethylbenzene in hepatopancreas of snails. These biomarkers and DNA damage exhibited various responses to ethylbenzene in the tested snails. SOD and CAT activities were almost significantly stimulated during the exposure period. As exposure time was prolonged beyond 7 days, CAT activity gradually became significantly increased at higher doses of ethylbenzene. GSH concentration was positively and linearly related with exposure dose. MDA concentration was significantly greater than that in the control only under the lowest treatment after a 7-day exposure. Alkaline comet assay showed that ethylbenzene could significantly induce DNA damage in hepatopancreas of snails, and there was a good dose- and time-response in DNA damage, indicating potential genotoxicity of ethylbenzene on snails. At the end of the recovery period, the repair of DNA damage was not yet completed, showing that DNA repair requires more time. The findings from this study could indicate that SOD, GST, and GSH seem to be effective oxidative biomarkers for snails exposed to ethylbenzene in the short term. CAT proved to be a valuable discriminating biomarker in subchronic exposure to ethylbenzene, but MDA was not a suitable oxidative biomarker for exposure to ethylbenzene in either the short or long term. Alkaline comet assay was efficient tool with which to evaluate the potential genotoxicity of ethylbenzene.     

Occurrence,Distribution and Ecological Risks of Fluoroquinolone Antibiotics in the Dongjiang River and the Beijiang River,Pearl River Delta,South China

In this study, sublethal effects on the Mediterranean mussels (Mytilus galloprovincialis L.) collected from the Aegean coast of Turkey were determined. Enzymes such as glutathione-S-transferase (GST), superoxide dismutase (SOD), catalase (CAT), and acetylcholinesterase (AChE), metallothionein (MT) mRNA expressions, thiobarbituric acid reactive substances (TBARS) contents, determination of 14 heavy metals and micronucleus frequency were selected as multibiomarkers. Results show that heavy metals and an increase in the level of MT gene expression have been determined in tissues of mussels collected from all stations. The GST, SOD and CAT enzymes were increased in mussels of Aliaga and Old Foca, compared to the mussels of Urla, while it was showed inhibition at AChE levels. Extensive LP is determined on mussels of Aliaga. It was determined that mussels in Aliaga region have exposed more oxidative stress than Old Foca and Urla. These biomarkers were carried out for the first time in these stations to assess environmental quality.     

Accumulation and Elimination of Cadmium by the Nile Tilapia (Oreochromis niloticus) in differing Temperatures and Responses of Oxidative Stress Biomarkers

The aims of this study were to investigate the accumulation (15 days) and elimination (15 and 30 days) of cadmium (Cd) in the liver, gill, kidney and muscle of Oreochromis niloticus following exposures to different concentrations (1 and 2 mg/L) of Cd at different water temperatures (20, 25, 30 ^oC). Additionally, responses of oxidative stress biomarkers (superoxide dismutase, SOD; catalase CAT; glutathione peroxidase, GPx and malondialdehyde, MDA) of the liver were determined following Cd exposures. In accumulation period, Cd levels increased significantly in all the tissues at all temperatures and tissue accumulation order was kidney?>?liver?>?gill. All tissues, except the muscle, accumulated Cd in relation to exposure concentrations and water temperatures. There was no measurable level of Cd accumulation in the muscle, except in fish exposed to 2 mg Cd/L at 30 ^oC. Likewise, elimination of Cd from the tissues also increased in depends on periods and water temperatures. The order of Cd elimination from the tissues was gill?>?liver?>?kidney. The oxidative stress biomarkers also responded to both Cd exposure and temperature increases. The activities of antioxidant enzymes such as SOD, CAT, GPx and MDA levels in the liver increased in relation to increases in Cd concentrations and water temperatures.

     

The effect of supplementation with omega-3 polyunsaturated fatty acids on markers of oxidative stress in elderly exposed to PM(2.5)

BACKGROUND: The mechanisms of particulate matter (PM)-induced health effects are believed to involve inflammation and oxidative stress. Increased intake of omega-3 polyunsaturated fatty acids (n-3 PUFA) appears to have anti-inflammatory effects. OBJECTIVE: As part of a trial to evaluate whether n-3 PUFA supplementation could protect against the cardiac alterations linked to PM exposure, we measured biomarkers of response to oxidative stimuli [copper/zinc (Cu/Zn) superoxide dismutase (SOD) activity, lipoperoxidation (LPO) products, and reduced glutathione (GSH)] and evaluated the impact of supplementation on plasma levels. METHODS: We recruited residents from a nursing home in Mexico City chronically exposed to PM < or = 2.5 microm in aerodynamic diameter (PM(2.5)) and followed them from 26 September 2001 to 10 April 2002. We randomly assigned subjects in a double-blind fashion to receive either fish oil (n-3 PUFA) or soy oil. We measured PM(2.5) levels indoors at the nursing home, and measured Cu/Zn SOD activity, LPO products, and GSH at different times during presupplementation and supplementation phases. RESULTS: Supplementation with either fish or soy oil was related to an increase of Cu/Zn SOD activity and an increase in GSH plasma levels, whereas exposure to indoor PM(2.5) levels was related to a decrease in Cu/Zn SOD activity and GSH plasma levels. CONCLUSION: Supplementation with n-3 PUFA appeared to modulate the adverse effects of PM(2.5) on these biomarkers, particularly in the fish oil group. Supplementation with n-3 PUFA could modulate oxidative response to PM(2.5) exposure.     

Peroxidation in muscle and liver tissues from fish in a contaminated river due to a petroleum refinery industry

In this study, we aimed to investigate the possible effects of the wastewater water contamination of a petroleum industry on the oxidant/antioxidant status of muscle and liver tissues from fish in the Kizilirmak River, Kirikkale, Turkey. The antioxidant/oxidant parameters were analyzed in the muscle and liver tissues from fish in 10 km of the river above and below the industry. Malondialdehyde (MDA) and susceptibility to oxidation (SO) values were measured in the liver and muscle tissues as indexes of oxidation, and antioxidant potential (AOP), superoxide dismutase (SOD), glutathion peroxidase (GSH-Px), and catalase(CAT) activities were measured as indexes of antioxidant status. There was significant oxidation in the muscle tissue of the fish obtained in the river downstream of the industry compared to those obtained upstream of the industry. Although there were no meaningful differences between the SOD and GSH-Px activities, the AOP value and CAT activities were found to be reduced in the muscle tissues from the fish obtained downstream. In the liver tissues, the SOD and GSH-Px activities were found to be increased in the fish obtained downstream but no differences were observed in the MDA, SO, AOP, and CAT values. Our results suggest that some contaminants from the petrochemical industry cause oxidation in fish muscle tissues by impairing the antioxidant system. However, because no peroxidation was observed in the liver tissue from the downstream fish, it is possible that liver tissues have a stronger antioxidant capacity than muscle.     

三氯乙烯对职业接触人群脂质过氧化作用

目的 探讨三氯乙烯（trichloroethylene，TCE）对职业接触人群外周血脂质过氧化作用的影响。方法采集207名直接接触TCE工人的班末尿和外周肘静脉血，分析尿中三氯乙烯（Trichloroactic acid，TCA）含量，测定外周血过氧化氢酶（CAT）、超氧化物歧化酶（SOD）、谷胱甘肽过氧化物酶（GSH-PX）、丙二醛（MDA）的活性或含量。结果接触组工人红细胞CAT、血清总SOD和GSH-PX活性以及血清中脂质过氧化产物MDA含量均呈现升高趋势，CAT、总SOD与接触TCE的工龄，以及CAT、总SOD、GSH-PX与接触剂量间均呈显著的抛物线性关系，MDA与接触工龄及接触剂毋间均呈直线关系。结论TCE可引起职业接触人群脂质过氧化水平增高。脂质过氧化指标可作为早期职业接触损伤的生物效应指标之一。CAT可作为早期、敏感的生物效应监测指标。