Morphological and biochemical perturbations in rat erythrocytes following in vitro exposure to Fenvalerate and its metabolite

Maternal exposure to deltamethrin during pregnancy and lactation impairs neurodevelopment of male offspring

Deltamethrin (DM) is a highly effective and widely used pyrethroid pesticide. It is an environmental factor affecting public and occupational health and exerts direct toxic effects on the central nervous system. As the major target organs for neurotoxicity of DM, the hippocampus and the cerebellum are critical to the learning and motor function. Pregnant Wistar rats were randomly divided into four groups and gavaged at doses of 0, 1, 4or 10 mg/kg/d DM from gestational day (GD) 0 to postnatal day (PN) 21. The PC12 cells were selected to further verify the regulatory mechanisms of DM on the neurodevelopmental injury. We found that maternal exposure to DM caused learning, memory and motor dysfunction in male offspring. Maternal exposure to DM induced the decrease in the density of hippocampal dendritic spines in male offspring through the reduced expression of M1 mAchRs, which in turn reduced the mediated AKT/mTOR signaling pathway, contributing to the inhibition of dynamic changes of GluA1. Meanwhile, DM exposure inhibited the BDNF/TrkB signaling pathway, thereby reducing phosphorylation of stathmin and impairing cerebellar purkinje cell dendrite growth and development. Taken together, maternal exposure to DM during pregnancy and lactation could impair neurodevelopment of male offspring.

Curcumin-loaded chitosan nanoparticles alleviate fenpropathrin-induced hepatotoxicity by regulating lipogenesis and pyroptosis in rats

In this study, the probable alleviative role of curcumin (CMN) (50 mg/kg b.wt) or curcumin-loaded chitosan nanoparticle (CLC-NP) (50 mg/kg b.wt) was assessed against the hepatotoxic effect of a widely used pyrethroid insecticide, fenpropathrin (FEN) (15 mg/kg b.wt) in rats in a 60-day experiment. The results revealed that CMN and CLC-NP significantly suppressed the FEN-induced increment in serum hepatic enzyme activities (ALT, AST, and ALP) and hyperbilirubinemia. Moreover, FEN-associated dyslipidemia, hepatic oxidative stress, and altered hepatic histology were significantly rescued by CMN and CLC-NP. Furthermore, the increased TNF-α and Caspase-3 immunoexpression in hepatic tissues of FEN-exposed rats was significantly reduced in CMN and CLC-NP-treated ones. FEN exposure significantly upregulated the pyroptosis-related genes, including GSDMD, Casp-1, Casp-3, Casp-8, IL-18, TNF-α, IL-1β, and NF-κB and altered the expression of lipogenesis-related genes including SREBP-1c, PPAR-α, MCP1, and FAS in the hepatic tissues. Nevertheless, the earlier disturbances in gene expression were corrected in CMN and CLC-NP-treated groups. Of note, compared to CMN, CLC-NP was more effective at inhibiting oxidative damage and controlling lipogenesis and pyroptosis in the hepatic tissues of FEN-exposed rats. Conclusively, the current study findings proved the superior and useful role of CLC-NP in combating pollutants associated with hepatic dysfunction.

β-Cyfluthrin-Mediated Cytotoxicity of Cultured Rat Primary Hepatocytes Ameliorated by Cotreatment with Luteolin

The current study was designed to evaluate the possible protective effects of luteolin against β-cyfluthrin-mediated toxicity on the primary culture of rat hepatocytes (RHs). In the first step, the exposure of RHs to β-cyfluthrin (10, 20, 40, and 80 μM) was assessed by MTT. Second, redox condition was evaluated in cotreatment of cells with luteolin (20, 40, and 60 μM) and β-cyfluthrin (40 μM) at both medium and intra levels. In comparison to control, viability was lower in 40 and 80 μM β-cyfluthrin-treated groups at 24 h and all β-cyfluthrin-treated groups at 48 h (P < 0.05). Cotreatment with 20 or 40 μM luteolin + 40 μM β-cyfluthrin resulted in a higher viability value compared to β-cyfluthrin alone at 24 and 48 h of incubation (P < 0.05). Administration of 20 or 40 μM luteolin with β-cyfluthrin led to the decrease of malondialdehyde and total nitrate/nitrite and the increase of total antioxidant capacity (TAC) values in both medium and intrahepatocyte levels compared to the β-cyfluthrin-treated group at 48 h (P < 0.05). It seems that low and medium doses of luteolin possess the potential to reduce β-cyfluthrin-mediated hepatotoxicity via attenuation of peroxidative/nitrosative reactions and augmentation of TAC levels.

Ocimum basilicum Essential Oil Modulates Hematotoxicity, Oxidative Stress, DNA Damage, and Cell Cycle Arrest Induced by β-cyfluthrin in Rat Liver

Pesticides are used in large quantities infrequently, resulting in environmental damage and health issues. The goal of the current study was to explore the ameliorating effect of Ocimum basilicum (Basil) leaves essential oil versus the harmful effects of β-cyfluthrin in rat liver. Male Wistar rats were classified at random into four groups; negative control (corn oil), basil leaves essential oil (BEO, 3 ml/kg), β-cyfluthrin (positive control) (β-Cyf; 15 mg/kg BW, 1/25 LD50), and BEO plus β-Cyf, respectively. The rats were given their doses orally every day for a month. Results revealed that BEO yielded 6.32 mg/g with 33 identified components, representing 97% of the total oil. BEO implicated a considerable level of total phenolic contents, DPPH radical scavenging capacity, ABTS activity, and FRAP. The treatment of β-Cyf dramatically elevated lipid peroxidation (TBARS and H2O2) (LPO), protein oxidation (PC, AOPP, and HYP), and considerably reduced enzymatic (SOD, CAT, GPx, GR, and GST) and non-enzymatic (GSH) antioxidants. After β-Cyf treatment, hematological parameters, body and liver weights, enzyme activity (AST, ALT, ALP, and LDH), as well as protein, albumin, globulin, and total bilirubin levels were all considerably affected. Furthermore, β-Cyf increased the expression of pro-inflammatory genes (TNF-α, IL-6) as well as DNA damage and cell cycle arrest in the G0/G1 phase and decreased the number of cells in S and G2/M phase of liver cells. Moreover, rats given BEO then intoxicated with β-Cyf showed substantial changes in the majority of the parameters tested. Finally, BEO was shown to have high antioxidant efficacy in combating β-Cyf toxicity because of its high phenolic content.

Ameliorating effect of ascorbic acid on fenvalerate induced ultrastructural changes in scales, erythrocytes and gills of Ctenopharyngodon idella (Valenciennes, 1844)

Fenvalerate (type II synthetic pyrethroid), widely used in agricultural practices, find its way into aquatic ecosystem through air, by runoff, or by percolation to groundwater. It is an extremely toxic insecticide for aquatic organisms especially fish. In the present study, the fenvalerate (FEN) induced toxicity and the protective efficacy of ascorbic acid (AA) against FEN in Ctenopharyngodon idella was evaluated by studying the structural alterations in scales, erythrocytes and gills. The fishes were exposed to 1.2 μg/L and 2 μg/L of FEN and orally administered with 1000 mg/kg diet of AA. The fishes were scrutinized on 15^th, 30^th and 60^th day of experiment. Scanning electron microscopic studies (SEM) of FEN-treated fish revealed extensive morphological alterations on the microstructure of scales including deformed focus, uprooted lepidonts and tubercles, hole formation and worn out calcareous material from the surface. FEN intoxication induced severe damage on erythrocytes including formation of dacrocytes, serrated spherocytes, echinocytes with oozed out cytoplasmic content, contracted plasma membrane and appearance of lobopodial projections. Ultrastructural studies in gills declared profound lesions in the form of aneurysm, loss of secondary lamellae and destructed microstructures of pavement cells. On the other hand, supplementation of AA in diet mitigated the impairment provoked by FEN on the scales, erythrocytes and gills due to its antioxidant properties.

Toxicity assessment of chronic exposure to common insecticides and bee medications on colony development and drones sperm parameters

The effect of agrochemicals and beekeeping treatments on drones have not been widely investigated compared to workers or queens. In the present study, we investigated the chronic exposure of chemicals set (deltamethrin, acetamiprid, oxalic acid, fumagillin, and amitraz) on some sperm parameters and on the histomorphology of seminal vesicles. We also assessed the colony development and nosema load before and after the exposure. Thirty native Apis mellifera anatolica honeybee colonies with sister queens equalized with brood and total frame of bees were used for this experiment. Five colonies were used for each group. Deltamethrin, acetamiprid and fumagillin were given as oral chronic exposure at final concentrations of 25.10^-6 mg L^-1, 0.01 m L^-1 and 50 mg L^-1 respectively in syrup solution (50/50). Colonies were exposed to oxalic acid by spraying 5 mL per frame space of 3% (w/v) of oxalic acid dihydrate. Finally, the amitraz was applied based on the manufacturer's instructions. The concentrations chosen represented the field-realistic concentrations and those used by beekeepers in the region. Results showed that deltamethrin reduced brood production. In the same group, we found a high increase in nosema load. All treatments decreased sperm count except for fumagillin but this compound increased sperm mortality and increased the percentage of sperm with defected acrosome integrity. The amitraz exhibited a high sperm mortality and high percentage of sperm with defected membrane integrity function. The sperm parameters such as the count, the motility, the acrosome integrity, the membrane function of sperm, and the histomorphology of seminal vesicles of drones exposed to oxalic acid were the most affected. Bee medications commonly used such as oxalic acid and fumagillin should be more investigated and should be considered by beekeepers and particularly queen breeders.

Mechanisms of deleterious effects of some pesticide exposure on pigs

The increase in the size of the global population increases the food and energy demand, making the use of pesticides in agricultural and livestock industries unavoidable. Exposure to pesticides can be toxic to the non-target species, such as humans, wildlife, and livestock, in addition to the target organisms. Various chemicals are used in the livestock industry to control harmful organisms, such as insects, weeds, and parasites. Pigs are one of the most important food sources for humans. In addition, pigs can be used as promising models for assessing the risk of absorption of environmental pollutants through the skin and oral exposure since they are physiologically similar to humans. Exposure to numerous environmental pollutants, such as mycotoxins, persistent organic pollutants, and heavy metals, has been reported to adversely affect growth, fertility, and endocrine homeostasis in pigs. Various pesticides have been observed in porcine tissues, blood, urine, and processed foods; however, there is a lack of comprehensive understanding of their effects on porcine health. This review provides a comprehensive description of the characteristics of pesticides that pigs can be exposed to and how their exposure affects porcine reproductive function, intestinal health, and endocrine homeostasis in vivo and in vitro.

The palliative effect of camel milk on hepatic CYP1A1 gene expression and DNA damage induced by fenpropathrin oral intoxication in male rats

The present study investigated the alleviating role of camel milk (CM) in the mitigation of fenpropathrin (FNP) type II pyrethroid induced oxidative stress, alterations of hepatic (CYP1A1) mRNA expression pattern, and DNA damage using the alkaline comet assay (SCGE) in male rats. Sixty male Sprague-Dawley rats were separated into six groups (n = 10): 1st control (C), 2nd corn oil (CO), 3rd (CM): gavaged CM 2ml/rat, 4th (FNP): gavaged FNP 7.09 mg/kg body weight (BW), 5th (FNP pro/co-treated): gavaged CM firstly for 15 days, then CM + FNP by the same mentioned doses and route, 6th (FNP + CM co-treated): gavaged FNP firstly followed by CM by the same mentioned doses and route. Rats were orally gavaged three times per week, day after day for 60 days. FNP exposure significantly reduced serum glutathione (GSH) levels, but significantly increased serum levels of superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA), protein carbonyl (PCO), and 8hydroxy2deoxyguanosine (8OH2dG). Additionally, FNP exposure significantly up-regulated the mRNA expression levels of hepatic CYP1A1 and increased the SCGE indices in whole blood, liver, and spleen tissues of exposed male rats. Administration of CM significantly regulated the FNP induced oxidative stress, reduced hepatic CYP1A1 mRNA expression levels and values of comet assay indices particularly in the (CM + FNP pro/co-treated) group compared to the (FNP + CM co-treated) group. In conclusion, our results indicate, for the first time, that FNP retains an in vivo genotoxic potential at a dose of (1/10 LD₅₀) and up-regulated hepatic CYP1A1 mRNA expression in male rats. Additionally, CM supplements may improve the genotoxic outcomes, oxidative stress, and altered CYP1A1 mRNA expression induced by FNP particularly in the pro/concurrent-treatment compared to the concurrent treatment alone.

Biochemical and molecular changes mediated by plasticizer diethyl phthalate in Chironomus circumdatus (bloodworms)

Plasticizers are used as additives in making plastics. Diethyl phthalate (DEP) is one of the majorly used plasticizers in various products. When plastic materials are dumped in an aquatic system, there is an increase in chances of DEP leaching out and getting deposited in water. Thus the current work focuses on studying the effect of DEP on the larval stages of Chironomus circumdatus. In this study it was found that there was an increase in lipid peroxidation levels indicating imposition of oxidative stress on these larvae due to the exposure of DEP. Changes in the levels of carbohydrates and lipids were also seen. To reduce these effects antioxidant defense system may get activated. Thus investigations showed an increase in enzymatic activity of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and acetylcholinesterases (AchE) and decrease in the activity of glutathione reductase (GR). Nonenzymatic antioxidant glutathione levels were also increased during the post-recovery exposure period. Thus this indicates that both enzymatic, as well as non-enzymatic antioxidants, play a certain role in reducing the stress mediated by DEP. Up-regulation of gene expression of heat shock protein70 (hsp70) was observed, which is one of the conserved protein produced during stress response in many dipterans. Changes in the level of expression of the ecdysone receptor (EcR) gene were also seen in DEP exposed larvae. Thus the insights give us a preliminary indication that physiological and developmental adaptations may take place in these organisms to persist in the DEP contaminated environment. CAPSULE: DEP mediated stress imposes changes in the metabolites and thus activation of antioxidant defense system in aquatic midges of Chironomus circumdatus. Changes in the expression of heat shock protein70 and ecdysone receptor was also seen indicating that DEP mediated stress affects at the molecular level also of the organism. These changes may help them to tolerate and live in DEP polluted water.

Redox imbalance caused by pesticides: a review of OPENTOX-related research

Pesticides are a highly diverse group of compounds and the most important chemical stressors in the environment. Mechanisms that could explain pesticide toxicity are constantly being studied and their interactions at the cellular level are often observed in well-controlled in vitro studies. Several pesticide groups have been found to impair the redox balance in the cell, but the mechanisms leading to oxidative stress for certain pesticides are only partly understood. As our scientific project "Organic pollutants in environment - markers and biomarkers of toxicity (OPENTOX)" is dedicated to studying toxic effects of selected insecticides and herbicides, this review is focused on reporting the knowledge regarding oxidative stress-related phenomena at the cellular level. We wanted to single out the most important facts relevant to the evaluation of our own findings from studies conducted on in vitro cell models.

Assessment of neurohepatic DNA damage in male Sprague-Dawley rats exposed to organophosphates and pyrethroid insecticides

The current work was undertaken to test the genotoxic potential of chlorpyrifos (CPF), dimethoate, and lambda cyhalothrin (LCT) insecticides in rat brain and liver using the single cell gel electrophoresis (comet assay). Three groups of adult male Sprague-Dawley rats were exposed orally to one third LD₅₀of CPF, dimethoate, or LCT for 24 and 48 h while the control group received corn oil. Serum samples were collected for estimation of malondialdehyde (MDA) and glutathione peroxidase (GPx); the brain and liver samples were used for comet assay and for histopathological examination. Results showed that signs of neurotoxicity appeared clinically as backward stretching of hind limb and splayed gait in dimethoate and LCT groups, respectively. CPF, LCT, and dimethoate induced oxidative stress indicated by increased MDA and decreased GPx levels. CPF and LCT caused severe DNA damage in the brain and liver at 24 and 48 h indicated by increased percentage of DNA in tail, tail length, tail moment, and olive tail moment. Dimethoate induced mild DNA damage in the brain and liver at 48 h. Histopathological changes were observed in the cerebrum, cerebellum, and liver of exposed rats. The results concluded that CPF, LCT, and dimethoate insecticides induced oxidative stress and DNA damage associated with histological changes in the brain and liver of exposed rats.

Erythrocytes as a biological model for screening of xenobiotics toxicity

Erythrocytes are the main cells in circulation. They are devoid of internal membrane structures and easy to be isolated and handled providing a good model for different assays. Red blood cells (RBCs) plasma membrane is a multi-component structure that keeps the cell morphology, elasticity, flexibility and deformability. Alteration of membrane structure upon exposure to xenobiotics could induce various cellular abnormalities and releasing of intracellular components. Therefore the morphological changes and extracellular release of haemoglobin [hemolysis] and increased content of extracellular adenosine triphosphate (ATP) [as signs of membrane stability] could be used to evaluate the cytotoxic effects of various molecules. The nucleated RBCs from birds, fish and amphibians can be used to evaluate genotoxicity of different xenobiotics using comet, DNA fragmentation and micronucleus assays. The RBCs could undergo programmed cell death (eryptosis) in response to injury providing a useful model to analyze some mechanisms of toxicity that could be implicated in apoptosis of nucleated cells. Erythrocytes are vulnerable to peroxidation making it a good biological membrane model for analyzing the oxidative stress and lipid peroxidation of various xenobiotics. The RBCs contain a large number of enzymatic and non-enzymatic antioxidants. The changes of the RBCs antioxidant capacity could reflect the capability of xenobiotics to generate reactive oxygen species (ROS) resulting in oxidative damage of tissue. These criteria make RBCs a valuable in vitro model to evaluate the cytotoxicity of different natural or synthetic and organic or inorganic molecules by cellular damage measures.

Oxidative stress and glutathione S-transferase genetic polymorphisms in medical staff professionally exposed to ionizing radiation

PURPOSE

Ionizing radiation (IR) is considered as a diagnostic and therapeutic tool in medicine. However, chronic occupational exposure of medical staff to IR may affect the antioxidant status and, as a result, DNA damage and cancers as well. The objective of our study was to evaluate the oxidative stress profile caused by IR in 29 Tunisian medical staff from radiology and radiotherapy departments, and to find an association between the GSTM1 null, GSTT1 null, and GSTP1 Ile105Val polymorphisms and oxidative stress biomarkers.

MATERIALS AND METHODS

The oxidant biomarkers malondialdehyde (MDA) and advanced oxidation protein product (AOPP) and the activities of the antioxidant superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT) enzymes were spectrophotometrically determined in erythrocytes hemolysates. The analysis of GSTT1 null, GSTM1 null, and GSTP1 Ile105Val polymorphisms was determined for each participant using PCR methods.

RESULTS

A significant increase of white blood cell (WBC) numbers (p < .05) and a significant decrease by 11% of hemoglobin (Hb) (p < .01) were noted in the exposed subjects in our study. Moreover, we report a significant increase of MDA level and the activities of SOD and CAT enzymes of the IR-exposed group compared to controls (p < .001). Interestingly, a close association was noted between the genotypes GSTP1 low active, GSTT1 null, GSTM1 null, and both GSTT1/GSTM1 null and oxidative stress biomarkers, especially with MDA level, SOD, and CAT activities.

CONCLUSIONS

Our findings indicate that the medical staff exposed to low IR levels were under risk of significant oxidative stress that was enhanced by their glutathione S-transferase (GST) polymorphisms.

Sublethal effects of pulp and paper mill effluent on two commonly cultured carps: a SEM- and EDS-based hematological biomarker analysis

Blood being a vehicle for the transport of industrial pollutants in living system, fish hematology is considered as potent biomarker. In the present study, we investigated respective sublethal effects of pulp and paper mill effluents on hematology of two commonly cultured carps, Cyprinus carpio and Ctenopharyngodon idella, using optical, scanning electron microscopy and energy-dispersive X-ray spectroscopy. Irrespective of species, results showed significant decrease in erythrocyte, hematocrit and hemoglobin contents while an increase in white blood cell counts (P < 0.05). We observed an increasing trend of MCV (170.0 ± 3.07 to 193.16 ± 2.5) and MCH (34.31 ± 1.89 to 38.71 ± 3.61) up to 28th day in C. carpio (P < 0.05), while, in C. idella, the highest percent increase in MCV (180.8 ± 2.19) and MCH (32.9 ± 0.62) was observed on seventh exposure day, which subsequently declined, respectively, to 173.1 ± 17.1 and 27.9 ± 2.45 on 28th day. Unlike C. carpio, significant and progressive MCHC declining trend (18.23 ± 0.28 to 16.13 ± 0.31) was observed in C. idella. The most commonly observed abnormalities under SEM include echinocytes, cytoplasmic blebbing, cytoplasmic ring, spherocytes, lobopodial projections and acanthocytes in red blood cells of exposed fishes. EDS further revealed the presence of aluminum, antimony, arsenic, cadmium, mercury, tungsten, zinc and titanium; some of these metals were not even detected in the effluent samples, suggesting the probable metal bio-concentration in fish tissue, and subsequent jeopardization is a major concern particularly in the industrial area. Our study further suggested the use of sensitive and specific techniques like SEM and EDS in fish hematological biomarker analysis along with the conventional approach.

Protective effects of pomegranate peel against hematotoxicity, chromosomal aberrations, and genotoxicity induced by barium chloride in adult rats

CONTEXT

Pomegranate peel (PP) has health benefits including antibacterial, antioxidant, anti-inflammatory, and antimutagenic properties.

OBJECTIVE

This study investigated the biochemical composition and protective effects of PP against hematotoxicity and genotoxicity induced by barium chloride (BaCl2) in adult rats.

MATERIALS AND METHODS

Adult Wistar rats were divided into four groups of six each: control, barium (67 ppm via drinking water), PP (5% via diet), and their combination during 21 d. Oxidative stress was determined by MDA, AOPP, and antioxidant status: CAT, GPx, GSH, Vit C. Osmotic fragility (OF), chromosomal aberrations (CAs), and micronucleus (MN) assays were also studied.

RESULTS

PP showed a rich composition of antioxidant compounds. DPPH test found IC50 value= 5.3 μg/mL and a high polysaccharides content (315 ± 5 mg/g of extract). In vivo study showed a decrease in red blood cells (70%) and platelet counts (46%), hemoglobin content (8%), hematocrit percent (7%), and an 80% increase of white blood cells in Ba-treated rats. A reduction in antioxidant status: catalase, glutathione peroxidase activities, glutathione, and vitamin C levels by 31, 21, 28, and 29%, respectively, and an increase in MDA (46%) and AOPP levels (72%) were also observed compared with controls. BaCl2-treatment showed a significant increase in the frequencies of total chromosomal aberrations with abnormal metaphases and micronucleus in bone-marrow cells. Oxidative stress induced by BaCl2 might be the major cause for chromosomal abnormalities leading to DNA damage.

DISCUSSION AND CONCLUSION

A decrease in hematotoxic and genotoxic effects induced by PP is due to its powerful antioxidant capacity.

Chromium scavenging ability of silver nanoparticles in human erythrocytes, real samples and their effect on the catalase enzyme

The plasmonic sensor (6APA–AgNPs) exhibited good selectivity towards Cr(vi) in real samples. It can be used as preventive xenobiotic for catalase against Cr(vi) induced toxicity.

The ameliorating effects of vitamin E on hepatic antioxidant system and xenobiotic-metabolizing enzymes in fenvalerate-exposed iodine-deficient rats

This study investigated the effects of vitamin E (VE) on hepatic antioxidant system and drug-metabolizing enzymes in fenvalerate (FEN)-exposed iodine-deficient (ID) Wistar rats. ID was produced by perchlorate containing drinking water. VE was introduced by a loading dose of 100 mg/kg/d, i.g. for the first three days in the last week of feeding period; then with a single maintenance dose of 40 mg/kg on the 4th day. During last week, FEN groups (F) received 100 mg/kg/d, i.p. FEN. VE alone did not significantly affect thyroid hormones and antioxidant parameters; however, significantly increased total cytochrome P450 (38%) and cytochrome b5 levels (36%). In all ID groups, plasma thyroid-stimulating hormone (TSH) levels increased markedly, but remained at control level in vitamin E plus FEN receiving iodine-deficient group (IDVF) group. Glutathione peroxidase activity showed marked increases in F (19%) and FEN-exposed iodine-deficient group (IDF, 48%) groups. FEN treatment significantly increased total cytochrome P450 (28%) and thiobarbituric acid reactive substance levels (36%), as well as 7-ethoxyresorufin O-deethylase (120%), 7-penthoxyresorufin O-deethylase (139%) and glutathione S-transferase (15%) activities and decreased total glutathione concentrations (28%) versus control. Overall results suggest that vitamin E has ameliorating effects on the measured parameters in ID and/or FEN exposure.

Selenium modulates β-cyfluthrin-induced liver oxidative toxicity in rats

This study was designed to investigate the possibility of β-cyfluthrin to induce oxidative stress and biochemical perturbations in rat liver and the role of selenium in alleviating its toxic effects. Male Wister rats were randomly divided into four groups of seven each, group I served as control, group II treated with selenium (200 µg/kg BW), group III received β-cyfluthrin (15 mg/kg BW, 1/25 LD50 ), and group IV treated with β-cyfluthrin plus selenium. Rats were orally administered their respective doses daily for 30 days. The administration of β-cyfluthrin caused elevation in lipid peroxidation (LPO) and reduction in the activities of antioxidant enzymes including catalase (CAT), superoxide dismutase (SOD), glutathione S-transferase (GST), glutathione peroxidase (GPx), and glutathione reductase (GR). A decrease in reduced glutathione (GSH) content was also observed. Liver aminotransferases (AST and ALT) and alkaline phosphatase (ALP) were decreased, whereas lactate dehydrogenase (LDH) was increased. Selenium in β-cyfluthrin-induced liver oxidative injury of the rats modulated LPO, CAT, SOD, GSH, GST, GPx, and GR. Also, liver AST, ALT, ALP, and LDH were maintained near normal level due to selenium treatment. It is concluded that selenium scavenges reactive oxygen species and render a protective effect against β-cyfluthrin toxicity.

Erythrocyte osmotic fragility and lipid peroxidation following chronic co-exposure of rats to chlorpyrifos and deltamethrin, and the beneficial effect of alpha-lipoic acid

The present study aimed to evaluate the effect of chronic co-exposure to chlorpyrifos (CPF) and deltamethrin (DLT) on erythrocyte osmotic fragility, lipid peroxidation and the ameliorative effect of alpha-lipoic acid (ALA) on erythrocyte fragility. Thirty-six male Wistar rats divided into six groups of six rats each were used for the study. Groups I (S/oil) and II (ALA) were given soya oil (2 ml/kg) and ALA (60 mg/kg), respectively. Rats in group III (DLT) and IV (CPF) were exposed to DLT (6.25 mg/kg) and CPF (4.75 mg/kg) (1/20th of the previously determined LD₅₀ of 125 mg/kg and 95 mg/kg, respectively, over a period of 48 h). Rats in group V (CPF + DLT) were co-exposed to CPF (4.75 mg/kg) and DLT (6.25 mg/kg), while those in group VI (ALA + CPF + DLT) were pretreated with ALA (60 mg/kg) and then co-exposed to CPF and DLT, 45 min later. The treatments were administered by gavage once daily for a period of 16 weeks. Blood collected at the end of the experimental period were analyzed for erythrocyte osmotic fragility and malondialdehyde (MDA) concentration. The study showed that chronic co-exposure to CPF and DLT resulted in an increase in erythrocyte fragility and MDA concentration which were ameliorated by supplementation with alpha-lipoic acid. The study concluded that repeated co-exposure to CPF and DLT elevated erythrocyte fragility probably due to increased lipid peroxidation, and pretreatment with alpha-lipoic acid ameliorated these alterations.

Protective effects of glucosamine hydrochloride against free radical-induced erythrocytes damage

Glucosamine (GlcN) is an important precursor in the biochemical synthesis of glycosylated proteins and lipids in human body. It gains importance because of its contribution to human health and its multiple biological and therapeutic effects. In this study, the in vitro oxidative hemolysis of rat erythrocyte was used as a model to study the potential protective effect of glucosamine hydrochloride against free radical-induced damage of biological membranes. Glucosamine hydrochloride exhibited dose-dependent DPPH antioxidant activity. Oxidative hemolysis and lipid/protein peroxidation of erythrocytes induced by a water-soluble free radical initiator 2,2'-azobis (2-amidinopropane) dihydrochloride (AAPH) were significantly suppressed by GlcN in a time and dose dependent manner. GlcN also prevented the depletion of cytosolic antioxidant glutathione (GSH) in erythrocytes. These results indicated that glucosamine hydrochloride efficiently protected erythrocytes against free radicals and it could be recommended as a pharmaceutical supplement to alleviate oxidative stress.

Surface structures of gill, scale and erythrocyte of Anabas testudineus exposed to sublethal concentration of cypermethrin

The present study was undertaken to assess the toxicity of sublethal concentrations (0.015, 0.030 and 0.045 ppm) of cypermethrin on the gills, scales and erythrocytes of Anabas testudineus for 21 days. The morphological changes on the gills, scales and erythrocytes of the A. testudineus were observed using scanning electron microscope (SEM). The SEM studies on all the three treated groups revealed several kinds of gills, scales and erythrocytes alterations and modifications with abnormal morphology. Gill alterations included highly active mucous cells, epithelial hyperplasia, fusion of secondary lamellae and epithelial lifting. The scales showed damaged lepidonts. Abnormal erythrocytes (shrunken cells), oozed out cytoplasmic content and lobopodial projections were observed in the erythrocytes of fish after exposure to cypermethrin.

DNA damage and repair following In vitro exposure to two different forms of titanium dioxide nanoparticles on trout erythrocyte

TiO2 has been widely used to promote organic compounds degradation on waste aqueous solution, however, data on TiO2 nanotoxicity to aquatic life are still limited. In this in vitro study, we compare the toxicity of two different families of TiO2 nanoparticles on erythrocytes from Oncorhynchus mykiss trout. The crystal structure of the two TiO2 nanoparticles was analyzed by XRD and the results indicated that one sample is composed of TiO2 in the anatase crystal phase, while the other sample contains a mixture of both the anatase and the rutile forms of TiO2 in a 2:8 ratio. Further characterization of the two families of TiO2 nanoparticles was determined by SEM high resolution images and BET technique. The toxicity results indicate that both TiO2 nanoparticles increase the hemolysis rate in a dose dependent way (1.6, 3.2, 4.8 μg mL(-1) ) but they do not influence superoxide anion production due to NADH addition measured by chemiluminescence. Moreover, TiO2 nanoparticles (4.8 μg mL(-1) ) induce DNA damage and the entity of the damage is independent from the type of TiO2 nanoparticles used. Modified comet assay (Endo III and Fpg) shows that TiO2 oxidizes not only purine but also pyrimidine bases. In our experimental conditions, the exposure to TiO2 nanoparticles does not affect the DNA repair system functionality. The data obtained contribute to better characterize the aqueous environmental risks linked to TiO2 nanoparticles exposure.

Comparative toxicity of CuO nanoparticles and CuSO4 in rainbow trout

This study compared the toxicity and accumulation of two different Cu compounds, CuO nanoparticles (NPs) and soluble CuSO4, in erythrocytes and different tissues in rainbow trout (Oncorhynchus mykiss). The crystal structure of CuO NP analysed by XRD indicates that the NP are Tenorite, a monoclinic CuO. The in vitro toxicity results indicate that both Cu compounds increase the haemolysis rate in a dose-dependent way, but the effect was reduced treating cells with CuO NP. Moreover, both Cu compounds induce DNA damage and the entity of the damage, similarly to haemolysis, was more marked in cells treated with CuSO4. In vivo results, obtained after intraperitoneal injection, showed that Cu concentrations were significantly higher in gills (p<0.0001), kidney (p=0.007) and liver (p<0.05) of exposed fish with a significant increase in plasma Cu concentration 15h after CuSO4 treatment. Cu concentrations were significantly higher in fish exposed to CuSO4 than CuO in kidney (p<0.05) and gills (p<0.0001). Significant DNA damage with respect to controls was detected only when Cu was injected as CuSO4. The present data could serve to evaluate environmental Cu toxicity in fish depending on Cu speciation.

Oxidative stress and biochemical perturbations induced by insecticides mixture in rat testes

The joint action of pyrethroids, lambda-cyhalothrin (LC) in combination with organophosphates, fenitrothione (FNT) on antioxidant defense system and lipid peroxidation biomarkers in rat testes was studied. The results suggest that incubation of testes homogenate with different concentrations of insecticide mixture for different time intervals significantly decreased the activity of antioxidant enzymes, like glutathione S-transferase (GST), superoxide dismutase (SOD) and catalase (CAT), and the level of reduced glutathione (GSH). In addition, a significant inhibition in transaminases (AST, ALT), phosphatases (AcP, AlP) activity and protein content were observed. On the other hand, FNT plus LC increased the cellular lipid peroxidation (LPO) level and the activity of lactate dehydrogenase (LDH). In conclusion, the use of insecticides mixture might cause marked oxidative damage in a concentration and time-dependent manner.

A study of proteotoxicity and genotoxicity induced by the pesticide and fungicide on marine invertebrate (Donax faba)

Chlorpyrifos (CPF) and carbendazim (CBZ) are widely used pesticide and fungicide in India. The 96 h LC(50) values of chlorpyrifos and carbendazim for the marine invertebrate Donax faba, were 247.72 μg L(-1) and 200.82 μg L(-1) respectively. CBZ was found to accumulate less than CPF. Gill, body and foot tissues were used as target organs in biomarker and genotoxic studies. The results showed that treatment with chlorpyrifos and carbendazim increased the MDA levels, decreased the GSH levels and changed the total protein, SOD, CAT, GPx and AChE activities in all the tissues compared to those of the control (p<0.05). These results suggest that lipid peroxidation can be a possible pathway for the toxicity of chlorpyrifos and carbendazim. The antioxidant enzyme levels decrease as a result of the consumption of enzymes to neutralize free radicals generated by CPF and CBZ. Comet tail was observed in the first three doses, in all the tissues, of which the mean tail length differed significantly (p<0.01) from those of the unexposed ones. D. faba can be used as an indicator organism to assess the genotoxic risks of chemical contamination in the marine environment using comet assay. Theses biomarkers can be used further to know these agrochemicals impact on coastal marine bivalves.

Cytotoxic effect of fenitrothion and lambda-cyhalothrin mixture on lipid peroxidation and antioxidant defense system in rat kidney

A mixture of pyrethroids plus organophosphates was assessed for their potential effects on lipid peroxidation, the antioxidant defense system and lactate dehydrogenase (LDH) in rat kidney in vitro. Various insecticide concentrations were incubated with kidney homogenate at 37°C for different incubation times. Treatment with fenitothion (FNT) plus lambda-cyhalothrin (LC) caused a significant induction (P < 0.05) in thiobarbituric acid reactive substances (TBARS), which might be associated to decreased levels of reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST) activities and protein content in rat kidney. However, a significant induction of lactate dehydrogenase (LDH) activity was observed. The effect was concentration and time dependent. It can be concluded that depletion of GSH might indicate that reactive oxygen species (ROS) could be involved in the toxic effects of FNT plus LC which lead to marked perturbations in antioxidant defense system.

Oxidative stress biomarkers and acetylcholinesterase activity in human erythrocytes exposed to clomazone (in vitro)

The aim of this study was to investigate the effect of clomazone herbicide on oxidative stress biomarkers and acetylcholinesterase activity in human erythrocytes in in vitro conditions. The activity of catalase (CAT), superoxide dismutase (SOD) and acetylcholinesterase (AChE), as well as the levels of thiobarbituric acid reactive substances (TBARS) and reduced glutathione (GSH) were measured in human erythrocytes exposed (in vitro) to clomazone at varying concentrations in the range of 0, 100, 250 and 500 µg/L for 1 h at 37 °C.TBARS levels were significantly higher in erythrocytes incubated with clomazone at 100, 250 and 500 µg/L. However, erythrocyte CAT and AChE activities were decreased at all concentrations tested. SOD activity was increased only at 100 µg/L of clomazone. GSH levels did not change with clomazone exposure. These results clearly showed clomazone to induce oxidative stress and AChE inhibition in human erythrocytes (in vitro). We, thus, suggest a possible role of ROS on toxicity mechanism induced by clomazone in humans.

Caffeic acid and quercetin protect erythrocytes against the oxidative stress and the genotoxic effects of lambda-cyhalothrin in vitro

Lambda-cyhalothrin (LTC) is a synthetic pyrethroid with a broad spectrum of insecticidal and acaricidal activities used to control wide range of insect pests in a variety of applications. The aim of this study was to examine (i) the potency of LTC to induce oxidative stress response in rat erythrocytes in vitro and (ii) the role of caffeic acid (20 μM) and/or quercetin (10 μM) in preventing the cytotoxic effects. Erythrocytes were divided into four portions. The erythrocytes of the first portion were incubated for 4 h at 37°C with different concentrations (0, 50 and 100 μM) of LTC. The others portions were pretreated with caffeic acid and/or quercetin for 30 min prior to LTC incubation. Lipid peroxidation, protein oxidation, antioxidant enzyme activities and DNA damage were examined. LTC at different concentrations causes increased levels of lipid peroxidation, protein oxidation, DNA damage and decreased antioxidant enzyme activities. Combined caffeic acid and quercetin pretreatments significantly reduced the levels of lipid peroxidation markers, that is thiobarbituric acid reactive substance (TBARS), protein carbonyls (PCO) and decreased DNA damage in LTC portion. Further, combined caffeic acid and quercetin pretreatment maintain antioxidant enzyme activities and glutathione content near to normal values. These results suggest that LTC exerts its toxic effect by increasing lipid peroxidation, altering the antioxidant enzyme activities and DNA damage. Caffeic acid and quercetin pretreatments prevent the toxic effects of LTC, suggesting their role as a potential antioxidant.

Oxidative stress and hepatotoxicity induced by synthetic pyrethroids-organophosphate insecticides mixture in rat

The effects of organophosphorus [fenitrothion (FNT)] and pyrethroid (lambda-cyhalothrin (LC)] pesticides mixture on the antioxidant defense system and liver function enzymes in rat liver were assessed. Various concentrations of FNT+LC were incubated with liver homogenate at 37°C for various incubation times. Results showed that FNT plus LC caused a significant concentration-dependent and time-related inhibition of glutathione S-transferase (GST), superoxide dismutase (SOD) and catalase (CAT) activities, and reduction of glutathione (GSH) content. The depletion of GSH might indicate that reactive oxygen species could be involved in the toxic effects of FNT plus LC. In addition, a significant inhibition in transaminases (AST, ALT) and phosphatases (AcP, AlP) activities was observed. On the other hand, FNT+LC increased the activity of lactate dehydrogenase (LDH) and thiobarbituric acid reactive substances (TBARS) levels. It can be concluded that such biomarkers may be used in assessing adverse/toxic effects of pesticides as environmental stressors.

Fenvalerate induced hepatic oxidative stress in selenium- and/or iodine-deficient rats

Considering the potential adverse effects of selenium and iodine deficiencies, and frequency of intensive but improper use of insecticides, this study was designed to evaluate the effects of a pyrethroid insecticide, fenvalerate, on the oxidant/antioxidant status of liver using a rat model of iodine and/or selenium deficiency. The study was conducted on eight groups of 3-week old Wistar rats. Iodine and/or selenium deficiency was introduced by feeding the animals with a diet containing <0.005 mg selenium/kg and/or supplying with 1% sodium perchlorate containing drinking water for a period of 7 weeks. Fenvalerate exposure (100 mg/kg/d, i.p., for the last 7 days) in normal rats increased hepatic glutathione peroxidase activity and lipid peroxidation, decreased glutathione content, but did not change the activities of catalase or any of the superoxide dismutase forms; in iodine-deficient animals caused only the elevation of lipid peroxidation; in selenium-deficient animals and in combined iodine/selenium deficiency decreased glutathione peroxidase, increased catalase activities and lipid peroxidation, and decreased all the forms of superoxide dismutase activity only in combined deficiency. These results suggested that fenvalerate is an oxidant stress inducer in rat liver, and its potential effects on pro-oxidant/antioxidant balance may also be important for human populations, particularly with iodine and/or selenium deficiencies.

Pravastatin provides antioxidant activity and protection of erythrocytes loaded Primaquine

Loading erythrocytes with Primaquine (PQ) is advantageous. However, PQ produces damage to erythrocytes through free radicals production. Statins have antioxidant action and are involved in protective effect against situation of oxidative stress. Thus the protective effect of pravastatin (PS) against PQ induced oxidative damage to human erythrocytes was investigated in the current studies upon loading to erythrocytes.The erythrocytes were classified into; control erythrocytes, erythrocytes incubated with either 2 mM of PS or 2 mM of PQ, and erythrocytes incubated with combination of PS plus PQ. After incubation for 30 min, the effect of the drugs on erythrocytes hemolysis as well as some biomarkers of oxidative stress (none protein thiols, protein carbonyl, thiobarbituric acid reactive substance) were investigated.Our results revealed that PS maintains these biomarkers at values similar to that of control ones. On the other hand, PQ cause significant increases of protein carbonyl by 115% and thiobarbituric acid reactive substance by 225% while non-protein thiols were significantly decreased by 112 % compared with control erythrocytes. PS pre-incubation before PQ exerts marked reduction of these markers in comparison with PQ alone. Moreover, at NaCl concentrations between 0.4% and 0.8%, PQ causes significant increase of Red Blood Cells (RBCs) hemolysis in comparison with the other groups (P<0. 001). Scanning electron micrograph indicates spherocytes formation by PQ incubation, but in the other groups the discocyte shape of erythrocytes was preserved.The reduction of protein oxidation and lipids peroxidation by PS is related to antioxidants effect of this statin. Preservation of erythrocytes fragility and morphology by PS are related to its free radicals scavenging effect. It is concluded that pravastatin has protective effect against erythrocytes dysfunction related any situations associated with increased oxidative stress, especially when loaded with PQ.

Oxidative stress induced by atrazine in rat erythrocytes: mitigating effect of vitamin E

The present study investigates the propensity of atrazine to induce oxidative stress and its possible attenuation by vitamin E in rat erythrocytes, which is a convenient model to understand the oxidative damage induced by various xenobiotics. Experimental animals were administered atrazine (300 mg/kg body weight, daily) and/or vitamin E (100 mg/kg body weight, daily) orally for a period of 7, 14, and 21 days. Results indicated that the reduced glutathione (GSH) content of the erythrocytes of atrazine treated rats was significantly decreased as compared to the control group. Co-administration of vitamin E along with atrazine restored the GSH content of erythrocytes nearly to control levels. The activities of antioxidant enzymes such as superoxide dismutase, catalase, glutathione peroxidase, and glutathione-s-transferase were found to be increased significantly in the erythrocytes accompanied by a decrease in the activity of the glucose-6-phosophate dehydrogenase, following atrazine exposure. On the other hand, when vitamin E was co-administered along with atrazine, activities of these enzymes were found to be restored significantly. In conclusion, results of the study demonstrated that atrazine induced oxidative stress in rat erythrocytes, in terms of increased activities of the various antioxidant enzymes, and decreased content of reduced glutathione. However, vitamin E administration ameliorated the effects of atrazine, suggesting that vitamin E is a potential antioxidant against atrazine-induced oxidative stress.

Effect of selected antioxidants in beta-cyfluthrin-induced oxidative stress in human erythrocytes in vitro

beta-Cyfluthrin is one of the most widely used type II pyrethroid in agriculture. The aim of this study was to examine (1) the possibility of beta-cyfluthrin to induce oxidative stress in human erythrocytes in vitro and its effect on catalase (CAT) and superoxide dismutase (SOD) activities as well as (2) the role of melatonin (MEL; 2mM), its precursor--N-acetylserotonin (NAS; 1mM), quercetin (Q; 80 microM) and rutin (R; 80 microM) in alleviating the cytotoxic effects of beta-cyfluthrin. Erythrocytes were divided into portions. The first portion was incubated for 4h at 37 degrees C with different concentrations (0, 43, 215, 1075 ppm) of beta-cyfluthrin. The other portions were preincubated with selected antioxidant, respectively for 30 min and followed by beta-cyfluthrin incubation for 4h. Malondialdehyde (MDA) concentrations, CAT and SOD activities, as well as haemolysis percentage (H) were measured in all treatment portions of erythrocytes. It could be concluded that the in vitro toxicity of beta-cyfluthrin may be associated with oxidative stress. Significant reduction in the activities of CAT was observed at all beta-cyfluthrin concentrations, while SOD activities were significantly decreased only in erythrocytes incubated with the highest beta-cyfluthrin concentration. SOD activity of the non-pretreated erythrocytes exposed to the lowest dose of beta-cyfluthrin was significantly greater when compared to comparably beta-cyfluthrin-exposed antioxidant pretreated cells. The highest concentration of beta-cyfluthrin has caused over 35% haemolysis, and the lowest concentration about 15%. MEL pretreatment had no effect on H and MDA induction by beta-cyfluthrin. NAS, Q and R reduced H and MDA level, but could not prevent induction of these parameters. Compared to other antioxidants NAS appeared to maintain better the CAT activity at control levels for all doses of beta-cyfluthrin. Pretreatment with Q was found to protect against the decrease in SOD activity induced by beta-cyfluthrin.

Stimulatory effect of components of rose flowers on catalytic activity and mRNA expression of superoxide dismutase and catalase in erythrocytes

In the present study, two antioxidant components (polysaccharopeptide complex P(1-a) and condensed tannin P(1-b)) from rose (Rosa rugosa) flowers were each incubated with mouse erythrocytes to investigate their effect on erythrocyte superoxide dismutase (SOD), and catalase (CAT) activities. It was found that the activities of Cu, Zn-SOD and CAT were markedly increased after incubation for 3h with rose flower fractions at the concentration of 500μg/ml. Similar changes were also observed in the erythrocyte gene expression of SOD and CAT. These results show that P(1-a) and P(1-b) are effective antioxidants that increase the activity and the gene expression of SOD and CAT in mouse erythrocytes.

Pyrethroid pesticides and their metabolites in vacuum cleaner dust collected from homes and day-care centers

Urinary metabolites of pyrethroid pesticides have been used as biomarkers to estimate human exposure to the parent insecticide. It is important to establish whether these markers are present in environments or media to which humans are exposed routinely. Failure to account for the contribution of pre-existing markers to urinary concentrations could result in risk assessments that overestimate exposure. The purpose of this study was to quantify the concentrations of 13 selected pyrethroid pesticides and their degradation products in samples of indoor dust that had been collected in vacuum cleaner bags during the children's total exposure to persistent pesticides and other persistent organic pollutants (CTEPP) study of homes and day cares in North Carolina and Ohio. Sieved contents of 85 vacuum cleaner bags were analyzed, and permethrin was found in all samples. Sixty-nine samples contained at least one additional pyrethroid, but none contained more than five pyrethroids in detectable concentrations. Resmethrin, prallethrin, and fenpropathrin were not detected in any samples, while 36 contained phenothrin. The median concentration of permethrin in the samples was 1454ng/g of dust. Excluding permethrin, pyrethroid concentrations were typically less than or equal to 100ng/g of dust. The majority of degradates were present in more than half of the dust samples, usually at concentrations of less than or equal to 100ng/g of dust. For those pyrethroids with a characteristic oxydibenzene group, the cyclopropane degradates were present at higher concentrations than the corresponding benzoic acid moieties. Using urinary concentrations of these metabolites to model human exposure to the parent pyrethroids, may over-estimate risk due to the presence of pre-existing degradates in dust.

Nanotoxicity of TiO(2) nanoparticles to erythrocyte in vitro

Titanium dioxide (TiO(2)) has been considered as non-toxic mineral particles widely used in the fields like cosmetics, food and drug. When the scale come to nanometer, TiO(2) nanoparticles (nano-TiO(2)) exhibits multiple specific characteristics coupled with unknown risks on health. The purpose of this study was to systematically research the influence of nano-TiO(2) on erythrocyte. The results indicated that the erythrocytes treated with nano-TiO(2) underwent abnormal sedimentation, hemagglutination and dose dependent hemolysis, totally differing from those treated with micro-TiO(2). The ghost cells were firstly investigated by using ultra-thin cell section in the case under nano-TiO(2). The mechanism of such adverse effects is (1) the attachment around erythrocyte change the surface native properties and ultimately lead to hemoagglutination; (2) the content leak to the outside of erythrocyte through the breakage induced by both the nano-TiO(2) trans-membrane and the oxidative stress under nano-TiO(2). Our findings imply that nano-TiO(2) may have potential toxicity to human being health.

Fenvalerate, a pyrethroid insecticide, adversely affects sperm production and storage in male rats

The aim of this study was to investigate the potential estrogenic activity of fenvalerate by examining reproductive and fertility capabilities in Wistar rats. Adult male animals were treated for 30 d with 20 or 40 mg/kg/d fenvalerate or corn oil (vehicle) by oral gavage. Further, a possible estrogenic activity of fenvalerate (0.4, 1, 4, 8, or 40 mg/kg) was tested after a 3-d treatment of immature female rats using the uterotrophic assay. Exposure to the higher dose of fenvalerate was toxic to testis and epididymis as shown by a decrease in the absolute weights and sperm counts in both organs. Although the sperm counts were reduced, the fertility and sexual behavior were similar in control rats and rats treated with 40 mg/kg pesticide. Fenvalerate did not exert estrogenic activity in vivo at the tested doses. Data suggest that fenvalerate treatment in this study failed to compromise fertility, possibly due to enhanced reproductive capacity in rodents compared to humans.

Alterations in human red blood cell properties induced by 3-(dimethylamino)phenol (in vitro)

3-(Dimethylamino)phenol (3-DMAP) exists in the environment as a transformation product of ureic herbicides and may also be considered as a derivative of phenoxyherbicides. In this study, the activity of glutathione peroxidase, catalase and superoxide dismutase, as well as the level of free radicals and changes in cell morphology were measured in human erythrocytes exposed (in vitro) to 3-(dimethylamino)phenol. Human erythrocytes were incubated for 1 h in 3-DMAP at concentrations of 10-500 microg per 1 ml erythrocytes of 5% haematocrit. The results show that 3-(dimethylamino)phenol increased the level of free radicals and changed the activity of glutathione peroxidase, catalase, superoxide dismutase and acetylcholinesterase. It also changed cell morphology. All these results corroborated the thesis that 3-DMAP induces oxidative stress in cells. 3-DMAP changed the properties of the cell membrane, caused strong oxidation of haemoglobin, inhibited the levels of enzymatic and non-enzymatic antioxidants, which, in result, lead to generation of free radicals (ROS and semiquinones) that occurred in the exposed cells, predisposing them to oxidative damage.

Lambda-cyhalothrin-induced changes in oxidative stress biomarkers in rabbit erythrocytes and alleviation effect of some antioxidants

Erythrocytes are a convenient model to understand the membrane oxidative damage induced by various xenobiotic-prooxidants. This study was designed to investigate (1) the possibility of lambda-cyhalothrin (LC), a type II pyrethroid, to induce oxidative stress response in rabbit erythrocytes in vitro and its effect on selected antioxidant enzymes and (2) the role of vitamin C (VC; 20mM) and vitamin E (VE; 2mM) in alleviating the cytotoxic effects of LC. Erythrocytes were divided into three groups. The first group, previously prepared erythrocytes was incubated for 4h at 37 degrees C with different concentrations (0, 0.1, 0.5, 1, 2.5, 5mM) of LC. The second and third groups were preincubated with VC or VE, respectively for 20 min and followed by LC incubation for 4h. Following in vitro exposure, LC caused a significant induction of oxidative damage in erythrocytes at different concentrations as evidenced by increased thiobarbituric acid reactive substances (TBARS) levels. However, a significant decrease in the content of sulfhydryl groups (SH-groups), and the activities of acetylcholinesterase (AChE), superoxide dismutase (SOD), catalase (CAT) and glutathione S-transferase (GST) were observed. The response was concentration dependent. VC or VE pretreated erythrocytes showed a significant protection against the cytotoxic effects induced by LC on the studied parameters. In conclusion, antioxidant vitamins especially VE could be able to ameliorate LC-induced oxidative stress by decreasing lipid peroxidation and altering antioxidant defense system in erythrocytes.