The efficacy of anthelmintic therapy of farm animals rapidly decreases due to drug resistance development in helminths. In resistant isolates, the increased expression and activity of drug-metabolizing enzymes (DMEs), e.g. cytochromes P450 (CYPs), UDP-glycosyltransferases (UGTs) and P-glycoprotein transporters (P-gps), in comparison to sensitive isolates have been described. However, the mechanisms and circumstances of DMEs induction are not well known. Therefore, the present study was designed to find the changes in expression of CYPs, UGTs and P-gps in adult parasitic nematodes Haemonchus contortus exposed to sub-lethal doses of the benzimidazole anthelmintic drug albendazole (ABZ) and its active metabolite ABZ-sulfoxide (ABZSO). In addition, the effect of ABZ at sub-lethal doses on the ability to deactivate ABZ during consequent treatment was studied. The results showed that contact of H. contortus adults with sub-lethal doses of ABZ and ABZSO led to a significant induction of several DMEs, particularly cyp-2, cyp-3, cyp-6, cyp-7, cyp-8, UGT10B1, UGT24C1, UGT26A2, UGT365A1, UGT366C1, UGT368B2, UGT367A1, UGT371A1, UGT372A1 and pgp-3, pgp-9.1, pgp-9.2, pgp-10. This induction led to increased formation of ABZ metabolites (especially glycosides) and their increased export from the helminths' body into the medium. The present study demonstrates for the first time that contact of H. contortus with sub-lethal doses of ABZ (e.g. during underdose treatment) improves the ability of H. contortus adults to deactivate ABZ in consequent therapy.
The aim of this study was to characterize biomarker responses, haematological profiles, structural changes and uptake in juvenile rainbow trout exposed to clotrimazole (CLO) at three concentrations (0.01 - [lowest environmentally relevant concentration], 1.0 [highest environmentally relevant concentration] and 10 μg L(-1)) in a semi-static system over a period of 42 days. Antioxidant defence enzymes, which responded to CLO exposure, changed the oxidative stress status of cells, but no differences were observed in lipid peroxidation. Clotrimazole triggered a biphasic response of CYP3A-like activity in liver microsomes, which may indicate a detoxification process in the liver. Histopathological alterations were most pronounced in kidneys and testes in the group exposed to 10 μg L(-1). Structural changes in the kidney included tubulonephrosis and hyaline droplet degeneration in the tubular epithelial cells. The relative proportions of germ cells in testes were changed: The number of spermatozoa was reduced, and the spermatogonia and spermatocytes were increased. The highest CLO concentration was detected in fish liver (3710 ng per gram wet tissue) and kidney (4280 ng per gram wet tissue). Depuration half-life was estimated to be 72, 159, and 682 h in liver, muscle, and kidney, respectively. Taken together, these results provide valuable toxicological data on the effects of CLO on aquatic non-target organisms, which could be useful for further understanding of the potential risks in the real aquatic environment.
- MeSH
- Water Pollutants, Chemical pharmacokinetics toxicity MeSH
- Microsomes, Liver metabolism MeSH
- Liver metabolism MeSH
- Clotrimazole pharmacokinetics toxicity MeSH
- Kidney drug effects metabolism pathology MeSH
- Oncorhynchus mykiss * anatomy & histology metabolism MeSH
- Oxidative Stress drug effects MeSH
- Sperm Count MeSH
- Half-Life MeSH
- Spermatozoa cytology drug effects MeSH
- Muscles metabolism MeSH
- Testis drug effects pathology MeSH
- Animals MeSH
- Check Tag
- Male MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
The fungicide cyproconazole (CPZ) inhibits the biosynthesis of ergosterol, an essential sterol component in fungal cell membrane and can also affect non-target organisms by its inhibitory effects on P450 monooxygenases. The predicted environmental concentration of CPZ is up to 49.05 μg/L and 145.89 μg/kg in surface waters and sediments, respectively, and information about CPZ toxicity towards non-target aquatic organisms is still limited. This study aimed to address the lack of ecotoxicological data for CPZ, and thus, an evaluation of the lethal and sub-lethal effects of CPZ was performed using two freshwater invertebrates (the midge Chironomus riparius and the planarian Dugesia tigrina). The estimated CPZ 48 h LC50 (95% CI) was 17.46 mg/L for C. riparius and 47.38 mg/L for D. tigrina. The emergence time (EmT50) of C. riparius was delayed by CPZ exposure from 0.76 mg/L. On the other hand, planarians showed higher tolerance to CPZ exposure. Sub-lethal effects of CPZ on planarians included reductions in locomotion (1.8 mg/L), delayed photoreceptors regeneration (from 0.45 mg/L), and feeding inhibition (5.6 mg/L). Our results confirm the moderate toxicity of CPZ towards aquatic invertebrates but sub-lethal effects observed also suggest potential chronic effects of CPZ with consequences for population dynamics.
- MeSH
- Water Pollutants, Chemical toxicity MeSH
- Chironomidae drug effects MeSH
- Ecotoxicology MeSH
- Lethal Dose 50 MeSH
- Planarians drug effects MeSH
- Fresh Water chemistry MeSH
- Triazoles toxicity MeSH
- Aquatic Organisms drug effects MeSH
- Dose-Response Relationship, Drug MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
In order to develop an understanding of the role of adjuvants in a popular glyphosate-based herbicide - Roundup® Concentrate Plus (RCP), on non-target organisms, the effects of pure glyphosate [N-(phosphonomethyl)-glycine], RCP and a non-ionic surfactant - polyethoxylated tallowamine (POEA) were studied in the fruit fly Drosophila melanogaster. Acute exposure to sub-lethal concentrations of RCP (15 μg/mL) and POEA (45 μg/mL) reduced (p < 0.001) lifespan of female flies compared to untreated controls or glyphosate (100 μg/mL). Negative geotaxis responses in female flies were reduced (p < 0.05) following acute exposure to sub-lethal concentrations of RCP and POEA whereas glyphosate did not significantly affect this response compared to untreated flies. Acute exposure to sub-lethal concentrations of RCP and POEA elevated (p < 0.05) protein carbonyl levels while markedly (p < 0.01) inhibiting carbonyl reductase activity whereas glyphosate treatment did not significantly affect protein carbonyl levels or carbonyl reductase activity. Fecundity was reduced (p < 0.05) following exposure to sub-lethal concentrations of RCP and POEA whereas glyphosate did not affect fecundity. In vitro treatment of ovarian stem sheath (OSS) cells with sub-lethal concentrations of RCP and POEA revealed decreased cell viability and enhanced caspase activity indicative of pro-apoptotic processes after 48 h compared to untreated controls. Glyphosate however was non-toxic at the concentration used. The results suggest that RCP and the surfactant POEA are more toxic than pure glyphosate and inhibit fecundity in Drosophila by impairing cell viability through enhanced apoptosis.
- MeSH
- Adjuvants, Pharmaceutic toxicity MeSH
- Apoptosis drug effects MeSH
- Cell Line MeSH
- Longevity drug effects MeSH
- Drosophila melanogaster drug effects physiology MeSH
- Fertility drug effects MeSH
- Glycine analogs & derivatives toxicity MeSH
- Herbicides toxicity MeSH
- Polyethylene Glycols toxicity MeSH
- Surface-Active Agents toxicity MeSH
- Animals MeSH
- Check Tag
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
OBJECTIVES: Previous studies using oral administration of environmentally relevant doses of cyanobacterial biomass containing microcystins (MCs) induced only sub-lethal effects in experimental birds. Therefore, the objective of this study was to obtain data on avian high-dose toxicity of MCs and compute LD50, if possible, following the natural oral route of administration. DESIGN: Responses of birds to single high-dose exposure to MCs were evaluated in fourteen-day old Japanese quail males (Coturnix coturnix japonica) with average body weight of 50 g which were randomly divided into five groups. Birds from four experimental groups were administered 7.5 ml of cyanobacterial biomass suspension containing increasing MCs quantities of 2500, 5000, 10000, and 20000 µg/kg using oral gavage. Controls received an equal dose of drinking water instead of the test substance. Birds were observed for clinical signs of acute toxicity. Survivors were killed on day 5 to obtain body and liver weights. A five-grade semi-quantitative system for histopathological liver damage scoring was used to compare cyanobacterial-biomass-exposed birds against controls. RESULTS: No mortality occurred during the period of five days post exposure in both control and MCs-exposed groups and this high-dose experiment failed to provide data to compute the LD50. Nevertheless, marked sub-lethal effects were recognised in the damage of liver that included dose-dependent changes in the body/liver ratios and morphological changes ranging from mild vacuolar dystrophy to focal liver necroses in the highest exposure group. Hepatic lesions were mainly observed in the pericentral area of the liver. CONCLUSIONS: Though maximum cyanobacterial biomass dose rates that could be administered to birds of the size were used in the present experiment and more pronounced hepatic lesions than after exposure to environmentally relevant doses were observed, birds would probably have survived unless killed for histopathology on day 5 of exposure. These results provide support to previously reported data on sub-lethal effects following exposure to cyanobacterial biomass containing MCs in birds and mortality occurring only in birds under combined action with other stressors.
- MeSH
- Bacterial Toxins toxicity MeSH
- Biomass MeSH
- Coturnix * MeSH
- Hepatocytes drug effects pathology MeSH
- Carcinogens toxicity MeSH
- Lethal Dose 50 MeSH
- Chemical and Drug Induced Liver Injury epidemiology pathology MeSH
- Microcystins toxicity MeSH
- Marine Toxins toxicity MeSH
- Random Allocation MeSH
- Risk Factors MeSH
- Cyanobacteria chemistry MeSH
- Body Weight MeSH
- Organ Size MeSH
- Dose-Response Relationship, Drug MeSH
- Animals MeSH
- Check Tag
- Male MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
Cell therapy of myocardial infarction (MI) is under clinical investigation, yet little is known about its underlying mechanism of function. Our aims were to induce a sub-lethal myocardial infarction in a rabbit, to evaluate the abilities of labeled bone marrow mononuclear cells to migrate from the vessel bed into extracellular space of the myocardium, and to evaluate the short-term distribution of cells in the damaged left ventricle. Sub-lethal myocardial infarction was induced in rabbits by ligation of the left coronary vessel branch (in vivo). The Langendorff heart perfusion model (ex vivo) was used in the next phase. The hearts subjected to MI induction were divided into 3 groups (P1-P3), and hearts without MI formed a control group (C). Nanoparticles-labeled bone marrow mononuclear cells were injected into coronary arteries via the aorta. Perfusion after application lasted 2 minutes in the P1 group, 10 minutes in the P2 and C groups, and 25 minutes in the P3 group. The myocardium of the left ventricle was examined histologically, and the numbers of labeled cells in vessels, myocardium, and combined were determined. The numbers of detected cells in the P1 and C groups were significantly lower than in the P2 and P3 groups. In the P2 and P3 groups, the numbers of cells found distally from the ligation were significantly higher than proximally from the ligation site. Bone marrow mononuclear cells labeled with iron oxide nanoparticles proved the ability to migrate in the myocardium interstitium with significantly higher affinity for the tissue damaged by infarction.
- MeSH
- Staining and Labeling MeSH
- Bone Marrow Cells metabolism pathology ultrastructure MeSH
- Time Factors MeSH
- Myocardial Infarction metabolism pathology MeSH
- Kinetics MeSH
- Coronary Vessels metabolism pathology MeSH
- Metal Nanoparticles MeSH
- Rabbits MeSH
- Leukocytes, Mononuclear MeSH
- Disease Models, Animal MeSH
- Myocardium metabolism pathology MeSH
- Nanoparticles MeSH
- Statistics, Nonparametric MeSH
- Perfusion MeSH
- Heart MeSH
- Iron metabolism MeSH
- Animals MeSH
- Check Tag
- Rabbits MeSH
- Male MeSH
- Animals MeSH
Haemonchus contortus, one of the most pathogenic of all small ruminant parasites, have developed resistance to all used anthelmintics. Detoxification enzymes, e.g. cytochromes P450 (CYPs) and efflux transporters P-glycoproteins (P-gps), which represent the main defense system against harmful xenobiotics, have been suggested to contribute to drug resistance development. The present study was designed to compare the constitutive expression of individual CYPs and P-gps in females and males of H. contortus adults and to follow up on the changes in expression of these genes in nematodes exposed to sub-lethal concentrations of ivermectin (IVM), which might occur during inaccurate treatment. The adults of inbred susceptible-Edinburgh strain (ISE, MHco3) of H. contortus were used for this purpose. The nematodes were incubated ex vivo with or without IVM (1, 10 and 100 nM) in culture medium for 4, 12 and 24 h. After incubation, total RNA was isolated and expression levels of individual CYPs and P-gps were analyzed using qPCR. Our results showed a great variability in the constitutive expression of individual CYPs and P-gps in H. contortus adults. The constitutive expression as well as the inducibility of CYPs and P-gps significantly differed in males and females. Contact of adult nematodes with sub-lethal IVM concentrations led to only minor changes in expression of CYPs, while expression of several P-gps, particularly pgp-9.2 in males and pgp-10, pgp-11 in females was increased significantly in IVM-exposed nematodes. In conclusion, inaccurate treatment of sheep with IVM might contribute to drug resistance development via increased expression of efflux transporters in H. contortus adults.
- MeSH
- Haemonchus drug effects genetics MeSH
- Ivermectin pharmacology MeSH
- Drug Resistance genetics MeSH
- ATP Binding Cassette Transporter, Subfamily B genetics MeSH
- Gene Expression Regulation drug effects MeSH
- Cytochrome P-450 Enzyme System genetics MeSH
- Animals MeSH
- Check Tag
- Male MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
Albendazole (ABZ), widely used benzimidazole anthelmintic, administered to animals enters via excrements into environment and may impact non-target organisms. Moreover, exposure of lower development stages of helminths to anthelmintics may also encourage the development of drug-resistant strains of helminths. In present project, the kinetics of ABZ (10 mg kg(-1) p.o.) and its metabolite (ABZ.SO, ABZSO2) elimination in faeces from treated Texel lambs were studied using UHPLC/MS/MS with the aim to find out their concentrations achievable in the environment. Consequently, the effect of these compounds on lower development stages of Barber's pole worm (Haemonchus contortus) and on germination of white mustard (Sinapis alba) seeds was evaluated. The results showed that ABZ concentrations in faeces excreted in 4-60 h after treatment were above the concentrations lethal for H. contortus eggs. Moreover, pre-incubation with sub-lethal doses of ABZ and ABZ.SO did not increase the resistance of H. contortus eggs and larvae to anthelmintics. On the other hand, concentrations of ABZ and ABZ.SO in faeces are so high that might have negative influence on non-target soil invertebrates. As neither ABZ nor its metabolites affect the germination of mustard seeds, phytoremediation could be considered as potential tool for detoxification of ABZ in the environment.
- MeSH
- Albendazole analysis pharmacology MeSH
- Feces chemistry MeSH
- Haemonchus drug effects growth & development MeSH
- Sinapis drug effects growth & development MeSH
- Germination drug effects MeSH
- Sheep MeSH
- Seeds drug effects MeSH
- Tandem Mass Spectrometry MeSH
- Chromatography, High Pressure Liquid MeSH
- Animals MeSH
- Check Tag
- Male MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
OBJECTIVES: The objective of this study was to examine the hypothesis that a combination of cyanobacterial biomass containing microcystins, acetylcholinesterase inhibitor and anticoagulant can enhance avian toxic effects produced by single exposures only. METHODS: A total of 48 two-month-old Japanese quails (Coturnix coturnix japonica) with average body weight of 160 g were randomly divided into 8 experimental groups of six birds and sex ratio of 1:1. Experimental groups of control Japanese quails (C) and birds exposed to single and combined sub-lethal doses of paraoxon (P), bromadiolone (B), and microcystins in cyanobacterial biomass (M) included: C, P, P+B, B, B+M, P+M, M, and P+B+M. During the 10-day exposure birds in the respective groups received biomass containing 61.62 µg microcystins daily (i.e. 26.54 µg MC-RR, 7.62 µg MC-YR and 27.39 µg MC-LR), two 250 μg/kg doses of paraoxon, and two 500 mg/kg doses of bromadiolone. Group responses were compared using standard plasma biochemistry and antioxidant/oxidative stress parameters in tissues. RESULTS: While single and double combinations of toxicants induced responses in individual biochemical parameters measured and evaluated using univariate statistical analysis, those in the triple exposure were most extensive. The principal component analysis of antioxidant/oxidative stress parameters (glutathione reductase, lipid peroxidation, and ferric reducing antioxidant power) in tissues (liver, kidney, heart, brain, lungs, gonads, and pectoralis major muscle) clearly separated the triple group (P+B+M) from all single and double exposure groups and the control and indicated thus marked joint effects in the overall pattern of antioxidant/oxidative stress responses of this group. The separation was driven by the modification of the ferric reducing antioxidant power levels in heart and brain and the cardiac lipid peroxidation level, in particular. CONCLUSIONS: This experiment contributes to the understanding of the pathogenic mechanisms of combined sub-lethal exposure to natural toxins and agrochemicals and may be used for risk assessment of environmental pollution in birds.
- MeSH
- 4-Hydroxycoumarins toxicity MeSH
- Anticoagulants toxicity MeSH
- Biomass MeSH
- Cholinesterase Inhibitors toxicity MeSH
- Coturnix * MeSH
- Liver drug effects MeSH
- Carcinogens toxicity MeSH
- Muscle, Skeletal drug effects MeSH
- Kidney drug effects MeSH
- Microcystins toxicity MeSH
- Brain drug effects MeSH
- Random Allocation MeSH
- Paraoxon toxicity MeSH
- Lung drug effects MeSH
- Risk Factors MeSH
- Cyanobacteria chemistry MeSH
- Heart drug effects MeSH
- Animals MeSH
- Check Tag
- Male MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
