The toxicity potential of pharmaceuticals found in the Douro River estuary (Portugal): assessing impacts on gonadal maturation with a histopathological and stereological study of zebrafish ovary and testis after sub-acute exposures
| Autor: | Catarina Cruzeiro, Maria João Rocha, M. H. Galante, Tânia Vieira Madureira, Eduardo Rocha, R. A. F. Monteiro |
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| Rok vydání: | 2011 |
| Předmět: |
Male
Drug-Related Side Effects and Adverse Reactions Health Toxicology and Mutagenesis Ovary Propranolol Aquatic Science Biology Andrology Toxicology Random Allocation Testis medicine Sexual maturity Animals Sexual Maturation Gametogenesis Zebrafish Dose-Response Relationship Drug Portugal Oocyte Spermatozoa Gonadosomatic Index Dose–response relationship Drug Combinations medicine.anatomical_structure Toxicity Tests Subacute Toxicity Oocytes Female Water Pollutants Chemical medicine.drug |
| Zdroj: | Aquatic toxicology (Amsterdam, Netherlands). 105(3-4) |
| ISSN: | 1879-1514 |
| Popis: | Concerns associated with pharmaceuticals in aquatic systems demand the establishment of links between xenobiotics and their respective concentrations and impacts on aquatic organisms. Herein, effects of non-steroidal pharmaceuticals in the gonadal maturation of zebrafish (Danio rerio) were evaluated by histopathological and stereological analyses after 21 days of exposure. Carbamazepine, fenofibric acid, propranolol, sulfamethoxazole and trimethoprim were selected, considering their detection in the Douro estuary (Portugal). Exposures were performed with single compounds and mixtures, the exposure concentrations including environmental levels. Overall, quantitative analyses showed a decreasing trend for late maturation stages in male and female gametogenesis with parallel increases in immature gametes. In females, and at the highest concentration mixture, a significant switch between the volume densities of late/mature oocytes versus primary oocytes was observed. On the verge of statistical significance, oocyte atresia was higher in both mixtures (5.75 ± 4.02% for MXA and 5.65 ± 5.27% for MXB) versus control (2.21 ± 1.88%), in accordance with the histological identification of large atretic areas in some fish. Unlike females, males showed significant effects with single exposures. Spermatozoa in controls totalled 53.25 ± 7.13% of the testis volume, decreasing with carbamazepine (47.19 ± 5.30%), fenofibric acid (46.36 ± 4.30%), propranolol (37.22 ± 2.38%) and sulfametoxazole (39.37 ± 5.15%). An increase in spermatocyte percentage was noted with propranolol (40.13 ± 7.36%) and sulfametoxazole (40.84 ± 1.66%) versus control (30.93 ± 6.53%). The changes in maturation dynamics did not impact the gonadosomatic index. The results show that pharmaceuticals from various therapeutic classes can disrupt the maturation dynamics of fish ovaries and testes. Further studies are justified to tackle the underlying mechanisms and to gauge the full extent of effects/risks. |
| Databáze: | OpenAIRE |
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