RESUMO
Urban activities pollute aquatic ecosystems, and the integrity of organisms such as fish. The use of cytological techniques, such as the analysis of blood cellular integrity using the Micronucleus test, can help detect mutagenic damage as a result to urban effluents exposure. In this context, this study aimed to evaluate the frequency of micronucleus and other nuclear abnormalities in Oreochromis niloticus fish environmentally exposed to urban effluents in relation to their erythrocyte recovery capacity when exposed to clean water (30 and 45 days). The results indicated high copper, dissolved iron, nickel, and thermotolerant coliform levels in the urban stream. There was no difference in the frequency of micronuclei. In contrast, cells with nuclear nuclei, binucleates, kidney-shaped nuclei, notched nuclei, lobed nuclei, and segmented nuclei decreased according to the time the fish were exposed to clean water. When exposed to clean water, we conclude that urban fish recover from genotoxic and cytotoxic damage.
Assuntos
Ciclídeos , Poluentes Químicos da Água , Animais , Ciclídeos/genética , Ecossistema , Eritrócitos , Testes para Micronúcleos , Água , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise , Dano ao DNARESUMO
Pollution generated by the mining industry can cause harm to wildlife. This study aimed to evaluate the cytotoxicity, genotoxicity and mutagenicity in bats environmentally exposed to open pit mining. Thus, 62 bats of the following species, Carollia perspicillata, Glossophaga soricina, Phyllostomus hastatus, and Desmodus rotundus exposed to mining activities (ferronickel) were used in the analysis. The animals were obtained in samplings in July and November of 2021, totaling 8 days of sampling in the field. The results indicated that species differ in the frequency of genotoxic damage between sampling points within the mining landscape. Cytotoxicity was observed by scoring of karyorrhexis, pyknosis and karyolysis. The most captured species, C. perspicillata, showed differences in DNA damage between exposed and unexposed populations, but no differences were observed between males (n = 14) and females (n = 20). G. soricina was also a sensitive species for indicating a high frequency of DNA damages compared to the omnivore P. hastatus. Elements such as Mn, Cr, Pb, and Zn observed in water samples were at high levels in the mining area. We conclude that bats in mining areas are susceptible to increased DNA damage as already identified for other species.
Assuntos
Antineoplásicos , Quirópteros , Animais , Feminino , Masculino , Mutagênicos/toxicidade , Mutagênese , Animais Selvagens , Dano ao DNARESUMO
We have examined the mutagenic effects of the fungicide Elatus® on tadpoles of Rana catesbeiana and Leptodactylus latrans. Sixty-four tadpoles of each species have been exposed to three concentrations of Elatus® (10, 20, and 50 µg/L-1) during 96 hours. We've carried out the micronucleus test (MN) and erythrocyte nuclear abnormalities (ENAs) in 32 tadpoles of each species, the others 32 tadpoles of each species remained in a solution free of Elatus® during 96 hours, in order to assess the ability to recover from the damage caused by the fungicide. There was significant difference in MNs frequency between the treatment exposed to 50µg/L-1 and the control groups for R. catesbeiana, while for L. latrans, we've found difference between the treatment of 20 µg/L-1, followed by a period without exposure to the contaminant and the control group when all ENAs were analyzed. When we compared the two species, R. catesbeiana presented a higher frequency of MNs than L. latrans in the treatment exposed to 50 µg/L-1of the fungicide. Our findings highlight the need to monitor amphibians in places where this product is widely used.
Assuntos
Fungicidas Industriais , Mutagênicos , Animais , Anuros , Larva , Mutagênicos/farmacologia , Rana catesbeianaRESUMO
Free-living birds play an important role as bioindicators in natural environments. In this study, we used the micronucleus test and nuclear erythrocyte abnormalities to investigate the difference in the genotoxic damage frequency between animals in agricultural areas (soybean planting) in relation to the conserved area. It was also discussed the bird's eating habits, which are important for ecotoxicological analysis. The results point to a difference between the insectivorous, granivorous, and omnivorous guilds. The omnivore Gnorimopsar chopi was the species that most exhibited micronucleus frequency in the protected area. In the agricultural area, the animals did not differ in the genotoxic damage frequency. In the comparison between common species in both environments, G. chopi from the agricultural area showed a micronuclei frequency almost three times higher in relation to specimens collected in the conserved area. Based on these results, this study adds to the efforts of using the micronucleus test as a simple and accessible tool for biomonitoring the wild fauna. It can be concluded that the passerine, G. chopi, due to its higher genotoxic damage frequency may be a strong candidate to indicate environmental health.
Assuntos
Animais Selvagens , Aves/genética , Dano ao DNA , Testes para Micronúcleos , Agricultura , Animais , Animais Selvagens/genética , Brasil , Ecotoxicologia , Monitoramento Ambiental , Passeriformes/genéticaRESUMO
Habitat loss and fragmentation together represent the most significant threat to the world's biodiversity. In order to guarantee the survival of this diversity, the monitoring of bioindicators can provide important insights into the health of a natural environment. In this context, we used the comet assay and micronucleus test to evaluate the genotoxic susceptibility of 126 bats of eight species captured in soybean and sugarcane plantation areas, together with a control area (conservation unit) in the Cerrado savanna of central Brazil. No significant differences were found between the specimens captured in the sugarcane and control areas in the frequency of micronuclei and DNA damage (comet assay). However, the omnivore Phyllostomus hastatus had a higher frequency of nuclear abnormalities than the frugivore Carollia perspicillata in the sugarcane area. Insectivorous and frugivorous bats presented a higher frequency of genotoxic damage than the nectarivores in the soybean area. In general, DNA damage and micronuclei were significantly more frequent in agricultural environments than in the control area. While agricultural development is an economic necessity in developing countries, the impacts on the natural landscape may result in genotoxic damage to the local fauna, such as bats. Over the medium to long term, then DNA damage may have an increasingly negative impact on the wellbeing of the local species.
Assuntos
Quirópteros , Agricultura , Animais , Brasil , Dano ao DNA , PradariaRESUMO
The sensitivity of anuran to the effects of habitat destruction and contamination has led to a preoccupying global decline in their populations. Morphological biomarkers such as micronuclei and other erythrocyte nuclear abnormalities (ENAs), as well as the occurrence of hepatic melanin, can be used to evaluate the effects of habitat impacts. In the present study, these two parameters were combined for the in situ assessment of the effects of soybean cultivation on the grassfrog, Leptodactylus fuscus. Specimens were also collected from a protected area to provide a reference site (non-agricultural environment). The frequency of some of the nuclear abnormalities in the animals from the soybean plantation was much higher than that recorded at the reference site, in particular micronuclei, which were 3.6 times more frequent in the plantation, lobulated nuclei (3.4 times more frequent), and reniform nuclei, which were four times more common than at the reference site. The combined analysis of all the ENAs together also revealed a frequency approximately 1.4 times higher in the animals from the soybean plantation, in comparison with the protected area. Smaller areas of hepatic melanin were observed in the specimens from the soybean plantation. These results provide further evidence of the sensitivity of anurans to habitat impacts and indicate that animals found in soybean plantations are susceptible to systematic alterations of their cells.
Assuntos
Anuros , Melaninas , Animais , Brasil , Ecossistema , Eritrócitos , PradariaRESUMO
The micronucleus test has been applied for more than three decades in tadpoles, generating an early warning of environmental quality. In this study, we reviewed 48 articles on the micronucleus test in tadpoles, published between 1987 and 2018. The findings reveal that pesticides have been the main topic discussed in the induction of micronucleus and other nuclear abnormalities in anuran larvae to the detriment of the widespread use of compounds used in agriculture. In addition to pesticides, a number of other xenobiotic agents have been targeted for genotoxic damage, such as heavy metals, radiation and wastewater. An appeal is reported to environmental contaminants, which when released naturally into the environment or because of human activities may contaminate aquatic habitats, threatening populations of tadpoles that depend on these environments for their survival. Larvae can bioaccumulate these contaminants that cause progressive impacts, ranging from DNA damage to metamorphosis delays, as well as malformations. We found that Argentina is the main driving force for the application of this test in anuran larvae along with Brazil. Different erythrocyte malformations have been reported for the erythrocyte nuclear abnormalities test, binucleated cells, nuclear buds, notched, lobed, reniform, nuclear bebbled, anucleated, picnotic and apoptotic cells are the most cited. In summary, the presence of chemical or physical agents, along with other disturbances of the habitat, can have a significant impact on the life history of the species, contributing to the decline of anuran populations.
Assuntos
Anuros/genética , Ecotoxicologia/tendências , Eritrócitos/efeitos dos fármacos , Larva/efeitos dos fármacos , Larva/genética , Testes para Micronúcleos , Agricultura , Animais , Argentina , Brasil , Dano ao DNA , Ecossistema , Monitoramento Ambiental/métodos , Poluição Ambiental , Eritrócitos/patologia , Eritrócitos/fisiologia , Metais Pesados/toxicidade , Metamorfose Biológica/efeitos dos fármacos , Publicações Seriadas , Poluentes Químicos da Água/toxicidadeRESUMO
Estudamos os lipoperóxidos no plasma (BP) e em hemácias (RBC) como malondialdeído (MDA) de 20 controle (grupo I), 10 pacientes com diabetes dependente de insulina (IDDM) bem controlados (grupo II) e 14 pacientes com IDMM mal controlado (grupo III), pareados por idade, sexo e duraçäo da doença. Em cada grupo medimos frutosamina mensalmente (6 determinaçöes) e HBA1c cada 2 meses (3 determinaçöes) durante 6 meses; na última amostra medíamos de novo MDA no BP e em RBC. Um aumento significante de lipoperóxidos foi observado nos pacientes com IDDM mal controlado, mas näo nos pacientes com IDDM controlado; observou-se, também, que os valores de frutosamina e HbA1c correlacionam-se com os níveis de lipoperóxidos. Em outro grupo de pacientes usamos drogas anti-oxidantes por 1 ano em 95 pacientes com diabetes (25 do tipo I e 10 do tipo II), tendo como controles outros 70 paciente com diabetes (20 do tipo I e 50 do tipo II). Em ambos os grupos medimos HBA1c a cada 3 meses, 3 determinaçöes antes e 4 após o início dos anti-oxidantes. Nos 95 pacientes recebendo anti-oxidantes a HbA1c caiu de 12 ñ 4 por cento para 9 ñ 2.1 após 1 ano (p< 0,001), diferentemente do grupo controle (12,6 ñ 3.8 por cento x 11,8 ñ 2,6.1). Esses dados sugerem que a terapêutica anti-oxidante pode ser de importância no tratamento do diabetes mellitus