Avaliação da mutagenicidade do indoxacarbe em ratos e gatos / Mutagenicity assessment of indoxacarb in rats and cats

Background: Pesticides are substances used for pest control. Due to their persistence in the environment, they can induce toxicity in humans and animals. Indoxacarb is an oxadiazine insecticide that acts against insects of the order Lepidoptera. Choice of rats and cats used in this study is based on factors such as these animals have a high count of micronucleated polychromatic erythrocytes and the product is intended for use in cats. Limited data in literature pertaining to the mutagenic effects of this product motivated this study. The aim of this study was to evaluate the effect of the micronucleus test on the mutagenicity of indoxacarb when administered in one and tenfold therapeutic doses in rats and cats.Materials, Methods & Results: Forty male Wistar rats aged 70 days and weighing 280 ± 10 g and 20 mixed breed male and female adult cats weighing 4 ± 0.2 kg were selected. These animals were obtained from the central animal facility and cattery, respectively, of the university of origin. Rats were reared in individual cages with a controlled temperature of 22°C ± 2°C, humidity of 55% ± 5% and 12-h light–dark cycle. Cats were reared in individual stalls with water and food ad libitum. Animals were randomly distributed into four groups comprising 10 rats and 5 cats in respective groups: negative control group, which received 0.9% sodium chloride solution as a single topical administration; positive control group, which received 50 mg/kg cyclophosphamide as a single intra-peritoneal (rats) or intravenous injection (cats); indoxacarb group, which received indoxacarb as a single topical dose according to the manufacturers recommendations; and high dose indoxacarb group, which also received indoxacarb in a single topical dose, but at a tenfold concentration. Rats were evaluated 24 h after indoxacarb administration. After euthanasia, rat femurs were obtained and their medullary canals were washed using fetal bovine serum.[...](AU)

Avaliação da mutagenicidade do indoxacarbe em ratos e gatos / Mutagenicity assessment of indoxacarb in rats and cats

Background: Pesticides are substances used for pest control. Due to their persistence in the environment, they can induce toxicity in humans and animals. Indoxacarb is an oxadiazine insecticide that acts against insects of the order Lepidoptera. Choice of rats and cats used in this study is based on factors such as these animals have a high count of micronucleated polychromatic erythrocytes and the product is intended for use in cats. Limited data in literature pertaining to the mutagenic effects of this product motivated this study. The aim of this study was to evaluate the effect of the micronucleus test on the mutagenicity of indoxacarb when administered in one and tenfold therapeutic doses in rats and cats.Materials, Methods & Results: Forty male Wistar rats aged 70 days and weighing 280 ± 10 g and 20 mixed breed male and female adult cats weighing 4 ± 0.2 kg were selected. These animals were obtained from the central animal facility and cattery, respectively, of the university of origin. Rats were reared in individual cages with a controlled temperature of 22°C ± 2°C, humidity of 55% ± 5% and 12-h light–dark cycle. Cats were reared in individual stalls with water and food ad libitum. Animals were randomly distributed into four groups comprising 10 rats and 5 cats in respective groups: negative control group, which received 0.9% sodium chloride solution as a single topical administration; positive control group, which received 50 mg/kg cyclophosphamide as a single intra-peritoneal (rats) or intravenous injection (cats); indoxacarb group, which received indoxacarb as a single topical dose according to the manufacturer’s recommendations; and high dose indoxacarb group, which also received indoxacarb in a single topical dose, but at a tenfold concentration. Rats were evaluated 24 h after indoxacarb administration. After euthanasia, rat femurs were obtained and their medullary canals were washed using fetal bovine serum.[...]

Evaluation of genotoxicity and cytotoxicity of water samples from the Sinos River Basin, southern Brazil

p>Some water bodies in the Sinos River Basin (SRB) have been suffering the effects of pollution by residential, industrial and agroindustrial wastewater. The presence of cytotoxic and genotoxic compounds could compromise the water quality and the balance of these ecosystems. In this context, the research aimed to evaluate the genotoxicity and cytotoxicity of the water at four sites along the SRB (in the cities of Santo Antônio da Patrulha, Parobé, Campo Bom and Esteio), using bioassays in fish and cell culture. Samples of surface water were collected and evaluated italic>in vitro /italic> using the italic>Astyanax jacuhiensis /italic> fish species (micronucleus test and comet assay) and the Vero lineage of cells (comet assay and cytotoxicity tests, neutral red - NR and tetrazolium MTT). The micronucleus test in fish showed no significant differences between the sampling sites, and neither did the comet assay and the MTT and NR tests in Vero cells. The comet assay showed an increase in genetic damage in the fish exposed to water samples collected in the middle and lower sections of the basin (Parobé, Campo Bom and Esteio) when compared to the upper section of the basin (Santo Antônio da Patrulha). The results indicate contamination by genotoxic substances starting in the middle section of the SRB. /p>

p>Alguns corpos dágua da Bacia Hidrográfica do Rio dos Sinos (BHRS) vêm sofrendo os efeitos da poluição por efluentes domésticos, industriais e agroindustriais. A presença de compostos citotóxicos e genotóxicos pode comprometer a qualidade da água e o equilíbrio desses ecossistemas. Neste contexto, o objetivo do trabalho foi avaliar a genotoxicidade e a citotoxicidade da água em quatro pontos ao longo da BHRS (Santo Antônio da Patrulha, Parobé, Campo Bom e Esteio), utilizando bioensaios em peixes e em cultura celular. As amostras de água de superfície foram coletadas e avaliadas italic>in vitro /italic> utilizando a espécie de peixe italic>Astyanax jacuhiensis /italic> (teste de micronúcleo e ensaio cometa) e a linhagem celular tipo Vero (ensaio cometa e os testes de citotoxicidade vermelho neutro - VN e tetrazólio MTT). O teste de micronúcleos em peixes não apresentou diferenças significativas entre os pontos de coleta, assim como o ensaio cometa e os testes VN e MTT nas células Vero. O ensaio cometa demonstrou aumento nos danos genéticos em peixes expostos às amostras de água coletadas nos trechos médio e inferior da bacia (Parobé, Campo Bom e Esteio) em relação ao trecho superior da bacia (Santo Antônio da Patrulha). Os resultados indicam contaminação por substâncias genotóxicas a partir do trecho médio da BHRS. /p>

Evaluation of genotoxicity and cytotoxicity of water samples from the Sinos River Basin, southern Brazil / Avaliação da genotoxicidade e da citotoxicidade de amostras de água da Bacia do Rio dos Sinos, sul do Brasil

Some water bodies in the Sinos River Basin (SRB) have been suffering the effects of pollution by residential, industrial and agroindustrial wastewater. The presence of cytotoxic and genotoxic compounds could compromise the water quality and the balance of these ecosystems. In this context, the research aimed to evaluate the genotoxicity and cytotoxicity of the water at four sites along the SRB (in the cities of Santo Antônio da Patrulha, Parobé, Campo Bom and Esteio), using bioassays in fish and cell culture. Samples of surface water were collected and evaluated in vitro using the Astyanax jacuhiensis fish species (micronucleus test and comet assay) and the Vero lineage of cells (comet assay and cytotoxicity tests, neutral red - NR and tetrazolium MTT). The micronucleus test in fish showed no significant differences between the sampling sites, and neither did the comet assay and the MTT and NR tests in Vero cells. The comet assay showed an increase in genetic damage in the fish exposed to water samples collected in the middle and lower sections of the basin (Parobé, Campo Bom and Esteio) when compared to the upper section of the basin (Santo Antônio da Patrulha). The results indicate contamination by genotoxic substances starting in the middle section of the SRB.(AU)

Alguns corpos dágua da Bacia Hidrográfica do Rio dos Sinos (BHRS) vêm sofrendo os efeitos da poluição por efluentes domésticos, industriais e agroindustriais. A presença de compostos citotóxicos e genotóxicos pode comprometer a qualidade da água e o equilíbrio desses ecossistemas. Neste contexto, o objetivo do trabalho foi avaliar a genotoxicidade e a citotoxicidade da água em quatro pontos ao longo da BHRS (Santo Antônio da Patrulha, Parobé, Campo Bom e Esteio), utilizando bioensaios em peixes e em cultura celular. As amostras de água de superfície foram coletadas e avaliadas in vitro utilizando a espécie de peixe Astyanax jacuhiensis (teste de micronúcleo e ensaio cometa) e a linhagem celular tipo Vero (ensaio cometa e os testes de citotoxicidade vermelho neutro - VN e tetrazólio MTT). O teste de micronúcleos em peixes não apresentou diferenças significativas entre os pontos de coleta, assim como o ensaio cometa e os testes VN e MTT nas células Vero. O ensaio cometa demonstrou aumento nos danos genéticos em peixes expostos às amostras de água coletadas nos trechos médio e inferior da bacia (Parobé, Campo Bom e Esteio) em relação ao trecho superior da bacia (Santo Antônio da Patrulha). Os resultados indicam contaminação por substâncias genotóxicas a partir do trecho médio da BHRS.(AU)

Mutagenic effects of the organophosphate insecticide temephos on mice bone marrow cells / Ação mutagênica do inseticida organofosforado temefós em células de medula óssea de camundongos

The mutagenic effects of organophosphorate temephos on mice bone marrow cells was investigated through the micronucleus formation test. Doses of temephos (27.75; 55.5 e 111.0 mg/kg) were orally administered to males and females Swiss Webster mice. Cyclophosphamide (CPA, 25 mg/kg) per via i.p. and water (10 mL/kg) were administered in mice as positive and negative control groups, respectively. Mutagenic effects were evaluated from 24h to 72h after giving a single dose, and after nine doses of 111.0 mg/kg weekly administered. Ten thousand bone marrow cells per experimental group were analyzed. In the positive controls, the percentages of polychromatic erythrocytes micronucleus (PCEMN) at 24h after a single dose were 1.63% in male and 2.77% in female mice. No PCEMN was observed in the negative controls group. Gradually increasing temephos doses induced PCEMN in 2.61, 3.50, and 3.69% males and 1.02, 1.37, and 1.33% females, respectively. After 72h, CPA caused 0.05% of PCEMN in both males and females; and the temephos caused 0.92% in males and 0.18% in females. In mice administered with nine doses of CPA, PCEMN was detected in 0.15% males and 0.8% females, although PCEMN values were significantly higher in temephos receiving mice group. The mutagenic effects of temephos on both male and female mice were evidenced by chromosome alterations inducing micronucleus formation.

Foram investigados os efeitos mutagênicos do organofosforado temefós através da observação da formação de micronúcleos em eritrócitos policromáticos (PCEMN) da medula óssea de camundongos. Em camundongos Swiss Webster de ambos os sexos, foram administradas diferentes doses de temefós (27,75; 55,5 e 111,0 mg/kg) por via bucal-gástrica e água destilada (10 mL/kg) no grupo controle negativo; e ciclofosfamida (CPA) (25 mg/kg) foi administrada pela via i.p. no grupo controle positivo. Foram analisadas dez mil células da medula óssea por grupo experimental. Os efeitos mutagênicos foram avaliados nos períodos de 24, 48 e 72h após ministrar a dose única e após nove doses de 111,0 mg/kg (1/semana). Em 24h após a dose única de CPA, a formação de PCEMN foi observada em 1,63% dos camundongos machos e 2,77% em fêmeas. Não houve formação de PCEMN no grupo controle negativo. O temefós induziu PCEMN em 2,61%, 3,50% e 3,69% de animais machos e 1,02%, 1,37% e 1,33% em fêmeas. Após 72h, CPA induziu PCEMN em 0,05% de camundongos de ambos sexos e o temefós em 0,92% de machos e 0,18% em fêmeas. Após nove doses de CPA, houve a formação de PCEMN em 0,15% de machos e em 0,8% de fêmeas; para o temefós, os valores observados foram respectivamente de 0,53% e 0,11%. A ação mutagênica de temefós foi demonstrada pela indução de micronúcleos em camundongos de ambos sexos.