Pre- and postnatal evaluation of offspring rats exposed to Origanum vulgare essential oil during mating, gestation and lactation / Avaliação pré e pós-natal da prole de ratos expostos ao óleo essencial de Origanum vulgare durante acasalamento, gestação e lactação

Despite the increasing use of oregano (Origanum vulgare L.) essential oil for therapeutic purposes, pre- and postnatal development of animals offspring exposed to this oil has not yet been evaluated. In line with previous concerns of genotoxicity, in this study adult rats were exposed to different doses of oregano essential oil (3, 9 and 27% vol/vol) during pre-mating, mating, gestation and lactation. Prenatal screening included fetal development and uterine inspection, where the reproductive rate of females such as breeding, pregnancy, delivery, viability and post-implantation loss rate were measured. Postnatal evaluation of rat offspring included motor development, neuroendocrine and behavioral assessment. Body weight of rat dams and signs of dystocia were evaluated daily. Development of physic characteristics and reflex tests of puppies were also assessed. Additionally, these rats, when adults, were submitted to sexual and open field behavioral tests. The main differences among the groups were observed in the indices of mating, pregnancy and post-implantation loss (P < 0.01). Results demonstrated that the treatment of parental generation with oregano essential oil has the potential to affect the developing fetuses at the highest dose used, but without causing maternal toxicity and changes in general behavior and development of the progeny.

Apesar do aumento do uso do óleo essencial de orégano (Origanum vulgare L.) para fins terapêuticos, o desenvolvimento pré e pós-natal da progênie de animais expostos a este óleo ainda não foi avaliado. Partindo das suspeitas prévias de genotoxicidade desse óleo, neste estudo, ratos Wistar adultos foram expostos a diferentes doses do óleo essencial de orégano (3, 9 e 27% vol/vol) durante o acasalamento, a gestação e a lactação. Para a avaliação pré-natal, o desenvolvimento gestacional foi observado e os úteros inspecionados, assim como os índices reprodutivos das fêmeas, como a taxa de acasalamento, de gestação, parto e perdas pós-implantação. Na avaliação pós-natal, observou-se o desenvolvimento motor, neuroendócrino e comportamental da prole. Observou-se, diariamente, o peso das ratas e sinais de distocia. Após o parto, as características de desenvolvimento e testes de reflexos dos filhotes foram avaliadas, enquanto que, na puberdade, foram realizadas análises histopatológicas e dosagem hormonal. Adicionalmente, na idade adulta, esses ratos foram submetidos ao teste de comportamento em campo aberto e ao comportamento sexual. As principais diferenças entre os grupos foram nos índices de acasalamento, de gestação e de perdas pós-implantação (P < 0,01). Os resultados demonstram que o tratamento da geração parental com óleo essencial de orégano tem potencial para afetar os índices reprodutivos das ratas e o desenvolvimento dos fetos na maior dose utilizada, mas sem causar toxicidade materna e alterações no desenvolvimento geral e comportamental da sua progênie.

Pre- and postnatal evaluation of offspring rats exposed to Origanum vulgare essential oil during mating, gestation and lactation / Avaliação pré e pós-natal da prole de ratos expostos ao óleo essencial de Origanum vulgare durante acasalamento, gestação e lactação

Despite the increasing use of oregano (Origanum vulgare L.) essential oil for therapeutic purposes, pre- and postnatal development of animals offspring exposed to this oil has not yet been evaluated. In line with previous concerns of genotoxicity, in this study adult rats were exposed to different doses of oregano essential oil (3, 9 and 27% vol/vol) during pre-mating, mating, gestation and lactation. Prenatal screening included fetal development and uterine inspection, where the reproductive rate of females such as breeding, pregnancy, delivery, viability and post-implantation loss rate were measured. Postnatal evaluation of rat offspring included motor development, neuroendocrine and behavioral assessment. Body weight of rat dams and signs of dystocia were evaluated daily. Development of physic characteristics and reflex tests of puppies were also assessed. Additionally, these rats, when adults, were submitted to sexual and open field behavioral tests. The main differences among the groups were observed in the indices of mating, pregnancy and post-implantation loss (P < 0.01). Results demonstrated that the treatment of parental generation with oregano essential oil has the potential to affect the developing fetuses at the highest dose used, but without causing maternal toxicity and changes in general behavior and development of the progeny.(AU)

Apesar do aumento do uso do óleo essencial de orégano (Origanum vulgare L.) para fins terapêuticos, o desenvolvimento pré e pós-natal da progênie de animais expostos a este óleo ainda não foi avaliado. Partindo das suspeitas prévias de genotoxicidade desse óleo, neste estudo, ratos Wistar adultos foram expostos a diferentes doses do óleo essencial de orégano (3, 9 e 27% vol/vol) durante o acasalamento, a gestação e a lactação. Para a avaliação pré-natal, o desenvolvimento gestacional foi observado e os úteros inspecionados, assim como os índices reprodutivos das fêmeas, como a taxa de acasalamento, de gestação, parto e perdas pós-implantação. Na avaliação pós-natal, observou-se o desenvolvimento motor, neuroendócrino e comportamental da prole. Observou-se, diariamente, o peso das ratas e sinais de distocia. Após o parto, as características de desenvolvimento e testes de reflexos dos filhotes foram avaliadas, enquanto que, na puberdade, foram realizadas análises histopatológicas e dosagem hormonal. Adicionalmente, na idade adulta, esses ratos foram submetidos ao teste de comportamento em campo aberto e ao comportamento sexual. As principais diferenças entre os grupos foram nos índices de acasalamento, de gestação e de perdas pós-implantação (P < 0,01). Os resultados demonstram que o tratamento da geração parental com óleo essencial de orégano tem potencial para afetar os índices reprodutivos das ratas e o desenvolvimento dos fetos na maior dose utilizada, mas sem causar toxicidade materna e alterações no desenvolvimento geral e comportamental da sua progênie.(AU)

Reproductive toxicity assessment of Origanum vulgare essential oil on male Wistar rats

Background: The oregano essential oil (Origanum vulgare L.) is rich in phenolic compounds with therapeutic actionssuch as antimicrobial, antifungal and antioxidant. Based on the therapeutic potential and clinical use of oregano essentialoil, in vivo toxicology studies of oregano essential oil are scarce and the current researches focus on the genotoxicity ofseveral species of oregano; however, toxicological and complementary studies are needed to ensure safety of formulationscontaining this oil. Through values of Minimum Inhibitory Concentration (MIC) of oregano essential oil against Candidaspecies, and increased in an exponential scale, the initial dose was obtained. This study aims to evaluate male fertilitythrough the reproductive aspects of rats chronically treated with oregano essential oil.Materials, Methods & Results: The rats were divided into five groups with 10 males and 30 females each; three groupswere treated with oregano essential oil at a concentration of 3% Vol/Vol (GO3%), of 9% Vol/Vol (GO9%) and of 27% Vol/Vol (GO27%). The negative control group received the vehicle, 0.001% Vol/Vol Tween 80 (GC-) and the positive controlgroup was treated with thymol and terpinen-4-ol, at the same concentration found in the oregano essential oil, detected bygas chromatography (3% + 3% Vol/Vol) (GC+). Animals were allowed to adapt for at least ten days before the beginningof the experiment. They were maintained under...(AU)

Reproductive toxicity assessment of Origanum vulgare essential oil on male Wistar rats

Background: The oregano essential oil (Origanum vulgare L.) is rich in phenolic compounds with therapeutic actionssuch as antimicrobial, antifungal and antioxidant. Based on the therapeutic potential and clinical use of oregano essentialoil, in vivo toxicology studies of oregano essential oil are scarce and the current researches focus on the genotoxicity ofseveral species of oregano; however, toxicological and complementary studies are needed to ensure safety of formulationscontaining this oil. Through values of Minimum Inhibitory Concentration (MIC) of oregano essential oil against Candidaspecies, and increased in an exponential scale, the initial dose was obtained. This study aims to evaluate male fertilitythrough the reproductive aspects of rats chronically treated with oregano essential oil.Materials, Methods & Results: The rats were divided into five groups with 10 males and 30 females each; three groupswere treated with oregano essential oil at a concentration of 3% Vol/Vol (GO3%), of 9% Vol/Vol (GO9%) and of 27% Vol/Vol (GO27%). The negative control group received the vehicle, 0.001% Vol/Vol Tween 80 (GC-) and the positive controlgroup was treated with thymol and terpinen-4-ol, at the same concentration found in the oregano essential oil, detected bygas chromatography (3% + 3% Vol/Vol) (GC+). Animals were allowed to adapt for at least ten days before the beginningof the experiment. They were maintained under...