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The anti-estrogenic and liver metabolic effects of DHAA in rainbow trout (oncorhynchus mykiss)Pandelides, Zacharias 01 August 2011 (has links)
Recent studies have shown that dehydroabietic acid (DHAA), a resin acid
present in pulp and paper mills, may have anti-estrogenic effects in fish. A
chronic-exposure toxicity experiment using immature rainbow trout
(Oncorhynchus mykiss) was conducted in order to assess the endocrine
disrupting and liver metabolic effects of the wood extractives DHAA and β-
sitosterol (BS) regularly present in pulp and paper mills and the model estrogen
17β-estradiol (E2). It was found that exposure to 5 ppm of E2 significantly
increased hepatosomatic index (HSI), vitellogenin (VTG) and plasma sorbitol
dehydrogenase (SDH). This effect was reduced by mixing E2 with DHAA,
indicating that DHAA does not cause its anti-estrogenic effects indirectly due to
liver damage. Exposure to 5 ppm of DHAA caused a significant increase in liver
citrate synthase (CS), and liver ethoxyresorufin-O-deethylase (EROD) activity
after 7 days, however, the fish recovered by 28 days. This study also determined
the effect of 14 different pulp and paper mill effluent extracts on liver enzyme
metabolism through alterations in the activity of liver lactate dehydrogenase
activity (LDH) and CS. This activity varied greatly between mills but most
showed an induction of CS after 28 days exposure through i.p. injection. The
results of the study indicate that DHAA may alter energy metabolism as well as
cause anti-estrogenic effects in female juvenile rainbow trout. / UOIT
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Uso de bioindicador de efeito endócrino e validação do método para determinação de hormônios na água da Represa Municipal de São José do Rio Preto, SP / Use of the endocrine bioindicator efect and method validation for determination homones in water at reservoir São José do Rio Preto city, SPCordeiro, Daniela 10 December 2009 (has links)
Dentre os vários xenobióticos que as atividades humanas têm produzido nas últimas décadas, os desreguladores endócrinos (EDs), incluindo os hormônios, vêm chamando a atenção de pesquisadores devido aos efeitos que eles causam em animais. Esses efeitos podem resultar em características hermafroditas nos peixes e em anfíbios, inibição do crescimento testicular, inibição da espermatogênese, decrescimento da capacidade de fertilização dos ovos e alteração no comportamento reprodutivo dos seres vivos. Concentrações de apenas 10 ng L-1 de hormônio no meio aquático já são capazes de causar efeito endócrino nos organismos. Neste estudo determinou-se o hormônio natural 17β-estradiol e os hormônios sintéticos levonorgestrel e 17α-etinilestradiol na água da Represa Municipal de São José do Rio Preto (SP). A primeira etapa deste estudo foi a validação dos métodos segundo a Resolução-RE 899 da ANVISA. Os limites de detecção, de quantificação e inferior de quantificação do método para a determinação do 17α-etinilestradiol foram, respectivamente, 25, 100 e 100 ng L-1. A linearidade, desvio-padrão relativo, exatidão e recuperação média para o 17α-etinilestradiol foram, respectivamente, R de 0,98, 3,23%, 100,53% e 89,95%. Os limites de detecção, de quantificação e inferior de quantificação do método para a determinação do 17β-estradiol foram, respectivamente, de 100, 150 e 150 ng L-1. A linearidade, desvio-padrão relativo, exatidão e recuperação média do 17β-estradiol foram, respectivamente, R de 0,99, 3,43%, 106,16% e 89,05%. Para o levonorgestrel, os limites de detecção, de quantificação e inferior de quantificação foram, respectivamente, 50, 150 e 150 ng L-1. A linearidade, desvio-padrão relativo, exatidão e recuperação média do método para a determinação do levonorgestrel foi respectivamente, R de 0,98, 3,48%, 105,15% e 86,45%. Na segunda etapa desta pesquisa analisaram-se amostras de água coletadas na Represa Municipal de São José do Rio Preto (SP) quanto à presença de hormônios. Como método de extração dos hormônios, usou-se a SPE e, como técnica analítica HPLC/FLU/DAD. Os resultados não indicaram a presença dos hormônios estudados até o limite de detecção do método empregado. Foi feita também a análise de vitelogenina (VTG) em plasma sanguíneo de peixes das espécies Geophagus brasiliensis (cará), Satanoperca pappaterra (zoiúdo) e Tilapia rendalli (tilápia rendali) capturados na referida represa. Observou-se que os peixes machos continham concentração de VTG na faixa de 152,4 a 2.841,8 ng mL-1. Isto indica que há substâncias de efeito endócrino na água da represa, mas não se pode afirmar que sejam os hormônios estudados. / Among the several xenobiotics that human activities have produced in the last decades, endocrine disruptors (EDs), including hormones, have been drawing the attention of researches due to the effects they can cause in animals. Those effects may result in hermaphrodite characteristics in fishes and amphibians, testicular growth inhibition, spermatogenesis inhibition, eggs fertilization capacity decrease, and changes in the reproductive behavior of living beings. Concentrations of only 10 ng L-1 of hormones in the aquatic medium are capable of causing endocrine effects in organisms. In this study, the natural hormone 17β-estradiol and the synthetic ones levonorgestrel and 17α-ethinylestradiol were determined in the waters of the São José do Rio Preto (SP) dam. The first step of this study was the validation of the methods according to ANVISA\'s Resolution 899. The detection, quantification, and lower quantification limits of the method for determining 17α-ethinylestradiol were, respectively, 25, 100, and 100 ng L-1. The linearity, relative standard deviation, accuracy, and average recovery of the method for determining 17α-ethinylestradiol were, respectively, R equal to 0.98, 3.23%, 100.53%, and 89.95%. The detection, quantification, and lower quantification limits of the method for determining 17β-estradiol were, respectively, 100, 150, and 150 ng L-1. The linearity, relative standard deviation, accuracy, and average recovery of the method for determining 17β-estradiol were, respectively, R equal to 0.99, 3.43%, 106.16%, and 89.05%. For levonorgestrel, the detection, quantification, and lower quantification limits of the method were, respectively, 50, 150, and 150 ng L-1. The linearity, relative standard deviation, accuracy, and average recovery of the method for determining levonorgestrel were, respectively, R equal to 0.98, 3.48%, 105.15%, and 86.45%. In the second step of this research, samples collected in the São José do Rio Preto (SP) dam were analyzed regarding the presence of hormones. For extracting the hormones, SPE cartridges were used followed by HPLC/FLU/DAD. The results indicated the absence of the studied hormones down to the detection limits of the methods employed. Vitellogenin (VTG) analyses were performed in the blood plasma of fishes captured in the beforementioned dam, of the species Geophagus brasiliensis (pearl cichlid or pearl eartheater), Satanoperca pappaterra (Pantanal eartheater or Paraguay River eartheater), and Tilapia rendalli (redbreast tilapia). It was observed that male fishes had VTG concentrations between 152.4 and 2,841.8 ng mL-1. That indicates that there are substances with endocrine effect in the dam water, although one cannot say the studied hormones are among them.
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Uso de bioindicador de efeito endócrino e validação do método para determinação de hormônios na água da Represa Municipal de São José do Rio Preto, SP / Use of the endocrine bioindicator efect and method validation for determination homones in water at reservoir São José do Rio Preto city, SPDaniela Cordeiro 10 December 2009 (has links)
Dentre os vários xenobióticos que as atividades humanas têm produzido nas últimas décadas, os desreguladores endócrinos (EDs), incluindo os hormônios, vêm chamando a atenção de pesquisadores devido aos efeitos que eles causam em animais. Esses efeitos podem resultar em características hermafroditas nos peixes e em anfíbios, inibição do crescimento testicular, inibição da espermatogênese, decrescimento da capacidade de fertilização dos ovos e alteração no comportamento reprodutivo dos seres vivos. Concentrações de apenas 10 ng L-1 de hormônio no meio aquático já são capazes de causar efeito endócrino nos organismos. Neste estudo determinou-se o hormônio natural 17β-estradiol e os hormônios sintéticos levonorgestrel e 17α-etinilestradiol na água da Represa Municipal de São José do Rio Preto (SP). A primeira etapa deste estudo foi a validação dos métodos segundo a Resolução-RE 899 da ANVISA. Os limites de detecção, de quantificação e inferior de quantificação do método para a determinação do 17α-etinilestradiol foram, respectivamente, 25, 100 e 100 ng L-1. A linearidade, desvio-padrão relativo, exatidão e recuperação média para o 17α-etinilestradiol foram, respectivamente, R de 0,98, 3,23%, 100,53% e 89,95%. Os limites de detecção, de quantificação e inferior de quantificação do método para a determinação do 17β-estradiol foram, respectivamente, de 100, 150 e 150 ng L-1. A linearidade, desvio-padrão relativo, exatidão e recuperação média do 17β-estradiol foram, respectivamente, R de 0,99, 3,43%, 106,16% e 89,05%. Para o levonorgestrel, os limites de detecção, de quantificação e inferior de quantificação foram, respectivamente, 50, 150 e 150 ng L-1. A linearidade, desvio-padrão relativo, exatidão e recuperação média do método para a determinação do levonorgestrel foi respectivamente, R de 0,98, 3,48%, 105,15% e 86,45%. Na segunda etapa desta pesquisa analisaram-se amostras de água coletadas na Represa Municipal de São José do Rio Preto (SP) quanto à presença de hormônios. Como método de extração dos hormônios, usou-se a SPE e, como técnica analítica HPLC/FLU/DAD. Os resultados não indicaram a presença dos hormônios estudados até o limite de detecção do método empregado. Foi feita também a análise de vitelogenina (VTG) em plasma sanguíneo de peixes das espécies Geophagus brasiliensis (cará), Satanoperca pappaterra (zoiúdo) e Tilapia rendalli (tilápia rendali) capturados na referida represa. Observou-se que os peixes machos continham concentração de VTG na faixa de 152,4 a 2.841,8 ng mL-1. Isto indica que há substâncias de efeito endócrino na água da represa, mas não se pode afirmar que sejam os hormônios estudados. / Among the several xenobiotics that human activities have produced in the last decades, endocrine disruptors (EDs), including hormones, have been drawing the attention of researches due to the effects they can cause in animals. Those effects may result in hermaphrodite characteristics in fishes and amphibians, testicular growth inhibition, spermatogenesis inhibition, eggs fertilization capacity decrease, and changes in the reproductive behavior of living beings. Concentrations of only 10 ng L-1 of hormones in the aquatic medium are capable of causing endocrine effects in organisms. In this study, the natural hormone 17β-estradiol and the synthetic ones levonorgestrel and 17α-ethinylestradiol were determined in the waters of the São José do Rio Preto (SP) dam. The first step of this study was the validation of the methods according to ANVISA\'s Resolution 899. The detection, quantification, and lower quantification limits of the method for determining 17α-ethinylestradiol were, respectively, 25, 100, and 100 ng L-1. The linearity, relative standard deviation, accuracy, and average recovery of the method for determining 17α-ethinylestradiol were, respectively, R equal to 0.98, 3.23%, 100.53%, and 89.95%. The detection, quantification, and lower quantification limits of the method for determining 17β-estradiol were, respectively, 100, 150, and 150 ng L-1. The linearity, relative standard deviation, accuracy, and average recovery of the method for determining 17β-estradiol were, respectively, R equal to 0.99, 3.43%, 106.16%, and 89.05%. For levonorgestrel, the detection, quantification, and lower quantification limits of the method were, respectively, 50, 150, and 150 ng L-1. The linearity, relative standard deviation, accuracy, and average recovery of the method for determining levonorgestrel were, respectively, R equal to 0.98, 3.48%, 105.15%, and 86.45%. In the second step of this research, samples collected in the São José do Rio Preto (SP) dam were analyzed regarding the presence of hormones. For extracting the hormones, SPE cartridges were used followed by HPLC/FLU/DAD. The results indicated the absence of the studied hormones down to the detection limits of the methods employed. Vitellogenin (VTG) analyses were performed in the blood plasma of fishes captured in the beforementioned dam, of the species Geophagus brasiliensis (pearl cichlid or pearl eartheater), Satanoperca pappaterra (Pantanal eartheater or Paraguay River eartheater), and Tilapia rendalli (redbreast tilapia). It was observed that male fishes had VTG concentrations between 152.4 and 2,841.8 ng mL-1. That indicates that there are substances with endocrine effect in the dam water, although one cannot say the studied hormones are among them.
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Effects of ibuprofen on Rainbow Trout (Oncorhynchus mykiss) following acute and chronic waterborne exposuresRobichaud, Monique 01 August 2011 (has links)
Pharmaceuticals and personal care products are a growing concern in the aquatic environment. Compounds from the class of non-steroidal anti-inflammatory drugs are commonly detected in surface waters and have the potential to negatively affect aquatic organisms. The purpose of this experiment was to determine the acute and chronic effects of ibuprofen on rainbow trout (Oncorhynchus mykiss). Cyclooxygenase (COX) activity, vitellogenin (VTG) concentration and ethoxyresorufin-O-deethylase (EROD) activity were evaluated following waterborne ibuprofen exposure of trout to 1 and 10 mg/L in the acute exposure and 1, 32 and 1000 μg/L in the chronic exposure, along with an experimental control, E2 control of 1000 μg/L and an E2-ibuprofen mixed treatment. Ibuprofen did not inhibit COX enzyme activity in either gill or kidney tissue. To evaluate the estrogenic effects of ibuprofen, VTG concentrations were measured; by the end of the 56 day chronic exposure VTG concentrations significantly increased in all of the ibuprofen treatments relative to the controls. EROD activity may have been inhibited by ibuprofen but definitive conclusions could not be made. These findings indicate that more research needs to be done studying ibuprofen in aquatic systems. / UOIT
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Effects of Five Substances with Different Modes of Action on Cathepsin H, C and L Activities in Zebrafish EmbryosKüster, Eberhard, Kalkhof, Stefan, Aulhorn, Silke, von Bergen, Martin, Gündel, Ulrike 06 April 2023 (has links)
Cathepsins have been proposed as biomarkers of chemical exposure in the zebrafish embryo
model but it is unclear whether they can also be used to detect sublethal stress. The present study
evaluates three cathepsin types as candidate biomarkers in zebrafish embryos. In addition to other
functions, cathepsins are also involved in yolk lysosomal processes for the internal nutrition of
embryos of oviparous animals until external feeding starts. The baseline enzyme activity of cathepsin
types H, C and L during the embryonic development of zebrafish in the first 96 h post fertilisation
was studied. Secondly, the effect of leupeptin, a known cathepsin inhibitor, and four embryotoxic
xenobiotic compounds with different modes of action (phenanthrene—baseline toxicity; rotenone—an
inhibitor of electron transport chain in mitochondria; DNOC (Dinitro-ortho-cresol)—an inhibitor
of ATP synthesis; and tebuconazole—a sterol biosynthesis inhibitor) on in vivo cathepsin H, C and
L total activities have been tested. The positive control leupeptin showed effects on cathepsin L at
a 20-fold lower concentration compared to the respective LC50 (0.4 mM) of the zebrafish embryo
assay (FET). The observed effects on the enzyme activity of the four other xenobiotics were not or just
slightly more sensitive (factor of 1.5 to 3), but the differences did not reach statistical significance.
Results of this study indicate that the analysed cathepsins are not susceptible to toxins other than the
known peptide-like inhibitors. However, specific cathepsin inhibitors might be identified using the
zebrafish embryo.
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