Thesis (doctoral)--Ludwig-Maximilians-Universität, 1983.

Nonsteroidal anti-inflammatory drugs (NSAIDs), non-selective or selective inhibitors of cyclooxygenase (COX-1 and -2), reduce pain and inflammation associated with arthritic diseases. Celecoxib, a COX-2-selective inhibitor providing decreased gastric injury relative to non-selective NSAIDs, is commonly prescribed. Misoprostol, a prostaglandin analog, supplements NSAID-inhibited prostaglandin levels. As concomitant celecoxib and misoprostol administration has been shown to intensify renal adverse effects, this article examined the influence of concomitant administration on hepatic histopathology, oxidative stress, and celecoxib concentration. On days 1 and 2, rat groups (n = 6) were gavaged twice daily (two groups with vehicle and two groups with 100 μg/kg misoprostol). From day 3 to day 9, one celecoxib dose (40 mg/kg) replaced a vehicle dose of one group and one group received celecoxib in addition to misoprostol. Livers were harvested on day 10. No hepatic abnormalities were observed denoting a lack of influence by either drug. Also no change in mean biomarker levels was detected. The changes in hepatic celecoxib concentration in the misoprostol-receiving group compared to control were not significant. Thus misoprostol does not influence hepatic celecoxib effects in terms of histopathology, oxidative stress, or celecoxib concentration level at the dosage and duration examined.

The World Health Organization has called stress-related illness “the health epidemic of the 21st century.” While the biochemical pathways associated with the acute stress response are well-characterized, many of the pathways behave differently under conditions of chronic stress. The purpose of this project is to apply high-sensitivity mass spectrometry (MS)-based targeted and untargeted metabolomics approaches to generate new insights into the biochemical processes and pathways associated with the chronic stress response, and potential mechanisms by which chronic stress produces adverse health effects. Chapter 1 describes the application of sets of targeted and untargeted metabolomics approaches to analyze serum samples from a human epigenetic model of chronic stress in order to identify potential targets for further analysis. To test the resulting hypothesis that oxidative stress is a key feature of chronic stress, a new targeted multiple reaction monitoring (MRM)-MS assay was developed for the accurate quantitation of aldehyde products of lipid peroxidation, as described in Chapter 2. In Chapter 3, the validated method for quantitation of malondialdehyde (MDA) was t applied to mouse plasma samples from a model of chronic social defeat stress to determine whether animals exposed to psychosocial stress show increases in oxidative stress. Mouse plasma samples from this model were also analyzed by untargeted metabolomics using Fourier-transform (FT)-MS to identify other important metabolite features, particularly those that overlap with metabolites identified in the human epigenetic model. Analysis of metabolomic data from two very different models of chronic stress supports the consistent detection of a metabolomic phenotype for chronic stress that is characterized by the dysregulation of energy metabolism associated with decreased concentrations of diacyl-phospholipids in blood. Increased blood concentrations of fatty acids, carnitines, acylcarnitines, and ether phospholipids were also observed. In addition to metabolites associated with energy metabolism, chronic stress also significantly influenced metabolites associated with amino acid metabolism and cell death. This characteristic pattern of differences in metabolite concentrations was observed in the plasma of mice exposed to chronic social defeat stress, irrespective of whether or not they displayed outward signs of a chronic stress response; In fact, mice that were “resilient” to the behavioural effects of chronic social defeat stress displayed an exaggerated phenotype over mice that showed depressive-like symptoms following chronic stress exposure. This may suggest that the observed changes in fatty acid composition are protective against stress. However, changes in fatty acid composition are also known to be associated with a wide variety of pathologies including heart disease, neurodegenerative diseases, and mood disorders, so the lipidomic changes associated with chronic stress may also contribute to its health impact. Overall, the results provide further evidence that changes in energy metabolism are a central part of allostatic adaptation to chronic stress. / Graduate / 0487 / csobsey@gmail.com

Ácidos graxos polinsaturados Omega-3 (n-3 PUFA) tais como o ácido eicosapentaenóico (C20:5 n-3, EPA) e docosahexaenóico (C22:6 n-3, DHA) reduzem a concentração plasmática de triacilgliceróis em humanos. Entretanto, uma alta proporção desses ácidos graxos na dieta poderia favorecer a susceptibilidade das células à peroxidação, aumentando o risco de desenvolvimento de doenças cardiovasculares. Embora modelos animais não sejam recomendados para avaliar o efeito de n-3 PUFA nas lipoproteínas plasmáticas, estes têm sido amplamente utilizados como modelo para avaliação de dano oxidativo. Diferenças nos procedimentos metodológicos também têm gerado dificuldade na comparação de resultados. Desta forma, o objetivo deste estudo foi aplicar os mesmos procedimentos metodológicos para comparar o efeito da suplementação de n-3 PUFA nos biomarcadores plasmáticos de estresse oxidativo utilizando um modelo humano e um modelo animal. Indivíduos foram aleatoriamente distribuídos em dois grupos num delineamento paralelo duplo cego e receberam uma suplementação de 460,0 mg/dia de n-3 PUFA (OMEGA) contendo 240,0 mg de EPA + 160,0 mg de DHA + 60,0 mg de outros n-3 PUFAs, ou óleo de soja (PLACEBO) durante 6 semanas. Ratos Wistar também foram distribuídos em dois grupos e receberam uma dieta contendo 192,5 mg/dia de n-3 PUFA (FO) sendo 116,3 mg de EPA + 61,5 mg de DHA + 14,7 mg de outros n-3 PUFAs ou óleo de soja (SO) durante 3 semanas. Indivíduos do grupo OMEGA apresentaram maior concentração de malondialdeído (MDA) no plasma medido por TBARS quando comparado aos respectivos valores no baseline. A suplementação com n-3 PUFA não alterou a concentração plasmática de α-tocoferol e a atividade antioxidante determinada pelo método DPPH. Apesar dos animais terem recebido doses 10 vezes maiores de n-3 PUFA (2,9 mg/kcal) quando comparadas aos humanos (0,3 mg/kcal) não foram observadas alterações entre os grupos FO e SO para as concentrações de MDA no plasma e no homogenato de cérebro. Em resumo, pode-se sugerir que o modelo animal usado neste estudo parece não ser o mais adequado para avaliar o estresse oxidativo após intervenções dietéticas com n-3 PUFAs em função de diferenças no metabolismo e nos mecanismos de proteção antioxidante observados entre os dois modelos. / Omega-3 polyunsaturated fatty acids (n-3 PUFA) such as eicosapentaenoic (C20:5 n-3, EPA) and docosahexaenoic (C22:6 n-3, DHA) reduce plasma triacylglycerol concentration in humans. However, higher proportion of these fatty acids in the diet could raise cells lipoperoxidation susceptibility, increasing the cardiovascular disease risk. Although animal models are not recommended to evaluate the effect of n-3 PUFA in plasma lipoproteins, they have been widely used as model for oxidative damage. Difference in methodological proceedings has also caused difficulties to compare data among assays. Thus, the objective of this study was to apply the same methodology to investigate the effect of n-3 PUFA supplementation on oxidative biomarkers in animal and human model. Individuals were randomly assigned in two groups in a parallel double blind design and received a supplement of 460.0 mg/day n-3 PUFA (OMEGA) containing 240.0 mg EPA + 160.0 mg DHA + 60.0 mg other n-3 PUFAs, or soybean oil (PLACEBO) during 6 weeks. Wistar rats were also assigned in two groups and received a diet containing 192.5 mg/day n-3 PUFA (FO) containing 116.3 mg EPA + 61.5 mg DHA + 14.7 mg other n-3 PUFAs or soybean oil (SO) for 3 weeks. Individuals in OMEGA group showed higher malondialdehyde (MDA) concentration in plasma measured by TBARS when compared to their baseline values. N-3 PUFA supplementation did not change plasma α-tocopherol concentration and antioxidant activity determined by DPPH method. Although animals have received a 10-fold higher dose of n-3 PUFA (2.9 mg/ kcal) than humans (0.3 mg/kcal), no alteration was observed between FO and SO groups for plasma and brain homogenate MDA concentration. In summary, it can be suggested that the model used in this study doesn\'t seem appropriate to evaluate oxidative stress after dietetic interventions with n-3 PUFA due to physiological differences involved in lipid metabolism and antioxidant protection observed between both models.

Submitted by LEONEL GONÇALVES PEREIRA NETO null (leonel.neto@embrapa.br) on 2017-02-03T17:52:40Z No. of bitstreams: 1 TESE FINAL LEONEL NETO.pdf: 2494638 bytes, checksum: 43fa52f52edf7397fb036f40e16c379e (MD5) / Approved for entry into archive by LUIZA DE MENEZES ROMANETTO (luizamenezes@reitoria.unesp.br) on 2017-02-07T12:01:15Z (GMT) No. of bitstreams: 1 pereiraneto_lg_dr_bot.pdf: 2494638 bytes, checksum: 43fa52f52edf7397fb036f40e16c379e (MD5) / Made available in DSpace on 2017-02-07T12:01:15Z (GMT). No. of bitstreams: 1 pereiraneto_lg_dr_bot.pdf: 2494638 bytes, checksum: 43fa52f52edf7397fb036f40e16c379e (MD5) Previous issue date: 2016-12-08 / Sementes de diferentes espécies, armazenadas na mesma condição em bancos de germoplasma, apresentam respostas distintas quanto à perda de sua viabilidade. Atualmente, somente o teste de germinação é usado para avaliar a qualidade fisiológica de sementes em bancos de germoplasma e outros métodos ainda são necessários para prever a longevidade de sementes. A espécie Astronium fraxinifolium Schott é uma árvore das regiões da Amazônia, Cerrado e Caatinga, ameaçada de extinção, que apresenta sementes não dormentes e que germinam rapidamente. O objetivo do presente trabalho foi estudar a longevidade de sementes de A. fraxinifolium, coletadas em diversos locais de duas regiões geográficas distintas e avaliar o transcriptoma. Sementes de dez acessos de A. fraxinifolium, sendo seis coletados no estado de Goiás (GO) e quatro em Minas Gerais (MG) foram avaliados. Foram realizados pré-testes para determinar a melhor temperatura para germinação e o tempo para iniciar a protrusão da radícula. Testes de envelhecimento, condutividade elétrica, teor de malonaldeído e análise do transcriptoma foram realizados. A temperatura ótima de germinação foi de 30° C e os primeiros eventos de protrusão radicular ocorreram após 20 horas de embebição. Sementes coletadas em Goiás apresentaram maior viabilidade e longevidade após os testes de envelhecimento para todas as condições testadas e os acessos GO 6 e MG 2 apresentaram, respectivamente, a maior e menor longevidade após o envelhecimento. O teste de condutividade elétrica não foi adequado para avaliar a longevidade dos acessos e a avaliação do teor de malonaldeído foi considerado um teste promissor para avaliar a longevidade de sementes de A. fraxinifolium. Foi realizada análise de RNASeq para avaliar os transcriptomas de eixos embrionários de sementes dos acessos GO 6 e MG 2, com sementes envelhecidas e não envelhecidas. Os genes expressos diferencialmente foram relacionados aos processos de transcrição de RNA, kinases, ubiquitinas, metabolismo de amido, microtúbulos, componentes de membrana, polimerase e transporte de carboidratos e zinco. / Seeds of different species stored under the same conditions differently lose their viability. Currently, the physiological quality of seeds stored in genebanks is evaluated only by the germination test and other methods are still needed to predict seed viability.The species Astronium fraxinifolium Schott is a tree in the Amazonian regions, Cerrado and Caatinga, which presents seeds that are non-dormant and which germinate rapidly. The goal of this work was to study the longevity of seeds A. fraxinifolium collected at several sites from two different geographic regions, and assess the transcriptome. For that, seeds from ten accessions of A. fraxinifolium were collected (six in the state of Goiás (GO) and four in Minas Gerais (MG) and evaluated. Pre-tests were performed to determine the optimal germination temperature and the onset of the radicle protrusion. Aging tests, electrical conductivity, malonaldehyde content and transcriptome analysis were performed. The optimal germination temperature was 30o C and the first radicle protrusion events occurred after 20 hours of imbibition. Seeds collected in Goiás displayed higher viability and longevity after aging in all tested conditions and seeds from accessions GO 6 and MG 2 showed, respectively, the highest and lowest longevity indexes after aging. The electrical conductivity test was not adequate to evaluate the longevity of the accessions and the assessment of the malonaldehyde content was considered a promising test to assess the longevity of A. fraxinifolium seeds. RNASeq analysis was performed to evaluate the transcripts of embryonic axes of seeds of the GO 6 and MG 2 accessions, with aged and unaged seeds. Differentially expressed genes were related to RNA transcription processes, kinases, ubiquitin, starch metabolism, microtubules, membrane components, polymerase, and transport of carbohydrates and zinc.

Selenium (Se) is an essential mineral with functions for both animals and humans. There are several regions in the world deficient in this mineral and studies have related Se supplemented with reducing cholesterol. Thus, the objective of this study was to evaluate the Se effect in different levels and sources in the diet finishing of Nellore cattle on the performance and meat quality. It was used 63 Nellore cattle (412 kg and ± 24 months of age) in a completely randomized design with two sources (sodium selenite and selenium-enriched yeast) and four supplementation levels (0; 0.3; 0.9 and 2.7 mg Se/kg DM). There were no changes in performance and carcass characteristics. The Se level reduced (P<0.01) lipid and proteins oxidation (TBARS and carbonyl) compared to the control treatment on retail display storage (0, 2, 4 and 6 days). Organic Se, regardless of level, provided Se 138% higher (P<0.0001) in meat and 22.6% higher (P<0.0001) in serum than inorganic Se. The activity of glutathione peroxides (GPx) in muscle was 288% higher for animals supplemented with selenium and consequently, the cholesterol concentration in L. dorsi was 10.2% lower (P<0.001). The serum HMG-CoA reductase concentration was 32.7% lower in animals receiving Se supplementation (organic or inorganic). In conclusion, Se supplementation in beef cattle diet is a way of naturally producing selenium-enriched meat and with better quality for human consumption. / O selênio (Se) é um mineral essencial com funções para animais e humanos. Existem várias regiões do mundo deficientes neste mineral e estudos têm relacionado a suplementação de Se com a redução do colesterol. Assim, o objetivo deste estudo foi avaliar o efeito de diferentes teores e fontes de Se na dieta de terminação de bovinos Nelore sobre o desempenho e a qualidade da carne. Foram utilizados 63 animais da raça Nelore (412 kg e ± 24 meses de idade) em delineamento inteiramente casualizado, com duas fontes (selenito de sódio e selênio levedura) e quatro teores de suplementação (0; 0,3; 0,9 e 2,7 mg Se/kg MS) em confinamento, durante 84 dias. Não houve alterações no desempenho e nas características de carcaça. O teor de Se reduziu (P <0,01) a oxidação lipídica e proteica (TBARS e carbonila) em comparação ao tratamento controle durante o armazenamento em simulação de exposição no varejo (0, 2, 4 e 6 dias). O Se orgânico, independentemente do teor, forneceu valor de Se 138% superior (P <0,0001) na carne e 22,6% superior (P <0,0001) no soro em relação ao Se inorgânico. A atividade glutationa peroxidase (GPx) no músculo foi 288% maior nos animais suplementados com selênio e, consequentemente, a concentração de colesterol na carne foi 10,2% menor (P <0,001). A concentração sérica de HMG-CoA redutase foi 32,7% menor nos animais que receberam suplementação de Se (orgânico ou inorgânico). Foi concluído que a suplementação com Se na dieta de bovinos de corte é uma forma de produzir carnes enriquecidas com selênio naturalmente e com melhor qualidade para consumo humano.

The purpose of this study was to determine the effects of high intensity eccentric muscle damage on plasma creatine kinase and plasma malondialdehyde. Twelve subjects, who served as their own control, performed 10 sets of eccentric knee extensions at a 10 RM intensity with their dominant leg. The subjects lowered the resistance in slow controlled manner to a three count of a metronome set at one beat per second. The resistance was set at an intensity equal to 120% of the subject's concentric 1RM. Creatine kinase and malondialdehyde were measured pre-exercise and at 24, 48, 72, 96 and 120 hours post-exercise. Results (p<_ .05) showed a significant increase in both creatine kinase and malondialdehyde compared to baseline. Creatine kinase showed significant increases through 120 hours post-exercise, and peaked at 96 hours post-exercise. Malondialdehyde showed significant increases through 72 post-exercise and peaked at 24 hours postexercise. It appears that a single bout, of high intensity, eccentric exercise can cause significant increases in creatine kinase and malondialdehyde. / Department of Speech Pathology & Audiology

Atlikto darbo tikslas buvo įvertinti kadmio, nikelio bei cinko jonų poveikį metalotioneinų sintezės intensyvumui ir lipidų peroksidacijai laboratorinių pelių organuose – kepenyse ir smegenyse. Šiam tikslui įgyvendinti buvo iškelti uždaviniai: nustatyti metalotioneinų koncentraciją pelių smegenyse ir kepenyse po vienkartinio (24 val.) ir kartotinio (14 dienų) kadmio ir nikelio jonų poveikio; įvertinti ūmų vienkartinį (24 val.) ir kartotinį (14 dienų) kadmio ir nikelio jonų poveikį lipidų peroksidacijai pelių smegenyse ir kepenyse; įvertinti cinko jonų gebą apsaugoti smegenų ir kepenų antioksidacinę sistemą esant toksiniam kadmio ir nikelio jonų poveikiui. Eksperimentams atlikti naudotos baltosios beveislės laboratorinės pelės. Metalotioneinų koncentracija nustatatyta pagal Peixoto ir bendraautorių, o malondialdehido – pagal Uchiyama ir bendraautorių pasiūlytas metodikas. Tyrimo rezultatai parodė, kad tiek kadmio, tiek ir nikelio jonai pelių kepenyse metalotioneinų koncentracijos padidėjimą sukėlė ir po vienkartinio 24 val., ir po kartotinio 14 dienų šių jonų poveikio, o smegenyse – tik praėjus 24 valandoms po kadmio ar nikelio jonų poveikio. Cinko jonai veikdami kartu su kadmio jonais statistiškai reikšmingą metalotioneinų koncentracijos padidėjimą sukėlė smegenyse po 14 dienų šių jonų kompleksinio poveikio. Cinko jonams veikiant kartu su nikelio jonais, statistiškai reikšmingas metalotioneinų koncentracijos padidėjimas taip pat nustatytas smegenyse po 14 dienų šių jonų... [toliau žr. visą tekstą] / The aim of the work was to evaluate the influance of cadmium, nickel and zinc ions on metallothionein synthesis and lipid peroxidation intensity in mice organs – the liver and brain. The tasks of the work were: to determine the concentration of MT in mice brain and liver after both acute (24 hours) and repeated (14 days) influence of cadmium and nickel ions, to evaluate the acute (24 hours) and repeated (14 days) effects of cadmium and nickel ions on lipid peroxidation in mouse brain and liver and to evaluate the ability of zinc ion to protect the brain and liver antioxidant system from the toxicity of cadmium and nickel ions. We used white laboratory mice in our experiments. MT concentration was established according to Peixot and contributors proposed method and MDA concentration – according to Uchiyama and contributors proposed method. The results have shown that both cadmium and nickel ions increased metallothionein concentration in the liver of mice after a single (24 hours) and after repeated (14 days) exposure of these ions. The increased metallothionein concentration in the brain was established only 24 hours after cadmium or nickel ions exposure. Zinc ions in cooperation with the cadmium ions a statistically significant increase of metallothionein levels caused in the brain 14 days after the complex effects of these ions. Zinc ions, acting with the nickel ions, a statistically significant increase of metallothionein concentration caused as well in the brain after 14... [to full text]

Thesis (Ph. D.)--University of Washington, 2005. / Vita. Includes bibliographical references (leaves 99-120).

Submitted by DANIELLY PEREIRA GARCIA null (daniellypgarcia@gmail.com) on 2016-05-31T13:02:05Z No. of bitstreams: 1 Dissertação de Mestrado Danielly P. Garcia.pdf: 1928934 bytes, checksum: 40dac212e7d7b6c4fb6e39b2972fc94f (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-05-31T19:29:56Z (GMT) No. of bitstreams: 1 garcia_dp_me_sjrp.pdf: 1928934 bytes, checksum: 40dac212e7d7b6c4fb6e39b2972fc94f (MD5) / Made available in DSpace on 2016-05-31T19:29:56Z (GMT). No. of bitstreams: 1 garcia_dp_me_sjrp.pdf: 1928934 bytes, checksum: 40dac212e7d7b6c4fb6e39b2972fc94f (MD5) Previous issue date: 2016-03-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Dentre os efeitos negativos da exposição a poluentes nos animais aquáticos podemos destacar o estresse oxidativo, uma produção exacerbada de espécies reativas de oxigênio, consequentemente, uma cascata de eventos bioquímicos denominados peroxidação lipídica (PL) ocorrem tendo como principal produto o malondialdeído (MDA). Assim, ainda que o aumento dos níveis de MDA esteja relacionado a intoxicação por poluentes, alguns trabalhos têm mostrado uma diminuição do MDA frente a essa exposição, mesmo com alterações em enzimas antioxidantes. Deste modo, este trabalho teve por objetivo avaliar se possíveis decréscimos nos níveis de MDA em peixes Astyanax altiparanae expostos a contaminantes ambientais pode ter relação com aumentos na atividade de defesas antioxidantes, aumentos na atividade da ALDH ou excreção do MDA na água. Assim, os lambaris foram expostos a misturas de metais (cádmio e cobre) nas concentrações 40 e 100 μg/L e a biodiesel B5 nas concentrações de 0,001, 0,01 e 0,1 mL/L para verificar a relação entre MDA e as enzimas antioxidantes, em amostras de brânquia e fígado. Um segundo experimento, injetando MDA nos espécimes foi realizado, nestes organismos, foram injetados intraperitonealmente doses de 10 mg/kg e 100 mg/kg de MDA com coleta do material biológico após 5 dias para avaliar o efeito do MDA no fígado e na brânquia do lambari. Um terceiro experimento foi realizado para avaliar a metabolização do MDA em brânquia e fígado e sangue com coleta de material biológico e água nos tempos zero (logo após receber a dose), 1 e 12 horas. Nestes experimentos a metabolização do MDA foi observada pela atividade da enzima aldeído desidrogenase (ALDH) e as enzimas antioxidantes catalase (CAT), glutationa peroxidase (GPx), glicose – 6- fosfato- desidrogenase (G6PDH) e a de biotransformação glutationa S-transferase (GST), peróxidos lipídicos (FOX), níveis de glutationa total (GSH-t) e ensaio do MDA. Por fim foi realizado um experimento in vitro para avaliar o efeito do MDA nas enzimas (CAT, GPx, G6PDH, GST e ALDH). Nossos resultados mostraram que o MDA tem vias de metabolização e que o aumento das enzimas antioxidantes não é responsável por sua diminuição. Sugerimos que o B5 foi capaz de induzir a atividade da ALDH e esta diminuiu a quantidade de MDA nos dois grupos de maior concentração de B5. O MDA não foi capaz de induzir a atividade da ALDH, entretanto observamos uma forte correlação entre o MDA e a ALDH. O experimento in vitro mostrou que em concentrações elevadas o MDA pode até mesmo inibir a atividade da ALDH, sugerindo que esta enzima atue na manutenção dos níveis basais deste aldeído. Por fim, o trabalho mostrou que o lambari foi capaz de eliminar o MDA em excesso por meio da excreção, fortalecendo nossa hipótese de que o organismo dos peixes utiliza vias de excreção e da ALDH para eliminar o excesso deste aldeído toxico produzido na PL por estressores ambientais / Among the adverse effects of exposure to pollutants in aquatic animals, we can highlight oxidative stress, which can be caused due to an exacerbated production of reactive oxygen species along with a cascade of biochemical events. During this cascade, one of oxidative consequences we can observe is called lipid peroxidation (LPO) with its main product malondialdehyde (MDA). Thus, although the increase in MDA levels is related to intoxication by pollutants, some studies have shown a decrease in MDA levels in aquatic organisms exposed to pollutants, even with significant improvment in antioxidant enzymes. Thus, this study aimed to assess the relationship among the reduced MDA levels in Astyanax altiparanae fish exposed to environmental contaminants, and increased antioxidant defenses and aldehyde dehydrogenase (ALDH) activity, or excretion of MDA in the water. In this way, the fishes were exposed to mixtures of metals (cadmium or copper) at concentrations of 40 g/L and 100 g/L and to B5 biodiesel in concentrations of 0.001 mL/L, 0.01 mL/L and 0.1 mL/L in order to verify the relation between MDA and antioxidant enzymes in the liver, and gill samples. We performed a second experiment by injecting MDA in the fish specimens. We intraperitoneally injected doses of 10 mg/kg and 100 mg/kg of MDA. After 5 days, we collected the liver and gill in order to evaluate the effect of MDA in the fishes. A third experiment was conducted to investigate MDA metabolization in blood, gill and liver samples, through collection of biological material and water at zero time (shortly after receiving the same intraperitoneal injections as in the second experiment), 1 and 12 hours after the injections. In these experiments, the MDA metabolization was monitored by the activity of ALDH and by the antioxidant enzymes such as catalase (CAT), glutathione peroxidase (GPx), glucose-6-phosphate dehydrogenase (G6PDH) and glutathione-S-transferase biotransformation (GST), lipid peroxides by ferrous ion oxidation xylenol orange (FOX) assay, the total glutathione (GSH-t) and MDA assay. Finally, an experiment was conducted in vitro to evaluate the effect of enzymes on MDA (CAT, GPx, G6PDH, GST and ALDH). Our results showed that the MDA levels have metabolizing pathways and increased antioxidant enzymes are not responsible for their decrease. We suggest that the B5 was able to induce the ALDH activity, Moreover, ALDH was related to reduced amount of MDA in both groups of higher B5 concentration. The MDA was not able to induce the activity of ALDH, despite we found a strong correlation between the MDA levels and ALDH activity. In the in vitro experiment, we observed that high concentrations of MDA could even inhibit the activity of ALDH, suggesting that this enzyme acts in the maintenance of basal levels of this aldehyde. Finally, the study showed that the Astyanax altiparanae have been able to eliminate the MDA excess by excretion. This fact reinforces our hypothesis that the fish uses excretion routes and ALDH to eliminate excess of this toxic aldehyde produced during LPO cased by stressors environmental.