Cytotoxicity assays to evaluate tannery effluents treated by photoelectrooxidation.

The advanced oxidation process (AOP) is used to increase the treatment efficiency of effluents however, it is necessary to compare the toxicity of treated and untreated effluents to evaluate if the decontamination process does not cause any biological harm. Cultured cells have been previously used to assess the genotoxic and cytotoxic potential of various compounds. Hence, the aim of this work was to assess the applicability of cytotoxicity assays to evaluate the toxicity related to the AOP treatment. Samples of an industrial effluent were collected after their treatment by a conventional method. Cytotoxicity of standard and AOP treated effluents was assessed in CRIB and HEp-2 cell line using the MTT and neutral red assays. We observed decrease at cell viability in the both assays (50% MTT and 13% NRU) when cells were exposed to the AOP treatment in the highest concentration. Thus, cytotoxic assays in cultured cells can be explored as an useful method to evaluate toxicity as well as to optimize effluents treatment process.

Cytotoxicity assays to evaluate tannery effluents treated by photoelectrooxidation / Ensaios de citotoxicidade na avaliação de efluentes de curtume tratados por fotoeletrooxidação

The advanced oxidation process (AOP) is used to increase the treatment efficiency of effluents however, it is necessary to compare the toxicity of treated and untreated effluents to evaluate if the decontamination process does not cause any biological harm. Cultured cells have been previously used to assess the genotoxic and cytotoxic potential of various compounds. Hence, the aim of this work was to assess the applicability of cytotoxicity assays to evaluate the toxicity related to the AOP treatment. Samples of an industrial effluent were collected after their treatment by a conventional method. Cytotoxicity of standard and AOP treated effluents was assessed in CRIB and HEp-2 cell line using the MTT and neutral red assays. We observed decrease at cell viability in the both assays (50% MTT and 13% NRU) when cells were exposed to the AOP treatment in the highest concentration. Thus, cytotoxic assays in cultured cells can be explored as an useful method to evaluate toxicity as well as to optimize effluents treatment process.

Resumo O processo de oxidação avançada (POA) tem sido usado para aumentar a eficiência do tratamento de efluentes; no entanto, é necessário comparar a toxicidade de efluentes tratados e não tratados para avaliar se o processo de descontaminação não é capaz de causar algum risco biológico. Cultivos celulares têm sido utilizados para avaliar o potencial genotóxico e citotóxico de vários compostos. Assim, o objetivo deste trabalho foi avaliar a aplicabilidade de ensaios de citotoxicidade para avaliar a toxicidade relacionada ao tratamento com POA. As amostras de um efluente industrial foram recolhidas após o tratamento por um método convencional. A citotoxicidade dos efluentes padrão e tratado com POA foi avaliada nas linhagens celulares CRIB e HEp-2 usando os ensaios do MTT e do vermelho neutro. Observou-se diminuição da viabilidade celular em ambos os ensaios (50% MTT e 13% VN) quando as células foram expostas à concentração mais elevada do efluente tratado com POA. Assim, os ensaios de citotoxicidade em cultivos celulares podem ser explorados como um método útil para avaliar a toxicidade, bem como para otimizar os processos de tratamento de efluentes.

Cytotoxicity assays to evaluate tannery effluents treated by photoelectrooxidation

The advanced oxidation process (AOP) is used to increase the treatment efficiency of effluents however, it is necessary to compare the toxicity of treated and untreated effluents to evaluate if the decontamination process does not cause any biological harm. Cultured cells have been previously used to assess the genotoxic and cytotoxic potential of various compounds. Hence, the aim of this work was to assess the applicability of cytotoxicity assays to evaluate the toxicity related to the AOP treatment. Samples of an industrial effluent were collected after their treatment by a conventional method. Cytotoxicity of standard and AOP treated effluents was assessed in CRIB and HEp-2 cell line using the MTT and neutral red assays. We observed decrease at cell viability in the both assays (50% MTT and 13% NRU) when cells were exposed to the AOP treatment in the highest concentration. Thus, cytotoxic assays in cultured cells can be explored as an useful method to evaluate toxicity as well as to optimize effluents treatment process.

Resumo O processo de oxidação avançada (POA) tem sido usado para aumentar a eficiência do tratamento de efluentes; no entanto, é necessário comparar a toxicidade de efluentes tratados e não tratados para avaliar se o processo de descontaminação não é capaz de causar algum risco biológico. Cultivos celulares têm sido utilizados para avaliar o potencial genotóxico e citotóxico de vários compostos. Assim, o objetivo deste trabalho foi avaliar a aplicabilidade de ensaios de citotoxicidade para avaliar a toxicidade relacionada ao tratamento com POA. As amostras de um efluente industrial foram recolhidas após o tratamento por um método convencional. A citotoxicidade dos efluentes padrão e tratado com POA foi avaliada nas linhagens celulares CRIB e HEp-2 usando os ensaios do MTT e do vermelho neutro. Observou-se diminuição da viabilidade celular em ambos os ensaios (50% MTT e 13% VN) quando as células foram expostas à concentração mais elevada do efluente tratado com POA. Assim, os ensaios de citotoxicidade em cultivos celulares podem ser explorados como um método útil para avaliar a toxicidade, bem como para otimizar os processos de tratamento de efluentes.

Functional regeneration in a rat Parkinson's model after intrastriatal grafts of glial cell line-derived neurotrophic factor and transforming growth factor beta1-expressing extra-adrenal chromaffin cells of the Zuckerkandl's organ.

Intrabrain transplantation of chromaffin cell aggregates of the Zuckerkandl's organ, an extra-adrenal paraganglion that has never been tested for antiparkinsonian treatment, induced gradual improvement of functional deficits in parkinsonian rats. These beneficial effects were related to long survival of grafted cells, striatal reinnervation, and enhancement of dopamine levels in grafted striatum. Grafted cells were not dopaminergics, but they expressed glial cell line-derived neurotrophic factor (GDNF) and transforming growth factor-beta(1). These factors were detected in the host striatal tissue, indicating that chromaffin cells secreted them after grafting. Because glial cell line-derived neurotrophic factor possesses neurorestorative properties over dopaminergic neurons, and transforming growth factor-beta(1) is a cofactor that potentiates the neurotrophic actions of GDNF, functional regeneration was likely caused by the chronic trophic action of neurotrophic factors delivered by long-surviving grafted cells. This work should stimulate research on the clinical applicability of transplants of the Zuckerkandl's organ in Parkinson's disease.