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Advisor(s)
Abstract(s)
Atualmente, devido ao massivo uso comum de plásticos com diferentes formas e tamanhos, é inevitável a entrada no organismo de nanoplásticos (NPs) e aditivos tal como plasticizantes como Bisfenol A (BPA), de forma independente ou em misturas. Existe evidência científica da exposição via oral e de absorção em tecidos gástricos destes poluentes. Isto, em conjunção com a capacidade de NPs de atuar como vetor de outros, leva a que o potencial tóxico seja bastante elevado. Como tal, é necessário avaliar o impacto a nível celular e sub-celular, prevendo as consequências a nível de tecido, órgão e organismo a longo prazo. O objetivo desse estudo in vitro, foi investigar os efeitos citotóxicos, e genotóxicos, da exposição individual e combinada de BPA e nanopartículas de polistireno (PS-NPs), na linha celular gástrica GP202. Foram selecionadas concentrações ambientais relevantes e previamente testadas em literatura, para as PS-NPs - 20, 100 e 200 μg/mL e para o BPA - 0,04, 0,1 e 1 ng/mL, sendo que 0,04 ng/mL, é o valor de referência proposta pela EFSA. A citotoxicidade foi avaliada através do ensaio de Cell Titer- Blue® e a genotoxicidade, nomeadamente danos no DNA, foi investigada através do ensaio de micronúcleo por bloqueio de citocineses (CBMN), de acordo com a Guideline 487 da OCDE. Os resultados apontam que a citotoxicidade não é afetada pelas exposições individuais ou combinadas de PS-NPs e BPA. Relativamente a genotoxicidade, verificou-se um aumento estatisticamente significativo de todos os parâmetros investigados: micronúcleos (MN), pontes nucleoplasmáticas (NBPs) e protusões nucleares (NBUDs), nas exposições combinadas nas concentrações mais elevadas (200 μg/mL de PS-NPs + 1 ng/mL de BPA) em comparação com o controlo negativo. Os resultados desta investigação justificam a necessidade de realizar mais estudos com exposições combinadas de NPs e BPA, de forma a desenvolver, realizar e avaliar os riscos de misturas químicas.
ABSTRACT - Nowadays, due to the massive use of plastics of different shapes and sizes, it is inevitable that nano plastics (NPs) and their additives such as plasticizers as Bisphenol A (BPA), enter the body as single substances or mostly as a mixture. There is scientific evidence of oral exposure and absorption of these substances in gastric tissues. This, in conjunction with the NP's ability to act as a vector for other pollutants, results in a quite high toxic potential. As such, there is a need to assess the impact at the cellular and sub-cellular levels, predicting the consequences on tissue, organ, and organism levels in the long term. The aim of this in vitro study was to investigate the cytotoxic and genotoxic effects of the individual and combined exposure of BPA and polystyrene (PS)-NPs in the GP202 gastric cell line. Environmental relevant concentrations previously tested in literature were selected, for PS-NPs – 20, 100, and 200 μg/mL and for BPA – 0,04, 0,1 e 1 ng/mL, and 0,04 ng/mL, which is the reference value proposed by EFSA. Cytotoxicity was assessed by Cell Titer- Blue® assay and genotoxicity by cytokinesis-block micronucleus assay, following OECD Guideline 487. The results indicate that cytotoxicity is not affected by individual or combined exposures of PS-NPs and BPA. Regarding genotoxicity, it was observed that all the endpoints – micronucleus, nucleoplasmic bridges, and nuclear buds – were statistically significantly increased in the worst-case-scenario of combined exposure (200 μg/mL PS NPs + 1 ng/mL BPA) compared with the negative control. These results justify the need for further studies with combined exposures of NPs and BPA to develop, carry out, and evaluate the safety risks of chemical mixtures.
ABSTRACT - Nowadays, due to the massive use of plastics of different shapes and sizes, it is inevitable that nano plastics (NPs) and their additives such as plasticizers as Bisphenol A (BPA), enter the body as single substances or mostly as a mixture. There is scientific evidence of oral exposure and absorption of these substances in gastric tissues. This, in conjunction with the NP's ability to act as a vector for other pollutants, results in a quite high toxic potential. As such, there is a need to assess the impact at the cellular and sub-cellular levels, predicting the consequences on tissue, organ, and organism levels in the long term. The aim of this in vitro study was to investigate the cytotoxic and genotoxic effects of the individual and combined exposure of BPA and polystyrene (PS)-NPs in the GP202 gastric cell line. Environmental relevant concentrations previously tested in literature were selected, for PS-NPs – 20, 100, and 200 μg/mL and for BPA – 0,04, 0,1 e 1 ng/mL, and 0,04 ng/mL, which is the reference value proposed by EFSA. Cytotoxicity was assessed by Cell Titer- Blue® assay and genotoxicity by cytokinesis-block micronucleus assay, following OECD Guideline 487. The results indicate that cytotoxicity is not affected by individual or combined exposures of PS-NPs and BPA. Regarding genotoxicity, it was observed that all the endpoints – micronucleus, nucleoplasmic bridges, and nuclear buds – were statistically significantly increased in the worst-case-scenario of combined exposure (200 μg/mL PS NPs + 1 ng/mL BPA) compared with the negative control. These results justify the need for further studies with combined exposures of NPs and BPA to develop, carry out, and evaluate the safety risks of chemical mixtures.
Description
Este projeto recebeu financiamento do concurso de Investigação, Desenvolvimento, Inovação e Criação Artística (IDI&CA) com a referência IPL/2021/PLASCOGEN_ESTeSL.
Mestrado em Tecnologias Clínico-laboratoriais
Mestrado em Tecnologias Clínico-laboratoriais
Keywords
Nanopartículas de poliestireno Bisfenol A Células gástricas GP202 Citotoxicidade Genotoxicidade In vitro Exposição combinada Polystyrene nanoparticles Bisphenol A Gastric cell GP202 Citotoxicity Genotoxicity Combined exposures IPL/2021/PLASCOGEN_ESTeSL
Citation
Brito CB. Efeitos citotóxicos genotóxicos da exposição individual e combinada de nanopartículas de poliestireno e bisfenol A, na linha celular GP 202: um estudo piloto in vitro [dissertation]. Lisboa: Escola Superior de Tecnologia da Saúde de Lisboa/Instituto Politécnico de Lisboa; 2023.
Publisher
Instituto Politécnico de Lisboa, Escola Superior de Tecnologia da Saúde de Lisboa