RESUMEN
The main goal of this study was to perform an ecotoxicological profiling of terrestrial and aquatic cyanobacterial strains found in different soils or in toxic cyanobacterial blooms in Vojvodina region, Serbia, using the effect-directed analysis (EDA) approach. The applied procedure was based on a series of in vitro or small-scale bioassays covering multiple endpoints in combination with advanced chemical analytical protocols. Non-selective and non-target preparation techniques were used for the extraction of a broad range of chemical compounds present in three terrestrial (Anabaena C2, Anabaena C5, Nostoc S8) and three aquatic (Nostoc Z1, Phormidium Z2, Oscillatoria K3) strains. Ecotoxicological endpoints addressed included evaluation of the fish cytotoxicity in vitro (acute toxicity), algal growth inhibition (chronic toxicity), and interaction with cellular detoxification mechanisms. All cyanobacterial strains tested in the 1st tier EDA showed significant effects in terms of chronic toxicity and interaction with cellular detoxification. Three major fractions of different polarities were further tested in the 2nd tier, using bioassays which showed the strongest response: induction of CYP1A1 biotransformation enzyme and inhibition of zebrafish organic anion (Oatp1d1) and cation (Oct1) uptake transporters. Oscillatoria K3 strain was selected for a more detailed 3rd tier EDA, and the obtained results revealed that positive sub-fractions possess polar anion and cation compounds that are reactive to both uptake transporters, and compounds responsible for the strongest effects have a pronounced lipophilic character. Apart from lipophilic non-polar compounds that represent typical phase I substrates, sub-fractions that contained polar substances are also shown to significantly induce CYP1A1.
Asunto(s)
Ecotoxicología , Pruebas de Toxicidad/métodos , Animales , Bioensayo , Cianobacterias , Serbia , Pez CebraRESUMEN
Caulerpa taxifolia is a marine alga of tropical and subtropical distribution and a well-known invasive species in several temperate regions. Its invasiveness mainly stems from the production of secondary metabolites, some of which are toxic or repellent substances. In this study we investigated the possible inhibitory effects of C. taxifolia secondary metabolites on the activity of two zebrafish (Danio rerio) uptake transporters that transport organic anions (Oatp1d1) and cations (Oct1). Both transporters were transiently transfected and overexpressed in human embryonic kidney HEK293T cells. Transport activity assays using lucifer yellow (LY) and 4-(4-(dimethylamino)styryl)-N-methylpyridinium iodide (ASP+) as model substrates were applied for the determination of Oatp1d1 and Oct1 interactors. A two-step Effect-Directed Analysis (EDA) procedure was applied for the separation and identification of compounds. We identified caulerpenyne (CYN) as the major metabolite in C. taxifolia and reveal its potent inhibitory effect towards zebrafish Oatp1d1 as well as weak effect on zebrafish Oct1 transport. The observed effect was confirmed by testing CYN purified from C. taxifolia, resulting in an IC50 of 17.97 µM, and a weak CYN interaction was also determined for the zebrafish Oct1 transporter. Finally, using Michaelis-Menten kinetics experiments, we identified CYN as a non-competitive inhibitor of the zebrafish Oatp1d1. In conclusion, this study describes a novel mechanism of biological activity in C. taxifolia, shows that CYN was a potent non-competitive inhibitor of zebrafish Oatp1d1, and demonstrates that EDA can be reliably used for characterization of environmentally relevant complex biological samples.
Asunto(s)
Caulerpa/metabolismo , Proteínas de Transporte de Membrana/metabolismo , Sesquiterpenos/toxicidad , Proteínas de Pez Cebra/antagonistas & inhibidores , Animales , Células HEK293 , Humanos , Especies Introducidas , Proteínas de Transporte de Membrana/genética , Sesquiterpenos/metabolismo , Pez Cebra , Proteínas de Pez Cebra/genética , Proteínas de Pez Cebra/metabolismoRESUMEN
El presente trabajo busca, a través de las Representaciones Sociales, comprender las razones por las que el Estado Plurinacional de Bolivia confrontó una grave crisis política después de las elecciones realizadas el 20 de octubre de 2019. Crisis política que obligó a anular las elecciones, elegir una nueva Corte Nacional Electoral y llamar a nuevas elecciones. El trabajo postula que para entender esta problemática, es necesario revisar las Representaciones Sociales de los grupos que conforman el Estado Plurinacional de Bolivia, pues estas generan visiones diferentes de país, que podrían estar influyendo en la vida política del mismo.
This work seeks, through the Social Representations, understand the reasons why the Plurinational State of Bolivia faced a serious political crisis after the elections held on October 20, 2019. Political crisis forced the cancel out of the elections, chose new members of his electoral college and called for new elections. The work point out that in order to understand this problem, it is necessary to review the Social Representations of different groups, that make up the Plurinational State of Bolivia; these different visions of the country, may be influencing his political life.
O presente trabalho procura, por meio das Representações Sociais, entender as razões pelas quais o Estado Plurinacional da Bolívia enfrentou uma grave crise política após as eleições realizadas em 20 de outubro de 2019. Crise política que forçou a anulação das eleições, escolhendo um novo Tribunal Nacional Eleitoral e convocar novas eleições. O trabalho postula que, para entender esse problema, é necessário rever as Representações Sociais dos grupos que compõem o Estado Plurinacional da Bolívia, uma vez que geram visões diferentes do país, o que pode estar influenciando sua vida política.
RESUMEN
Conocer la percepción de riesgo ante los desastres, que tienen los habitantes de la ciudad de La Paz; conocer los factores psicosociales que impulsan a los habitantes de zonas de alto riesgo a vivir en las mismas
