Effects of bisphenol A and S on blood coagulation: in vivo, in vitro and in silico approaches in toxicodynamic.

Bisphenol A (BPA) is a well-known endocrine disruptor with several effects on mammalian systems and has been linked to diseases, such as cancer. Bisphenol S (BPS) emerged as a likely alternative to BPA in industrial production. Despite being well studied and exhibiting BPA-like toxic capacity, many effects are still being elucidated. The blood coagulation system is well controlled in an effort to minimize blood loss. To our knowledge, no study reported actions of bisphenols in this system. The aim of this work was to evaluate the effects of bisphenols on blood coagulation. Zebrafish were used to measure bleeding time. To assess possible mechanisms, platelet-rich plasma was incubated with both bisphenols in the presence of arachidonic acid. Prothrombin time (PT) and activated partial thromboplastin time (APTT) assays were performed in the presence of BPA and BPS. Alignment of human factor VII sequence was compared to zebrafish and docking simulations performed with FVIIa and bisphenols. An extended time was observed in BPA-treated but not BPS-treated animals in bleeding time; in PT, bisphenols showed no effect. APTT was increased in the highest concentration of bisphenols, with no effects in platelet aggregation, indicating interference with factor VII. Protein alignment showed that both proteins have well conserved residues, as those being required for interaction of FVIIa-BPA and FVIIa-BPS complexes, as shown in molecular docking. Taken together, these data show BPA and BPS as capable of interfering with the coagulation process via FVIIa.

Isolation, fractionation and anticoagulant activity of a sulfated galactan extracted from the green algae Penicillus capitatus / Isolamento, fracionamento e atividade anticoagulante da galactana sulfatada extraída da alga verde Penicillus capitatus

ABSTRACT: Marine algae are natural sources of macromolecules known as sulfated polysaccharides. This class of compounds has attracted the interest of Pharmaceutical Sciences due to its pharmacological anticoagulant, antiplatelet and antithrombotic properties. Therefore, this study evaluated the anticoagulant potential of sulfated polysaccharides extracted from the algae Penicillus capitatus. The extracted sulfated polysaccharides were purified, partially characterized and their anticoagulant activity was evaluated. The extraction process followed by ethanol precipitation resulted in five fractions. Among the analyzed fractions, F44 contained highest concentration of sulfated polysaccharides. After the purified fraction F23, F44 displayed in vitro anticoagulant activity in a time testing for activated partial thromboplastin time and prothrombin time. The preferential mechanism effect was based on interactions between thrombin and factor Xa. Additional studies on structure pharmacological are required to test the viability of the use of sulfated polysaccharides as therapeutic agents.

RESUMO: As algas marinhas são fontes naturais de macromoléculas conhecidas como polissacarídeos sulfatados. Esta classe de compostos atraiu o interesse das Ciências Farmacêuticas devido às suas propriedades farmacológicas como anticoagulante, antiplaquetária e antitrombótica. Portanto, este estudo tem como objetivo avaliar o potencial anticoagulante de polissacarídeos sulfatados extraídos de algas de Penicillus capitatus. Os polissacarídeos sulfatados extraídos foram purificados, parcialmente caracterizados e sua atividade anticoagulante foi avaliada. O processo de extração seguido pela precipitação com etanol resultou em cinco frações. Entre as frações analisadas, F44 foi a maior concentração de polissacarídeos sulfatados. Após a purificação, as frações F23 e F44 mostraram atividade anticoagulante in vitro em um teste de tempo de tromboplastina parcialmente ativada e tempo de protrombina. Seu mecanismo preferencial é baseado nas interações entre trombina e fator Xa. Estudos adicionais sobre a estrutura farmacológica são necessários para testar a viabilidade do uso como agente terapêutico.