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Background: Amphotericin B (AmB) is a commonly utilized antifungal agent, which is also recommended for the treatment of certain neglected tropical diseases, including leishmaniasis. However, its clinical application is constrained because of its poor oral bioavailability and adverse effects, prompting the investigation of alternative drug delivery systems. Polymeric nanoparticles (PNPs) have gained attention as a potential drug delivery vehicle, providing advantages such as sustained release and enhanced bioavailability, and could have potential as AmB carriers. However, concerns persist regarding nanomaterials’ toxicity, requiring more studies. Zebrafish (Danio rerio) embryos were used as a valuable model for toxicity testing, especially because of their genetic similarity to humans and standardized developmental assessments. Methods: In this study, we produced and characterized AmB loaded and non-loaded PNPs by nanoprecipitation, dynamic light scattering, transmission electron microscopy, atomic force microscopy and spectroscopy. Afterwards, we verified their toxicity through in vitro MTT assays in three cell lines (HEK293, HepG2, and J774 A1) and in vivo tests with zebrafish embryos. Results: In both trials, it was noted that nanoencapsulation of the drug led to increased toxicity when compared to non-encapsulated AmB, possibly indicating that they penetrated the embryo’s chorion. Nevertheless, it was demonstrated that the polymers used are safe and they are not the cause of toxicity, neither are the nanostructures per se. Conclusions: Therefore, it is believed that the objective of improving the bioavailability of AmB may have been achieved, and the observed toxicity was probably linked to AmB’s ability to destabilize cell membranes.

Introdução: O uso de animais de laboratório é fundamental em áreas em que ainda não podem ser substituídos na totalidade, como a toxicologia. Em estudos que se utilizam, para fins de comparação, apenas dados fornecidos pelos laboratórios de análises clínicas, na tentativa de reduzir o número de animais de um experimento, arrisca-se utilizar informações que não correspondem à realidade. Objetivo: Debater o uso de grupo controle em experimentos com animais. Método: Este artigo comparou valores hematológicos e bioquímicos de ratos da linhagem Wistar, obtidos em três biotérios de criação de diferentes estados brasileiros, com os resultados de animais provindos do Instituto de Ciência e Tecnologia em Biomodelos da Fundação Oswaldo Cruz, Rio de Janeiro, objetivando a discussão acerca da tomada de decisão sobre a inclusão de grupo controle em ensaios de toxicidade aguda oral. Resultados: Poucos foram os parâmetros que não apresentaram diferenças estatísticas, tais como: hemácia em fêmeas (duas referências), hemoglobina em fêmeas (uma referência) e machos (uma referência), hematócrito nos machos (duas referências) e hemoglobina corpuscular média nas fêmeas (duas referências), leucócitos nos machos (uma referência), creatinina e alanina aminotransferase (ALT) em todas as fêmeas. Conclusões: O uso do grupo controle se faz necessário quando valores analisados preliminarmente apresentam-se discrepantes daqueles tidos como referenciais da espécie.

Introduction: Heparin is a drug that has anticoagulant activity, binding to antithrombin and accelerating the rate of inhibition of several proteases involved in the coagulation process. In the 2000s, the world market faced a troubled period regarding heparins after reports of allergic reactions and deaths caused by its use, requiring more rigorous quality control. Objective: The main goal of this work was to perform quality control of unfractionated sodium heparins of porcine origin commercialized in Brazil and heparin raw material on a dry basis, of both porcine and bovine origin, through potency assays. Method: Sixty-four samples of the final product (commercialized) were analyzed: 39 of brand A and 25 of brand B, and six samples of raw materials. Samples were assayed through anti-factor Xa and anti-factor IIa, according to United States Pharmacopeia (USP), and coagulation assay, described in the 5th edition of Brazilian Pharmacopeia (BP). Results: In the present study, 40 heparin samples were approved in all potency assays, while 24 samples were non-approved, 23 of brand A and one of brand B. All samples of porcine-origin raw materials were considered approved, while the three of bovine origin showed lower potency. Conclusions: Almost all non-approved samples presented potency above 110%, which may represent a bleeding risk for patients. Thus, it is necessary to monitor the quality control of heparins and assess the clinical condition of patients undergoing their use to identify and reduce risks and safeguard public health.