Encapsulation of benznidazole in nanostructured lipid carriers and increased trypanocidal activity in a resistant Trypanosoma cruzi strain

Abstract Chagas disease is a neglected parasitic disease caused by Trypanosoma cruzi, whose treatment has remained unsatisfactory for over 50 years, given that it is limited to two drugs. Benznidazole (BZN) is an efficient antichagasic drug used as the first choice, although its poor water-solubility, irregular oral absorption, low efficacy in the chronic phase, and various associated adverse effects are limiting factors for treatment. Incorporating drugs with such characteristics into nanostructured lipid carriers (NLC) is a promising alternative to overcome these limiting obstacles, enhancing drug efficacy and bioavailability while reducing toxicity. Therefore, this study proposed NLC-BZN formulations in different compositions prepared by hot-melt homogenization followed by ultrasound, and the optimized formulation was characterized by FTIR, DRX, DSC, and thermogravimetry. Biological activities included in vitro membrane toxicity (red blood cells), fibroblast cell cytotoxicity, and trypanocidal activity against epimastigotes of the Colombian strain of T. cruzi. The optimized NLC-BZN had a small size (110 nm), negative zeta potential (-18.0 mV), and high encapsulation (1.64% of drug loading), as shown by infrared spectroscopy, X-ray diffraction, and thermal analysis. The NLC-BZN also promoted lower in vitro membrane toxicity (<3% hemolysis), and 50% cytotoxic concentration (CC50) for NLC-BZN in L929 fibroblast cells (110.7 µg/mL) was twice the value as the free BZN (51.3 µg/mL). Our findings showed that the NLC-BZN had higher trypanocidal activity than free BZN against the epimastigotes of the resistant Colombian strain, and this novel NLC-BZN formulation proved to be a promising tool in treating Chagas disease and considered suitable for oral and parenteral administration

Phytochemical screening and evaluation of the toxic potential of ethanolic extract and fractions of Ageratum fastigiatum / Triagem fitoquímica e avaliação do potencial tóxico do extrato etanólico e frações de Ageratum fastigiatum / Cribado fitoquímico y evaluación del potencial tóxico del extracto etanólico y fracciones de Ageratum fastigiatum

SUMMARY Introduction: Ethanolic and hydroalcoholic extracts of Ageratum fastigiatum are used in folk medicine as anti-inflammatory and analgesic agents. Aim: To evaluate toxicity in Artemia salina and in the cells of the connective tissue of mice (L929). Methodology: The extract was partitioned and its hexane, dichloromethane and hydroalcoholic phases were submitted to the same test. The phytochemical screening of the phases of the extract was performed using tests aimed at the detection of secondary metabolites and GC-MS. Regarding A. salina, the hydroalcoholic phase exhibited the highest toxicity (LC50, 1.33 mg/mL) and the crude ethanolic extract was the least toxic (LC50, 4.81 mg/mL). In the assay of L929 cells, the dichloromethane phase was the most toxic (95.48% reduction in cell viability; LC50, 11.39 µg/mL), while the hydroalcoholic phase was the least toxic (cell death percentage, 55.67-19.38 %; LC50, 174.20 µg/mL). Result: The phytochemical study indicated the presence of alkaloids, coumarins, saponins, triterpenes/steroids and tannins. The GC-MS analysis identified the presence of terpenoids and a lycopsamine derivative (a pyrrolizidine alkaloid). Conclusion: These results suggest that the ethanolic extract of A. fastigiatum had constituents (i.e., phenolic compounds) that corroborate its use in folk medicine as an anti-inflammatory agent. However, the toxicity detected and the presence of 3'-acetyl lycopsamine (a chemotaxonomic marker of the genus that is hepatotoxic) indicates that this medicinal plant should be used with caution.

RESUMO Introdução: Os extratos etanólico e hidroalcoólico de Ageratum fastigiatum são usados na medicina popular como agentes antiinflamatório e analgésico. Objetivo: Avalidar quanto à sua toxicidade em Artemia salina e nas células do tecido conjuntivo de camundongos (L929). Metodologia: O extrato foi particionado e suas fases hexânica, diclorometânica e hidroalcoólica foram submetidas ao mesmo teste. A triagem fitoquímica das fases do extrato foi realizada por meio de testes visando a detecção de classes de metabólitos secundários e GC-MS. Resultados: Em relação a A. salina, a fase hidroalcoólica apresentou a maior toxicidade (CL50, 1,33 mg/mL) e o extrato etanólico bruto foi o menos tóxico (CL50_ 4,81 mg/mL). No ensaio de células L929, a fase de diclorometânica foi a mais tóxica (95,48% de redução na viabilidade celular; LC50, 11,39 µg/mL), enquanto a fase hidroalcoólica foi a menos tóxica (porcentagem de morte celular, 55,67-19,38 %; LC50, 174,20 µg/mL). O estudo fitoquímico indicou a provável presença de alcalóides, cumarinas, saponinas, triterpenos/ esteróides e taninos. A análise por GC-MS identificou a presença de terpenóides e um derivado de licopsamina (alcalóide pirrolizidínico). Conclusão: Esses resultados sugerem que o extrato etanólico de A. fastigiatum possui constituintes (ou seja, compostos fenólicos) que corroboram seu uso na medicina popular como agente antiinflamatório. No entanto, a toxicidade detectada e a presença da 3'-acetil licopsamina (um marcador quimiotaxonômico do gênero, que é hepatotóxico) indicam que essa planta medicinal deve ser usada com cautela.

RESUMEN Introducción: Los extractos etanólico e hidroalcohólico de Ageratum fastigiatum se utilizan en la medicina popular como agentes antiinflamatorios y analgésicos. Objetivo: Evaluar la toxicidad en artemia salina y en las células del tejido conectivo de ratones (L929). Metodología: El extracto se fraccionó y se sometieron a la misma prueba sus fases hexano, diclorometano e hidroalcohólica. El tamizaje fitoquímico de las fases del extracto se realizó mediante pruebas dirigidas a la detección de metabolitos secundarios y GC-MS. En cuanto a A. salina, la fase hidroalcohólica presentó la mayor toxicidad (CL50, 1,33 mg/mL) y el extracto etanólico crudo fue el menos tóxico (CL50, 4,81 mg/mL). En el ensayo de células L929, la fase de diclorometano fue la más tóxica (95,48% de reducción de la viabilidad celular; CL50, 11,39 µg/mL), mientras que la fase hidroalcohólica fue la menos tóxica (porcentaje de muerte celular, 55,67-19,38 %; CL50, 174,20 µg/mL). Resultado: El estudio fitoquímico indicó la probable presencia de alcaloides, cumarinas, saponinas, triterpenos/esteroides y taninos. El análisis GC-MS identificó la presencia de terpenoides y un derivado de licopsamina (un alcaloide de pirrolizidina). Conclusión: Estos resultados sugieren que el extracto etanólico de A. fastigiatum tenía constituyentes (es decir, compuestos fenólicos) que corroboran su uso en la medicina popular como agente antiinflamatorio. Sin embargo, la toxicidad detectada y la presencia de 3'-acetil licopsamina (un marcador quimiotaxonómico del género que es hepatotóxico) indica que esta planta medicinal debe utilizarse con precaución.

Nanonization techniques to overcome poor water-solubility with drugs.

INTRODUCTION: Most drugs used in therapy have low water-solubility, a factor that could reduce their dissolution rate and oral bioavailability, representing a challenge in pharmaceutical development. Nanonization of drugs is the reduction of particles to nanoscale, increasing the surface area and consequently the saturation solubility and dissolution rate and resulting in higher bioavailability. AREAS COVERED: This review provides an overview of the consequences of the poor water-solubility and the main strategies applied to increase the solubility of poorly water-soluble drugs. The relationship between the biopharmaceutical classification system and the solubilization process of the drug is also considered. Finally, it includes how drug nanoparticles and nanocarriers, especially lipid-based nanosystems, can overcome these challenges and which of these approaches are already available on the market. EXPERT OPINION: Due to the growing importance of nanomedicines, especially for applications in poorly water-soluble drugs, it is important to clearly establish the specifications and quality criteria for nanonized drugs to ensure the quality and safety of nanoparticles.

Medicamentos genéricos no Brasil: panorama histórico e legislação / Generic drugs in Brazil: historical overview and legislation

A política de medicamentos genéricos foi implantada no Brasil em 1999 com o objetivo de estimular a concorrência comercial, melhorar a qualidade dos medicamentos e facilitar o acesso da população ao tratamento medicamentoso. O processo de implementação dessa política permitiu a introdução e a discussão de conceitos nunca antes utilizados para o registro de medicamentos no Brasil: biodisponibilidade, bioequivalência, equivalência farmacêutica, medicamentos genéricos, sistema de classificação biofarmacêutica e bioisenção. Este artigo apresenta a definição desses conceitos no contexto das leis brasileiras e oferece uma descrição histórica e cronológica da implementação da política de genéricos no Brasil, listando ainda as resoluções que atualmente estão em vigor. Os resultados contribuem para a compreensão do processo e facilitam a busca e a identificação de ensaios necessários para satisfazer os critérios legais.

The Brazilian generic drugs policy was implemented in 1999 with the aim of stimulating competition in the market, improve the quality of drugs and improve the access of the population to drug treatment. The process of implementing this policy allowed the introduction and discussion of concepts that had never before been used in the context of drug registration in Brazil: bioavailability, bioequivalence, pharmaceutical equivalence, generic drugs, biopharmaceutical classification system, biowaiver. The present article provides definitions for these concepts in the context of Brazilian legislation as well as a historical and chronological description of the implementation of the generic drugs policy in Brazil, including a list of current generic drug legislation. This article contributes to the understanding of the Brazilian generic drugs policy and facilitates the search for information concerning the legal requirements for registration of drugs in Brazil.

[Generic drugs in Brazil: historical overview and legislation]. / Medicamentos genéricos no Brasil: panorama histórico e legislação.

The Brazilian generic drugs policy was implemented in 1999 with the aim of stimulating competition in the market, improve the quality of drugs and improve the access of the population to drug treatment. The process of implementing this policy allowed the introduction and discussion of concepts that had never before been used in the context of drug registration in Brazil: bioavailability, bioequivalence, pharmaceutical equivalence, generic drugs, biopharmaceutical classification system, biowaiver. The present article provides definitions for these concepts in the context of Brazilian legislation as well as a historical and chronological description of the implementation of the generic drugs policy in Brazil, including a list of current generic drug legislation. This article contributes to the understanding of the Brazilian generic drugs policy and facilitates the search for information concerning the legal requirements for registration of drugs in Brazil.