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Ars pharm ; 62(1): 89-95, ene.-mar. 2021.
Artigo em Inglês | IBECS | ID: ibc-ET6-1764


INTRODUCTION: The coronavirus disease 2019 (COVID-19) is a viral disease that affects several human organs and sys¬tems. Preventive or prophylactic treatments are specifically useful in emerging infectious diseases such as COVID-19 because they reduce the need for hospitalization and public health spending. Although the SARS-CoV-2 preventive effect of several therapeutic agents (e.g., hydroxychloroquine/chloroquine, remdesivir, lopinavir, and ritonavir) has been extensively evaluated, none of them have demonstrated significant clinical efficacy. METHOD: We aim to address and discuss the recently published studies on the chemoprophylactic potential of quer¬cetin against SARS-CoV-2. A literature search was carried out on different databases, such as PubMed/MEDLINE, Scielo, Scopus, Web of Science, Cochrane Library, and Clinical Studies that report the effect of quercetin against SARS-CoV-2 or other types of coronaviruses were included and critically evaluated. RESULTS: Studies have shown that quercetin, an FDA-approved flavonoid used as an antioxidant and anti-inflamma¬tory agent, inhibits the entry of coronavirus (SARS-CoV) into the host cell. Moreover, an in silico study showed that quercetin is a potent inhibitor of the SARS-CoV-2 main protease (Mpro), suggesting that this flavonoid is also active against COVID-19. CONCLUSIONS: Because quercetin might prevent and lessen the duration of SARS-CoV-2 infections, it is plausible to assume that the prophylactic use of this flavonoid produces several clinical benefits. However, this preliminary evidence needs to be confirmed by in vitro assays and, posteriorly, in randomized clinical trials

INTRODUCCIÓN: La enfermedad del coronavirus 2019 (COVID-19) es una enfermedad viral que afecta a varios órganosy sistemas. Los tratamientos preventivos o profilácticos son especialmente útiles en enfermedades infecciosas emergentes como COVID-19 porque reducen la necesidad de hospitalización y el gasto en salud pública. Aunque el efecto preventivo del SARS-CoV-2 de varios agentes terapéuticos (e.g., hidroxicloroquina/cloroquina, remdesivir,lopinavir y ritonavir) se ha evaluado ampliamente, ninguno de ellos ha demostrado una gran eficacia clínica. MÉTODO: Por lo tanto, aquí nuestro objetivo es abordar y discutir los estudios publicados recientemente sobre el potencial quimioprofilático de la quercetina contra el SARS-CoV-2. METODOLOGÍA: Se realizó una búsqueda de la literaturaen bases como PubMed/MEDLINE, Scielo, Scorpus, Web of Science, Cochrane Library y Clinical Se incluyeron y evaluaron críticamente estudios que abordan la quercetina contra el SARS-CoV-2 u otros tipos decoronavirus. RESULTADOS: Algunos estudios han demostrado que la quercetina, un flavonoide aprobado por la FDA que se utiliza como agente antioxidante y antiinflamatorio, inhibe la entrada del coronavirus (SARS-CoV) en la célula huésped.Además, un estudio in silico mostró que la quercetina es un potente inhibidor de la proteasa principal del SARSCoV-2 (Mpro), lo que sugiere que este flavonoide también es activo contra COVID-19. CONCLUSIONES: Debido a que la quercetina podría prevenir y disminuir la duración de las infecciones por SARSCoV-2, es plausible suponer que el uso profiláctico de este flavonoide produce varios beneficios clínicos. Pero, estas pruebas preliminares deben ser confirmadas mediante ensayos in vitro y, posteriormente, en un ensayo clínico aleatorizado

Humanos , Quercetina/uso terapêutico , Profilaxia Pré-Exposição/métodos , Infecções por Coronavirus/prevenção & controle , Antivirais/uso terapêutico , Suplementos Nutricionais , Inibidores de Proteases/uso terapêutico , Reprodutibilidade dos Testes
J Ethnopharmacol ; 266: 113423, 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33007390


ETHNOPHARMACOLOGICAL RELEVANCE: Pristimerin is a triterpenoid considered the main component of Salacia crassifolia extracts. This terpene has shown promising antitumor, anti-inflammatory, and antimicrobial effects. Likewise, S. crassifolia has been used in traditional medicine to treat cancer and as an antimicrobial and anti-inflammatory agent. AIM OF THE STUDY: This study aimed to evaluate the antibacterial activity of the hexane extract of Salacia crassifolia roots (HER) and its isolate, pristimerin, against pathogenic bacteria. MATERIALS AND METHODS: First, we evaluated the spectrum of action of HER and pristimerin by the determination of the minimum inhibitory concentration (MIC) and the minimal bactericidal concentration (MBC). Subsequently, we analyzed the time-kill curve of these plant-derived compounds against Staphylococcus aureus. Then, we examined their mode of action by three different assays: the crystal violet methodology, the release of intracellular material, and transmission electron microscopy methods (TEM). Finally, we evaluated the effect of HER and pristimerin on the pre-formed biofilm of S. aureus by the crystal violet assay, the synergistic effect by the checkerboard method, the cytotoxicity against Vero cells, and the in silico activity using the online software PASS. RESULTS: HER and pristimerin presented a narrow spectrum of action against Gram-positive bacteria (MIC 0.195-25 µg/mL), and their primary mode of action is the alteration of membrane permeability of S. aureus. Our results show that the compounds disrupted the pre-formed biofilm of S. aureus in a dose-dependent manner. Furthermore, HER and pristimerin presented a significant synergic effect after the combination with well-known antibiotics, which was associated with the ability of these phytomedicines to change membrane permeability. Regarding the cytotoxic effect, the selective index (SI) of HER ranged from 0.37 to 11.86, and the SI of pristimerin varied from 0.24 to 30.87, according to the bacteria tested. CONCLUSIONS: Overall, HER and pristimerin showed a promising antibacterial effect in vitro through the alteration of membrane permeability of S. aureus.

Arch Virol ; 165(8): 1729-1737, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32514689


The novel human coronavirus (SARS-CoV-2), the causative agent of COVID-19, has quickly become a threat to the public health and economy worldwide. Despite the severity of some cases, there are no current pathogen-specific antivirals available to treat the disease. Therefore, many studies have focused on the evaluation of the anti-SARS-CoV-2 activity of clinically available drugs. Here, we conducted a systematic review to describe the drug repositioning strategy against SARS-CoV-2 and to discuss the clinical impact of this approach in the current pandemic context. The systematic review was performed on March 23, 2020, using PubMed/MEDLINE, Scopus, Cochrane Library, and Biblioteca Virtual de Saúde (BVS). The data were summarized in tables and critically analyzed. After the database search, 12 relevant studies were identified as eligible for the review. Among the drugs reported in these studies, 57 showed some evidence of antiviral activity. Antivirals, especially antiretrovirals, are the main class of therapeutic agents evaluated against COVID-19. Moreover, studies have reported the anti-SARS-CoV-2 activity of antitumor (16%; 9/57), antimalarial (7%, 4/57), and antibacterial (5%; 3/57) agents. Additionally, seven pharmacological agents (chloroquine, tetrandrine, umifenovir (arbidol), carrimycin, damageprevir, lopinavir/ritonavir) are in phase IV of clinical trials. Due to the evidence of the anti-SARS-CoV-2 activity of various clinically available agents, drug repositioning stands out as a promising strategy for a short-term response in the fight against the novel coronavirus.

Antibacterianos/farmacologia , Antirretrovirais/farmacologia , Antimaláricos/farmacologia , Antineoplásicos/farmacologia , Betacoronavirus/efeitos dos fármacos , Infecções por Coronavirus/tratamento farmacológico , Reposicionamento de Medicamentos , Pneumonia Viral/tratamento farmacológico , Antivirais/farmacologia , Infecções por Coronavirus/prevenção & controle , Humanos , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle
Antiviral Res ; 168: 76-81, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31125633


Mayaro virus (MAYV) is a sublethal arbovirus transmitted by mosquitoes with possible installation of an urban cycle in the Americas. Its infection causes disabling arthralgia, and still, there is no vaccine or treatment to it. We recently investigated nearly 600 compounds by molecular docking and identified epicatechin as a potent antiviral against MAYV. The root extract of Maytenus imbricata showed anti-MAYV activity and two isolated compounds from this plant were also evaluated in vitro. Proanthocyanidin (PAC), a dimer containing epicatechin, showed an effective concentration for 50% of the cells infected by MAYV (EC50) of 37.9 ±â€¯2.4 µM and a selectivity index (SI) above 40. PAC showed significant virucidal activity, inhibiting 100% of the virus proliferation (7 log units), and caused moderate effect during adsorption and virus internalization stage. However, PAC was unable to block the infection when only the cells were pretreated. It was observed a reduction in virus yields when adding PAC at different moments after infection. The set of results indicates that PAC binds to viral and non-cellular elements and may inactivate the MAYV. The inactivation occurs before infection or when the virus reaches the extracellular environment from the 2nd cycle of infection that could block its progression cell-to-cell or to tissues not yet infected.

Alphavirus/efeitos dos fármacos , Antivirais/farmacologia , Proantocianidinas/farmacologia , Infecções por Alphavirus/virologia , Animais , Antivirais/química , Catequina/química , Catequina/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Magnoliopsida/química , Estrutura Molecular , Raízes de Plantas/química , Proantocianidinas/química , Células Vero , Ligação Viral/efeitos dos fármacos , Internalização do Vírus/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos