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      Atovaquone, chloroquine, primaquine, quinine and tetracycline: antiproliferative effects of relevant antimalarials on Neospora caninum Translated title: Atovaquona, cloroquina, primaquina, quinino e tetraciclina: efeitos antiproliferativos de antimaláricos relevantes em Neospora caninum


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          Abstract Neospora caninum is an apicomplexan parasite that causes abortion in cattle, resulting in significant economic losses. There is no commercial treatment for neosporosis, and drug repositioning is a fast strategy to test possible candidates against N. caninum. In this article, we describe the effects of atovaquone, chloroquine, quinine, primaquine and tetracycline on N. caninum proliferation. The IC50 concentrations in N. caninum were compared to the current information based on previous studies for Plasmodium and Toxoplasma gondii, correlating to the described mechanisms of action of each tested drug. The inhibitory patterns indicate similarities and differences among N. caninum, Plasmodium and T. gondii. For example, atovaquone demonstrates high antiparasitic activity in all the analyzed models, while chloroquine does not inhibit N. caninum. On the other hand, tetracycline is effective against Plasmodium and N. caninum, despite its low activity in T. gondii models. The repurposing of antimalarial drugs in N. caninum is a fast and inexpensive way to develop novel formulations using well-established compounds.

          Translated abstract

          Resumo Neospora caninum é um parasita Apicomplexa relacionado a abortos no gado bovino, que resultam em impactos econômicos. Não há tratamento comercial para neosporosis e o reposicionamento de drogas indica uma estratégia rápida para testar candidatos anti-N. caninum. Neste artigo, são descritos os efeitos da atovaquona, cloroquina, quinino, primaquine e tetraciclina na proliferação de N. caninum. As concentrações IC50 em N. caninum foram comparadas com a informação disponível, baseada em estudos publicados previamente para Plasmodium e Toxoplasma gondii, incluindo a correlação com os mecanismos de ação descritos para cada droga testada. Os padrões de inibição indicam pontos de similaridades e diferenças entre N. caninum, Plasmodium e T. gondii. Por exemplo, a atovaquona demonstra uma alta atividade antiparasitária em todos os modelos testados, enquanto a cloroquina não inibe N. caninum. Por outro lado, a tetraciclina é efetiva contra Plasmodium e N. caninum, em contraste com a baixa atividade em modelos de T. gondii. O reposicionamento de drogas antimaláricas em N. caninum é uma forma rápida e de baixo custo para o desenvolvimento de novas formulações que usam compostos bem estabelecidos.

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          Most cited references82

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                Author and article information

                Revista Brasileira de Parasitologia Veterinária
                Rev. Bras. Parasitol. Vet.
                Colégio Brasileiro de Parasitologia Veterinária (Jaboticabal, SP, Brazil )
                : 30
                : 1
                : e022120
                [01] Ribeirão Preto orgnameUniversidade de São Paulo orgdiv1Faculdade de Ciências Farmacêuticas de Ribeirão Preto orgdiv2Toxicológicas e Bromatológicas Brazil
                S1984-29612021000100312 S1984-2961(21)03000100312

                This work is licensed under a Creative Commons Attribution 4.0 International License.

                : 20 January 2021
                : 09 October 2020
                Page count
                Figures: 0, Tables: 0, Equations: 0, References: 82, Pages: 0

                SciELO Brazil

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                Original Article

                tetraciclina,primaquine,quinino,cloroquina,atovaquona,Neospora caninum,tetracycline,quinine,chloroquine,atovaquone


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