Green SPIONs as a novel highly selective treatment for leishmaniasis: an in vitro study against Leishmania amazonensis intracellular amastigotes

The main goal of this work was to evaluate the therapeutic potential of green superparamagnetic iron oxide nanoparticles (SPIONs) produced with coconut water for treating cutaneous leishmaniasis caused by Leishmania amazonensis. Optical and electron microscopy techniques were used to evaluate the effects on cell proliferation, infectivity percentage, and ultrastructure. SPIONs were internalized by both parasite stages, randomly distributed in the cytosol and located mainly in membrane-bound compartments. The selectivity index for intracellular amastigotes was more than 240 times higher compared to current drugs used to treat the disease. The synthesized SPIONs showed promising activity against Leishmania and can be considered a strong candidate for a new therapeutic approach for treating leishmaniases

Co-protoporphyrin IX and Sn-protoporphyrin IX inactivate Zika, Chikungunya and other arboviruses by targeting the viral envelope

Universidade Federal do Rio de Janeiro. Instituto de Microbiologia Paulo de Goes, Centro de Ciências da Saúde. Rio de Janeiro, RJ, Brazil.Universidade Federal do Rio de Janeiro. Instituto de Microbiologia Paulo de Goes, Centro de Ciências da Saúde. Rio de Janeiro, RJ, Brazil.Universidade Federal do Rio de Janeiro. Instituto de Biologia. Rio de Janeiro, RJ, Brazil.Universidade Federal do Rio de Janeiro. Instituto de Microbiologia Paulo de Goes, Centro de Ciências da Saúde. Rio de Janeiro, RJ, Brazil.Universidade Federal do Rio de Janeiro. Instituto de Bioquímica Médica Leopoldo de Meis. Centro de Ciências da Saúde. Rio de Janeiro, RJ, Brazil / Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Ananindeua, PA, Brasil / Universidade do Estado do Pará. Departamento de Morfologia e Ciências Fisiológicas. Centro de Ciências Biológicas e da Saúde. Belém, PA, Brazil.Universidade Federal do Rio de Janeiro. Núcleo Multidisciplinar de Pesquisas. Polo Avançado de Xerém. Duque de Caxias, RJ, Brazil.Universidade Federal do Rio de Janeiro. Instituto de Microbiologia Paulo de Goes, Centro de Ciências da Saúde. Rio de Janeiro, RJ, Brazil.Universidade Federal do Rio de Janeiro. Núcleo Multidisciplinar de Pesquisas. Polo Avançado de Xerém. Duque de Caxias, RJ, Brazil.Universidade Federal do Rio de Janeiro. Instituto de Biologia. Rio de Janeiro, RJ, Brazil.Universidade Federal do Rio de Janeiro. Instituto de Bioquímica Médica Leopoldo de Meis. Centro de Ciências da Saúde. Rio de Janeiro, RJ, Brazil.Universidade Federal do Rio de Janeiro. Instituto de Microbiologia Paulo de Goes, Centro de Ciências da Saúde. Rio de Janeiro, RJ, Brazil.Universidade Federal do Rio de Janeiro. Instituto de Bioquímica Médica Leopoldo de Meis. Centro de Ciências da Saúde. Rio de Janeiro, RJ, BrazilUniversidade Federal do Rio de Janeiro. Instituto de Bioquímica Médica Leopoldo de Meis. Centro de Ciências da Saúde. Rio de Janeiro, RJ, BrazilUniversidade Federal do Rio de Janeiro. Instituto de Microbiologia Paulo de Goes, Centro de Ciências da Saúde. Rio de Janeiro, RJ, Brazil.The global situation of diseases transmitted by arthropod-borne viruses such as Dengue (DENV), Yellow Fever (YFV), Chikungunya (CHIKV) and Zika (ZIKV) viruses is alarming and treatment of human infection by these arboviruses faces several challenges. The discovery of broad-spectrum antiviral molecules, able to inactivate different groups of viruses, is an interesting approach. The viral envelope is a common structure among arboviruses, being a potential target for antivirals. Porphyrins are amphipathic molecules able to interact with membranes and absorb light, being widely used in photodynamic therapy. Previously, we showed that heme, Co-protoporphyrin IX (CoPPIX) and Sn-protoporphyrin IX (SnPPIX) directly inactivate DENV and YFV infectious particles. Here we demonstrate that the antiviral activity of these porphyrins can be broadened to CHIKV, ZIKV, Mayaro virus, Sindbis virus and Vesicular Stomatitis virus. Porphyrin treatment causes viral envelope protein loss, affecting viral morphology, adsorption and entry into target cells. Also, light-stimulation enhanced the SnPPIX activity against all tested arboviruses. In summary, CoPPIX and SnPPIX were shown to be efficient broad-spectrum compounds to inactivate medically and veterinary important viruses