Astronium fraxinifolium Schott Exerts Leishmanicidal Activity by Providing a Classically Polarized Profile in Infected Macrophages

• Published in: Acta parasitologica 2020-09, Vol.65 (3), p.686-695
• Main Authors: Braga, Milena Aguiar, de Oliveira Rodrigues, Raphael, Yaochite, Juliana Navarro Ueda, Sasahara, Greyce Luri, Santos, Flávia Almeida, Fonseca, Francisco Rafael Marciano, de Castro Rodrigues, Naya Lucia, Teixeira, Maria Jânia, Junior, João Tavares Calixto, Rodrigues, Ana Livya Moreira, de Morais, Selene Maia, Nagao-Dias, Aparecida Tiemi
• Format: Article
• Language: English
• Subjects: Animal Systematics/Taxonomy/Biogeography; Baculovirus; Biomedical and Life Sciences; Biomedicine; Cell death; Cyclooxygenase-2; Drug discovery; Ecology; Evaluation; Fluorescence; Gene expression; Immune response; Immune response (cell-mediated); Immune system; Immunosuppressive agents; Inflammation; Interleukin 10; Interleukin 12; Interleukin 4; LAMP-1 protein; Macrophages; Medical Microbiology; Microbiology; Morbidity; Mucocutaneous leishmaniasis; Nitric-oxide synthase; Original Paper; Parasite resistance; Parasitology; Plant cells; Plant extracts; Polymerase chain reaction; Proteins; Superoxide anions; Toxicity; Tumor necrosis factor-α; Vacuoles; Vector-borne diseases
• ISSN: 1230-2821; 1896-1851
• DOI: 10.2478/s11686-020-00200-7

Background Leishmania braziliensis is prevalent in Latin American countries, including Brazil. It causes cutaneous and mucocutaneous leishmaniasis, leading to high morbidity, and has a low cure rate. Treatment is based on pentavalent antimonials; nonetheless, there are problems related to high toxicity, high cost, and parasitic resistance. Discovery of new leishmanicidal drugs without these limitations and that stimulate the cellular immune response is necessary. Purpose The present work evaluates whether Astronium fraxinifolium Schott exerts leishmanicidal activity against L. braziliensis by providing a classically polarized profile in infected macrophages. Methods For the evaluation of the A. fraxinifolium Schott leishmanicidal activity, amastigote cell death was demonstrated in infected RAW 267.4 macrophages treated with an ethanolic extract from the plant sapwood (EEAF). For the evaluation of the EEAF capacity in providing a classically polarized profile in infected macrophages, the following analyses were done: detection of LAMP-1 protein by the baculovirus technology, measurement of superoxide anion by the NBT testing, quantification of TNF-α, IL-12p40, IL-10, IL-4, and TGF-β by sandwich-type enzyme immune assays, and iNOS and COX-2 expression by RT-PCR technique. Results The EEAF significantly reduced amastigote counts inside the cells. Vacuoles were visualized in infected and treated cells before and after May–Grünwald–Giemsa staining . A strong LAMP-1 protein fluorescence revealed phagosome maturation in infected cells treated with the EEAF. No production of superoxide was visualized in infected cells treated with the plant material. Nonetheless, high levels of TNF-α, IL-12p40, and IL-10 were found in cell supernatants, but reduced levels of TGF-β and no IL-4 production. We identified augmented mRNA expression for COX-2, but no expression of iNOS mRNA. Conclusion Our results demonstrated that A. fraxinifolium induced a classically polarized profile in infected macrophages but also provided a less harmful environment by stimulating the production of certain anti-inflammatory mediators, such as IL-10.