Laboratory for Research in Microbiology, Department of Parasitology and Microbiology, Federal University of Piauí, Teresina, PI, Brazil.
Medicinal Plants Research Center, Federal University of Piauí, Teresina, PI, Brazil.
Chem Biol Interact. 2021 Feb 25;336:109389. doi: 10.1016/j.cbi.2021.109389. Epub 2021 Jan 21.
Leishmaniases are infectious diseases caused by protozoa of the genus Leishmania, that may have different clinical manifestations. First line drugs used in the treatment of leishmaniosis are high costly, and are very aggressive requiring medical monitoring. Thus new therapeutic alternatives are needed and, in this context, natural products have been considered as a source of new antileishmania agents. Riparins are alkamides found in the unripe fruits of Aniba riparia. Several biological activities are described for this group of compounds, such as antimicrobial and antiparasitic potential. The objective of this work was to evaluate the anti-leishmania activity riparin E (Rip-E) in vitro, against promastigotes and internalized amastigotes of Leishmania amazonensis. Rip-E was able to inhibit promastigote cell growth (IC 4.7 μg/ml) and to reduce the percentage of macrophages infected with amastigotes, reducing its infectivity (survival index) (IC 1.3 μg/ml). The cytotoxicity against BALB/c murine macrophages was also assessed (CC 50.6 μg/ml) and the selectivity index was 38.9. Rip-E also demonstrated immunomodulatory activity, evidenced by the increase of the phagocytic capacity and lysosomal activity. However, Rip-E did not affect directly the production of nitric oxide. These results suggest that Rip-E has antileishmania potential, by both its direct inhibitory effect and its ability to activate macrophages.
利什曼病是由利什曼原虫属原生动物引起的传染病，可能具有不同的临床表现。治疗利什曼病的一线药物费用高昂，且非常具有侵袭性，需要医疗监测。因此，需要新的治疗选择，在这种情况下，天然产物被认为是新的抗利什曼原虫药物的来源。里帕林是在未成熟的 Aniba riparia 果实中发现的一种酰胺。该化合物组具有多种生物学活性，如抗菌和抗寄生虫潜力。这项工作的目的是评估 Riparin E（Rip-E）在体外对 promastigotes 和 Leishmania amazonensis 内化的 amastigotes 的抗利什曼原虫活性。Rip-E 能够抑制 promastigote 细胞生长（IC 4.7μg/ml），并降低被 amastigote 感染的巨噬细胞的百分比，从而降低其感染性（生存指数）（IC 1.3μg/ml）。还评估了 Rip-E 对 BALB/c 小鼠巨噬细胞的细胞毒性（CC 50.6μg/ml），其选择性指数为 38.9。Rip-E 还表现出免疫调节活性，这表现为吞噬能力和溶酶体活性的增加。然而，Rip-E 并没有直接影响一氧化氮的产生。这些结果表明，Rip-E 具有抗利什曼原虫的潜力，这既是由于其直接抑制作用，也是由于其激活巨噬细胞的能力。
