Acyclic Sesquiterpenes from the Fruit Pericarp of Sapindus saponaria Induce Ultrastructural Alterations and Cell Death in Leishmania amazonensis

Received Mar 5, 2017; Revised Jun 29, 2017; Accepted Jul 19, 2017

This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

1. Introduction

Sapindus saponaria L. (Sapindaceae) is a tropical tree species that is regularly found within the north, northeast, and central west areas of Brazil. Its height ranges from 4 to 9 m, and it presents bright brown-colored fruits 2 cm in diameter [1].

S. saponaria L., easily accessible owing to its popularity, has diverse traditional uses in the treatment of diseases of the nervous, respiratory, and genitourinary systems, in addition to being used to heal skin illnesses and as a biocide. The fruits, bark, and root of this species are employed in folk medicine as an astringent, soothing, expectorant, diuretic, tonic, and antitussive agent [2]. Potential activities of Sapindus species, including antimicrobial, antidiabetic, molluscicidal, cytotoxic, fungicidal, and anti-inflammatory, are attributed to the presence of, among other substances, glycosides [3].

Fruits of S. saponaria L. possess various glycosides in their pericarps. There are 30 saponins derived from the hederagenin triterpene oleanolic acid and 63 acyclic sesquiterpene oligoglycosides, as shown by liquid chromatography with UV-detection and MS (LC/UV/ESI-MS) and MS/MS fragmentation studies [4].

Glycosides are also considered promising antiprotozoal agents, particularly against Leishmania spp. [5–9]. The protozoa that cause leishmaniasis are transmitted by sandflies (insects of Lutzomyia spp. and Phlebotomus spp.) that are intermediate hosts of flagellated promastigote forms of the parasite [10, 11].

An understudied disease, leishmaniasis, is prevalent in America, Africa, and Asia, mainly in developing countries, but also in Europe [12]. Despite its prevalence, few drugs have been applied to treat this illness, and high toxicity and pronounced side effects have...