The in vivo effect of natural compounds on Leishmania (L.) amazonensis.

GERMANÓ, MJ; CIFUENTES, D; TRONCOSO, M; GAMARRA-LUQUES, C; LOZANO, E; SOSA LOCHEDINO, AL; CARGNELUTTI, DE

Buenos Aires

Congreso; DRUG DISCOVERY FOR NEGLECTED DISEASES INTERNATIONAL CONGRESS 2018, 4h Scientific Meeting of the Research Network Natural Products against Neglected Diseases; 2018

Facultad de Farmacia y Bioquímica - Universidad de Buenos Aires Ciudad Autónoma de Buenos Aires, Argentina

The leishmaniases are a spectrum of diseases caused by infection with protozoan pathogens of the Leishmania genus,with an estimated 2 million new cases per annum [1]. Leishmania parasites are transmitted to a mammalian host via thebite of an infected sand fly. The clinical forms of the disease (cutaneous, mucocutaneous and visceral leishmaniasis)depend on the species of Leishmania involved. In Argentina, affects the northern region of the country with anincidence that has increased over the last two decades. Current treatments for leishmaniasis are unsatisfactory dueto high associated toxicity, cost, complex administration and the emergence of resistant strains. Efforts have greatlyincreased over the last decade to identify novel compounds with anti-leishmanial properties. Thus, one strategy inthe search for new compounds is the screening of molecules purified from plant sources. Terpenes appear as goodcandidates, because they are abundant in the plant kingdom and some of them have shown a significant activityagainst trypanosomatids. The diterpene 5-epi-icetexone (ICTX), isolated from Salvia gilliessi, is effective against T. cruziand Leishmania spp [2]. Moreover, there are more than five hundred species of plants in Mendoza province, central westArgentina for which ?folkloric medicine? has described several uses to preserve and aid health [3]. Tessaria absinthioides(Ts) and Prosopis strombulifera (Ps) have been used as an astringent, anti-inflammatory and anti-diarrheal agent [4, 5].Recent studies have confirmed its biological activities against different microorganisms [6-8]. The aqueous extracts (Aq)of both plants, TaAq and PsAq, have been shown to be not toxic in experimental animals [9, 10]. Objective: Evaluate theeffect of ICTX, PsAq and TaAq in an in vivo model of cutaneous leishmaniasis. Materials and methods: Male BALB/cmice were infected in the right footpad with 1x105 promastigotes of L (L.) amazonensis and localy treated (4 days), with1 mg/animal/day of ICTX. PsAq and TaAq were administrated oraly by diluting them in the drinking water. PsAq 150mg/animal/day and TaAq 300 mg/animal/day for 10 weeks. We analyze footpad swelling, parasite load and IgG levelsto determine the effectiveness of the treatments. Results and discussion: We observe that the treatment with thecompounds decreases footpad swelling compared to the controls. This is related to the significant decrease in parasiteload and IgG levels observed with every treatment. Although many more analyzes should be made, these naturalcompounds could be effective to treat cutaneous leishmaniasis.