DETC Induces Leishmania Parasite Killing in Human In Vitro and Murine In Vivo Models: A Promising Therapeutic Alternative in Leishmaniasis

Abstract

BackgroundChemotherapy remains the primary tool for treatment and control of human leishmaniasis. However, currently available drugs present serious problems regarding side-effects, variable efficacy, and cost. Affordable and less toxic drugs are urgently needed for leishmaniasis.Methodology/Principal FindingsWe demonstrate, by microscopy and viability assays, that superoxide dismutase inhibitor diethyldithiocarbamate (DETC) dose-dependently induces parasite killing (p<0.001) and is able to “sterilize” Leishmania amazonensis infection at 2 mM in human macrophages in vitro. We also show that DETC-induced superoxide production (p<0.001) and parasite destruction (p<0.05) were reverted by the addition of the antioxidant N-acetylcysteine, indicating that DETC-induced killing occurs through oxidative damage. Furthermore, ultrastructural analysis by electron microscopy demonstrates a rapid and highly selective destruction of amastigotes in the phagosome upon DETC treatment, without any apparent damage to the host cell, including its mitochondria. In addition, DETC significantly induced parasite killing in Leishmania promastigotes in axenic culture. In murine macrophages infected with Leishmania braziliensis, DETC significantly induced in vitro superoxide production (p = 0.0049) and parasite killing (p = 0.0043). In vivo treatment with DETC in BALB/C mice infected with Leishmania braziliensis caused a significant decrease in lesion size (p<0.0001), paralleled by a 100-fold decrease (p = 0.0087) in parasite burden.Conclusions/SignificanceDue to its strong leishmanicidal effect in human macrophages in vitro, its in vivo effectiveness in a murine model, and its previously demonstrated in vivo safety profile in HIV treatment, DETC treatment might be considered as a valuable therapeutic option in human leishmaniasis, including HIV/Leishmania co-infection.

The Effect of (-)-Epigallocatechin 3-O - Gallate In Vitro and In Vivo in Leishmania braziliensis: Involvement of Reactive Oxygen Species as a Mechanism of Action

“…The exposure of L. amazonensis -infected macrophages to diethyldithiocarbamate (DETC) [28] and quercetin [34] has been shown to increase superoxide anion and reactive oxygen species levels, respectively. These effects subsequently induce a severe reduction in the number of intracellular parasites and demonstrate the efficacy of ROS as an antimicrobial agent against intracellular parasites.…”

“…The method of treatment was similar to previously described methods [27], [28] and initiated 21 days following infection. EGCG (100 mg/kg/day) was diluted in PBS and administered orally once daily seven times a week until the end of the experiment (day 32) when the animals were euthanized.…”

DETC-based bacterial cellulose bio-curatives for topical treatment of cutaneous leishmaniasis

“…Pharmacological inhibition of CuZnSOD/SOD1 with Diethyldithiocarbamate (DETC), a copper chelator that targets SOD110, significantly reduced Leishmania infection in vitro 8 as a result of increased superoxide levels. In vivo , intraperitoneal injection of DETC inhibited CL development in L. braziliensis- infected mice11, indicating the feasibility of treating CL by targeting SOD1-associated pathways.…”

Estudo do efeito leishmanicida da dermaseptina-01, um peptídeo antimicrobiano de Phyllomedusa azurea

“…Para determinar a eficácia do tratamento com o peptídeo, os macrófagos peritoneais infectados com 10 6 formas amastigotas de L. amazonensis, incubados por 2 horas, em placa de 24 escavações, com as diferentes concentrações de DRS-01 (1, 4 ou 16 µg/mL), e lavados com STF, pH 7,2 conforme descrito no item 3.5, foram novamente incubados em meio Schneider (Sigma), pH 6,7, suplementado com 40 μg/mL de gentamicina e 20% de soro fetal bovino estéril, a 26 ºC, durante 5 dias, segundo o método descrito por Khouri et al (2010) e modificado por Alves et al (2014). Este meio é adequado para a sobrevivência das leishmânias, mas o pH baixo e a temperatura são incompatíveis com a sobrevivência dos macrófagos.…”

“…Sabe-se que a morte de parasitos como L. braziliensis e L.amazonensis é dependente de O2 - (Khouri et al 2010) que é um precursor das espécies reativas de oxigênio como o peróxido de hidrogênio (H2O2), o radical hidroxila (HO) e Hipoclorito (HOCl).…”