Poloxamer 407 (Pluronic(®) F127)-based polymeric micelles for amphotericin B: In vitro biological activity, toxicity and in vivo therapeutic efficacy against murine tegumentary leishmaniasis.

In the present study, a Poloxamer 407-based amphotericin B (AmpB)-containing polymeric micelles system (AmpB/M) was employed in the treatment of Leishmania amazonensis-infected BALB/c mice. Initially, the in vitro antileishmanial activity (IC50 value) of AmpB/M and B-AmpB/M (empty micelles) against stationary promastigotes and amastigotes-like forms of the parasites was determined, and results were of 1.83 ± 0.4 and 22.1 ± 0.7 μM, respectively, for the promastigotes, and of 2.27 ± 0.5 and 33.98 ± 2.6 μM, respectively, for the amastigotes-like. The cytotoxic concentration (CC50) values of these products were also evaluated, and we found the results of 119.5 ± 9.6 and 134.7 ± 10.3 μM, respectively. With these values, the selectivity index (SI) was calculated and results were of 65.3 and 5.4, respectively, for the promastigotes, and of 59.3 and 3.96, respectively, for the amastigotes-like of the parasites. Free AmpB showed IC50 values of 1.2 ± 0.3 and 2.5 ± 0.5 μM for the promastigotes and amastigotes-like, respectively, whereas the CC50 value was of 9.5 ± 0.4 μM. The SI values of this drug were of 7.9 and 3.8, respectively, for the promastigote and amastigote-like stages of the parasites. After, animals were infected and received saline or were treated subcutaneously with free AmpB, AmpB/M or B-AmpB/M. In the results, free AmpB-treated and infected mice showed reductions in their body weight, which were associated with hepatic and renal damage; however, no organic alteration was observed in the AmpB/M-treated animals. In addition, these animals showed significant reductions in their lesion average size and in the parasite burden in all evaluated infected tissue and organs, when compared to the other groups; as well as significantly higher levels of antileishmanial IFN-γ, IL-12, GM-CSF and nitrite, which were associated with low production of IL-4, IL-10 and IgG1 isotype antibodies. In conclusion, this AmpB/M system could be considered as an alternative for future studies in the treatment of tegumentary leishmaniasis.

Mendonça DV ，Lage LM ，Lage DP ，Chávez-Fumagalli MA ，Ludolf F ，Roatt BM ，Menezes-Souza D ，Faraco AA ，Castilho RO ，Tavares CA ，Barichello JM ，Duarte MC ，Coelho EA ... -  《-》

A Pluronic® F127-based polymeric micelle system containing an antileishmanial molecule is immunotherapeutic and effective in the treatment against Leishmania amazonensis infection.

Clioquinol (5-chloro-7-iodoquinolin-8-ol or ICHQ) was recently showed to presents an in vitro effective antileishmanial action, causing changes in membrane permeability, mitochondrial functionality, and parasite morphology. In the present study, ICHQ was incorporated into a Poloxamer 407-based polymeric micelles system (ICHQ/M), and its antileishmanial activity was in vivo evaluated in L. amazonensis-infected BALB/c mice. Amphotericin B (AmpB) and its liposomal formulation (Ambisome®) were used as controls. Parasitological and immunological evaluations were performed 30 days after the treatment. Results indicated more significant reductions in the average lesion diameter and parasite burden in ICHQ or ICHQ/M-treated mice, which were associated with the development of a polarized Th1 immune response, based on production of high levels of IFN-γ, IL-12, TNF-α, GM-CSF, and antileishmanial IgG2a antibody. Control groups´ mice produced high levels of IL-4, IL-10, and IgG1 isotype antibody. No organic toxicity was found by using ICHQ or ICHQ/M to treat the animals, although those receiving AmpB and Ambisome® have presented higher levels of renal and hepatic damage markers. In conclusion, results suggested that the ICHQ/M composition can be considered as an antileishmanial candidate to be tested against human leishmaniasis.

Tavares GSV ，Mendonça DVC ，Miyazaki CK ，Lage DP ，Soyer TG ，Carvalho LM ，Ottoni FM ，Dias DS ，Ribeiro PAF ，Antinarelli LMR ，Ludolf F ，Duarte MC ，Coimbra ES ，Chávez-Fumagalli MA ，Roatt BM ，Menezes-Souza D ，Barichello JM ，Alves RJ ，Coelho EAF ... -  《-》

Evaluation of the in vitro and in vivo antileishmanial activity of a chloroquinolin derivative against Leishmania species capable of causing tegumentary and visceral leishmaniasis.

The treatment against leishmaniasis presents problems, since the currently used drugs are toxic and/or have high costs. In addition, parasite resistance has increased. As a consequence, in this study, a chloroquinolin derivative, namely 7-chloro-N,N-dimethylquinolin-4-amine or GF1059, was in vitro and in vivo tested against Leishmania parasites. Experiments were performed to evaluate in vitro antileishmanial activity and cytotoxicity, as well as the treatment of infected macrophages and the inhibition of infection using pre-treated parasites. This study also investigated the GF1059 mechanism of action in L. amazonensis. Results showed that the compound was highly effective against L. infantum and L. amazonensis, presenting a selectivity index of 154.6 and 86.4, respectively, against promastigotes and of 137.6 and 74.3, respectively, against amastigotes. GF1059 was also effective in the treatment of infected macrophages and inhibited the infection of these cells when parasites were pre-incubated with it. The molecule also induced changes in the parasites' mitochondrial membrane potential and cell integrity, and caused an increase in the reactive oxygen species production in L. amazonensis. Experiments performed in BALB/c mice, which had been previously infected with L. amazonensis promastigotes, and thus treated with GF1059, showed that these animals presented significant reductions in the parasite load when the infected tissue, spleen, liver, and draining lymph node were evaluated. GF1059-treated mice presented both lower parasitism and low levels of enzymatic markers, as compared to those receiving amphotericin B, which was used as control. In conclusion, data suggested that GF1059 can be considered a possible therapeutic target to be tested against leishmaniasis.

Soyer TG ，Mendonça DVC ，Tavares GSV ，Lage DP ，Dias DS ，Ribeiro PAF ，Perin L ，Ludolf F ，Coelho VTS ，Ferreira ACG ，Neves PHAS ，Matos GF ，Chávez-Fumagalli MA ，Coimbra ES ，Pereira GR ，Coelho EAF ，Antinarelli LMR ... -  《-》

An 8-hydroxyquinoline-containing polymeric micelle system is effective for the treatment of murine tegumentary leishmaniasis.

Lage LM ，Barichello JM ，Lage DP ，Mendonça DV ，Carvalho AM ，Rodrigues MR ，Menezes-Souza D ，Roatt BM ，Alves RJ ，Tavares CA ，Coelho EA ，Duarte MC ... -  《-》

In vitro and in vivo antileishmanial activity of a fluoroquinoline derivate against Leishmania infantum and Leishmania amazonensis species.

New therapeutics against leishmaniasis are desirable, since the current drugs applied against this disease complex presents problems, such as the toxicity, high cost and/or parasite resistance. In the present study, a new fluoroquinoline derivate, namely 7-chloro-N-(4-fluorophenethyl)quinolin-4-amine or GF1061, was evaluated regarding to its in vitro antileishmanial action against Leishmania infantum and L. amazonensis species, as well as by its toxicity in mammalian cells and efficacy in the treatment of infected macrophages. The mechanism of action of this molecule in L. amazonensis and the therapeutic efficacy in infected BALB/c mice were also evaluated. Results showed that GF1061 was effective against both parasite species, showing selectivity index (SI) of 38.7 and 42.7 against L. infantum and L. amazonensis promastigotes, respectively, and of 45.0 and 48.9 against the amastigotes, respectively. Amphotericin B (AmpB), used as control, showed SI values of 6.6 and 8.8 against L. infantum and L. amazonensis promastigotes, respectively, and of 2.2 and 2.7 against the amastigotes, respectively. The molecule was effective in treat infected macrophages, as well as it induced alterations in the mitochondrial membrane potential, increase in the reactive oxygen species production, and in the cell integrity of the parasites. Regarding to the in vivo experiments, BALB/c mice (n = 8 per group) were subcutaneously infected with 106L. amazonensis stationary promastigotes and, 60 days post-infection, they received saline or were treated during 10 days, once a day, with AmpB (1 mg/kg body weight) or GF1061 (5 mg/kg body weight). One day after the treatment, the infected tissue, spleen, liver, and draining lymph node (dLN) of the animals were collected, and the parasite load was evaluated. GF1061-treated mice, as compared to the saline and AmpB groups, showed significant reductions in the parasitism in the infected tissue (66% and 62%, respectively), liver (69% and 44%, respectively), spleen (71% and 38%, respectively), and dLN (72% and 48%, respectively). In conclusion, results suggested that GF1061 may be considered as a possible therapeutic target to be evaluated against leishmaniasis in other mammalian hosts.

Tavares GSV ，Mendonça DVC ，Lage DP ，Antinarelli LMR ，Soyer TG ，Senna AJS ，Matos GF ，Dias DS ，Ribeiro PAF ，Batista JPT ，Poletto JM ，Brandão GC ，Chávez-Fumagalli MA ，Pereira GR ，Coimbra ES ，Coelho EAF ... -  《-》