Jenicer K. U. Yokoyama-Yasunaka

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OBJECTIVES The aim of this study was to evaluate the efficacy of tamoxifen in vivo in experimental models of cutaneous (CL) and visceral leishmaniasis (VL) caused by Leishmania braziliensis and Leishmania chagasi, respectively. METHODS Drug activity was assessed against intracellular amastigotes by treating infected macrophage cultures and evaluating the(More)
Given the lack of effective and safe alternatives to the drugs already in use, considerable efforts are being applied to the search of new therapeutic options to treat leishmaniasis. A necessary step in the discovery of antileishmanial drugs is the validation of drug candidates in mouse models. The standard methods to quantify the parasite burden in animal(More)
The synthesis and in vitro activity of R(+)-Limonene derivatives against Leishmania and Trypanosoma cruzi strains are reported. Seven compounds have shown better in vitro activity against Leishmania (V.)braziliensis than the standard drug pentamidine. Additionally, we have identified two promising new anti-T. cruzi limonene derivatives.
Limonene is a monoterpene that has antitumoral, antibiotic and antiprotozoal activity. In this study we demonstrate the activity of limonene against Leishmania species in vitro and in vivo. Limonene killed Leishmania amazonensis promastigotes and amastigotes with 50% inhibitory concentrations of 252.0+/-49.0 and 147.0+/-46.0 microM, respectively. Limonene(More)
OBJECTIVES This study was performed to investigate the activity of tamoxifen, an antioestrogen widely used in the treatment of breast cancer, against Leishmania. METHODS Drug activity was assessed in vitro against axenically grown promastigotes and amastigotes through cell counting or by measuring the cleavage of MTT, and against intracellular amastigotes(More)
BACKGROUND The treatment of leishmaniasis relies mostly on parenteral drugs with potentially serious adverse effects. Additionally, parasite resistance in the treatment of leishmaniasis has been demonstrated for the majority of drugs available, making the search for more effective and less toxic drugs and treatment regimens a priority for the control of(More)
Tamoxifen, an antineoplastic agent, is active in vitro and in vivo against the parasitic protozoa Leishmania. As part of our efforts to unravel this drug's mechanisms of action against the parasite and understand how resistance could arise, we tried to select tamoxifen-resistant Leishmania amazonensis. Three different strategies to generate tamoxifen(More)
Resistance of Leishmania parasites to specific chemotherapy has become a well-documented problem in the Indian subcontinent in recent years but only a few studies have focused on the susceptibility of American Leishmania isolates. Our susceptibility assays to meglumine antimoniate were performed against intracellular amastigotes after standardizing an in(More)
BACKGROUND Chemotherapy is still a critical issue in the management of leishmaniasis. Until recently, pentavalent antimonials, amphotericin B or pentamidine compounded the classical arsenal of treatment. All these drugs are toxic and have to be administered by the parenteral route. Tamoxifen has been used as an antiestrogen in the treatment and prevention(More)
Nitric oxide (NO) is considered a key molecule in the defense against intracellular pathogens, particularly Leishmania. The expression of inducible nitric oxide synthase and consequent production of NO by infected macrophages has been shown to correlate with leishmaniasis resistance in the murine model as well as in human patients. Nitric oxide donors have(More)