Leishmaniasis is a neglected and endemic disease that affects poorest population mainly in developing countries. A lack of adequate and definitive chemotherapeutic agents to fight against this infection has led to the investigation of numerous compounds. The aim of this study was to investigate in vitro activity of boldine against Leishmania amazonensis murine cell infection. Boldine ((S)-2,9-dihydroxy-1,10-dimethoxy-aporphine) is an aporphine alkaloid found abundantly in the leaves/bark of boldo (Peumus boldus Molina), a widely distributed tree native to Chile. The in vitro system consisted of murine macrophage infection with amastigotes of L. amazonensis treated with different concentrations from 50 to 600 μg/ml of boldine for 24 hr. Intracellular parasite destruction was assessed by morphological examination and boldine cytotoxicity to macrophages was tested by the MTT viability assay. When cells were treated with 100 μg/ml of boldine the reduction of parasite infection was 81% compared with untreated cultures cells. Interestingly, boldine-treatment caused a concentration-dependent decrease of macrophage infection that culminated with 96% of reduction when cells were submitted to 600 μg/ml of boldine. Cell cultures exposed to 100 μg/ml of boldine and 300 μg/ml of Glucantime® during 24 hr showed a significant reduction of 50% in parasitized cells compared with cell cultures exposed just to Glucantime®. The study showed that treatment with boldine produces a better effect than treatment with the reference antimonial drug, glucantime, in L. amazonensis infected macrophage. Our results suggest that boldine is a potentially useful agent for the treatment of leishmaniasis.
Cell Culture Techniques ; Chile ; Developing Countries ; Endemic Diseases ; In Vitro Techniques ; Leishmania* ; Leishmaniasis ; Macrophages ; Neglected Diseases ; Parasites ; Peumus ; Trees

OBJECTIVEUse of cisplatin, a conventional anticancer drug, is restricted because it generates strong hepatotoxicity by accumulating in liver. Therefore its anticancer potential can only be fully exploited if its own toxicity is considerably reduced. Towards this goal, ethanolic extract of the plant, Boldo (Peumus boldus), known for its antihepatotoxic effects, was used simultaneously with cisplatin, to test its ability to reduce cisplatin's cytotoxicity without affecting its anticancer potential.

METHODSThe cytotoxicity of Boldo extract (BE) and cisplatin, administered alone and in combination, was determined in three cancer cell lines (A549, HeLa, and HepG2) and in normal liver cells (WRL-68). Drug-DNA interaction, DNA damage, cell cycle, apoptosis, reactive oxygen species (ROS) and mitochondrial membrane potential (MMP, ΔΨ) were also studied. Hepatotoxicity and antioxidant activity levels were determined by alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase and glutathione assays in mice. The cytotoxicity of related proteins was tested by Western blotting.

RESULTSCo-administration of BE and cisplatin increased viability of normal cells, but had no effect on the viability of cancer cells. Boldo protected liver from damage and normalized different antioxidant enzyme levels in vivo and also reduced ROS and re-polarized MMP in vitro. Bax and cytochrome c translocation was reduced with caspase 3 down-regulation. Further, a drug-DNA interaction study revealed that BE reduced cisplatin's DNA-binding capacity, resulting in a reduction in DNA damage.

CONCLUSIONResults indicated that a low dose of BE could be used beneficially in combination with cisplatin to reduce its toxicity without hampering cisplatin's anticancer effect. These findings signify a potential future use of BE in cancer therapy.

Animals ; Antineoplastic Agents ; toxicity ; Cells, Cultured ; Cisplatin ; toxicity ; DNA Damage ; Female ; Glutathione ; metabolism ; Hepatocytes ; drug effects ; metabolism ; pathology ; Humans ; Male ; Mice ; Neoplasms ; drug therapy ; pathology ; Peumus ; Plant Extracts ; pharmacology