1
|
Tavares GDSV, Mendonça DVC, Lage DP, Granato JDT, Ottoni FM, Ludolf F, Chávez-Fumagalli MA, Duarte MC, Tavares CAP, Alves RJ, Coimbra ES, Coelho EAF. Antileishmanial Activity, Cytotoxicity and Mechanism of Action of Clioquinol Against Leishmania infantum and Leishmania amazonensis Species. Basic Clin Pharmacol Toxicol 2018; 123:236-246. [PMID: 29481714 DOI: 10.1111/bcpt.12990] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Accepted: 02/12/2018] [Indexed: 12/22/2022]
Abstract
In this study, a quinoline derivate, clioquinol (5-chloro-7-iodoquinolin-8-ol), was evaluated against Leishmania amazonensis and Leishmania infantum promastigotes and amastigotes. The cytotoxicity in murine macrophages and human red blood cells, as well as the efficacy in treating infected macrophages and the inhibition of infection using pre-treated parasites were also evaluated. Results showed that clioquinol inhibited L. amazonensis and L. infantum promastigotes with effective concentration 50% (EC50 ) values of 2.55 ± 0.25 and 1.44 ± 0.35 μg/mL, respectively, and of 1.88 ± 0.13 and 0.98 ± 0.17 μg/mL against axenic amastigotes, respectively. The cytotoxic EC50 concentrations of clioquinol in murine macrophages and human red blood cells were, respectively, 255 ± 23 and 489 ± 20 μg/mL. With these results, the selectivity index was calculated, showing values of 99.9 and 177.1 against promastigotes, respectively, and of 135.6 and 260.1 against axenic amastigotes, respectively. Significant reductions in the percentage of infected macrophages after treatment using clioquinol were also observed, as well as when parasites were pre-treated with clioquinol and used to infect murine macrophages. The mechanism of action of clioquinol was investigated in L. amazonensis, and results revealed morphological and biochemical alterations in the clioquinol-treated parasites, including reduction in cell volume, loss of mitochondrial membrane potential, increase in the ROS production and rupture of the plasma membrane. The externalization of phosphatidylserine (PS) at the cell surface was evaluated in treated parasites that had been doubly labelled with annexin and propidium iodide (PI). The results showed no significant difference for PS exposure when compared to the untreated control, although a significant increase in the PI/annexin V-labelled cell population was found in the treated parasites. Results suggest that clioquinol induces a discontinuity of the parasite membrane, possibly related to a characteristic event of cell death caused by necrosis. This study demonstrates, for the first time, the antileishmanial activity of clioquinol against two relevant Leishmania species and suggests that the mitochondria of the parasites may be a possible biological target leading to parasite necrosis. Our findings suggest that clioquinol may have a potential application in treatment of leishmaniasis and further studies should be performed in infected mammalian hosts.
Collapse
Affiliation(s)
- Grasiele de Sousa Vieira Tavares
- Post-graduate Program in Health Sciences: Infectious Diseases and Tropical Medicine, Medicine School, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Débora Vasconcelos Costa Mendonça
- Post-graduate Program in Health Sciences: Infectious Diseases and Tropical Medicine, Medicine School, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Daniela Pagliara Lage
- Post-graduate Program in Health Sciences: Infectious Diseases and Tropical Medicine, Medicine School, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Juliana da Trindade Granato
- Department of Parasitology, Microbiology and Immunology, Institute of Biological Sciences, Federal University of Juiz de Fora, Juiz de Fora, Minas Gerais, Brazil
| | - Flaviano Melo Ottoni
- Department of Pharmaceutical Products, Pharmacy School, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Fernanda Ludolf
- Post-graduate Program in Health Sciences: Infectious Diseases and Tropical Medicine, Medicine School, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Miguel Angel Chávez-Fumagalli
- Post-graduate Program in Health Sciences: Infectious Diseases and Tropical Medicine, Medicine School, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Mariana Costa Duarte
- Post-graduate Program in Health Sciences: Infectious Diseases and Tropical Medicine, Medicine School, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Carlos Alberto Pereira Tavares
- Department of Biochemistry and Immunology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Ricardo José Alves
- Department of Pharmaceutical Products, Pharmacy School, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Elaine Soares Coimbra
- Department of Parasitology, Microbiology and Immunology, Institute of Biological Sciences, Federal University of Juiz de Fora, Juiz de Fora, Minas Gerais, Brazil
| | - Eduardo Antonio Ferraz Coelho
- Post-graduate Program in Health Sciences: Infectious Diseases and Tropical Medicine, Medicine School, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| |
Collapse
|