title: The Effect of Ursolic Acid on Leishmania (Leishmania) amazonensis Is Related to Programed Cell Death and Presents Therapeutic Potential in Experimental Cutaneous Leishmaniasis.
abstract: Among neglected tropical diseases, leishmaniasis is one of the most important ones, affecting more than 12 million people worldwide. The available treatments are not well tolerated, and present diverse side effects, justifying the search for new therapeutic compounds. In the present study, the activity of ursolic acid (UA) and oleanolic acid (OA) were assayed in experimental cutaneous leishmaniasis (in vitro and in vivo). Promastigote forms of L. amazonensis were incubated with OA and UA for 24h, and effective concentration 50% (EC50) was estimated. Ultraestructural alterations in Leishmania amazonensis promastigotes after UA treatment were evaluated by transmission electron microscopy, and the possible mode of action was assayed through Annexin V and propidium iodide staining, caspase 3/7 activity, DNA fragmentation and transmembrane mitochondrial potential. The UA potential was evaluated in intracellular amastigotes, and its therapeutic potential was evaluated in L. amazonensis infected BALB/c mice. UA eliminated L. amazonensis promastigotes with an EC50 of 6.4 μg/mL, comparable with miltefosine, while OA presented only a marginal effect on promastigote forms at 100 μg/mL. The possible mechanism by which promastigotes were eliminated by UA was programmed cell death, independent of caspase 3/7, but it was highly dependent on mitochondria activity. UA was not toxic for peritoneal macrophages from BALB/c mice, and it was able to eliminate intracellular amastigotes, associated with nitric oxide (NO) production. OA did not eliminate amastigotes nor trigger NO. L. amazonensis infected BALB/c mice submitted to UA treatment presented lesser lesion size and parasitism compared to control. This study showed, for the first time, that UA eliminate promastigote forms through a mechanism associated with programed cell death, and importantly, was effective in vivo. Therefore, UA can be considered an interesting candidate for future tests as a prototype drug for the treatment of cutaneous leishmaniasis.
authors.affiliation: Laboratory of Pathology of Infectious Diseases (LIM50), Department of Pathology, Medical School of São Paulo University, Av. Dr. Arnaldo, 455. Cerqueira César, São Paulo, 01246-903, SP, Brazil.
authors.forename: Eduardo S
authors.initials: ES
authors.lastname: Yamamoto
authors.affiliation: Laboratory of Pathology of Infectious Diseases (LIM50), Department of Pathology, Medical School of São Paulo University, Av. Dr. Arnaldo, 455. Cerqueira César, São Paulo, 01246-903, SP, Brazil.
authors.forename: Bruno L S
authors.initials: BL
authors.lastname: Campos
authors.affiliation: Laboratory of Pathology of Infectious Diseases (LIM50), Department of Pathology, Medical School of São Paulo University, Av. Dr. Arnaldo, 455. Cerqueira César, São Paulo, 01246-903, SP, Brazil.
authors.forename: Jéssica A
authors.initials: JA
authors.lastname: Jesus
authors.affiliation: Laboratory of Pathology of Infectious Diseases (LIM50), Department of Pathology, Medical School of São Paulo University, Av. Dr. Arnaldo, 455. Cerqueira César, São Paulo, 01246-903, SP, Brazil.
authors.forename: Márcia D
authors.initials: MD
authors.lastname: Laurenti
authors.affiliation: Laboratory of Clinical Immunology and Allergy (LIM60), University of São Paulo, School of Medicine. Av. Dr. Arnaldo, 455. Cerqueira César, São Paulo, Brazil.|Department of Pathology, Case Western Reserve University, 2103 Cornell Rd, Cleveland, OH 44106, United States of America.
authors.forename: Susan P
authors.initials: SP
authors.lastname: Ribeiro
authors.affiliation: Laboratory of Clinical Immunology and Allergy (LIM60), University of São Paulo, School of Medicine. Av. Dr. Arnaldo, 455. Cerqueira César, São Paulo, Brazil.
authors.forename: Esper G
authors.initials: EG
authors.lastname: Kallás
authors.affiliation: Global Health and Tropical Medicine, Instituto de Higiene e Medicina Tropical (IHMT), Universidade Nova de Lisboa, Rua da Junqueira 100, 1349-008 Lisboa, Portugal.
authors.forename: Mariana
authors.initials: M
authors.lastname: Rafael-Fernandes
authors.affiliation: Global Health and Tropical Medicine, Instituto de Higiene e Medicina Tropical (IHMT), Universidade Nova de Lisboa, Rua da Junqueira 100, 1349-008 Lisboa, Portugal.
authors.forename: Gabriela
authors.initials: G
authors.lastname: Santos-Gomes
authors.affiliation: Global Health and Tropical Medicine, Instituto de Higiene e Medicina Tropical (IHMT), Universidade Nova de Lisboa, Rua da Junqueira 100, 1349-008 Lisboa, Portugal.
authors.forename: Marcelo S
authors.initials: MS
authors.lastname: Silva
authors.affiliation: Institute of Environmental, Chemical and Pharmaceutical Sciences - Federal University of São Paulo, Rua São Nicolau, 210, 09920-000, Diadema, SP, Brazil.
authors.forename: Deborah P
authors.initials: DP
authors.lastname: Sessa
authors.affiliation: Institute of Environmental, Chemical and Pharmaceutical Sciences - Federal University of São Paulo, Rua São Nicolau, 210, 09920-000, Diadema, SP, Brazil.
authors.forename: João H G
authors.initials: JH
authors.lastname: Lago
authors.affiliation: Laboratory of Genetics and Molecular Hematology (LIM31), University of São Paulo, School of Medicine. Av. Dr. Enéas de Carvalho Aguiar, 155. Cerqueira César, São Paulo, Brazil.
authors.forename: Débora
authors.initials: D
authors.lastname: Levy
authors.affiliation: Laboratory of Pathology of Infectious Diseases (LIM50), Department of Pathology, Medical School of São Paulo University, Av. Dr. Arnaldo, 455. Cerqueira César, São Paulo, 01246-903, SP, Brazil.
authors.forename: Luiz F D
authors.initials: LF
authors.lastname: Passero
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D016207:Cytokines / Q000096:biosynthesis; D004195:Disease Models, Animal; D005260:Female; D007891:Leishmania / Q000187:drug effects* / Q000648:ultrastructure; D016773:Leishmaniasis, Cutaneous / Q000188:drug therapy / Q000469:parasitology* / Q000473:pathology; D017737:Macrophages, Peritoneal / Q000187:drug effects / Q000378:metabolism / Q000469:parasitology; D008297:Male; D051379:Mice; D009569:Nitric Oxide / Q000378:metabolism; D009828:Oleanolic Acid / Q000494:pharmacology; D010936:Plant Extracts / Q000494:pharmacology; D014315:Triterpenes / Q000494:pharmacology*; D014344:Trypanocidal Agents / Q000494:pharmacology*; D000097245:Ursolic Acid
chemical_list: D016207:Cytokines; D009569:Nitric Oxide; D009828:Oleanolic Acid; D010936:Plant Extracts; D014315:Triterpenes; D014344:Trypanocidal Agents; D000097245:Ursolic Acid