title: Chlorin E6 phototoxicity in L. major and L. braziliensis promastigotes-In vitro study.
abstract: BACKGROUND
  Cutaneous leishmaniasis is a zoonosis caused by protozoa of the genus Leishmania. Conventional treatments are long and aggressive, and they trigger a diversity of side effects. Photodynamic Therapy was originally proposed as a treatment for cancer, and it now appears to be a promising therapy for local treatment with fewer side effects of infectious diseases.
  
  
  METHODS
  This study aimed to evaluate Chlorin e6 internalization by Leishmania major and Leishmania braziliensis promastigotes and its viability and effects on mitochondrial activity. Control groups were kept in the dark, while PDT groups received fluence of 10J/cm(2) (660nm). Chlorin internalization was evaluated using confocal microscopy after one hour of incubation for both species.
  
  
  RESULTS
  The mitochondrial activity was evaluated by MTT assay, and viability was measured by the Trypan blue exclusion test. Giemsa staining was used to observe morphological changes. PS was internalized in both species and mitochondrial activity changed in all groups. However, the obtained MTT and Trypan results indicated that despite the change in mitochondrial activity in the dark groups, their viability was not affected, whereas the PDT treated groups had significantly reduced viability. Morphology was drastically altered in PDT treated groups, while groups kept in the dark exhibited the standard morphology.
  
  
  CONCLUSIONS
  This study demonstrates that Chlorin has great potential for being used in PDT as a treatment for cutaneous leishmaniasis, although more studies are needed to determine in vivo application protocols.
authors.affiliation: Laboratório de Terapia Fotodinâmica, Instituto de Pesquisa e desenvolvimento, Univap-Universidade do Vale do Paraíba, Av. Shishima Hifumi, 2911, 12244-000 São José dos Campos, SP, Brazil. Electronic address: jgbiomd@gmail.com.
authors.forename: Juliana Guerra
authors.initials: JG
authors.lastname: Pinto
authors.affiliation: Laboratório de Terapia Fotodinâmica, Instituto de Pesquisa e desenvolvimento, Univap-Universidade do Vale do Paraíba, Av. Shishima Hifumi, 2911, 12244-000 São José dos Campos, SP, Brazil.
authors.forename: André Henrique Correia
authors.initials: AH
authors.lastname: Pereira
authors.affiliation: Laboratório de Parasitologia e Biotecnologia, Instituto de Pesquisa e desenvolvimento, Univap-Universidade do Vale do Paraíba, Av. Shishima Hifumi, 2911, 12244-000 São José dos Campos, SP, Brazil.
authors.forename: Marco Antonio
authors.initials: MA
authors.lastname: de Oliveira
authors.affiliation: Laboratório de Biofotônica, Instituto de Física, USP-Universidade de São Paulo, USP São Carlos-Campus 1, Avenida Trabalhador São-Carlense, 400-Parque Arnold Schimidt, São Carlos, SP 13566, Brazil.
authors.forename: Cristina
authors.initials: C
authors.lastname: Kurachi
authors.affiliation: Laboratório de Nanossensores, Instituto de Pesquisa e desenvolvimento, Univap-Universidade do Vale do Paraíba, Av. Shishima Hifumi, 2911, 12244-000 São José dos Campos, SP, Brazil.
authors.forename: Leandro José
authors.initials: LJ
authors.lastname: Raniero
authors.affiliation: Laboratório de Terapia Fotodinâmica, Instituto de Pesquisa e desenvolvimento, Univap-Universidade do Vale do Paraíba, Av. Shishima Hifumi, 2911, 12244-000 São José dos Campos, SP, Brazil.
authors.forename: Juliana
authors.initials: J
authors.lastname: Ferreira-Strixino
mesh_terms: D002470:Cell Survival / Q000187:drug effects / Q000502:physiology / Q000528:radiation effects; D002735:Chlorophyllides; D004305:Dose-Response Relationship, Drug; D004307:Dose-Response Relationship, Radiation; D006801:Humans; D066298:In Vitro Techniques; D007891:Leishmania / Q000187:drug effects* / Q000502:physiology* / Q000528:radiation effects; D007892:Leishmania braziliensis / Q000187:drug effects* / Q000502:physiology / Q000528:radiation effects; D008027:Light; D008928:Mitochondria / Q000187:drug effects* / Q000502:physiology / Q000528:radiation effects; D010778:Photochemotherapy / Q000379:methods*; D017319:Photosensitizing Agents / Q000008:administration & dosage; D011166:Porphyrins / Q000008:administration & dosage*
chemical_list: D002735:Chlorophyllides; D017319:Photosensitizing Agents; D011166:Porphyrins; C062985:phytochlorin
keywords: Chlorin e6; Leishmania braziliensis; Leishmania major; Photodynamic therapy