title: Cell accumulation and antileishmanial effect of exogenous and endogenous protoporphyrin IX after photodynamic treatment.
abstract: BACKGROUND
  Photodynamic therapy (PDT) using 5-aminolevulinic acid-induced protoporphyrin IX (ALA-PpIX) constitutes an interesting alternative for cutaneous leishmaniasis treatment.
  
  
  OBJECTIVE
  To evaluate the production of PpIXbased on the administration of ALA and MAL and the effect of ALA-PDTat cellular level on non-infected and infected THP-1 cells using Leishmania ( Viannia ) panamensis or Leishmania ( Leishmania ) infantum (syn Leishmania chagasi ) parasites.
  
  
  METHODS
  Protoporphyrin IX (PpIX) production and mitochondrial colocalization were evaluated by confocal microscopy. Cell toxicities were evaluated after treatment with the compounds, followed by light irradiation (597-752 nm) at 2.5 J/cm 2 fluency using a colorimetric MTT assay for THP-1 cells and a standard microscopic analysis of parasites. RESULTS were expressed as compound concentration activity against 50% of cells or parasites (CC 50 or IC 50 ).
  
  
  RESULTS
  ALA or MAL induced an endogenous PpIX with a red fluorescence localized mainly in the mitochondria inside human cells. ALA and MAL-PDT induced a similar range of toxicities on THP-1 cells (CC 50 0.16 ± 0.01 mM and 0.33 ± 0.019 mM, respectively) without any apparent inhibition of intracellular parasites in the infected cells as compared to untreated controls. Exogenous PpIX-PDT was toxic to THP-1 cells (CC 50 0.00032 ± 0.00002 mM), L. (L.) infantum (IC 50 0.003 ± 0.0001 mM) and L. (V.) panamensis (IC 50 0.024 ± 0.0001 mM) promastigotes.
  
  
  CONCLUSIONS
  Despite the effectiveness of exogenous PpIX on promastigotes and the production of PpIX by human infected cells, treatment with ALA or MAL before irradiation was unable to completely destroy L. (L.) infantum or L. (V.) panamensis intracellular amastigotes.
authors.affiliation: Centro de Investigación de Enfermedades Tropicales (CINTROP), Escuela de Medicina, Departamento de Ciencias Básicas, Universidad Industrial de Santander, Bucaramanga, Colombia.
authors.forename: Jairo E
authors.initials: JE
authors.lastname: Mateus
authors.affiliation: Centro de Investigación de Enfermedades Tropicales (CINTROP), Escuela de Medicina, Departamento de Ciencias Básicas, Universidad Industrial de Santander, Bucaramanga, Colombia.
authors.forename: Wilfredo
authors.initials: W
authors.lastname: Valdivieso
authors.affiliation: Centro de Investigación de Enfermedades Tropicales (CINTROP), Escuela de Medicina, Departamento de Ciencias Básicas, Universidad Industrial de Santander, Bucaramanga, Colombia.
authors.forename: Indira P
authors.initials: IP
authors.lastname: Hernández
authors.affiliation: Centro de Investigación en Catálisis (CICAT), Escuela de Química, Universidad Industrial de Santander, Bucaramanga, Colombia.
authors.forename: Fernando
authors.initials: F
authors.lastname: Martínez
authors.affiliation: Centro de Investigación en Catálisis (CICAT), Escuela de Química, Universidad Industrial de Santander, Bucaramanga, Colombia.
authors.forename: Edgar
authors.initials: E
authors.lastname: Páez
authors.affiliation: Centro de Investigación de Enfermedades Tropicales (CINTROP), Escuela de Medicina, Departamento de Ciencias Básicas, Universidad Industrial de Santander, Bucaramanga, Colombia.
authors.forename: Patricia
authors.initials: P
authors.lastname: Escobar
mesh_terms: D000622:Aminolevulinic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology* / Q000528:radiation effects; D000666:Amphotericin B / Q000494:pharmacology; D045744:Cell Line, Tumor; D003124:Colorimetry; D006801:Humans; D018334:Leishmania guyanensis / Q000187:drug effects*; D018314:Leishmania infantum / Q000187:drug effects*; D007948:Leukemia, Monocytic, Acute / Q000473:pathology; D008247:Lysosomes / Q000737:chemistry; D008856:Microscopy, Fluorescence; D008928:Mitochondria / Q000737:chemistry; D009000:Monocytes / Q000187:drug effects* / Q000469:parasitology / Q000648:ultrastructure; D010778:Photochemotherapy; D017319:Photosensitizing Agents / Q000494:pharmacology* / Q000528:radiation effects; D011524:Protoporphyrins / Q000032:analysis*; D013045:Species Specificity; D013347:Subcellular Fractions / Q000737:chemistry / Q000187:drug effects*
chemical_list: D017319:Photosensitizing Agents; D011524:Protoporphyrins; C475457:methyl 5-aminolevulinate; D000666:Amphotericin B; D000622:Aminolevulinic Acid; C028025:protoporphyrin IX