Photodynamic therapy for American cutaneous leishmaniasis: the efficacy of methylene blue in hamsters experimentally infected with Leishmania (Leishmania) amazonensis

Exp Parasitol. 2011 Aug;128(4):353-6. doi: 10.1016/j.exppara.2011.04.009. Epub 2011 May 7.

Abstract

The aim of this study was to investigate the effectiveness of Photodynamic Therapy (PDT) using Methylene Blue (MB) as the photosensitizing compound and a Light-Emitting Diode (LED) in American cutaneous leishmaniasis (ACL). Hamsters were experimentally infected with Leishmania (Leishmania) amazonensis. After the development of the lesions in the footpad, the animals were treated with MB three times a week for 3 months. Ten minutes after each application of MB, the lesions were irradiated with LED for 1 h. The lesions were evaluated weekly by the measurement of the hamster footpad thickness. At the end of the treatment the parasitic load was quantified in the regional lymph node of the hamsters. The treatment promoted a decrease in the thickness of infected footpad (P=0.0001) and reduction in the parasitic load in the regional lymph node (P=0.0007) of the animals from group treated with MB+LED. PDT using MB+LED in ACL caused by L. amazonensis shows a strong photodynamic effect. This therapy is very promising, once it is an inexpensive system and the own patient can apply it in their wound and in their house without the need of technical assistance.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cricetinae
  • Enzyme Inhibitors / standards
  • Enzyme Inhibitors / therapeutic use*
  • Leishmania mexicana / drug effects*
  • Leishmaniasis, Cutaneous / drug therapy*
  • Lymph Nodes / parasitology
  • Male
  • Mesocricetus
  • Methylene Blue / standards
  • Methylene Blue / therapeutic use*
  • Photochemotherapy / methods*
  • Photochemotherapy / standards
  • Spleen / parasitology

Substances

  • Enzyme Inhibitors
  • Methylene Blue