The role of vitamin D in the control of Leishmania infection

Vitamin D has been described as an essential element for maintaining the homeostasis of mineral content in the body and bone architecture. However, our view of the physiological functions of this micronutrient has radically changed, owing to the vast number of properties, not calcium-related, mediated by its nuclear receptor. This receptor has been found in a variety of cells, including the immune cells, where many of the functions performed by vitamin D are related to inflammation. Although the effect of vitamin D has been widely studied in many diseases caused by viruses or bacteria, very little is known about its role in parasitic diseases, such as leishmaniasis, which is a vector-borne disease caused by different species of the intracellular parasite Leishmania spp. This disease occurs as a spectrum of different clinical syndromes, all of them characterized by a large amount of tissue damage, sometimes leading to necrosis. Owing to the involvement of vitamin D in inflammation and wound healing, its role in leishmaniasis must be relevant, and could be used as an adjuvant for the control of this parasitic disease, opening a possibility for a therapeutic application. Key words: 1,25[(OH).sub.2][D.sub.3], leishmaniasis, inflammation, cytokines, immunoregulation, wound healing. On considere que la vitamine D constitue un element essentiel au maintien de l'homeostasie du contenu en mineraux du corps et a l'architecture des os. Cependant, notre vision des fonctions physiologiques de ce micronutriment a radicalement change a cause du grand nombre de proprietes, non reliees au calcium, qui sont relayees par son recepteur nucleaire. Ce recepteur est present dans une variete de cellules incluant les cellules immunitaires, dans lesquelles plusieurs des fonctions exercees par la vitamine D sont reliees a l'inflammation. Meme si l'effet de la vitamine D a ete largement etudie dans plusieurs maladies causees par des virus ou des bacteries, on sait peu de choses de son role dans les maladies parasitaires comme la leishmaniose, une maladie fi transmission vectorielle causee par differentes especes du parasite intracellulaire Leishmania. Cette maladie se manifeste en un spectre de differents symptomes cliniques, tous caracterises par un dommage tissulaire important, conduisant souvent a la necrose. A cause de l'implication de la vitamine D dans l'inflammation et la cicatrisation, son role dans la leishmaniose devrait etre pertinent et elle pourrait etre utilisee comme adjuvant pour controler cette maladie parasitaire, ouvrant une possibilite d'application therapeutique. [Traduit par la Redaction] Mots-cles : 1,25[(OH).sub.2][D.sub.3], leishmaniose, inflammation, cytokines, immunoregulation, cicatrisation.
Introduction The use of vitamin D as a treatment for infections started approximately 150 years ago, although the mechanisms behind this practice were not understood. Over a hundred years ago, [...]