Vitiligo: pathogenetic hypotheses and targets for current therapies.
Vitiligo is a multifactorial disorder characterized by the appearance of white maculae that may spread over the entire body skin. Depigmentation arises from the loss of functioning melanocytes. Non segmental vitiligo (NSV) is the most common form of the disease: it is usually progressive and may be associated with familiarity and autoimmunity. Segmental vitiligo (SV) frequently stabilizes few years after its onset. Vitiligo etiology involves multiple pathogenetic factors, most of them working in concert. Impaired antioxidative defences lead to accumulation of reactive oxygen species (ROS), which affect melanocytes. Mitochondrial membrane lipid peroxidation may participate to ROS overproduction. A temporal sequence may connect oxidative stress and autoimmunity. Overall, a genetic predisposition renders vitiligo melanocytes more susceptible to precipitating factors than normal healthy melanocytes. The definition of isolated or superimposed manifestations of polygenic skin disorders has been proposed for SV and SV-NSV association. Keratinocytes and melanocytes are both affected and apoptosis, ageing or melanocythorragy are the ultimate effects of the complex deregulation in vitiligo skin. Pathogenetic therapies mainly act by inducing immunosuppression and stimulation of melanocyte proliferation and migration. Here the most popular hypotheses for the pathogenesis of vitiligo are summarized. Fundamental cellular, biochemical and molecular alterations accounting for melanocyte destruction in vitiligo are also described. Last, pathogenetic approaches in the treatment of such a complex disease are discussed, with particular consideration on the cellular and molecular targets of the current therapies.
Guerra
Liliana
L
Tissue Engineering and Cutaneous Pathophysiology Laboratory, Istituto Dermopatico dell'Immacolata, IDI-IRCCS, Via dei Monti di Creta 104, 00167 Rome, Italy. l.guerra@idi.it
Dellambra
Elena
E
Brescia
Serena
S
Raskovic
Desanka
D
D000818:Animals; D000975:Antioxidants / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use; D017209:Apoptosis; D001327:Autoimmune Diseases / Q000188:drug therapy / Q000235:genetics / Q000276:immunology / Q000503:physiopathology; D065095:Calcineurin Inhibitors; D002762:Cholecalciferol / Q000031:analogs & derivatives / Q000494:pharmacology / Q000627:therapeutic use; D003879:Dermatologic Agents / Q000494:pharmacology* / Q000627:therapeutic use*; D004791:Enzyme Inhibitors / Q000494:pharmacology / Q000627:therapeutic use; D020022:Genetic Predisposition to Disease; D006801:Humans; D008544:Melanocytes / Q000187:drug effects / Q000378:metabolism / Q000637:transplantation; D018384:Oxidative Stress / Q000187:drug effects; D010778:Photochemotherapy; D016038:Skin Transplantation; D014820:Vitiligo / Q000188:drug therapy* / Q000235:genetics / Q000276:immunology / Q000503:physiopathology*
D000975:Antioxidants; D065095:Calcineurin Inhibitors; D003879:Dermatologic Agents; D004791:Enzyme Inhibitors; D002762:Cholecalciferol