Environmental risk factors and epigenetic alternations in psoriasis
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Dermatology Department of Centre of Postgraduate Medical Education, Warsaw, Poland
Center of Reproductive Health, Institute of Mother and Child, Warsaw, Poland Department of Obstetrics and Gynecology CSKMSWiA, Warsaw, Poland
Marek Roszkiewicz   

Dermatology Department of Centre of Postgraduate Medical Education
Introduction and objective:
Psoriasis isa quite common, chronic and immune-mediated skin disorder. The prevalence of psoriasis differs in various countries, but it is said to affect 2% of the world’s population in general. Psoriasis has many different clinical features but all lesions have the same characteristic: erythema, thickening and scale, although other clinical features are also connected, such as psoriatic arthritis, obesity and metabolic syndrome. All of these may lead to conditions impairing the quality of life. This review is an attempt to summarize recent data regarding environmental factors, together with epigenetic markers and processes playing an important role in psoriasis.

State of knowledge:
Many different environmental factors play a role in genetically predisposed patients. This is causes epigenetic alternations which may be a linking part in the whole process. Many studies have indicated a connection between psoriasis and various genes and antigens. The presence of HLA-Cw6 is common as well a strong link between its presence and the onset of psoriasis being observed. The main alternations are DNA methylation, histone’s modifications and the role of microRNA. Excessive reaction is usually not present without a triggering factor. Environmental factors are mostly rated, such as drugs, life style and habits (smoking, alcohol), diet, physical trauma (skin injury provoking Koebner phenomenon), stress, microorganism and infections.

The correlation between pathogenesis of psoriasis and environmental risk factors, together with epigenetic alternations still require more investigation. Education about diet habits, nutrition, weight loss and healthy lifestyle seems to be important during the treatment of psoriasis.

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