Measurement of Serum Lipocalin-2 in Psoriasis Vulgaris Patients Before & After Treatment with Narrow Band Ultraviolet-B

Abstract

Psoriasis is a chronic inflammatory, immune-mediated skin condition characterized by sharply demarcated, erythematous, and scaly symmetrical plaques on the elbows, knees or scalp.Although the precise pathomechanism remains unknown, various cytokines and growth factors are involved in this disease.TNF-α is a pleiotropic inflammatory cytokine, andstudies indicate that TNF-α plays a critical role in the development of psoriasis. Psoriasis vulgaris is associated with several risk factors for cardiovascular diseases namely, increased oxidative stress, dyslipidaemia, inflammation, and more recently, with overweight and obesity. The lipocalins are a family of proteins which transport small hydrophobic molecules such as steroids, retinoids, and lipids. They share limited regions of sequence homology and a common tertiary structure architecture. Lipocalin proteins are involved in inflammation and detoxification processes caused by immune system activation in mammals. Neutrophil gelatinase-associated lipocalin (NGAL) or lipocalin 2 is a 25- kDa protein initially isolated from the specific granules of human neutrophil,also it is most abundantly produced from adipocytes .NGAL is linked to either keratin synthesis or terminal differentiation. Strong induction of NGAL in the epidermis was seen in a variety of skin disorders characterized by dysregulated epithelial differentiation such as psoriasis. Production of NGAL was confined to spatially distinct subpopulations of keratinocytes underlying areas of parakeratosis, whereas skin samples lacking parakeratotic epithelium such as lichen planus were negative for NGAL. The biologic functions of NGAL in epithelia are not fully known. In addition, the transient interfollicular NGAL expression during skin embryogenesis along with the induction of NGAL in adult parakeratotic epidermis suggests that it plays a role in epithelial differentiation pathways.Although an immunomodulatory role in host defense has been proposed, NGAL also have a role as bacteriostatic agent through iron transportation leading to deprivation of bacteria from iron. Another role of NGAL is a survival factor through regulating of iron uptake in to cells. NGAL was isolated as a potential biomarker of acute and chronic kidney injury and protection from injury. It's also consider key event that contribute to neaplasia