Author/Editor     Kansky, A
Title     Keratinization and psoriasis
Type     članek
Source     Acta Dermatovenerol Alp Pannon Adriat
Vol. and No.     Letnik 8, št. 3
Publication year     1999
Volume     str. 89-93
Language     eng
Abstract     The modern concept of the epithelial keratinization includes at least five groups of biologic substrates and the respective molecular processes involved: 1. Keratin, 2. Desmosomes, 3. Cornified cell envelope, 4. Lipids of the horny layer, 5. Signal reception transduction and transcription at the cellular level are also involved in the process of keratinization. Keratins are forming the cytoskeleton of the epidermal cells. Their structure has been extensively studied. A number of anomalies in the structure of keratins K1, K2e, K5,K6a,K9,K10 and K14 have been recognized as causes of various hereditary disorders of keratinization. Mutations in keratin genes are responsible for these events. In psoriatic lesions an increassed expression of keratins K6, K16 and K17 was observed. Desmosomes and its constituents are mainly reponsible for the intercellular adhesion specially in the basal and squamous layers of the epidermis. Deficient desmosomes and their constituents are responsible for the pathology in Mb Darier, in familial benign pemphigus (Mb Hailey-Hailey) as well as in certain acquired bullous dermatoses. Cornified cell envelope (CE) has been only lately recognized as an important structure enabling a normal barrier function. Hereditary deficiency of the enzyme transglutaminase 1 linked to chromosome 14, has been made responsible for about a half the cases of lamellar ichthyosis. The Vohwinkel syndrome has been linked to a genetic anomaly of loricrin, a constituent of CE. Epidermal lipids play an important role in ensuring a normal barrier function of str. corneum: inhibition of penetration of foreign substances, transepidermal water loss. Ceramides and cholesterol are mainly responsible for the regeneration of the barrier function following exposition to solvents and detergents. Splitting of cholesterol esters is important for normal shedding of str corneum. Activation of keratinocytes. (Abstract truncated at 2000 characters.)
Descriptors     PSORIASIS
KERATIN
KERATINOCYTES
DESMOSOMES