Abstract:

Objective To investigate the significance of Akt in the pathogenesis of psoriasis. Methods Tissue specimens were obtained from involved and uninvolved skin of 30 patients with progressive psoriasis vulgaris and normal skin of 20 human controls. Immunohistochemistry, immunobloting and kinase activity assay were performed to detect the expressions of Akt and phosphorylated Akt as well as Akt activities in these specimens. Immunostaining intensity was assessed by optical density detection and the results of immunoblot and activity assay by grey scanning. Statistical analyses were performed by variance analysis and student′s t test. Results As immunohistochemistry revealed, there was no significant difference in Akt protein expression among normal epidermis, psoriatic epidermis and uninvolved epidermis （F = 0.611, P > 0.05）; the level of phosphorylated Akt in psoriatic epidermis was significantly higher than that in normal epidermis and psoriatic uninvolved epidermis （F = 19.081, P < 0.01）, while no significant difference was observed between normal epidermis and psoriatic uninvolved epidermis （t = 0.624, P > 0.05）. Immunoblot showed a significant difference in phosphorylated Akt （t = 237.75, P < 0.01） but not in Akt （t = 1.378, P > 0.05） between psoriatic involved epidermis and normal epidermis. In comparison with normal epidermis, the activity of Akt in psoriatic involved epidermis was increased significantly （t = 138.441, P < 0.01）. Conclusion The overproliferation of psoriatic keratinocytes may be associated with increased activation of Akt.

Key words: psoriasis