The Expression Of GR In The Psoriatic Epidermal Keratinocytes

BackgroundPsoriasis, a common chronic inflammatory skin disease characterized by keratinocyte hyperplasia and abnormal differentiation, due to the joint influences of genetic and environmental factors. Exacerbation of psoriasis is relevant with the dysfunction of infectious, mental, neurological, immune and endocrine systems. Fan jianyong, after measuring the expression of glucocorticoid receptor (GR) in white blood cell with RT-PCR, a semi-quantitative method, found that of GR mRNA in psoriasis was significantly lower than control groups. Clinically, glucocorticoid (GC) is effective in the treatment of psoriasis but proning to rebound, suggesting the abnormalities of the GC, GR in psoriasis.ObjectiveTo define the role of GR in the pathogenesis of psoriasis by detecting the expression and localization of the psoriatic epidermal keratinocytes and normal skin epidermal keratinocytes and to further explore the mechanism of GC treatment of psoriasis in hope of laying the foundation for the prevention of GC adverse reaction.Methods15 patients with moderate to severe plaque psoriasis were included. Skin samples from lesion and normal tissues were divided into 2 portions: one is for psoriatic and normal epidermal keratinocytes culture, the other part was for immunostaining. mRNA and protein levels of GR were determined by RT-PCR and Western blot, seperately.ResultsGR mRNA (GR / GAPDH) in psoriatic epidermal keratinocyte is detected as 0. 687 and that in normal epidermal keratinocyte 0.478. The GR mRNA in psoriatic epidermal keratinocytes is higher than normal control group and the difference is significant (P<0.05). Through Western blot, the level of the GR band ((OD×S) / (od×s)) of psoriatic epidermal keratinocyte is detected as 0.467, and that of the normal control group 0.212. The expression of GR in psoriasis group is higher than the normal control group, and there is a significant difference (P<0.05). Immunofluorescence shows that the distribution of GR in psoriatic skin has been changed in the following aspects: normal epidermal keratinocytes of all layers and psoriatic basal keratinocytes are mainly located in the nucleus. However, in the psoriatic spinous keratinocytes, GR is mainly in the cytoplasm. ConclusionThe overexpression of GR in psoriatic epidermal keratinocyte, as well as its translocation indicates that GR plays a role in the pathogenesis of psoriasis.