Up-regulation of corticotropin releasing hormone is associated with the downregulation of corticotropin releasing hormone binding protein and up-regulation of IL- 33 and IL-8 expression in psoriasis

Fei Su,Yun Xia,Meng Huang,Liuqing Chen,Liang Zhang

doi:10.4314/tjpr.v16i11.4

Abstract

Purpose : To determine the expression of corticotropin-releasing hormone (CRH) in psoriasis and normal skin biopsy samples, and to correlate the expression of CRH with the expression of CRHBP and inflammatory cytokines IL-8 and IL-33. Methods : Psoriasis and normal skin biopsy samples were obtained from three psoriatic and three normal healthy patients. The mRNA expression was examined by quantitative real-time polymerase chain reaction (qRT-PCR). Protein expression analysis was carried out by western blotting and then further validated by immunohistochemistry. Results : The results revealed that the expression of CRH was highly significantly (p < 0.0001) in psoriatic skin samples compared to normal skin samples. The increase of CRH in psoriatic samples ranged from 2.7- to 3.5-fold. Expression of CRH was associated with concomitant downregulation of CRHBP in all the psoriatic skin biopsy samples. Expression of CRHBP was 3- to 6.2-fold lower in psoriatic samples compared to normal skin samples. Analysis of mRNA expression of IL-8 and IL-33, revealed that expression of both IL-8 and IL-33 was significantly (p < 0.0001) upregulated in psoriatic skin samples. Expression of IL-8 and IL-33 was approximately 4.1 and 3.2-fold higher in psoriatic skin samples than in normal skin samples. Expression of CRHBP, IL-8 and IL-33 was further confirmed by western blotting and immunohistochemistry which the findings from quantitative RT-PCR. Conclusion : Taken together, the results confirm that the expression of CRH is associated with suppression of CRHBP and upregulation of IL-8 and IL-33. Keywords : Psoriasis, Corticotropin releasing hormone, Inflammatory cytokines, Interleukin, Skin biopsy

Highlights

Psoriasis is one of the chronic inflammatory skin disorders that affect around 3 % of the human population around the globe
It is well reported that expression of corticotropin releasing hormone (CRH) is induced under stress conditions, we evaluated the expression of CRH in healthy and psoriatic skin biopsy samples
We evaluated the expression of CRHBP in psoriatic and normal skin biopsy samples by quantitative real-time polymerase chain reaction (RT-PCR)

Summary

Introduction

Psoriasis is one of the chronic inflammatory skin disorders that affect around 3 % of the human population around the globe. Studies have reported that the incidence of psoriasis may vary with race and geographical locality and the environmental conditions [1,2]. Psoriasis has broad clinical spectra ranging from the involvement of skin to erythroderma [3]. Psoriasis has been categorized into two different types. Type I psoriasis is genetic, usually arises at or around the age of 16 years in females and 22 years in males. Type II psoriasis is sporadic and generally affects the people around 60 years of age [4]. The development of psoriatic plaques triggers pain and generates a lot of discomfort [5]

Results

Discussion

Conclusion