过氧化物酶体增殖物激活受体在寻常性银屑病患者表皮中的表达

Expression of peroxisome proliferator-activated receptors in the epidermis of skin from patients with psoriasis vulgaris

目的研究过氧化物酶体增殖物激活受体（PPAR）在寻常性银屑病患者表皮角质形成细胞中的表达和意义。方法采用免疫组化方法检测PPARPPARα、β／δ、γ在5例正常人表皮、17例寻常性银屑病患者皮损及非皮损表皮中的表达，并用图像分析方法进行半定量分析。结果PPARα、β／δ、γ在正常人表皮角质形成细胞中均有不同程度的细胞核表达；在银屑病皮损表皮中的表达强度均较非皮损处下降（P〈0．01）。在银屑病非皮损表皮中，PPARβ／δ、γ的表达强度均较正常人表皮明显升高（P〈0．01）。结论PPARα表达下调可能参与了银屑病表皮角质形成细胞过度增生和分化不全的病理过程，而PPARβ／δ、γ在维持表皮细胞正常增生分化稳态中可能发挥协同作用。

Objective To investigate the expression of peroxisome proliferator-activated receptors （PPARs） in epidermal keratinocytes of patients with psoriasis vulgaris and its significance. Methods Immunohistochemical method was used to examine the expression of PPARα、β/δand γ in tissue specimens from the normal skin of 5 human controls, lesional and normal skin adjacent to the lesions of 17 patients with psoriasis vulgaris. A semi-quantitative analysis was carried out by image analyzer. Results Different levels of expression of the three PPAR isotypes were observed in the nuclei of epidermal keratinocytes of normal human controls. The expression intensity of PPARα、β/δ and γ was statistically higher in the epidermis of adjacent normal skin than that in psoriatic lesions （all P 〈 0.01 ） and normal control skin （all P 〈 0.01 ）. Conclusions The decreased expression of PPARα may be associated with the overproliferation and parakeratosis of epidermal keratinoeytes in psoriatic lesions, and PPARβ/δ and γ may display a synergistic effect on the maintenance of homeostatic proliferation and differentiation of epidermal cells.