窄谱UVB照射对寻常性银屑病皮损中角质形成细胞P53、半胱天冬酶-3及bax表达的影响

Effect of narrow-band UVB irradiation on expression of P53,casp-3 and bax in keratinocytes of psoriatic lesion

目的:了解窄谱UVB对寻常性银屑病皮损中角质形成细胞P53、半胱天冬酶(casp)-3及bax表达的影响,探讨窄谱UVB治疗银屑病的作用机制。方法:将60例寻常性银屑病患者随机分成对照组、UVBⅠ组和UVBⅡ组3组,分别在光疗前和光疗后4周、8周作银屑病皮损面积和严重度指数(PASI)评分和背部皮损活检,采用免疫组化SABC法检测皮损中P53、casp3及bax表达。结果:UVB I组皮损中P53表达明显低于对照组,UVBⅠ组、UVBⅡ组皮损中casp-3和bax表达明显高于对照组(P<0.01);UVBⅠ组、UVBⅡ组中P53与PASI改善率呈负相关,而casp-3、bax表达呈正相关(P<0.05)。结论:皮损中角质形成细胞P53蛋白表达下调和casp-3、bax表达上调是窄谱UVB治疗寻常性银屑病的作用机制之一。

Objective： To explore the action mechanism of narrow-band （NB）-UVB in psoriasis vulgaris （PV） by detecting the expression of P53, casp-3 and bax in keratinocytes （KC） of psoriastic lesion before and after NB-UVB radiation. Methods： Sixty PV patients were randomly divided into control group, UVB Ⅰ group and UVB Ⅲ group. Each group underwent PASI （psoriasis area and severity index） and skin biopsy before phototherapy and 4 weeks and 8weeks after phototherapy, respectively. Expression of P53, casp-3 and bax was detected by immunohistochemistry （SABC method）. Results： P53 expression was significantly lower in UVBⅠ group than that in control group （P〈 0.05）. Compared with the control group, expression of casp-3 and bax was upregulated in UVB Ⅰ group and UVB Ⅱ group （P 〈 0.01）. There was a negative correlation between P53 expression and improvement rate of PASI, and a positive correlation between casp-3 and bax expression and improvement rate in UVB Ⅰ group and UVB Ⅱ group （P〈 0.05）. Conclusion： Down-expression of P53 and over-expression of casp-3 and bax in KC of psoriatic lesion may be one of action mechanisms of NB-UVB treatment.