不同剂量UVA1光疗对免疫接触性致敏小鼠皮肤光损伤的影响

Effect of different doses of UVA1 phototherapy on skin photodamage in immune-contact sensitized mice

目的探讨不同剂量长波紫外线1(UVA1)照射对皮肤造成的损伤程度,平衡UVA1光疗作用与光损伤的关系,以期获得治疗的最大效益。方法模拟不同剂量UVA1照射治疗免疫接触性致敏小鼠模型,观察治疗过程中皮肤的光损伤程度并对光损伤相关指标进行检测。结果随着剂量和照射次数的增加,皮肤出现黑斑的小鼠比例高于无晒伤表现或红斑的小鼠(P<0.05),但皮肤厚度和组织形态学与未照光免疫接触性致敏小鼠模型组相比均无明显改变。皮肤丙二醛(MDA)和还原型谷胱甘肽(GSH)检测显示,随着照射剂量和照射次数的增加,小鼠皮肤MDA含量也随之升高(P<0.05);对GSH而言,随着照射剂量的增大,小鼠皮肤GSH含量下降(P<0.05);不同的照射次数对小鼠皮肤GSH含量无明显影响。结论不同剂量的UVA1光疗均可造成皮肤光损伤,并随着剂量和次数的增加而损伤加重。但短期内这种光损伤是轻微的,尤其是低剂量UVA1照射,中高剂量UVA1照射则需考虑光疗作用与光损伤的平衡。

Objective To evaluate the degree of skin injury caused by different doses of UVA1 irradiation and balance the relationship between UVA1 phototherapy and photodamage,aiming to maximize the therapeutic benefits.Methods Different doses of UVA1 irradiation were simulated to treat immune-contact sensitized mouse models.The degree of skin photodamage during treatment was observed and photodamage-related indexes were detected.Results With the increase of dose and irradiation times,the proportion of mice with black spots on the skin was significantly higher than that of mice without sunburn or erythema(both P<0.05).However,there were no significant changes in skin thickness and histomorphology compared with the non-photosensitized mouse model group.The detection of malondialdehyde(MDA)and reduced glutathione(GSH)on the skin showed that the increase of doses and irradiation times would cause the increase of MDA content(P<0.05);For GSH,the increase of doses would cause the decrease of GSH content(P<0.05);and the irradiation time exerted no effect(P>0.05).Conclusions Different doses of UVA1 phototherapy can cause skin photodamage,which is aggravated with the increase of dose and frequency.However,this photodamage is mild in the short term,especially with low-dose UVA1 irradiation.The balance between phototherapy effect and photodamage needs to be considered for moderate-and high-dose UVA1 irradiation.