人参皂苷Rb1对紫外线损伤的保护作用及其机制研究  

Protective effect of ginsenoside Rbl on ultraviolet B-induced damage and its possible mechanisms

作　　者：蔡宝祥[1,2] 骆丹[1] 

机构地区：[1]南京医科大学第一附属医院皮肤科,210029 [2]宁波医疗中心李惠利医院皮肤科,315040

出　　处：《中华皮肤科杂志》2013年第7期496-500,共5页Chinese Journal of Dermatology

基　　金：国家自然科学基金（30371294）

摘　　要：目的观察人参皂苷Rb1对中波紫外线（UVB）照射诱导小鼠表皮细胞、培养的HaCaT细胞产生与清除环丁烷嘧啶二聚体（CPD）的影响及对核苷酸切除修复蛋白XPC、ERCC1表达的影响。方法42只去毛BALB／c小鼠分为4组：未处理组（6只），UVB组（12只），UVB＋小剂量Rb1组（12只），UVB＋大剂量Rb1组（12只）。后2组照射前2h在背部按100μl／cm2分别外用含0．5g／L、2g／L人参皂苷Rb1的丙酮溶液，而前2组予以相应丙酮溶液。UVB剂量均为180mJ／cm2，于照射后0．5、16h分别处死半数小鼠，利用免疫组化法检测表皮CPD水平。培养的HaCaT细胞用含人参皂苷Rb1（5、20、50mg／L）的培养基孵育4h，部分细胞于UVB照射（15、30mJ／cm2）后0．5、12h终止培养并提取基因组DNA，通过斑点杂交法检测CPD。其余细胞照射（30mJ／cm2）后0、0.5、2、4、12h终止培养，提取细胞总蛋白，通过免疫印迹法分析XPC、ERCC1蛋白的表达。结果UVB照射小鼠0．5h后，各照光组表皮均产生大量CPD，但组间差异无统计学意义；在照射后16h，UVB＋小剂量Rb1组、UVB＋大剂量Rb1组表皮CPD分别为32．1±8．5、14．6±4．1，均较UVB组（67．3±11.2）显著减少，且大剂量组更为明显（P值均〈0．01）。HaCaT细胞在UVB照射后0．5h，各组CPD总量差异无统计学意义，但照射后12h，给药组CPD水平明显降低。UVB组HaCaT细胞XPC、ERCC1蛋白的表达均随着时间延长不断下降，在照射后即刻、0．5、2、4、12h，XPC／GAPDH蛋白灰度比值分别为0．68±0．11、0．47±0．09（与照射后即刻比较，P〈0．05，下同）、0．45±0．08（P〈0．05）、0．37±0．06（P〈0．01）、0．18±0．03（e〈0．01），ERCC1／GAPDH分别为0．28±0．03、0．25±0．03（P〉0．05）、0．21±0．02（P〈0．05）、0．14±0．02（P〈0．01）、0．11±0．01（P〈0．01）；加入50mg／L Rb1干预后，XPC、ERCC1蛋白的表达不断�Objective To estimate the effect of ginsenoside Rbl on the production and clearance of eyclobutane pyrimidine dimer （CPD） as well as on the expression of two nucleotide excision repair-associated proteins, xeroderma pigmentosum group C （XPC） and excision repair cross-complementing group 1 （ERCC1）, by ultraviolet B （UVB）-irradiated murine epidermal cells and human HaCaT keratinocytes. Methods Totally, 42 BALB/c mice were shaved on the back and divided into four groups： untreated group （n = 6）, UVB group irradiated with UVB only （n = 12）, low-dose and high-dose Rbl group （both n = 12） treated with Rbl of 0.5 g/L and 2 g/L （100 μl/cm2） respectively two hours before UVB irradiation. The dose of UVB in the animal experiment was 180 mJ/cm2. Half of the mice in each group were killed at 0.5 and 16 hours respectively after the irradiation, then, the back skin was resected and subjected to the determination of CPD levels in the epidermis by immuno- histochemical SP method. Some cultured HaCaT cells were divided into several groups to be treated with different concentrations （5, 20, 50 mg/L） of Rbl before or after different doses （15 and 30 mJ/cm2） of UVB irradiation, and cells were collected at 0.5 and 12 hours after the irradiation. Subsequently, genomic DNA was extracted and CPD was detected by dot blot hybridization. Some HaCaT cells were cultured with or without the presence of Rbl （50 mg/L） and irradiated with UVB （30 mJ/cm2）, then, the cells were collected immediately or at 0.5, 2,4 and 12 hours after the irradiation, and total protein was extracted and subjected to immunoblot analysis for the quantification of XPC and ERCC1 proteins. Results There was a high level of CPD in the epidermis of mice at 0.5 hour after the irradiation, with no significant differences between these groups （P 〉 0.05）. The number of CPD-positive cells per high power field （× 400） in the marine epidermis at 16 hours was statistically lower in the low- and high-dose Rbl group than

关 键 词：人参皂甙 紫外线 环丁烷嘧啶二聚体 角蛋白细胞 

分 类 号：R28[医药卫生—中药学]