中文摘要：

目的：观察外源性氧化应激对重构小鼠毛囊新生能力的影响及二苯乙烯苷（TSG，一种中药何首乌活性成分）对新生毛囊的抗氧化保护。方法：用硅胶小室法重构毛囊；用不同辐照剂量（3J／cm2及20J／cm2）长波紫外线（UVA）和不同浓度（100μmol／L及500μmol／L）过氧化氢（H2O2）处理新鲜制备的表皮及真皮细胞，比较观察处理细胞的毛囊新生能力改变，同时用10μmol／LTSG联合500μmol／LH2O2处理细胞，观察其抗氧化能力：毛囊重构部位皮肤活检采用苏木精-伊红（HE）染色进行毛囊计数，免疫组化法测定皮肤标本过氧化氢酶（CAT）表达；电子自旋共振（ESR）测试TSG羟自由基清除活性。结果：3J／cm2 UVA照射组重建毛囊密度为（304±11．79）个，20J／cm2 UVA为（135±11．24）个，与对照组（202±11．79）个比较，差异有统计学意义（P〈0．05）；500μmol／LH2O2组毛囊密度为（109±20．50）个，500μmol／LH2O2联合10μmol／LTSG处理组为（207±15．01）个。联合处理组与对照组（216±10．26）比较，差异无统计学意义（P〉0．05）。免疫组化结果显示500μmol／LH2O2处理组CAT染色强度18．67±2．17较对照组26．07±3．74明显减低，而500μmol／LH2O2联合10μmol／LTSG处理组50．02±3．82较对照组增强（P〈0．05）；ESR结果示TSG自身缺乏羟自由基清除活性。结论：不同水平的氧化应激对重构小鼠毛囊新生能力影响不同，低水平刺激而高水平则抑制毛囊生长。TSG对小鼠重构毛囊的抗氧化保护可能是通过上调皮肤细胞（主要是真皮细胞）CAT的表达。

英文摘要：

Objective： To investigate the effect of exogenous oxidative stress on the neogenic ability of the reconstituted hair follicles in mice as well as the anti-oxidative effect of Stilbene-glycoside（TSG, an active ingredient of Radix polygoni muhiflora） for neo-generative hair follicles. Methods： A silicon chamber method was used for hair follicle reeonstitution in mice. Epidermal keratinocytes and fibroblasts from newborn mice were irradiated with UVA （3,20 J/cm2）, or treated with either H2O2 （100, 500 μmol/L） alone or the combination of 10 μmol/L TSG and 500 μmol/L H2O2. The neogenie ability of neo-generative hair follicles and the density of hair follicles were assessed histologically. Immunohistoehemieal staining was used to assess the expression of catalase（CAT）. Meanwhile, the scavenging activity of TGS against hydroxyl free radical was determined using an electron spin resonance（ESR）. Results： UVA irradiation significantly changed the densities of reconstituted hair follicles（202±11.79） for normal controls; 304±11.79 for 3J/cm2 and 135±11.24 for 20J/cm2; P〈0.05 for normal vs. both irradiated groups）. Addition of 10 μmol/L TSG normalized the density of follicles in 500 μmol/L H2O2-treated cells（Normal controls： 216±10.26; 500 μmol/L H2O2： 109±20.50; 500 μmol/L H2O2 plus 10 μmol/L TSG： 207±15.01. The intensity of CAT staining significantly decreased in 500 μmol/L H2O2-treated （18.67±2.17） compared with normal eontrols（26.07±3.74）（P〈0.05）. Increased CAT expression was noted in the TGS plus H2O2 group（50.02±3.82）, P〈0.05 vs. normal controls）. No scavenging activity of TGS against hydroxyl free radical was detected by ESR assay. Conclusions： Low extent of oxidative stress stimulates neogenesis of reconstituted hair follicles while high extent of oxidative stress inhibits neogenesis. TSG protects reconstituted hair follicles a- gainst oxidative stress via up-regulation of CAT expression in skin, particularly in the dermis.