摘要目的 探讨外源性胆绿素对中波紫外线(UVB)照射的HaCaT细胞的保护作用及其机制.方法 将培养的HaCaT细胞分为对照组(不加胆绿素,不照射UVB)、UVB组(30 mJ/cm2 UVB照射)和100 nmol/L、1μmol/L、10 μmol/L胆绿素+UVB组(分别于30 mJ/cm2 UVB照射前1h加入相应浓度胆绿素),处理完成后继续培养24 h,观察HaCaT细胞形态变化,CCK8法检测各实验组细胞生存率.Western印迹检测抗氧化信号分子Nrf-2蛋白及光损伤信号分子基质金属蛋白酶1(MMP-1)和MMP-3蛋白表达.结果 CCK8法结果显示,UVB组HaCaT细胞活力低于对照组(P＜0.05),在加入100 nmol/L、1μmol/L、10 μmol/L胆绿素预处理后,细胞生存率逐渐升高,与UVB组比较,差异有统计学意义(均P＜ 0.05).Western印迹显示,UVB组MMP-1(1.150±0.187)、MMP-3(0.979±0.054)蛋白表达较对照组(0.116±0.018、0.636±0.035)升高(均P＜0.01),而100 nmol/L、1μmol/L、10μmol/L胆绿素+ UVB组MMP-1(0.825±0.139、0.313±0.047和0.286±0.036)、MMP-3(0.888±0.017、0.672±0.042和0.569±0.037)蛋白表达较UVB组降低(均P＜0.05).UVB组Nrf-2蛋白(0.906±0.034)较对照组(1.242±0.141)表达降低(P＜0.05),100 nmol/L、1μmol/L、10 μmol/L胆绿素+UVB组Nrf-2蛋白表达(1.556±0.112、1.897±0.234和2.035±0.274)较UVB组升高(均P＜0.01).结论 外源性胆绿素对UVB诱导的HaCaT细胞损伤起保护作用,该作用可能与Nrf-2抗氧化信号通路有关.

abstractsObjective To evaluate the protective effect of exogenous biliverdin on ultraviolet B (UVB)-radiated HaCaT cells,and to explore its mechanism.Methods Cultured HaCaT cells were divided into 5 groups:control group receiving no treatment,UVB group irradiated with 30 mJ/cm2 UVB,3 biliverdin + UVB groups treated with 100 nmol/L,1 μmol/L and 10 μmol/L biliverdin respectively for 1 hour followed by 30 mJ/cm2 UVB radiation.After 24-hour treatment,changes in the morphology of HaCaT cells were observed,and cell counting kit 8 (CCK8) assay was performed to determine cell survival rates in the above groups.Western blot analysis was conducted to measure the protein expression of antioxidant signaling molecule NF-E2-related factor-2 (Nrf-2) and the photodamage signaling molecules matrix metalloproteinase-1 (MMP-1) and MMP-3.Results CCK8 assay showed that the survival rate of HaCaT cells was significantly lower in the UVB group than in the control group (P ＜ 0.05),but significantly higher in the 100-nmol/L,1-μmol/L and 10-μmol/L biliverdin + UVB groups than in the UVB group (all P ＜ 0.05).Western blot analysis showed that the protein expression of MMP-1 and MMP-3 was significantly higher in the UVB group (1.150 ± 0.187,0.979 ± 0.054 respectively) than in the control group (0.116 ± 0.018,0.636 ± 0.035 respectively;both P ＜ 0.01),but was significantly lower in the 100-nmol/L,1-μmol/L and 10-μmol/L biliverdin + UVB groups (MMP-1:0.825 ± 0.139,0.313 ± 0.047 and 0.286 ± 0.036 respectively;MMP-3:0.888 ± 0.017,0.672 ± 0.042 and 0.569:±:0.037 respectively) than in the UVB group (all P ＜ 0.05).Moreover,the protein expression of Nrf-2 was significantly lower in the UVB group (0.906 ± 0.034) than in the control group (1.242 ± 0.141,P ＜ 0.05),but significantly higher in the 100-nmol/L,1-μmol/L and 10-μmol/L biliverdin + UVB groups (1.556 ± 0.112,1.897 ± 0.234 and 2.035 ±0.274) than in the UVB group (all P ＜ 0.01).Conclusion Exogenous biliverdin protects against UVB-induced photodamage in HaCaT cells,which may be associated with Nrf-2 antioxidant signaling pathway.