【摘要】 目的探讨扇贝多肽对单次长波紫外线辐射HaCaT角质形成细胞氧化损伤的保护作用机制。方法从栉孔扇贝中提取扇贝多肽(PCF,Mr=879)。UVA辐射强度为5J·cm-2。酶生化法测定胞质SOD,GSH-px活性,ROS、MDA水平;透射电镜观察细胞超微结构的改变;原位杂交技术检测细胞内p21mRNA的变化。结果在5J·cm-2UVA辐射下,在给定浓度范围内PCF能剂量依赖性降低胞质ROS、MDA水平;提高SOD,GSH-px活力;电镜下可见PCF可保护细胞超微结构;p21mRNA原位杂交发现PCF可明显抑制其表达。结论扇贝多肽对单次UVA诱导的人HaCaT细胞氧化损伤有保护作用。其机制与清除氧自由基、提高抗氧化酶活性、抑制p21mRNA表达及细胞凋亡有关。更多还原

【Abstract】 Aim To investigate the protective effect of PCF on the oxidative damages induced by single UVA in HaCaT keratinocytes. Methods Polypeptide from Chlamys farreri (PCF,Mr=879) was isolated from Chlamys farreri using marine enzymetically engineering technique. The cells were randomly divided into seven groups. The intracellular SOD, GSH-px, MDA and ROS were measured using biochemical methods.The ultrastructures of HaCaT keratinocytes were observed under transmission electron microscope. In situ hybridization was used to examine the changes of p21mRNA expression. Results PCF markedly increased the activities of SOD and GSH-px, decreased the amounts of MDA and ROS. PCF greatly decreased UVA-induced damage, especially membrane injuries. p21mRNA expression was inhibited in PCF groups. All results were in a dose-dependent manner. Conclusion PCF could reduce UVA-induced oxidative damage on HaCaT keratinocytes. The mechanism were due to its abilities to scavenge oxygen free radical, inhibit lipid peroxidation, increase anti-oxidative enzymes, protect the membrane structure, and block the expression of p21mRNA.更多还原