益母草和枸杞对UVB损伤角质形成细胞的保护作用

目的探讨中草药益母草、枸杞对中波紫外线损伤角质形成细胞的保护作用及作用机制。方法用益母草和枸杞对HaCaT细胞进行预处理24h,采用30mJ/cm2、40mJ/cm2、50mJ/cm2剂量的UVB照射细胞,以MTT法检测细胞生存率,以酶联免疫吸附实验检测细胞上清液中TNF-α的分泌量,以Annexin-V凋亡试剂盒检测细胞凋亡率。结果经UVB照射后,细胞损伤程度与UVB照射剂量有关,益母草和枸杞均可提高UVB照射后角质形成细胞的生存率,减少细胞因子TNF-α的分泌。UVB照射后早期细胞损伤以凋亡为主,晚期以死亡为主,UVB照射8h后益母草和枸杞预处理的HaCaT细胞凋亡率明显减少(P<0.05)。结论UVB对角质形成细胞有损伤作用,且与照射剂量相关,益母草和枸杞对角质形成细胞具有光保护作用。抑制TNF-α的释放和减少细胞凋亡可能是其保护作用机制之一。

Photo-protection of Herba Leonuri and Fructus Lycii on Human Keratinocytes from Ultraviolet Irradiation

Objective To investigate the photo-protective effect of the traditional Chinese medicine (Herba Leonuri and Fructus Lycii) on human keratinocytes from UVB radiation.Methods After pretreated with Herba Leonuri or Fructus Lycii for 24 hours,HaCaT Cells were irradiated with different dosages of UVB.The cell viability was detected by MTT method,The supernatant was collected at 8 and 24 hours post irradiation to measure the secretion of cytokine TNF-α by ELISA.The apoptosis was detected by Annexin-V Apoptosis Kit.Results The cell viability was inverse correlating with the irradiated dosage.Both Herba Leonuri and Fructus Lycii could boost the cell viability,reduce the secretion of TNF-α.The cellular damage was chiefly apoptosis on earlier period and death on advanced stage post-irradiation.Apoptosis rate of pretreated HaCaT cell decreased obviously(P<0.05).Conclusion The damage of UVB irradiation on human keratinocyte was dose-dependent.Herba Leonuri and Fructus Lycii have photo-protective potency.Inhibition of TNF-αsecretion and avoiding apoptosis may be one of the mechanisms for photo-protection.