Crocin prevents the apoptosis of retinal microvascular endothelial cells induced by advanced glycosylation end products
GUO Bin1,FAN Qin-hua1,WANG Li2,ZHANG Zhi-qiang1,LIU Xiao-juan3(1.Department of Ophthalmology,The 81st Hospital of PLA,Nanjing 210002,Jiangsu,China;2.Research Institute of Field Surgery,Daping Hospital,The 3rd Military Medical University,Chongqing 400042,China;3.Department of Ophthalmology,Laoshan Clinic,The 401st Hospital of PLA,Qingdao 266102,Shandong,China)
Objective Advanced glycosylation end products(AGE) in diabetic retinopathy may result in the production of reactive oxygen species(ROS) and inflammation cytokines,which cause apoptosis of retinal microvascular endothelial cells(RMEC) and loss of visual function.The authors investigated the effects of crocin on the viability,apoptosis,and ROS production,intracellular and supernatant tumor necrosis factor(TNF)-α level of AGE-induced RMECs in rats,as well as the protective mechanism of crocin in AGE-induced RMEC apoptosis.Methods Rat RMECs were isolated using magnetic beads and cultured in the crocin medium at the concentrations of 0,10,50 and 100 μmol/L,respectively.The proliferation curves of the RMECs were recorded within 4 days.The RMECs treated with 100 mg/L AGE were exposed to various concentrations of crocin.The viability of the RMECs was measured after trypan blue staining,their apoptosis rate detected by flow cytometry,the intracellular ROS products determined by fluorescence enzyme-labeled meter,and the levels of intercellular and supernatant TNF-α measured by protein electrophoresis and ELISA.Results The proliferation of the RMECs continued in the 10 and 50 μmol/L crocin media,but was inhibited in the 100 μmol/L crocin medium at 3 and 4 days.Compared with the normal control group,the viability of the RMECs was decreased after treated with 100 mg/L AGE for 12 and 24 hours.Crocin at 10,50 and 100 μmol/L protected the viability of the RMECs.The apoptosis rate of the RMECs was significantly increased after treated with 100 mg/L AGE for 12 hours,but remarkably decreased after treated with crocin at 10,50 and 100 μmol/L for 12 hours.AGE markedly elevated the level of ROS in the RMECs(P0.01),and 10,50 and 100 μmol/L of crocin variably reduced the production of ROS in the AGE-induced RMECs.The TNF-α levels in the RMECs and supernatant were obviously raised after treated with AGE,but significantly suppressed by crocin at 10,50 and 100 μmol/L.Conclusion Crocin can prevent the apoptosis RMECs inhibiting AGE-induced ROS production and reducing the synthesis of TNF-α.
【CateGory Index】： R29
【CateGory Index】： R29