ABSTRACT
The glutaredoxin system (Grxs) is one of the important antioxidant systems,including glutaredoxin,glutathione,glutaredoxin reductase and nicotinamide adenine dinucleotide phosphate.Glutaredoxin is a small protein as oxidoreductases with the function of deglutathionylation,reducing antioxidants and recombination of iron-sulfur enzymes.In studies of ceils,animals and plants,arsenic and its metabolites can induce reactive oxygen species,generate free radicals and trigger oxidative stress.The Grxs plays an essential role of antioxidant and maintains redox state in arsenic poisoning.Therefore,the article reviewed the anti-oxidation effect of Grxs in arsenic poisoning.
ABSTRACT
Objeetive To observe the damage of human lens epithelial cells (LECs) induced by ultraviolet (UV) B radiation and the expression changes of glutaredoxin 2 (Grx2) in the cells,and to investigate the protective effects of Grx2 on human LECs against UVB-induced apoptosis.Methods Human LECs (HLE-B3) were cultured and exposed to different energy of UVB (0,10,30,50 mJ/cm2) with the wavelength of 297 nm.The morphology of the cells was examined under the optical microscope 2,4,8,12 and 16 hours after irradiation of UVB.The survival rate of the cells was evaluated with cell counting kit 8 (CCK8).The apoptosis rate of the cells was detected by TUNEL assay.Real-time quantitative PCR and Western blot were employed to detect the expressions of Grx2 mRNA and Grx2 protein in the cells,respectively.The cells were transfected with pcDNA3.1-Grx2 plasmid by lipofectamine 2000 as the Grx2 transfected group,and pcDNA3.1 plasmid was transfected into cells as the empty plasmid group.The cells were irradiated by 50 mJ/cm2 for 4 hours,and the apoptosis rate of human LECs was detected by TUNEL assay.Results Cultured cells grew well with the green fluorescence for Grx2 expression in the non-UVB exposure group,and shrinkage and death of the cells were found after UVB irradiation.The survival rate of the cells was gradually reduced after irradiation of 10,30,50 mJ/cm2 UVB as the increase of UVB energy and lapse of time.The expression level of Grx2 mRNA were 2.53±0.48 and 3.53±0.14 in the 10 mJ/cm2 UVB group and 30 mJ/cm2 UVB group 4 hours after irradiation,which were significantly higher than 1.01±0.08 and 1.00±0.09 in the non-UVB exposure group (all at P＜0.05).The expression level of Grx2 mRNA in the cells was 15.30±3.01 at 1 hour after irradiation in the 50 mJ/cm2 UVB group,which was significantly higher than 1.00 ±0.07 in the non-UVB exposure group (P＜0.05).The expression levels of Grx2 protein showed the same tendency to Grx2 mRNA.The apoptosis rate of the cells in the Grx2 transfected group was (15.34± 1.71) ％,and that in the empty plasmid group was (22.11 ± 2.46) ％ at 4 hours after 50 mJ/cm2 UVB irradiation,with a significant difference between them (t =3.189,P ＜ 0.05).Conclusions UVB irradiation induced damage of human LECs in dose-and time-dependent manner.However,the expression of Grx2 in human LECs is up-regulated transiently after exposure of UVB,which has a protective effect on the cells against the UVB-induced apoptosis.
ABSTRACT
Objective To investigate the role of glutaredoxin1(Grx1)on high glucose-induced apoptosis in cultured umbilical vein endothelial cells.Methods Human umbilical vein endothelial cells was cultured and induced with different dose of glucose and Grx1.We divided the cells into three groups:cell control group,damage group(high glucose group),pretreatment with Grx1 group(Grx1+ high glucose group).The morphological changes of the cells were observed by light microscope.The proliferation of cell was measured by MTT assay.The morphon of cell nucleolus of endothelial cell was observed in a fluorescence microscope by Hoechst 33258 stain and the influences of Grx1 on the apoptosis were determined by the immunofluorescent of Annexin V-FITC/PI with flow cytometer.Results Under the light microscope Grx1 ameliorated cells condition and restore the structure of organelle compared with damage group.Grx1 prevented the inhibitory effect on cell viability induced by high glucose;Hoechst33258 stains suggested Grx1 protect the cells nucleolus against high glucose-induced apoptosis.The analysis of Grx1 can restrain apoptosis rate of endothelial cell significantly.Conclusion Grx1 can obviously protect human umbilicus vein endothelial cells from apoptosis damages induced by high glucose.