Effects Of Cytoglobin On Oxldl-Induced Endothelial Cell Injury And Its Mechanism

[Object] Cytoglobin(CYGB) is an anti-oxidative stress globin, that can protect cells by anti-oxidative stress. This study is to observe changes of cytoglobin expression and to explore the protective role of CYGB during the process of oxidaive stress via overexpression and downexpression of CYGB in Human Umbilical Vein Endothelial Cells(HUVECs). [Method]1. HUVECs were observed by an inverted microscope. 2. Western blot was used to detect CYGB expression after oxLDL treatment at different concentrations for 24 h. The HUVECs were divided into four groups: control group, 25μg/ml oxLDL, 50μg/ml oxLDL, 100μg/ml oxLDL,200μg/ml oxLDL-treated group. The HUVECs were divided into four groups: control group, 100μg/ml ox LDL treatment with 4,8, 12, 24 h group.Then, CYGB expression was detected by western blot. 3. The HUVECs were divided into four groups:control group,100μg/ml oxLDL-treated group, 100μg/ml oxLDL treatment+CYGB expression group and 100μg/ml oxLDL treatment+CYGB interference group. CYGB protein levels, glutathione peroxidase(GSH-PX), lactate dehydrogenase(LDH), malondialdehyde(MDA), superoxide dismutase(SOD), Bcl2 and Bax protein levels in each group were detected. 4. To observe the effects of PKC signal pathway on HUVECs injure induced by oxLDL. HUVECs were divided into 3 groups: control group, 100μg/ml oxLDL treatment group, 100μg/ml oxLDL+Staurosporine group. CYGB protein levels, GSH-PX, LDH, MDA, SOD, Bcl2 and Bax protein levels were detected. [Results]1. Inverted microscope showed that HUVECs cultures like cobblestone. 2. Western blot showed that 0, 25μg/ml oxLDL,50μg/ml oxLDL, 100μg/ml oxLDL treatment with 24 h induces. CYGB expression, the difference has statistics significance(P <0.05); 100μg / ml oxLDL treatment with 4,8,12,24 h induces. CYGB expression significantly. It was highest level in 24 h group(P <0.05). 3. Western blot results showed that transfection with CYGB plasmids increased CYGB expression significantly; transfection with CYGB shRNA elecreased CYGB expression significantly. 4. Western blot results showed that CYGB expression in 100μg/ml oxLDL group, and 100μg/ml oxLDL+CYGB group was higher than normal control group, and CYGB protein expression in 100μg/ml oxLDL+CYGB shRNA group was lower than the control group, the difference was statistically significant(P<0.05); Compared with 100μg/ml oxLDL treatment, SOD GSH-PX activity in 100μg/ml oxLDL+CYGB group increased significantly, Bcl2 expression was also increased significantly(P<0.05), LDH and MDA activity was decreased significantly, expression of Bax was significantlylower(P <0.05). Compared with oxLDL treatment, oxLDL+CYGB shRNA group in cell SOD, GSH-PX activity was significantly reduced,Bcl2 expression also reduced(P <0.05), the activity of LDH and MDA significantly increased the expression of Bax increased(P <0.05). 5.Compared with control group, CYGB expression in oxLDL group increased; Compared with oxLDL group, CYGB protein levels in oxLDL+Staurosporine decreased(P<0.05); Compared with oxLDL treatment, cell SOD, GSH-PX in oxLDL+Staurosporine group decreased significantly, Bcl2 expression was significantly lower(P <0.05), the activity of LDH and MDA increased significantly and Bax was increased significantly(P <0.05). [Conclusion] 1. CYGB plays a protective role in endothelial damage induced by oxLDL. 2. The role of CYGB.