Proliferation Of Retinal Microvascular Cells Research Articles

Quantitative proteomic analysis of human retinal microvascular endothelial cells stimulated with 4-Hydroxynonenal

Objective To detect the protein expression change in the proliferation of human retinal microvascular endothelial cells (hRMECs) stimulated with 4-Hydroxynonenal (4-HNE). Methods hRMECs were in a logarithmic growth phase, and then were separated into 4-HNE-stimulated group and negative control group. The concentration of 4-HNE included 5, 10, 20 and 50 μmol/L in 4-HNE-stimulated group, while the negative control group was added in the same volume of ethanol (the solvent of 4-HNE). Then the cells were stimulated with 4-HNE for 24 hours following by CCK-8 kits incubating for 4 hours to detect absorbance. It was found that 10 μmol/L 4-HNE had the most obvious effect on the proliferation of hRMECs. Therefore, the cellular proteins from 10 μmol/L 4-HNE-stimulated group and negative control group were acquired and prepared by FASP sample preparation method. Data independent acquisition was used for data acquisition, and the GO analysis and pathway enrichment were performed for analysis of differentially expressed proteins. Results CCK-8 kits detection results showed that the A value of the 10 and 20 μmol/L 4-HNE-stimulated groups were significantly higher than negative control group and 5 μmol/L 4-HNE-stimulated group (F=25.42, P 1.5, P<0.05). Seventy-two proteins were up-regulated after 4-HNE stimulation, whereas 46 proteins were down-regulated. Particularly, the expressions of Heme oxygenase-1, Sulfoxdoxin-1, Heat shock protein A1B, Thioredoxin reductase-1, Glutathione reductase, ATPase and prothrombin were increased when cells were added in 4-HNE, whereas the expressions of apolipoprotein A1 and programmed cell death protein 4 were decreased. These differentially expressed proteins were mainly involved in the biological processes such as oxidative stress, cell detoxification, and ATPase-coupled membrane transport. Conclusion After stimulated with 4-HNE, the oxidative stress, cell detoxification, and ATPase-coupled membrane transport protein expression may change in hRMECs in order to regulate oxidative stress and growth situation. Key words: Reitinal vessels/cytology; Endothelial; Cell cultured; Proteomics; 4- Hydroxynonenal

Inhibition and mechanism of 15 (S)-hydroxyeicosate traenoic acid on proliferation of hypoxic retinal microvascular endothelial cells in vitro

Background Retninal neovascular diseases caused by hypoxia has become a major blinding disease,which is lack of effective chemical treatment currently,it's important to study the molecuar mechanism of the disease,so as to guide the clinical medication.Objective This study was to explore the effect of 15 (S)-hydroxyeicosate traenoic acid (15-HETE) on the proliferation of hypoxic retinal microvascular endothelial cells (RMVECs) and its probable mechanism.Methods RMVECs were isolated from C57BL/6J mice and incubated and then identified with anti-Ⅷ factor antibody by immunochemistry and immunofluorescence.The cells were divided into the normoxia group and the hypoxia group.The hypoxia cell models were established by treated with 125 μmol/L CoCl2.The cells were cultured with serum-free DMEM containing endothelial cell growth supplement (ECGS)and high glucose for 48 hours,and then different concentrations of 15-HETE (0.0,0.1,1.0,5.0 μmol/L) were added in the medium for 48 hours respectively to subgroup the groups.The proliferation of the cells (absorbance,A) was detected using MTT.The relative expression levels of protein and mRNA of hypoxia inducible factor-1α (HIF-1α),bcl-2 and caspase-3 were assayed by reverse transcription PCR (RT-RCR)and Western blot.Results The cells showed the positive response for anti-Ⅷ factor antibody with the positive rate of (94.38 ±4.25)％.No significant difference was found in the cell proliferation of various groups under the normoxia condition (F =0.283,P =0.837),but under the hypoxia condition,the proliferation values were significantly different among various groups (F =702.582,P＜0.001).The cell proliferation value in the 1.0 μmol/L 15-HETE group and 5.0 μmol/L 15-HETE group was lower than that of the simple hypoxia group respectively(both at P＜0.05).The inhibitory rates in the 0.1,1.0,5.0 μ mol/L 15-HETE groups were (1.09±0.31) ％,(21.09± 3.53) ％ and (49.86 ±4.15) ％,showing a dosedependent manner.No significant difference was seen in the expression levels of bcl-2,caspase-3 and HIF-1α mRNA in various groups under the normoxia conditions.However,compared with the simple normoxia group,the relative expressions of bcl-2 mRNA and HIF-1α mRNA in the cells were increased by 1.53 folds and 1.7 folds in the simple hypoxia group respectively,and caspasse-3 mRNA expression decreased by 70％ (all at P ＜ 0.05).Under the normoxia condition,the expression of bcl-2 and pro-caspase-3 protein in the cells were not significantly different among the various groups (P＞0.05),however,the expressions of bcl-2 and pro-caspase-3 proteins were elevated by 1.6 folds and 1.9 folds in the hypoxia group in compared with the normoxia group (P＜0.05).Compared with the simple hypoxia group,the expressions of bcl-2 and pro-caspase-3 were lowed by 40.4％ and 42.5％ in the 5.0 μmol/L 15-HETE group (P＜0.05).Conclusions 15-HETE inhibits the proliferation of RMVECs and therefore suppresses neovascularization by down-regulating the expressions of HIF-1α and bcl-2 and the activation of caspase-3 in a dose-dependent manner. Key words: Retinal neovascularization; Retinal microvascular endothelial cell; Hypoxia inducible factor1α ; Bcl-2; Caspase-3

Effect of varying oxygen concentrations on the proliferation of retinal microvascular cells in vitro

Microvascular fragments and pure cultures of either retinal microvascular endothelial cells, retinal pericytes or Tenon's capsule fibroblasts were grown on a gas permeable substrate while exposed to varying oxygen concentrations (5, 10, 20, 40 and 95% oxygen). For all three cell types cell proliferation was greatest under the lowest oxygen concentration and decreased as the oxygen concentration increased. The decrease in the proliferative ability of cells exposed to the higher oxygen concentrations could be reversed if the cells were returned to a normoxic environment. Endothelial cells were the most sensitive to changes in oxygen tensions showing a proliferative response after 24 hr exposure as opposed to 48 hr for pericytes and fibroblasts. These results suggest a direct mechanism by which the intra-vitreal and intra-retinal oxygen tension may influence both the development of preretinal new vessels (in response to retinal ischaemia) and also the regression of neovascularization following scatter photocoagulation or vitrectomy.