The Changes Of Endothelial Cell's Function And Its Mechanism During Growing And Senescent Process

Objective To investigate the changes of endothelial cell's morphology and cell cycle during growing and senescent process.Method Human umbilical vein endothelial cells (HUVECs) were cultured in vitro. Aging models of HUVECs were established through cell passage or being stimulated by TNF-α. The morphology of passage cells were surveyed by light microscope and electron transmission microscope. The second, fourth, sixth and eighth filial generational endothelial cells were selected to detect their cell cycle.Result The cellular structure presented degenerate through cell passage. In the younger, endothelial cells grew faster. Observed by light microscope, the endochylema was transparent and the outline of nuclear was clear. The shape of endothelial cells were regular observed by electron microscope. The peripheria of nuclear was round or orbicular-ovate. There were a large number of mitochondria and endoplasmic reticulum in endochylema. The collocation of cells were rarefaction and their size became ununiformity comparing with the younger. Under electron microscope the volume of endothelial cells became smaller. The number of mitochondria and endoplasmic reticulum is less than before. Flow cytometry detection of DNA by using propidium iodide labeling showed the number of G2/M phase cell is more in low passage cell. More cells stagnated inG0/G1 phase in high passage cells. At the same time cell proliferation index decreased following generation.Conclusion The morphology of aging cells had marked change. Their organelle became less and their cytoactive decreased step by step. The ability to resist the harm also decreased. Objective To study the expression of Monocyte Chemoattractant Protein-1mRNA in endothelial cells during Growing and Senescent process.Method Human umbilical vein endothelial cells were cultured in vitro. The second, forth, sixth and eighth filial generational endothelial cells were selected to extract total RNA by trizol. Determine and evaluate the expression of Monocyte Chemoattractant Protein-1mRNA in different passage cells by two-step RT-PCR method.Result The expression of MCP-1 mRNA was upregulated rapidly following generation, reaching top at the sixth filial generation and decreased subsequently. The expression of MCP-1 mRNA had significant difference among different groups(p<0.05). The same tendency was observed in the cells stimulated by TNF-ɑ, but showed more intense expression of MCP-1 mRNA.Conclusion The expression of Monocyte Chemoattractant Protein-1mRNA in endothelial cells increased during Growing process, reaching top at the sixth filial generation and decreased subsequently. Objective To explore the relationship between mitochondrial membrane potential and reactive oxygen species of endothelial cell during growing and senescent process.Method Human umbilical vein endothelial cells were cultured in vitro. The second, fourth, sixth and eighth filial generational endothelial cell were selected to detect the magnitude of mitochondrial membrane potential and reactive oxygen species by Flow Cytometry.Result The fluorescent intensity in high-passage cells increased obviously; whereas the reactive oxygen species decreased obviously. And mitochondrial membrane potential decreased in the older. There were significant difference among different generation(P<0.05). The same change appeared in the endothelial cells stimulated by TNF-α.Conclusion Along with degenerate, the mitochondrial membrane potential decreased while reactive oxygen species increased, which implicated the function of mitochondrial decreased and lipid oxidation increased in aged cells.