The molecular mechanism of apoptosis of human umbilical vein endothelial cells induced by monocyte chemotacitic protein-1 / 生理学报

The present study was aimed to investigate whether Bcl-2, Fas and Bax are involved in monocyte chemotacitic protein-1 (MCP-1)-induced apoptosis of human umbilical vein endothelial cells (hUVECs). hUVECs were cultured, and the purity was identified by immunofluorescence and immunohistochemistry with specific anti-von Willebrand factor (vWF) and anti-VEGF receptor-2 (KDR) antibodies. With 90% confluence hUVECs were serum-starved for 12 h, and then treated with different concentrations of MCP-1 (0.1, 1.0, 10, 100 ng/mL) for 24 and 48 h respectively. The expressions of apoptosis related proteins Fas, Bcl-2, Bax were detected by flow cytometry (FACS) and Western blot. As shown in our preliminary study, MCP-1 induced apoptosis of hUVECs in a dose-dependent manner at both 24 h and 48 h. FACS and Western blot analysis results in the present study indicated that MCP-1 promoted the expression of proapoptotic proteins Bax and Fas and inhibited the expression of antiapoptotic protein Bcl-2. These results suggest that MCP-1 may induce the apoptosis of hUVECs through evoking the imbalance between proapoptotic Fas/Bax and antiapoptotic Bcl-2 protein.

Co-treatment with ethanol enhances the toxicity of 6-hydroxydopamine.

6-Hydroxydopamine (6-OHDA) is a widely used neural toxin in the pathogenesis research of Parkinson's disease (PD). In this work, we have studied the effect of ethanol on the toxicity of 6-OHDA on PC12 cell and SK-N-SH cell. Ethanol alone had little toxicity to these cells. However, if using 40 microM 6-OHDA along with 400 mM ethanol on PC12 cell or SK-N-SH cell for 24h, there was much more cell loss than using 40 microM 6-OHDA alone when detected by 3-(4,5-dimethylthiazal-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay or flow cytometric assay. The toxicity of 6-OHDA was enhanced only if using at least 200 mM ethanol, and the cell loss was increased with the increase of ethanol concentration. We had also found that ethanol could enhance the toxicity of 6-OHDA only when using ethanol and 6-OHDA at the same time, ethanol treatment either before or after 6-OHDA treatment did not show such effect. This effect of ethanol suggests that ethanol may contribute to the degeneration of dopaminergic cells.