Apoptotic Effect of Lead Acetate on Mice Astrocytes

Objective To study lead acetate induced apoptosis of mice astrocytes C8 and provide theoretical criteria for the damage of lead to blood-brain barrier.Methods Mice astrocytes C8 in logarithmic growth phase were exposed to different concentration of lead acetate(0,5,10,20,and 40μmol/L) for different time periods(6,12,24,and 48 h).Proliferation of cells was detected by MTT.Cell morphology was observed by inverted phase contrast microscope.Spectrophotometer was used to detect the cell damage level,LDH activity and MDA content in cellular supernatant.The expressions of P53,Bax and Bcl-2 were detected by immunohistochemistry.Cell apoptosis rate was detected by PI-Hoechst33342 stain and flow cytometry. Results Under different concentrations of lead acetate with different treatment time periods,the cell growth activities in treated groups reduced significantly compared to the control group(P0.01) showing concentration and time-dependent relationship.Morphological observation of the group treated with lead acetate(5,and 10μmol/L) for 24h showed that cell density lowered,synapses became shorter and thinner and the intercellular junction reduced compared to control group.LDH and MDA contents in supernatant of toxicant groups increased significantly compared to control group(P0.01).The results of immunohistochemistry showed that the expression of P53 and Bax increased,while that of Bcl-2 decreased. PI-Hoechst33342 double staining and flow cytometry demonstrated that cell apoptosis rate of treated groups increased significantly compared to control group.Conclusions Lead acetate is able to inhibit mice astrocytes growth and accelerate the apoptosis by raising the Bax/Bcl-2 rate value,and finally damages the blood-brain barrier.