The Study Of Apoptosis Of Lead Induced Mouse Fibroblasts By Interfering Cellular Homeostasis

Agricultural products is the main food with people live that in different processing easy to be contaminated with lead,lead concentration in the food chain tissue and brain have toxicity to human body,can induce cell apoptosis and cause damage to multiple systems.We choose mouse fibroblast establish lead-induced apoptosis model,using cell biology,biochemistry and molecular biology methods from the cells,the cellular and molecular level to explore the apoptosis effect of lead on fibroblasts and its mechanism,for the further study of lead induced fibroblast apoptosis provide scientific,objective experimental data and methods,for the prevention of lead poisoning effect and treatment to provide new ideas and approaches.Lead inducing mouse fibroblast apoptosis model was established,cell toxicity was determined by MTT method,microstructure and submicroscopic structure was analyzed by laser confocal microscope and transmission electron microscopy.The relationship between the apoptotic rate and the concentration and time of lead treatment was determined by flow cytometry.The cell cycle and mitochondrial membrane potential were detected,and the influence of lead on cell proliferation and mitochondria was discussed.To analyze the changes of intracellular calcium ions and to monitor the flow rate of extracellular calcium ions to explore the root causes of calcium homeostasis.The oxidative stress of lead on the cell was investigated by detection of the intracellular reactive oxygen species.RT-PCR was used to detect the expression of apoptosis related genes and analyze the relationship between gene expression regulation and apoptosis.40μM,80μM and 160μM Pb（Ac）₂ have a certain apoptosis effect on the mouse fibroblasts in 12-48h,the cell has typical apoptotic morphological changes,and the apoptosis rate presents the concentration and time dependence.Lead can inhibit cell proliferation in G0/G1 and reduce mitochondrial transmembrane potential.Lead breaks the intracellular calcium homeostasis,and intracellular calcium is releasedfrom endogenous calcium reservoir.Lead can disturb cell oxidation-antioxidant balance,leading to cell oxidative damage.The ratio of gene Bax and bcl-2 expression increased with the increase of lead concentration,and the expression of P⁵³ increased with the increase of lead concentration.Lead had induced apoptosis on mouse fibroblasts,and the apoptotic rate showed concentration and time dependence.Lead induced mouse fibroblast apoptosis by restrain DNA synthesis,reducing mitochondrial membrane potential and damages its function,Break the steady state of calcium,oxidative damage and regulation of gene expression.