The Effects Of PLC-γ1 Signaling Pathway On The Apoptosis Of PC12 Cell Induced By H₂O₂

Objective: To explore the effects of phospholipase C- γ1 (PLC- γ1) signaling pathway on the apoptosis of PC12 cell induced by hydrogen peroxide (H2O2). Methods: After pretreatment with U73122, an inhibitor of PLC- γ1, PC12 cell was exposed in H₂O₂. Hoechst/PI double staining was performed to observe the morphological change under light microscope. MTT assay was used to evaluate the cytoactive, and the percentage of apoptotic cells was analyzed by flow cytometry. DNA fragmentation assay was carried out to characterize cell apoptosis. Western blot was also performed to quantitatively explore the involved downstream signal protein expression changes in PLC- γ1 signaling pathway on the apoptosis of PC12 cell induced by H₂O₂.Result: After inhibition of the PLC- Y 1 signaling pathway by U73122, PC12 cell showed obvious apoptotic morphology, the viable cells decreased significantly, and the percentage of apoptotic cells rose to 35.7%. PC12 cell treated with U73122 showed the distinctive pattern of oliginucleosomes resulting from DNA cleavage in apoptotic cells. Following H₂O₂ treatment, there was a decrease only in the protein level of caspase-3. Further decrease also was observed both in bcl-2 and caspase-3 after U73122 using. The decrease of caspase-3 was on a time-dependent manner after using 50μ M H₂O₂, with or without U73122 pretreatment.