Effect of Geranylgeranylacetone on the p-JNK Expression During the Apoptotic Process of Airway Smooth Muscle Cells Induced by Cigarette Smoke Extract

Objective: To study the effect of HSP70 induced by geranylgeranylacetone(GGA) on p-JNK expression in the apoptosis of airway smooth muscle cells(ASMCs) induced by cigarette smoke extract(CSE).Methods: The ASMCs in Wistar rats were cultured in vitro and stimulated with different concentrations of CSE for three hours before and after treated by GGA.The apoptosis was determined by flow cytometry(FCM),and the expression of HSP70 and p-JNK were determined by Western blot.Results: The apoptosis of ASMCs increased in CSE groups and it was associated with the rising CSE concentration(P0.05,n=4);the apoptosis of ASMCs in CSE groups with previously treated by GGA were significantly decreased compared with those of the CSE groups(P0.05).After stimulating by CSE,the expression of HSP70 was lower than that of the control group,and it was associated with the increased CSE concentration(P0.05);the expression of p-JNK was higher than that of control group,and it was also associated with the increased CSE concentration(P0.05).The expression of HSP70 in GGA pretreatment groups was significantly and respectively increased compared with that of the control(all P0.05).The expression of HSP70 was mildly decreased in CSE groups with GGA pretreatment but showed no significant difference,while the expression of p-JNK in CSE groups previously treated by GGA was significantly lower than that of in CSE groups respectively(all P0.05).Conclusion: Higher concentration of CSE may induce the apoptosis of ASMCs and increase the expression of p-JNK.The expression of HSP70 was increased and the apoptosis of ASMCs induced by higher concentration CSE was suppressed after the treatment of GGA,and it suggests that HSP70 could down-regulate the expression of p-JNK during the process.