Objective:To investigate the inhibitory effects of apigenin on interleukin 6 (IL-6)-induced delay in neutrophil apoptosis and its underlying mechanisms.Methods:Neutrophils(Neu) isolated from healthy volunteers were randomly divided into the control group,apigenin group,IL-6 group,IL-6+apigenin group,QVD+IL-6+apigenin group,and z-VAD+IL-6+apigenin group.Neu apoptosis was detected by flow cytometry.The protein expression of cleaved caspase-3 was determined by Western blotting analysis.Results:Compared with the control group,apigenin significantly induced Neu apoptosis (P<0.05),and IL-6 significantly inhibited Neu apoptosis (P<0.05).Apigenin partially reversed the anti-apoptotic effect of IL-6 on Neu (P<0.05).Compared with the IL-6 group,cleaved caspase-3 expression was significantly increased in the IL-6+apigenin group.Moreover,caspase inhibitors QVD-Oph and z-VAD reduced the levels of cleaved caspase-3 and abolished the ability of apigenin to counteract IL-6-induced delay in Neu apoptosis.Conclusion:Apigenin overrides IL-6-induced delayed apoptosis of Neu in a caspase-dependent manner,which provides a promising target for future therapy of neutrophilic inflammatory airway disorders.