Polypeptide Fraction from Arca subcrenata Induces Apoptosis and G2/M Phase Arrest in HeLa Cells via ROS-Mediated MAPKs Pathways

Figure 6

ROS played a critical role in P2-inhibited growth, -induced apoptosis, and -modulated effect on MAPKs pathways of HeLa cells. (a) NAC significantly attenuated the inhibitory effect of P2 on HeLa cells. Cells were treated with 5 mM of NAC for 1 h before treatment with 1.5, 3, 6, 12, 24, and 48 μg/mL of P2 for 48 h. Cells inhibitory rate was assessed by MTT assay. Compared with P2 single treatment, , (). (b) NAC abrogated the apoptosis-inducing effect of P2 on HeLa cells. Cells were treated with 5 mM of NAC for 1 h before treatment with 12 μg/mL of P2 for 48 h. The rate of apoptosis was detected by FCM. (c) NAC markedly reversed the expression of apoptosis-related proteins including caspase-9 and PARP. Cells were treated with 5 mM of NAC for 1 h before treatment with 12 μg/mL of P2 for 48 h and the expression of caspase-9 and PARP was determined by western blot assay with GAPDH as an internal control. Results shown are the representation of three independent experiments. (d) NAC attenuated the modulated effect of P2 on MAPKs pathways in HeLa cells. Cells were treated with 5 mM of NAC for 1 h before treatment with 12 μg/mL of P2 for 48 h. The expression of ERK1/2, JNK1/2, p38 MAPK, p-ERK1/2, p-JNK1/2, and p-p38 MAPK was detected by western blot assay with GAPDH as an internal control. Results shown are the representation of three independent experiments.

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