Figure 2. TAK1 inactivation was required for TNFα-induced p-eNOS expression.

(A) HUVECs were treated by TNFα (20 ng/ml) in a time-dependent manner, and the phosphorylation level of TAK1 was detected by Western blotting. (B) TAK1 phosphorylation in HUVECs after stimulation with TNFα for 2 hrs with or without AdsiA20 pre-treatment. (C) The effect of A20 on TNFα-induced p-eNOS expression with or without AdsiTAK1 (scramble siRNA as negative control). (D) The effect of A20 on TNFα-induced HUVECs apoptosis with or without AdsiTAK1 (scramble siRNA as negative control) measured by TUNEL staining. (E) Relative quantification of NO release using nitrate reductase method in HUVECs treated by different conditions. *P<0.05 versus control group, respectively (n=6 independent experiments).