Figure 5. Regulation of senescence-associated hyper-activation via p38-MAPK (p38) pathway. (A, B) IR HUVEC exhibit higher activation of p38 than NC HUVEC. Representative western-blot images (A) and densitometry based quantitative analysis (B) of phosphorylated p38 (p-p38) and total p38 (p38) in NC HUVEC and IR HUVEC stimulated with LPS (30 ng/ml) for 0-6 hours. (n = 3; mean ± SEM; * p<0.05, # p <0.01, + p<0.001 vs. NC HUVEC). β-actin was used as a loading control. (C–F) p38 inhibition attenuates the expression of IL6 (C), TNFα (D), CCL5 (E), and IL1β (F) mRNA in IR-HUVEC. NC HUVEC and IR-HUVEC were exposed to LPS (30 ng/ml) or the p38 inhibitor losmapimod (1 μM) or their combination for 3 hours followed by mRNA analysis. Gene expression in unstimulated NC HUVEC was used as baseline and GAPDH was used as endogenous control (n = 3; mean ± SEM; * p<0.05, ** p<0.01, *** p<0.001).