MAPK8 and atrial fibrillation: To further evaluate the role of the MAPK pathway in senescence, AF cell cultures were incubated with a p38 MAPK inhibitor (SB202190; Beyotime, Shanghai, China), an ERK1/2 inhibitor (FR180204; Beyotime, Shanghai, China), a JNK inhibitor (SP600125; Beyotime, Shanghai, China) respectively, before AOPPs treatment.