Figure 6. p38MAPK pathway is activated and modulates IL-6 secretion in astrocytes.
(A) Western blots depict the levels of total and phosphorylated p38MAPK and heat shock protein 27 (Hsp27) in pre-senescent and H2O2-induced senescent astrocytes with β-actin as loading control. (B) Pre-senescent and senescent astrocytes were treated with 10 µM SB-203580 or DMSO as a control for 48 hours prior to incubation in serum-free MCDB105 media. Conditioned media was collected after 24 hours and IL-6 was analyzed by ELISA (R&D Systems, Inc.; Minneapolis, MN) and normalized to cell number. Graph depicts the relative level of IL-6 (n = 3), *P<0.01 vs. senescent, Student’s t test.