Fig. 4

Rottlerin attenuates upregulation of MMP-9 by PMA through blocking the Nox/ROS-mediated ERK1/2 activation in RBA cells. a Cells were pretreated with PD98059 (10 μM) and then incubated with PMA (1 μM) for the indicated time intervals. b Cells were treated with PMA (1 μM) for the indicated times. c, d Cells were pretreated with NAC (5 mM), Apo (10 μM), PD98059 (PD, 10 μM), and Rott (1 μM) for 1 h and then stimulation with PMA (1 μM) for the indicated times. The conditioned media were collected and assayed for MMP-9 expression by gelatin zymography (a). The cell lysates were collected and analyzed phosphorylation of ERK1/2 (p-ERK1/2), total ERK2, and GAPDH by Western blot (b–d) as described in the “Methods” section. Data are expressed as the mean ± SEM (N = 3). ^#P < 0.01, as compared with the respective values of untreated control. *P < 0.05; **P < 0.01, as compared with the respective values of untreated cells (a) or cells stimulated with PMA only (b). The image represents one of three individual experiments