FIG. 4.

Alpha-lipoic acid inhibits TNF- and IL1B-induced MMP9 activities in amnion epithelial cells. a) Representative zymogram of TNF-induced (A) and IL1B-induced (B) MMP9 activities and inhibition by pretreatment with LA in amnion epithelial cells treated as in Figure 3. b) Densitometric analysis of zymograms detecting MMP9 activities from three experiments using epithelial cell isolates from the amnions of three different patients (n = 3). Tumor necrosis factor-induced (A and B) or IL1B-induced (C and D) MMP9 enzyme activities by amnion epithelial cells. Pretreatment with increasing doses of LA inhibited these cytokine-induced increases. Data are presented as mean ± SD. Columns with symbols indicate data are significantly different; P < 0.001 (*, due to cytokine dose; triangle, due to inhibition of the cytokine-induced effect by LA). KD and kd, kilodalton.