Figure 2.

Cell surface GRP78 mediates HG-induced Akt and FAK activation in response to HG. MCs were treated with HG for 3 h, a time when we previously showed these to be activated upstream of profibrotic effects. FAK and Akt activation were assessed by their phosphorylation on Tyr-397 and Ser-473, respectively. A, MCs were pretreated with antibodies targeting the C (C20, 2 μg/ml) or N terminus (N20, 2 μg/ml) of GRP78 for 1 h. (n = 5). Con, control. B, MCs were pretreated with SubA (25 ng/ml) or an inactive mutant (Mut, 25 ng/ml) for 1 h. (n = 10). C, MTJ-1 was down-regulated using siRNA prior to treatment with HG (n = 3). *, p < 0.05 HG versus control; ‡, p < 0.05 versus HG.