bFGF inhibits ER stress induced by ischemic oxidative injury via activation of the PI3K/Akt and ERK1/2 pathways.

Extensive research has focused on finding effective strategies to prevent or improve recovery from brain ischemia and reperfusion (I/R) injury. The basic fibroblast growth factor (bFGF) has been shown to have therapeutic potential in some central nervous system (CNS) disorders, including ischemic injury. In this study, we demonstrate that bFGF administration can improve locomotor activity and inhibit the ER stress induced in the CA1 region of the hippocampus in a mouse model of I/R injury. In vitro, bFGF exerts a protective effect by inhibiting the ER stress response proteins CHOP, XBP-1, ATF-6 and caspase-12 that are induced by H(2)O(2) treatment. Both of these in vivo and in vitro effects are related to the activation of two downstream signaling pathways, PI3K/Akt and ERK1/2. Inhibition of the PI3K/Akt and ERK1/2 pathways by specific inhibitors, LY294002 and U0126, respectively, partially reduce the protective effect of bFGF. Taken together, our results indicate that the neuroprotective role of bFGF involves the suppression of ER stress in the ischemic oxidative damage models and oxidative stress-induced PC12 cell injury, and these effects is underlying the activation of the PI3K/Akt and ERK1/2 signal pathway.