Blockage of NOX2MAPKNF-κB Pathway Protects Photoreceptors against Glucose Deprivation-Induced Cell Death

Abstract EN

Acute energy failure is one of the critical factors contributing to the pathogenic mechanisms of retinal ischemia.

Our previous study demonstrated that glucose deprivation can lead to a caspase-dependent cell death of photoreceptors.

The aim of this study was to decipher the upstream signal pathway in glucose deprivation- (GD-) induced cell death.

We mimicked acute energy failure by using glucose deprivation in photoreceptor cells (661W cells).

GD-induced oxidative stress was evaluated by measuring ROS with the DCFH-DA assay and HO-1 expression by Western blot analysis.

The activation of NOX2/MAPK/NF-κB signal was assessed by Western blot and immunohistochemical assays.

The roles of these signals in GD-induced cell death were measured by using their specific inhibitors.

Inhibition of Rac-1 and NOX2 suppressed GD-induced oxidative stress and protected photoreceptors against GD-induced cell death.

NOX2 was an upstream signal in the caspase-dependent cell death cascade, yet the downstream MAPK pathways were activated and blocking MAPK signals rescued 661W cells from GD-induced death.

In addition, GD caused the activation of NF-κB signal and inhibiting NF-κB significantly protected 661W cells.

These observations may provide insights for treating retinal ischemic diseases and protecting retinal neurons from ischemia-induced cell death.