The novel neuroprotective action of sulfasalazine through blockade of NMDA receptors

Sulfasalazine is widely used to treat inflammatory diseases. Besides anti-inflammatory actions such as blockade of nuclear factor-κB and cyclooxygenases, we found that 30 to 1000 μM sulfasalazine dose dependently blocked N-methyl-D-aspartate receptor-mediated excitotoxicity without intervening kainate or α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid neurotoxicity. The neuroprotective effects of sulfasalazine were attributable to prevention of Ca²⁺ influx and accumulation through N-methyI methyl-D-aspartate receptors as a low-affinity antagonist. The systemic administration of sulfasalazine reduced neuronal death following transient cerebral and retinal ischemia in adult rat. The present findings suggest that the neuroprotective action of sulfasalazine can be therapeutically applied to halt devastating neuronal death following hypoxic ischemia, trauma, and neurodegenerative diseases.