Fluoxetine is a selective serotonin reuptake inhibitor that is widely used in the treatment of major depression including after stroke. In this study, we tested whether fluoxetine protects neuronal death in a rat cerebral ischemia model of middle cerebral artery occlusion (MCAO). The administration of fluoxetine intravenously (10 mg/kg) at 30 min, 3 hr, or 6 hr after MCAO reduced infarct volumes to 21.2+/-6.7%, 14.5+/-3.0%, and 22.8+/-2.9%, respectively, of that of the untreated control. Moreover, the neuroprotective effect of fluoxetine was evident when it was administered as late as 9 hr after MCAO/reperfusion. These neuroprotective effects were accompanied by improvement of motor impairment and neurological deficits. The fluoxetine-treated brain was found to show marked repressions of microglia activation, neutrophil infiltration, and proinflammatory marker expressions. Moreover, fluoxetine suppressed NF-kappaB activity dose-dependently in the postischemic brain and also in lipopolysaccharide-treated primary microglia and neutrophil cultures, suggesting that NF-kappaB activity inhibition explains in part its anti-inflammatory effect. These results demonstrate that curative treatment of fluoxetine affords strong protection against delayed cerebral ischemic injury, and that these neuroprotective effects might be associated with its anti-inflammatory effects.

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Excitotoxicity and oxidative stress mediate neuronal death after hypoxic-ischemic brain injury. We examined the possibility that targeting both N-methyl-D-aspartate (NMDA) receptor-mediated excitotoxicity and oxidative stress would result in enhanced neuroprotection against hypoxicischemia. 2-Hydroxy-5-(2,3,5,6-tetrafluoro-4-trifluoromethyl-benzylamino)-benzoic acid (Neu2000) was derived from aspirin and sulfasalazine to prevent both NMDA neurotoxicity and oxidative stress. In cortical cell cultures, Neu2000 was shown to be an uncompetitive NMDA receptor antagonist and completely blocked free radical toxicity at doses as low as 0.3 lmol/L. Neu2000 showed marked neuroprotection in a masked fashion using histology and behavioral testing in two rodent models of focal cerebral ischemia without causing neurotoxic side effects. Neu2000 protected against the effects of middle cerebral artery occlusion, even when delivered 8 h after reperfusion. Single bolus administration of the drug prevented gray and white matter degeneration and spared neurologic function for over 28 days after MACO. Neu2000 may be a novel therapy for combating both NMDA receptor-mediated excitotoxicity and oxidative stress, the two major routes of neuronal death in ischemia, offering profound neuroprotection and an extended therapeutic window.

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Sulfasalazine is widely used to treat inflammatory diseases. Besides anti-inflammatory actions such as blockade of nuclear factor-B and cyclooxygenases, we found that 30 to 1000 M sulfasalazine dose dependently blocked N-methyl-D-aspartate receptor-mediated excitotoxicity without intervening kainate or ␣-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid neurotoxicity. The neuroprotective effects of sulfasalazine were attributable to prevention of Ca 2ϩ influx and accumulation through N-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.Accumulating evidence suggests that inflammatory processes play a role in degeneration of neuronal cells in acute and chronic neurodegenerative diseases. For example, the inducible enzyme cyclooxygenase-2 (COX-2) is up-regulated in ischemic brain areas following focal cerebral ischemia and global forebrain ischemia (Planas et al., 1995;Nakayama et al., 1998), which converts arachidonic acid into the proinflammatory mediators such as prostaglandins. Selective inhibitors and genetic knockout of COX-2 reduce ischemic neuronal death (Sasaki et al., 1988;Iadecola et al., 2001). Increased expression of COX-2 is observed in Alzheimer's disease and traumatized brain and spinal cord and probably contributes to progress of diseases (Oka and Takashima, 1997;Resnick et al., 1998;Dash et al., 2000).The transcription factor nuclear factor-B (NF-B) regulates expression of proinflammatory cytokines such as tumor necrosis factor and interleukins, cell adhesion molecules, and the inducible enzymes such as nitric oxide synthase, COXs, and manganese superoxide dismutase (Baeuerle and Baltimore, 1996;O'Neill and Kaltschmidt, 1997) and modulates degeneration of neurons and non-neuronal cells (Beg and Baltimore, 1996;Scatena et al., 1998). Activation of NF-B is observed in basal forebrain cholinergic neurons of patients with Alzheimer's disease and in vulnerable brain areas after ischemic injury (Boissiere et al., 1997;Clemens et al., 1997;Stephenson et al., 2000). Activation of NF-B mediates Nmethyl-D-aspartate (NMDA) receptor-mediated neuronal death but can protect neurons from oxidative stress and apoptosis (Mattson et al., 1997;Taglialatela et al., 1997;Qin et al., 1998;Won et al., 1999). Acetylsalicylate (aspirin), an inhibitor of COXs and NF-B, holds multiple therapeutic effects, including anti-inflammatory, analgesic, and antipyretic effects (Kopp and Ghosh, 1994;Vane and Botting, 1998). Aspirin reduces platelet aggregation and the risk of recurrent stroke (Diez-Tejedor et al., 1995). Acetyl salicylate also attenuates ischemic neuronal death, cognitive deficiency in Alzheimer's disease, and