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

The overactivity of cannabinoid 1 receptor (CB1R) is associated with obesity and type 2 diabetes. First‐generation CB1R antagonists, such as rimonabant, offered therapeutic advantages for the control of obesity and related metabolic abnormalities, but their therapeutic potential was limited by undesirable neuropsychiatrie side effects. Here, we evaluated AJ5012 as a novel potent peripheral CB1R antagonist and, using this antagonist, investigated the role of peripheral CB1R on adipose tissue inflammation in obese mouse models. AJ5012 had a high degree of CB1R and cannabinoid 2 receptor selectivity but a low brain:plasma concentration ratio without eliciting centrally mediated neurobehavioral effects. In diet‐induced obese (DIO) mice, AJ5012 did not reduce food intake but did induce a significant weight loss, likely owing to an increased energy expenditure. It was as effective as rimonabant for the improvement of hormonal or metabolic abnormalities, glycemic control, and insulin sensitivity. The treatment of DIO and leptin receptor–deficient mice with AJ5012 also exhibited effects comparable to rimonabant for the prevention of macrophage infiltration, activation of the nucleotide‐binding domain and leucine‐rich repeat protein 3 inflammasome, and production of proinflammatory cytokines, which resulted in the suppression of adipose tissue inflammation. In addition to macrophage, activation of CB1R in 3T3‐L1 adipocytes induced the expression of proinflammatory genes, which was fully inhibited by AJ5012. Our findings identified AJ5012 as a novel peripheral CB1R antagonist and suggest that peripheral CB1R blockade might break the links between insulin resistance and adipose tissue inflammation.—Han, J. H., Shin, H., Park, J.‐Y., Rho, J. G., Son, D. H., Kim, K. W., Seong, J. K., Yoon, S.‐H., Kim, W. A novel peripheral cannabinoid 1 receptor antagonist, AJ5012, improves metabolic outcomes and suppresses adipose tissue inflammation in obese mice. FASEB J. 33, 4314–4326 (2019). http://www.fasebj.org

Ethyl pyruvate (EP), a simple aliphatic ester of pyruvic acid, has been shown to act as an anti-inflammatory molecule in various pathological conditions, which include sepsis or hemorrhagic shock. Recently, we showed that ethyl pyruvate has a neuroprotective effect in the postischemic brain and also in KA-induced pathogenesis in the brain. In this study, we examined whether aspirin augments neuroprotective effect of ethyl pyruvate in transient focal ischemia model by complementing the neuroprotective effects of ethyl pyruvate. Although, most of neuroprotective effect of aspirin has been attributed to the anti-platelet action, aspirin also has direct neuroprotective effects, including NF-kappaB inhibition. Ethyl pyruvate dose-dependently suppressed infarct formation in the postischemic brain, wherein intravenous administration of 5 mg/kg ethyl pyruvate 30 min after the occlusion reduced infarct volume to 34.5 +/- 15.5% (n = 6, P < 0.01) of that of the untreated control. In combination with aspirin (5 mg/kg, i.v.), the neuroprotective effect was enhanced, resulting in 16.0 +/- 5.9% (n = 6, P < 0.01) infarct volume. The time window for synergistic neuroprotection by ethyl pyruvate and aspirin extended to 9 h post-MCAO. The synergistic reduction in infarct volume was accompanied by suppression of the clinical manifestations associated with cerebral ischemia including motor impairment and neurological deficits. Inflammatory processes including microglial activation and proinflammatory cytokine expression were notably suppressed by the combination treatment in the postischemic brain and in primary microglia cultures, wherein ethyl pyruvate and aspirin modulate NF-kappaB signaling differentially. Aspirin interferes with IkappaB phosphorylation and degradation in the cytoplasm, possibly by specifically inhibiting IkappaB kinase-beta, whereas, the effect of ethyl pyruvate seems to occur in the nucleus, where it may interfere with the binding of NF-kappaB to responsive promoter elements in the target genes. Similar enhancement in neuroprotective effect was also observed in primary cortical cultures after NMDA or Zn(2+) treatment or oxygen-glucose deprivation. Together, these results indicate that combination treatment of ethyl pyruvate and aspirin affords synergistic neuroprotection in the postischemic brain with a wide therapeutic window, in part via differential modulation of the NF-kappaB signaling pathway.

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