Regulation of inflammatory response in neural cells in vitro by thiadiazolidinones derivatives through peroxisome proliferator-activated receptor γ activation

Abstract

In most neurodegenerative disorders, including multiple sclerosis, Parkinson disease, and Alzheimer disease, a massive neuronal cell death occurs as a consequence of an uncontrolled inflammatory response, where activated astrocytes and microglia and their cytotoxic agents play a crucial pathological role. Current treatments for these diseases are not effective. In the present study we investigate the effect of thiadiazolidinone derivatives, which have been recently suggested to play a role in neurodegenerative disorders. We have found that thiadiazolidinones are potent neuroprotector compounds. Thiadiazolidinones inhibited inflammatory activation of cultured brain astrocytes and microglia by diminishing lipopolysaccharide-induced interleukin 6, tumor necrosis factor a, inducible nitric-oxide synthase, and inducible cyclooxygenase type 2 expression. In addition, thiadiazolidinones inhibited tumor necrosis factor-α and nitric oxide production and, concomitantly, protected cortical neurons from cell death induced by the cell-free supernatant from activated microglia. The neuroprotective effects of thiadiazolidinones are completely inhibited by the peroxisome proliferator-activated receptor γ antagonist GW9662. In contrast the glycogen synthase kinase 3β inhibitor LiC1 did not show any effect. These findings suggest that thiadiazolidinones potently attenuate lipopolysaccharide-induced neuroinflammation and reduces neuronal death by a mechanism dependent of peroxisome proliferator-activated receptor γ activation. © 2005 by The American Society for Biochemistry and Molecular Biology, Inc.