Cytokine-induced cell death in immortalized Schwann cells: roles of nitric oxide and cyclic AMP
Autor(es): Nagano S,Takeda M,Ma L,Soliven B
Resumo: Tumor necrosis factor-alpha and interferon-gamma are pleiotropic cytokines that regulate Schwann cell responses during injury and inflammatory demyelination. We have previously shown that cyclic AMP (cAMP)-elevating agents decrease the demyelination and Wallerian degeneration in experimental allergic neuritis. In this study, we examined the role of cAMP in cytokine-mediated signaling in a spontaneously immortal Schwann cell clone (iSC). We found that tumor necrosis factor-alpha and interferon-gamma exert synergistic inhibitory action on Schwann cell viability via the production of nitric oxide (NO) and ceramide (cer). Furthermore, we found that: (i) NO synthase inhibitors attenuate the cytokine-induced cer accumulation and cell death indicating that NO acts upstream of cer; and (ii) cytokine-induced cell death is decreased in iSCs pretreated continuously for 48-72 h with forskolin, an activator of adenylate cyclase. Although forskolin modulates the phosphorylation of ERKs and Akt, it decreases the susceptibility of iSC to cytokines via a separate mechanism operating after NO induction and before cer accumulation. We propose that the protective effect of cAMP-elevating agents in experimental allergic neuritis may be mediated in part via modulation of Schwann cell responses to cytokines.
Imprenta: Journal of Neurochemistry, v. 77, n. 6, p. 1486-1495, 2001
Identificador do objeto digital: 10.1001/archneurol.2011.47
Descritores: Guillain-Barre Syndrome - Biosynthesis ; Guillain-Barre Syndrome - Cell ; Guillain-Barre Syndrome - Pathogenesis ; Guillain-Barre Syndrome - Proteins ; Guillain-Barre Syndrome - Cytokines ; Guillain-Barre Syndrome - Immunology
Data de publicação: 2001