Nitric Oxide Negatively Regulates c-Jun N-terminal Kinase/Stress-Activated Protein Kinase via S-Nitrosylation

다국어 초록 (Multilingual Abstract)

Nitric oxide(NO), produced from L-arginine in a reaction catalyzed by NO synthase, is an endogenous free radical with multiple functions in mammalian cells. Here we demonstrate that endogenously produced NO can suppress c-Jun N-terminal kinase(JNK) activation in intact cells. Treatment of BV-2 murine microglial cells with interferon-γ induced endogenous NO production concomitantly suppressing JNK1 activation. Similarly, interferon-γ induced suppression of JNK1 activation in RAW264.7 murine macrophage cells and rat alveolar macrophages. The interferon-γ-induced suppression of JNK1 activation in BV-2, RAW264.7, or rat alveolar macrophage cells was completely prevented by N^(G)-nitro-L-arginine, a NO synthase inhibitor. Interestingly, the interferon-γ-induced suppression of JNK1 activation was not affected by 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, an inhibitor of guanylyl cyclase. 8-Bromo-cyclic GMP, a membrane permeable analogue of cyclic GMP, did not change JNK1 activation in intact cells, either. In contrast, S-nitro-N-acetyl-DL-penicillamine(SNAP), a NO donor, inhibited JNK1 activity in vitro. Furthermore, a thiol-reducing agent, dithiothreitol, reversed not only the in vitro inhibition of JNK1 activity by SNAP but also the in vivo suppression of JNK1 activity by interferon-γ. Substitution of serine for cysteine-116 in JNK1 abolished the inhibitory effect of interferon-γ or SNAP on JNK1 activity in vivo or in vitro, respectively. Moreover, interferon-γ enhanced endogenous S-nitrosylation of JNK1 in RAW264.7 cells. Collectively, our data suggest that endogenous NO mediates the interferon-γ-induced suppression of JNK1 activation in macrophage cells via a thiol-redox mechanism.