| First Author | Wegiel B | Year | 2011 |
| Journal | Proc Natl Acad Sci U S A | Volume | 108 |
| Issue | 46 | Pages | 18849-54 |
| PubMed ID | 22042868 | Mgi Jnum | J:180223 |
| Mgi Id | MGI:5305874 | Doi | 10.1073/pnas.1108571108 |
| Citation | Wegiel B, et al. (2011) Biliverdin inhibits Toll-like receptor-4 (TLR4) expression through nitric oxide-dependent nuclear translocation of biliverdin reductase. Proc Natl Acad Sci U S A 108(46):18849-54 |
| abstractText | The cellular response to an inflammatory stressor requires a proinflammatory cellular activation followed by a controlled resolution of the response to restore homeostasis. We hypothesized that biliverdin reductase (BVR) by binding biliverdin (BV) quells the cellular response to endotoxin-induced inflammation through phosphorylation of endothelial nitric oxide synthase (eNOS). The generated NO, in turn, nitrosylates BVR, leading to nuclear translocation where BVR binds to the Toll-like receptor-4 (TLR4) promoter at the Ap-1 sites to block transcription. We show in macrophages that BV-induced eNOS phosphorylation (Ser-1177) and NO production are mediated in part by Ca(2+)/calmodulin-dependent kinase kinase. Furthermore, we show that BVR is S-nitrosylated on one of three cysteines and that this posttranslational modification is required for BVR-mediated signaling. BV-induced nuclear translocation of BVR and inhibition of TLR4 expression is lost in macrophages derived from Enos(-/-) mice. In vivo in mice, BV provides protection from acute liver damage and is dependent on the availability of NO. Collectively, we elucidate a mechanism for BVR in regulating the inflammatory response to endotoxin that requires eNOS-derived NO and TLR4 signaling in macrophages. |
