| First Author | Boaru SG | Year | 2015 |
| Journal | Biochem Biophys Res Commun | Volume | 458 |
| Issue | 3 | Pages | 700-6 |
| PubMed ID | 25686493 | Mgi Jnum | J:220480 |
| Mgi Id | MGI:5634857 | Doi | 10.1016/j.bbrc.2015.02.029 |
| Citation | Boaru SG, et al. (2015) NLRP3 inflammasome expression is driven by NF-kappaB in cultured hepatocytes. Biochem Biophys Res Commun 458(3):700-6 |
| abstractText | The inflammasomes are cytoplasmic multiprotein complexes that are responsible for activation of inflammatory reactions. In principle, there are four individual inflammasome branches (NLRP1, NLRP3, NLRC4/NALP4, and AIM2) that mediate the cleavage and activation of Caspase-1 and IL-1beta that in turn lead to a complex network of cellular reactions initiating local and systemic inflammatory reactions. We have recently shown that NLRP3 expression is virtually absent in primary cultured hepatocytes and that in vitro the stimulation of hepatocytes with lipopolysaccharides results in strong activation of NLRP3 expression. We here demonstrate that this activation can be blocked by the NF-kappaB activation inhibitor QNZ or by infection with an adenoviral expression vector constitutively expressing a superrepressor of NF-kappaB. We show that QNZ blocks NF-kappaB-dependent expression of TNF-alpha, IL-1beta and NLRP3. Likewise, the superrepressor of NF-kappaB prevents expression of NLRP3 and significantly reduces expression of inflammatory marker genes in liver cells. In a primary murine hepatoma cells, the concomitant depletion of NEMO and Caspase-8 resulted in a significant suppression of NLRP3 expression after Lipopolysaccharide challenge. Moreover, we demonstrate that a 1.3-kbp fragment located in close proximity of the most upstream transcriptional start site of the human NLRP3 gene that harbours one putative octamer NF-kappaB binding site renders LPS sensitivity in reporter gene assay. We conclude that NF-kappaB signalling is a necessary prerequisite for proper activation of the NLRP3 inflammasome in primary hepatocytes. |
