These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: Involvement of different nuclear hormone receptors in butyrate-mediated inhibition of inducible NF kappa B signalling. Author: Schwab M, Reynders V, Loitsch S, Steinhilber D, Stein J, Schröder O. Journal: Mol Immunol; 2007 Jul; 44(15):3625-32. PubMed ID: 17521736. Abstract: BACKGROUND: NF kappa B plays a major role in the control of immune responses and inflammation. Recently, butyrate has not only been demonstrated to suppress NF kappa B activation in colorectal cancer cells, but also to modulate the activity and expression of the Peroxisome-Proliferator-Activated-Receptor gamma (PPAR gamma) and the vitamin D receptor (VDR). Therefore, we investigated a putative involvement of both receptors in butyrate-mediated inhibition of inducible NF kappa B signalling. RESULTS: Treatment of HT-29 cells with butyrate attenuated basal p50 as well as TNFalpha- and LPS-induced p50 and p65 NF kappa B dimer activity in the nucleus as measured by transcription factor assay. Cytosolic expression of I kappa B alpha protein was reduced by butyrate, and TNFalpha but not by LPS. Challenge of cells with the VDR antagonist ZK191732 up-regulated basal NF kappa B activity by decreasing I kappa B alpha simultaneously, while basal signalling was not influenced by the PPAR gamma inhibitor GW9662. Pre-treatment with ZK191732 reduced the inhibitory effect of butyrate on NF kappa B activation caused by TNFalpha whereas no activation was noted in transfected dominant-negative PPAR gamma mutant vector cells. Adversely, the inhibitory effect of butyrate on NF kappa B activity induced by LPS was almost reversed in dominant-negative PPAR gamma mutant cells while pre-incubation of ZK191732 did not affect butyrate-mediated attenuation of LPS-induced NF kappa B signalling. CONCLUSION: These findings provide evidence for the involvement of the nuclear hormone receptors PPAR gamma and VDR in butyrate-mediated inhibition of inducible NF kappa B activation dependent on the stimulated signalling pathway. Moreover, VDR appears to play an inhibitory role in the regulation of basal NF kappa B signalling.[Abstract] [Full Text] [Related] [New Search]