title: Isoliquiritigenin inhibits IkappaB kinase activity and ROS generation to block TNF-alpha induced expression of cell adhesion molecules on human endothelial cells.
abstract: Isoliquiritigenin (ILTG) is a flavonoid with chalcone structure (4,2',4'-trihydroxychalcone), an active component present in plants like Glycyrrhiza and Dalbergia which showed various biological activities including anti-inflammatory, anti-carcinogenic and antihistamic. As very little is known in regard to the underlying mechanism involved in explaining the various activities of the compound, we carried out a detailed study on the effect of ILTG on the expression of cell adhesion molecules on human primary endothelial cells. We demonstrate here that ILTG inhibits TNF-alpha induced adhesion of neutrophils to endothelial monolayer by blocking the expression of ICAM-1, VCAM-1 and E-selectin. Since NF-kappaB is a major transcription factor involved in the transcriptional regulation of cell adhesion molecules, thus we studied the status of NF-kappaB activation in ILTG treated endothelial cells. We demonstrate that ILTG inhibits the translocation and activation of nuclear factor-kappaB (NF-kappaB) by blocking the phosphorylation and subsequent degradation of IkappaBalpha. As oxidative stress is also known to regulate the activation of NF-kappaB to modulate TNF-alpha signaling cascade, we tested the effect of ILTG on reactive oxygen species (ROS). We found that it inhibits TNF-alpha induced ROS production in endothelial cells. These results have important implications for using ILTG or its derivatives towards the development of effective anti-inflammatory molecules.
authors.affiliation: Molecular Immunogenetics Laboratory, Institute of Genomics and Integrative Biology, University of Delhi Campus (North), Mall Road, Delhi, India.
authors.forename: Sarvesh
authors.initials: S
authors.lastname: Kumar
authors.forename: Amit
authors.initials: A
authors.lastname: Sharma
authors.forename: Babita
authors.initials: B
authors.lastname: Madan
authors.forename: Vandana
authors.initials: V
authors.lastname: Singhal
authors.forename: Balaram
authors.initials: B
authors.lastname: Ghosh
mesh_terms: D015815:Cell Adhesion Molecules / Q000235:genetics / Q000378:metabolism*; D047188:Chalcones / Q000494:pharmacology*; D019040:E-Selectin / Q000378:metabolism; D042783:Endothelial Cells; D004730:Endothelium, Vascular / Q000187:drug effects* / Q000378:metabolism; D015870:Gene Expression / Q000187:drug effects / Q000502:physiology; D006801:Humans; D051550:I-kappa B Kinase / Q000378:metabolism; D020672:I-kappa B Proteins / Q000378:metabolism; D018799:Intercellular Adhesion Molecule-1 / Q000378:metabolism; D000072000:NF-KappaB Inhibitor alpha; D016328:NF-kappa B / Q000378:metabolism; D009504:Neutrophils / Q000187:drug effects / Q000378:metabolism; D050811:Octamer Transcription Factor-1 / Q000378:metabolism; D010766:Phosphorylation / Q000187:drug effects; D017382:Reactive Oxygen Species / Q000378:metabolism*; D018808:Transcription Factor AP-1 / Q000378:metabolism; D014158:Transcription, Genetic / Q000187:drug effects* / Q000502:physiology; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism; D019010:Vascular Cell Adhesion Molecule-1 / Q000378:metabolism
chemical_list: D015815:Cell Adhesion Molecules; D047188:Chalcones; D019040:E-Selectin; D020672:I-kappa B Proteins; D016328:NF-kappa B; C000606204:NFKBIA protein, human; D050811:Octamer Transcription Factor-1; D017382:Reactive Oxygen Species; D018808:Transcription Factor AP-1; D014409:Tumor Necrosis Factor-alpha; D019010:Vascular Cell Adhesion Molecule-1; D018799:Intercellular Adhesion Molecule-1; D000072000:NF-KappaB Inhibitor alpha; C040920:isoliquiritigenin; D051550:I-kappa B Kinase