Andrographolide inhibits TNFα-induced ICAM-1 expression via suppression of NADPH oxidase activation and induction of HO-1 and GCLM expression through the PI3K/Akt/Nrf2 and PI3K/Akt/AP-1 pathways in human endothelial cells.

Abstract

Andrographolide, the major bioactive component of Andrographis paniculata, has been demonstrated to have various biological properties including anti-inflammation, antioxidation, and anti-hepatotoxicity. Oxidative stress is considered a major risk factor in aging, inflammation, cancer, atherosclerosis, and diabetes mellitus. NADPH oxidase is a major source of endogenous reactive oxygen species (ROS). In this study, we used EA.hy926 endothelial-like cells to explore the anti-inflammatory activity of andrographolide. Andrographolide attenuated TNFα-induced ROS generation, Src phosphorylation, membrane translocation of the NADPH oxidase subunits p47(phox) and p67(phox), and ICAM-1 gene expression. In the small hairpin RNA interference assay, shp47(phox) abolished TNFα-induced p65 nuclear translocation, ICAM-1 gene expression, and adhesion of HL-60 cells. Andrographolide induced the gene expression of heme oxygenase 1 (HO-1) and glutamate cysteine ligase modifier subunit (GCLM) in a time-dependent manner. Cellular glutathione (GSH) content was increased by andrographolide. shGCLM attenuated the andrographolide-induced increase in GSH content and reversed the andrographolide inhibition of HL-60 adhesion. shHO-1 showed a similar effect on andrographolide inhibition of HL-60 adhesion to shGCLM. The mechanism underlying the up-regulation of HO-1 and GCLM by andrographolide was dependent on the PI3K/Akt pathway, and both the Nrf2 and AP-1 transcriptional factors were involved. Our results suggest that andrographolide attenuates TNFα-induced ICAM-1 expression at least partially through suppression of NADPH oxidase activation and induction of HO-1 and GCLM expression, which is PI3K/Akt pathway-dependent.

• Authors: Chia-Yang Lu, Ya-Chen Yang, Chien-Chun Li, Kai-Li Liu, Chong-Kuei Lii, Haw-Wen Chen
• Journal: Biochemical pharmacology (Biochem Pharmacol) Vol. 91 Issue 1 Pg. 40-50 (Sep 01 2014) ISSN: 1873-2968 [Electronic] England
• PMID: 24998495 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2014. Published by Elsevier Inc.

Chemical References

• Diterpenes
• NF-E2-Related Factor 2
• NFE2L2 protein, human
• Reactive Oxygen Species
• Transcription Factor AP-1
• Tumor Necrosis Factor-alpha
• Intercellular Adhesion Molecule-1
• andrographolide
• HMOX1 protein, human
• Heme Oxygenase-1
• NADPH Oxidases
• Proto-Oncogene Proteins c-akt
• JNK Mitogen-Activated Protein Kinases
• GCLM protein, human
• Glutamate-Cysteine Ligase
• Glutathione

Topics

• Cell Adhesion (drug effects)
• Cells, Cultured
• Diterpenes (pharmacology)
• Endothelial Cells (drug effects, metabolism)
• Gene Expression Regulation (drug effects)
• Glutamate-Cysteine Ligase (genetics, metabolism)
• Glutathione (metabolism)
• HL-60 Cells (drug effects)
• Heme Oxygenase-1 (genetics, metabolism)
• Humans
• Intercellular Adhesion Molecule-1 (metabolism)
• JNK Mitogen-Activated Protein Kinases (metabolism)
• NADPH Oxidases (metabolism)
• NF-E2-Related Factor 2 (metabolism)
• Oxidative Stress (drug effects)
• Phosphatidylinositol 3-Kinases
• Phosphorylation (drug effects)
• Proto-Oncogene Proteins c-akt (metabolism)
• Reactive Oxygen Species (metabolism)
• Signal Transduction (drug effects)
• Transcription Factor AP-1 (metabolism)
• Tumor Necrosis Factor-alpha (metabolism, pharmacology)