title: Blockade of monocyte-endothelial trafficking by transduced Tat-superoxide dismutase protein.
abstract: It has previously been suggested that reactive oxygen species (ROS) are involved in the pathogenesis of chronic inflammatory diseases, which entails the initial activation of pro-inflammatory cytokines to facilitate leukocyte transmigration. The present study investigated whether intracellular superoxide dismutase (SOD) suppressed monocyte endothelial trafficking and transmigration. Human umbilical vein endothelial cells (HUVECs) and THP-1 monocytes were activated by the cytokine tumor necrosis factor-α (TNF-α) in the absence and presence of cell-permeable transactivator of transcription (Tat)-SOD protein. External stimulation with SOD was conducted using endothelial cells and monocytes. Purified cell-permeable Tat-SOD, but not non-targeted SOD, at 1-3 µM was transduced into endothelial cells in a time‑ and dose-dependent manner. Non-toxic Tat-SOD at ≤0.5 µM, but not 1 µM SOD, blocked the monocyte-endothelium interactions by inhibiting the TNF-α-induced stimulation of vascular cell adhesion molecule-1 (VCAM-1) in HUVECs and integrin β1 in THP-1 cells. Endothelial VCAM-1 induction by TNF-α was responsible for superoxide anion production being quenched by N-acetyl-cysteine and Tat-SOD. SOD treatment markedly inhibited superoxide anion production induced by TNF-α, but no inhibition of endothelial transmigration was noted. Tat-SOD prevented transendothelial monocyte migration by firmly localizing occludin-1, platelet/endothelial cell adhesion molecule‑1 (PECAM-1) and vascular endothelial‑cadherin present in paracellular junctions and inhibiting endothelial induction and activation of matrix-degrading membrane type-1 (MT-1) matrix metalloproteinase (MMP), MMP-2 and MMP-9. By contrast, treatment with 1 µM SOD did not have such effects. Furthermore, transduced Tat-SOD hindered nuclear transactivation of nuclear factor-κB (NF-κB), modulating the induction of paracellular junction proteins and matrix‑degrading MMP in TNF-α‑stimulated HUVECs. Transduced Tat-SOD, but not external SOD, impeded cytokine-induced endothelial adhesion and the transmigration of monocytes. Thus, we suggest that transduced Tat-SOD qualifies as an atheroprotective agent against oxidation-driven and inflammation-associated atherosclerosis.
authors.affiliation: Department of Food Science and Nutrition, Hallym University, Chuncheon, Gangwon 200-702, Republic of Korea.
authors.forename: Sin-Hye
authors.initials: SH
authors.lastname: Park
authors.affiliation: Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, Gangwon 200-702, Republic of Korea.
authors.forename: Min Jae
authors.initials: MJ
authors.lastname: Shin
authors.affiliation: Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, Gangwon 200-702, Republic of Korea.
authors.forename: Dae Won
authors.initials: DW
authors.lastname: Kim
authors.affiliation: Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, Gangwon 200-702, Republic of Korea.
authors.forename: Jinseu
authors.initials: J
authors.lastname: Park
authors.affiliation: Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, Gangwon 200-702, Republic of Korea.
authors.forename: Soo Young
authors.initials: SY
authors.lastname: Choi
authors.affiliation: Department of Food Science and Nutrition, Hallym University, Chuncheon, Gangwon 200-702, Republic of Korea.
authors.forename: Young-Hee
authors.initials: YH
authors.lastname: Kang
mesh_terms: D050197:Atherosclerosis / Q000235:genetics* / Q000473:pathology; D017362:Cyclic AMP Response Element-Binding Protein; D004730:Endothelium, Vascular / Q000187:drug effects / Q000473:pathology; D061307:Human Umbilical Vein Endothelial Cells; D006801:Humans; D007249:Inflammation / Q000235:genetics* / Q000473:pathology; D009000:Monocytes / Q000378:metabolism / Q000473:pathology; D016328:NF-kappa B / Q000096:biosynthesis; D010084:Oxidation-Reduction / Q000187:drug effects; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000096:biosynthesis / Q000378:metabolism; D021381:Protein Transport / Q000187:drug effects; D017382:Reactive Oxygen Species / Q000378:metabolism; D013482:Superoxide Dismutase / Q000096:biosynthesis / Q000235:genetics*; D000072105:Superoxide Dismutase-1; D015533:Transcriptional Activation; D014161:Transduction, Genetic; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis; D019010:Vascular Cell Adhesion Molecule-1 / Q000096:biosynthesis
chemical_list: C115163:CREB1 protein, human; D017362:Cyclic AMP Response Element-Binding Protein; D016328:NF-kappa B; D019408:Platelet Endothelial Cell Adhesion Molecule-1; D017382:Reactive Oxygen Species; C000606290:SOD1 protein, human; D014409:Tumor Necrosis Factor-alpha; D019010:Vascular Cell Adhesion Molecule-1; D013482:Superoxide Dismutase; D000072105:Superoxide Dismutase-1