title: Vaspin prevents TNF-α-induced intracellular adhesion molecule-1 via inhibiting reactive oxygen species-dependent NF-κB and PKCθ activation in cultured rat vascular smooth muscle cells.
abstract: Vaspin (visceral adipose tissue-derived serine protease inhibitor) was recently identified as a novel adipocytokine with insulin-sensitizing effects. We hypothesized that vaspin could play a role in vascular inflammation. To test the hypothesis, we investigated the effects of vaspin on TNF-α-stimulated vascular smooth muscle cells (SMCs) focusing on inflammatory signal transduction. Vascular SMCs from mesenteric artery of male Wistar rats were treated with TNF-α (5-10 ng/ml, 20 min-6 h) in the absence or presence of vaspin (1-300 ng/ml, pretreatment for 24 h). Western blotting was performed to analyze the cellular signal. Reactive oxygen species (ROS) generation was fluorometrically measured using 2',7'-diclorofluorescein diacetate. Vaspin alone treatment had no effect on vascular SMCs morphology and cellular signal. Vaspin significantly decreased the TNF-α-induced monocyte adhesion to SMCs. Vaspin significantly inhibited the protein expression of intracellular adhesion molecule (ICAM)-1 and the phosphorylation of NF-κB and protein kinase C (PKC)θ induced by TNF-α. Both of NF-κB and novel PKC inhibitors significantly attenuated the TNF-α-induced ICAM-1 expression. Moreover, vaspin inhibited TNF-α-induced ROS generation. An anti-oxidant, N-acetyl-L-cysteine blocked the TNF-α-induced activation of NF-κB, PKCθ and expression of ICAM-1. The present results demonstrated for the first time that vaspin inhibits TNF-α-induced expression of ICAM-1 via preventing the ROS generation and subsequent activation of NF-κB and PKCθ. Consequently, vaspin could play inhibitory roles on inflammatory states of vascular SMCs.
authors.affiliation: Laboratory of Veterinary Pharmacology, School of Veterinary Medicine, Kitasato University, Aomori 034-8628, Japan.
authors.forename: Sukanya
authors.initials: S
authors.lastname: Phalitakul
authors.forename: Muneyoshi
authors.initials: M
authors.lastname: Okada
authors.forename: Yukio
authors.initials: Y
authors.lastname: Hara
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Yamawaki
mesh_terms: D000818:Animals; D002448:Cell Adhesion; D002478:Cells, Cultured; D018799:Intercellular Adhesion Molecule-1 / Q000276:immunology*; D008297:Male; D008638:Mesenteric Arteries / Q000166:cytology; D009000:Monocytes / Q000166:cytology; D009131:Muscle, Smooth, Vascular / Q000276:immunology*; D016328:NF-kappa B / Q000276:immunology*; D011493:Protein Kinase C / Q000276:immunology*; D051381:Rats; D017208:Rats, Wistar; D017382:Reactive Oxygen Species / Q000276:immunology*; D015843:Serpins / Q000276:immunology*; D014409:Tumor Necrosis Factor-alpha / Q000276:immunology*
chemical_list: D016328:NF-kappa B; D017382:Reactive Oxygen Species; C506516:Serpina12 protein, rat; D015843:Serpins; D014409:Tumor Necrosis Factor-alpha; D018799:Intercellular Adhesion Molecule-1; D011493:Protein Kinase C