CD14 Glycoprotein Expressed in Vascular Smooth Muscle Cells

Abstract

Abstract. The inducible nitric oxide synthase (iNOS) expression in vascular smooth muscle cells is an important factor for pathogenesis of septic shock or multiple organ dysfunction syndrome. The mechanisms of iNOS expression in such conditions are partly known. This study tried to clarify the signal transduction of lipopolysaccharide (LPS) single stimulation that induces iNOS mRNA and protein in vascular smooth muscle cells (VSMC). VSMC were primarily cultured from rat aorta. The concentrations of nitrite in culture media were measured by the Griess reaction. Western blottings and immunoreaction for iNOS, nuclear factor kB (NFkB) p65, and CD14 protein were performed. mRNAs of iNOS and tumor necrosis factor (TNF) a were analyzed by RT-PCR. Genistein inhibited LPS induced early phase nitrite production, while pyrrolidine dithiocarbamate (PDTC) inhibited nitrite production at a late phase. PDTC significantly reduced NFk B p65 and iNOS protein expression by LPS. TNFa mRNA expression by LPS was not detected in VSMC. Membranous CD14 glycoprotein was detected in VSMC and soluble CD14 glycoprotein was not detected in fetal bovine serum added in culture media. These results suggest that CD14 glycoprotein is present on the cell membranes of VSMC, a nonmyelomonocyte lineage, acting as an LPS receptor. Activations of tyrosine kinase and NFkB p65 are essential for iNOS expression by LPS single stimulation, while TNFa is not a concern to iNOS expression in VSMC.

Time to abandon dogma: CD14 is expressed by non‐myeloid lineage cells

“…Finally, respiratory epithelial cells, cornea, ciliary body epithelial cells and uroepithelial cells were also found to be CD14 positive 66 , 74 , 75 , 76 , 77 , 78 , 79 . In addition, CD14 expression has been reported on smooth muscle cells, fibroblasts, spermatozoa and pancreatic islet β cells 80 , 81 , 82 , 83 , 84 . The above listed investigators documented the presence of CD14 on the cell surface by either flow cytometry or immunohistochemistry as a first step 66 , 67 , 68 , 69 , 70 , 71 , 72 , 73 , 74 , 79 , 80 , 81 , 82 , 83 , 84 .…”

Exploration of replicative senescence-associated genes in human dermal fibroblasts by cDNA microarray technology

“…For experiments, cells were used in either passage 4 (PD!12) or passage 28 (PDO55), referred to as 'young' and 'old' cells, respectively. VSMC were grown in DMEM containing 10% FBS and 1% antibiotic-antimycotic solution at 37 8C in 5% CO 2 humidified air (Choi and Lee, 2004).…”

The involvement of secondary signaling molecules in cytochrome P-450 1A1-mediated inducible nitric oxide synthase expression in benzo(a)pyrene-treated rat polymorphonuclear leukocytes

“…There are several secondary signaling molecules, including tyrosine kinase, nuclear factor-kappa B (NF-κB), and p38 mitogen-activated protein kinase (MAPK) that activate iNOS by regulating [Ca 2+ ]i (Poljakovic et al, 2003;Nakashima et al, 1999;Ganster et al, 2001;Marlowe and Puga, 2005). A CYP1A1 inhibitor (alphanaphthoflavone), iNOS inhibitor (aminoguanidine), tyrosine kinase inhibitor (genistein), NF-κB inhibitor (pyrrolidine dithiocarbamate, PDTC), p38 MAPK inhibitor (SB202190) and calcium channel blocker (felodipine), have all been used to elucidate the involvement of these signaling molecules in the regulation of [Ca 2+ ]i and activation of iNOS (Kumar et al, 2006;Ziolo et al, 2001;Mene et al, 1999;Delescluse et al, 2000;Nakayama et al, 2006;Feinstein et al, 1994;Comalada et al, 2006;Stefano et al, 2006;Choi and Lee, 2004;Li et al, 2003;Katz et al, 2006). Although the involvement of secondary signaling molecules in benzo(a)pyrene-mediated carcinogenesis is reported in esophageal cells (Chen et al, 2005), due to their variable origins, functions, responses to endogenous and exogenous toxicants, structural stabilities, and life spans of PMNs, it is still worthwhile to examine the involvement of secondary mediators in CYP1A1-mediated iNOS expression in PMNs.…”