IL-1 beta stimulates superoxide and delayed peroxynitrite production by pulmonary vascular smooth muscle cells

Our previous studies have shown that rat pulmonary microvascular smooth muscle cells (RPMSMC) upregulate inducible nitric oxide synthase (iNOS) and produce nitric oxide (NO) when treated with interleukin-1 beta (IL-1 beta). We now report that an additional effect of IL-1 beta stimulation in RPMSMC is an increase in production of superoxide (O2-) that results in the formation of peroxynitrite (ONOO-). IL-1 beta produced a rapid (within 1 h) concentration-dependent increase in O2-, as detected by ferricytochrome c reduction and lucigenin-enhanced chemiluminescence. O2- production was sensitive to quinacrine and diphenyliodinium, suggesting that NADH and NADPH oxidoreductases were responsible. After induction of iNOS and production of iNOS-derived NO, ONOO- was detected by luminol-enhanced chemiluminescence and was found to cause lipid peroxidation and to form nitrotyrosine in the cytoskeleton, detected by immunostaining. Cell viability, however, appeared to be unaffected. IL-1 beta-mediated induction of RPMSMC-derived ONOO- may have significant effects on pulmonary vascular function in sepsis and inflammatory states.

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Ethanol potentiates interleukin-1 β-stimulated inducible nitric oxide synthase expression in cultured vascular smooth muscle cells

Biochemical Journal ◽

10.1042/bj3080231 ◽

1995 ◽

Vol 308 (1) ◽

pp. 231-236 ◽

Cited By ~ 31

Author(s):

W Durante ◽

K Cheng ◽

R K Sunahara ◽

A I Schafer

Keyword(s):

Nitric Oxide ◽

Smooth Muscle ◽

Vascular Smooth Muscle ◽

Smooth Muscle Cells ◽

Vascular Smooth Muscle Cells ◽

Interleukin 1 ◽

Muscle Cells ◽

Inos Mrna ◽

Oxide Synthase ◽

Inducible Nitric Oxide

Experiments were performed to examine the effect of ethanol on the production of nitric oxide from interleukin-1 beta (IL-1 beta)-treated cultured rat aortic smooth muscle cells. Incubation of vascular smooth muscle cells with IL-1 beta resulted in the release of nitrite and in the intracellular accumulation of L-citrulline. In parallel with this, IL-1 beta increased inducible nitric oxide synthase (iNOS) mRNA and protein. Ethanol (6.5-650 mM) potentiated the IL-1 beta-mediated stimulation of iNOS mRNA production, the appearance of iNOS protein and the generation of nitrite and L-citrulline from smooth muscle cells in a concentration-dependent manner. In the absence of IL-1 beta, ethanol failed to induce iNOS expression. These results demonstrate that pharmacologically relevant concentrations of ethanol enhance the IL-1 beta-induced expression of the iNOS gene in vascular smooth muscle. The ability of ethanol to augment the release of the platelet inhibitor and vasodilator nitric oxide may, in part, contribute to the beneficial cardiovascular effects associated with moderate alcohol consumption.

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Thrombin Prevents the Expression of Inducible Nitric Oxide Synthase in Vascular Smooth Muscle Cells by a Proteolytically-Activated Thrombin Receptor

Thrombosis and Haemostasis ◽

10.1055/s-0038-1649859 ◽

1995 ◽

Vol 74 (03) ◽

pp. 980-986 ◽

Cited By ~ 8

Author(s):

Valérie B Schini-Kerth ◽

Beate Fißithaler ◽

Thomas T Andersen ◽

John W Fenton ◽

Paul M Vanhoutte ◽

...

Keyword(s):

Nitric Oxide ◽

Smooth Muscle ◽

Vascular Smooth Muscle ◽

Smooth Muscle Cells ◽

Vascular Smooth Muscle Cells ◽

Inducible Nitric Oxide Synthase ◽

Muscle Cells ◽

Thrombin Receptor ◽

Oxide Synthase ◽

Inducible Nitric Oxide

SummaryProteolytically active forms of thrombin (α- and γ-thrombin) and thrombin receptor peptides inhibited the release of nitrite, a stable endproduct of nitric oxide, evoked by interleukin-1 β(IL-1 β) in cultured vascular smooth muscle cells while proteolytically inactive forms [D-Phe-Pro-Arg chloromethyl ketone-α-thrombin (PPACK-α- thrombin) and diisopropylphosphoryl-α-thrombin (DIP-α-thrombin)] had either no or only minimal inhibitory effects. Under bioassay conditions, perfusates from columns containing IL-1 β-activated vascular smooth muscle cells or cells treated with IL-1βplus PPACK-α-thrombin relaxed detector blood vessels. These relaxations were abolished by the inhibitor of nitric oxide synthesis, NG-nitro-L arginine. No relaxations were obtained with untreated cells or IL-1 β-treated cells in the presence of α-thrombin. The expression of inducible nitric oxide synthase mRNA and protein in vascular smooth muscle cells by IL-1 β was impaired by α-thrombin. These results demonstrate that thrombin regulates the expression of the inducible nitric oxide synthase at a transcriptional level via the proteolytic activation of the thrombin receptor in vascular smooth muscle cells

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