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• W2080931868 abstract "Nitric oxide (NO) increases tumor necrosis factor (TNF) synthesis in human peripheral blood mononuclear cells by a cGMP-independent mechanism. NO has been shown to inhibit adenylate cyclase in cell membranes. Since cAMP down-regulates TNF transcription, we examined the possibility that NO enhances TNF synthesis by decreasing cAMP. U937 cells were induced to differentiate using phorbol myristate acetate (100 nM for 48 h) and then were incubated for 24 h with sodium nitroprusside (SNP) or S-nitroso-N-acetylpenicillamine (SNAP). These NO donors increased TNF production (7.0- and 15.6-fold, respectively, at 500 μM) in a dose-dependent manner (p = 0.002). However, SNP and SNAP did not elevate cGMP levels in U937 cell cultures, and the cGMP analog, 8-bromo-cGMP, had no effect on TNF production. In contrast, SNP (p = 0.001) and SNAP (p = 0.009) decreased intracellular cAMP levels by up to 51.5% over 24 h and, in the presence of a phosphodiesterase inhibitor, blunted isoproterenol-stimulated increases in cAMP by 21.8% (p = 0.004) and 27.6% (p = 0.008), respectively. H89, an inhibitor of cAMP-dependent protein kinase, dose dependently increased TNF production in phorbol myristate acetate-differentiated U937 cells in the absence (6.5-fold at 30 μM; p = 0.035), but not in the presence (p = 0.77) of SNAP. Conversely, the cAMP analog dibutyryl cAMP (Bt2cAMP) blocked SNAP-induced TNF production (p = 0.001). SNP and SNAP (500 μM) increased relative TNF mRNA levels by 57.5% (p = 0.045) and 66.2% (p = 0.001), respectively. This effect was prevented by Bt2cAMP. These results indicate that NO up-regulates TNF production by decreasing intracellular cAMP. Nitric oxide (NO) increases tumor necrosis factor (TNF) synthesis in human peripheral blood mononuclear cells by a cGMP-independent mechanism. NO has been shown to inhibit adenylate cyclase in cell membranes. Since cAMP down-regulates TNF transcription, we examined the possibility that NO enhances TNF synthesis by decreasing cAMP. U937 cells were induced to differentiate using phorbol myristate acetate (100 nM for 48 h) and then were incubated for 24 h with sodium nitroprusside (SNP) or S-nitroso-N-acetylpenicillamine (SNAP). These NO donors increased TNF production (7.0- and 15.6-fold, respectively, at 500 μM) in a dose-dependent manner (p = 0.002). However, SNP and SNAP did not elevate cGMP levels in U937 cell cultures, and the cGMP analog, 8-bromo-cGMP, had no effect on TNF production. In contrast, SNP (p = 0.001) and SNAP (p = 0.009) decreased intracellular cAMP levels by up to 51.5% over 24 h and, in the presence of a phosphodiesterase inhibitor, blunted isoproterenol-stimulated increases in cAMP by 21.8% (p = 0.004) and 27.6% (p = 0.008), respectively. H89, an inhibitor of cAMP-dependent protein kinase, dose dependently increased TNF production in phorbol myristate acetate-differentiated U937 cells in the absence (6.5-fold at 30 μM; p = 0.035), but not in the presence (p = 0.77) of SNAP. Conversely, the cAMP analog dibutyryl cAMP (Bt2cAMP) blocked SNAP-induced TNF production (p = 0.001). SNP and SNAP (500 μM) increased relative TNF mRNA levels by 57.5% (p = 0.045) and 66.2% (p = 0.001), respectively. This effect was prevented by Bt2cAMP. These results indicate that NO up-regulates TNF production by decreasing intracellular cAMP. INTRODUCTIONNitric oxide (NO) 1The abbreviations used are: NOnitric oxideTNFαtumor necrosis factor αPKAcAMP-dependent protein kinasePMAphorbol myristate acetateSNAPS-nitroso-N-acetylpenicillamineBt2cGMPdibutyryl cGMPBt2cAMPdibutyryl cAMPSNPsodium nitroprussidePGE2prostaglandin E2IBMX3-isobutyl-1-methylxanthineHBSS−Hank's balanced salt solution without Ca2+ and Mg2+HBSS+Hank's balanced salt solution with Ca2+ and Mg2+PDEphosphodiesteraseRPAribonuclease protection assay. is a free-radical gas produced by many cell types (1Pollock J.S. Förstermann U. Mitchell J.A. Warner T.D. Schmidt H.H.H.W. Nakane M. Murad F. Proc. Natl. Acad. Sci. U. S. A. 1991; 88: 10480-10484Crossref PubMed Scopus (889) Google Scholar, 2Sessa W.C. Harrison J.K. Barber C.M. Zeng D. Durieux M.E. D'Angelo D.D. Lynch K.R. Peach M.J. J. Biol. Chem. 1992; 267: 15274-15276Abstract Full Text PDF PubMed Google Scholar, 3Busse R. Mülsch A. FEBS Lett. 1990; 275: 87-90Crossref PubMed Scopus (663) Google Scholar, 4Förstermann U. Kleinnert H. Gath I. Schwarz P. Closs E.J. Dunn N.J. Adv. Pharmacol. 1995; 34: 171-186Crossref PubMed Scopus (83) Google Scholar). NO has a diverse repertoire of important functions (5Bredt D.S. Hwang P.M. Snyder S.H. Nature. 1990; 347: 768-770Crossref PubMed Scopus (2677) Google Scholar, 6Shibuki K. Okada D. Nature. 1991; 349: 326-328Crossref PubMed Scopus (792) Google Scholar, 7Nathan C. FASEB J. 1992; 6: 3051-3064Crossref PubMed Scopus (4132) Google Scholar, 8Moncada S. Palmer R.M.J. Higgs E.A. Pharmacol. Rev. 1991; 43: 109-142PubMed Google Scholar, 9Lowenstein C.J. Snyder S.S. Cell. 1992; 70: 705-707Abstract Full Text PDF PubMed Scopus (736) Google Scholar) including neurotransmission (5Bredt D.S. Hwang P.M. Snyder S.H. Nature. 1990; 347: 768-770Crossref PubMed Scopus (2677) Google Scholar, 10Garthwaite J. Charles S.L. Chess-Williams R. Nature. 1988; 336: 385-388Crossref PubMed Scopus (2267) Google Scholar), vasodilatation (11Palmer R.M.J. Ashton D.S. Moncada S. Nature. 1988; 333: 664-666Crossref PubMed Scopus (4094) Google Scholar), antiplatelet activity, and immune modulation (12Mellion B.T. Ignarro L.J. Ohlstein E.H. Pontecorvo E.G. Hyman A.L. Kadowitz P.J. Blood. 1981; 57: 946-955Crossref PubMed Google Scholar, 13Evans C.H. Agents Actions Suppl. 1995; 47: 107-116PubMed Google Scholar, 14Moilanen E. Vapaatalo H. Ann. Med. 1995; 27: 359-367Crossref PubMed Scopus (216) Google Scholar). Most of these effects are mediated through a unique cGMP signaling pathway. NO covalently attacks the heme moiety of soluble guanylate cyclase, activating the enzyme, and thereby elevating intracellular cGMP concentrations (15Ignarro L.J. Degna J.N. Baricos W.H. Kadowitz P.J. Wolin M.S. Biochem. Biophys. Acta. 1982; 718: 49-59Crossref PubMed Scopus (223) Google Scholar, 16Craven P.A. DeRubertis F.R. J. Biol. Chem. 1978; 253: 8433-8443Abstract Full Text PDF PubMed Google Scholar, 17Ignarro L.J. Pharmacol. Toxicol. 1990; 67: 1-7Crossref PubMed Scopus (208) Google Scholar). This increase in cGMP subsequently activates certain protein kinases, which phosphorylate target proteins involved in regulation of cell function (17Ignarro L.J. Pharmacol. Toxicol. 1990; 67: 1-7Crossref PubMed Scopus (208) Google Scholar, 18Stewart A.G. Phan L.H. Grigoriadis G. Microsurgery. 1994; 15: 693-702Crossref PubMed Scopus (49) Google Scholar, 19Kuo P.C. Schroeder R.A. Ann. Surg. 1995; 221: 220-235Crossref PubMed Scopus (242) Google Scholar). Although the role of cGMP as a NO second messenger is undisputed, some findings have led to speculation about the existence of cGMP-independent signal transduction pathways for NO.First, NO is a free radical with the ability to react with a variety of enzymes besides soluble guanylate cyclase. NO has been shown to catalyze the covalent binding of NAD to glyceraldehyde-3-phosphate dehydrogenase (20McDonald L.J. Moss J. Proc. Natl. Acad. Sci. U. S. A. 1993; 90: 6238-6241Crossref PubMed Scopus (176) Google Scholar), oxidize iron-containing proteins such as aconitase or ribonucleotide reductase (21Drapier J.C. Hibbs Jr., J.B. J. Clin. Invest. 1986; 78: 790-797Crossref PubMed Scopus (366) Google Scholar, 22Lepoivre M. Chenais B. Yapo A. Lemaire G. Thelander L. Tenu J-P. J. Biol. Chem. 1990; 265: 14143-14149Abstract Full Text PDF PubMed Google Scholar, 23Stamler J.S. Cell. 1994; 78: 931-936Abstract Full Text PDF PubMed Scopus (1629) Google Scholar), and nitrosylate tyrosine and cysteine residues in a variety of proteins (24Stamler J.S. Simon D.I. Osborne J.A. Mullins M.E. Jarak O. Michel T. Singel D.J. Lascalzo J. Proc. Natl. Acad. Sci. U. S. A. 1992; 89: 444-448Crossref PubMed Scopus (1292) Google Scholar, 25Arnell D.K. Stamler J.S. Arch. Biochem. Biophys. 1995; 318: 279-285Crossref PubMed Scopus (537) Google Scholar, 26Lander H.M. Ogiste J.S. Pearce S.F.A. Levi R. Novogrodsky A. J. Biol. Chem. 1995; 270: 7017-7020Abstract Full Text Full Text PDF PubMed Scopus (333) Google Scholar). Second, some effects of NO cannot be reproduced with cell permeable cGMP analogs. For example, the synthesis of tumor necrosis factor α (TNFα), a proinflammatory cytokine implicated in tissue injury and shock (27Tracey K.J. Beutler B. Lowry S.F. Merryweather J. Wolpe S. Milsark I.W. Hariri R.J. Fahey III, T.J. Zentella A. Albert J.D. Shires G.T. Cerami A. Science. 1986; 234: 470-474Crossref PubMed Scopus (2107) Google Scholar), is increased in human peripheral blood mononuclear cells (28Van Dervort A.L. Yan L. Madara P.J. Cobb P.J. Wesley R.A. Corriveau C.C. Tropea M.M. Danner R.L. J. Immunol. 1994; 152: 4102-4109PubMed Google Scholar) and lipopolysaccharide-stimulated neutrophil preparations (29Lander H.M. Sehajpal P. Levine D.M. Novogrodsky A. J. Immunol. 1993; 150: 1509-1516PubMed Google Scholar) by exogenous NO. Although NO increases cGMP concentrations in these cells, cGMP analogs have no effect on TNFα production (28Van Dervort A.L. Yan L. Madara P.J. Cobb P.J. Wesley R.A. Corriveau C.C. Tropea M.M. Danner R.L. J. Immunol. 1994; 152: 4102-4109PubMed Google Scholar, 29Lander H.M. Sehajpal P. Levine D.M. Novogrodsky A. J. Immunol. 1993; 150: 1509-1516PubMed Google Scholar). Collectively, these investigations suggest that NO might use cGMP-independent signaling pathways for some of its cellular functions.Recently, adenylate cyclase has been added to the list of enzymes that can be modified by NO (30Duhe R.J. Nielsen M.D. Dittman A.H. Villacres E.C. Choi E-J. Storm D.R. J. Biol. Chem. 1994; 269: 7290-7296Abstract Full Text PDF PubMed Google Scholar). Treatment of cell membranes with NO decreases cAMP production by inhibiting calmodulin activation of type I adenylate cyclase, presumably through thiol nitrosylation at the calmodulin-binding site (30Duhe R.J. Nielsen M.D. Dittman A.H. Villacres E.C. Choi E-J. Storm D.R. J. Biol. Chem. 1994; 269: 7290-7296Abstract Full Text PDF PubMed Google Scholar, 31Vorherr T. Knöpfel L. Hofmann F. Mollner S. Pfeuffer T. Carafoli E. Biochemistry. 1993; 32: 6081-6088Crossref PubMed Scopus (139) Google Scholar). Notably, increases in cAMP in leukocytes activate cAMP-dependent protein kinase (PKA). This kinase phosphorylates transcription factors that bind to the cAMP-response element on the TNFα promoter, thereby inhibiting TNFα mRNA transcription (32Economou J.S. Rhoades K. Essner R. Mcbride W.H. Gasson J.C. Morton D.L. J. Exp. Med. 1989; 170: 321-326Crossref PubMed Scopus (99) Google Scholar, 33Newell C.L. Deisseroth A.B. Lopez-Berestein G. J. Leukocyte Biol. 1994; 56: 27-35Crossref PubMed Scopus (116) Google Scholar, 34Righi M. Funct. Neurol. 1993; 8: 359-363PubMed Google Scholar, 35Zhong W.W. Burke P.A. Drotar M.E. Chavali S.R. Frose R.A. Immunology. 1995; 84: 446-452PubMed Google Scholar). The effect of NO on type I adenylate cyclase suggests that NO might up-regulate TNFα synthesis in human monocytes by decreasing cAMP concentrations.We investigated this question using U937 cells, a human monocytic cell line that differentiates into monocyte-macrophage-like cells and produces TNFα when exposed to phorbol myristate acetate (PMA) (36Sundström C. Nilsson K. Int. J. Cancer. 1976; 17: 565-577Crossref PubMed Scopus (1947) Google Scholar, 37Hass R. Lonnemann G. Männel D. Topley N. Hartmann A. Köhler L. Resch K. Goppelt-Strübe M. Leukemia Res. 1991; 15: 327-339Crossref PubMed Scopus (43) Google Scholar, 38Taimi M. Defacque H. Commes T. Favero J. Leukemia Res. 1993; 79: 229-235Google Scholar). The specific objectives were as follows: 1) to demonstrate that NO up-regulates TNFα production in PMA-differentiated U937 cells and test the cGMP-dependence of this effect; 2) to determine whether NO alters resting or stimulated cAMP concentrations in intact cells; 3) to investigate the effect of inhibitors or activators of PKA on NO-stimulated TNFα production in this system; and 4) to determine if NO-induced changes in TNFα mRNA levels were consistent with a cAMP mechanism.DISCUSSIONWe demonstrated that NO increased TNFα production in PMA-differentiated U937 cells by decreasing intracellular cAMP levels, indicating that NO uses cAMP, rather than cGMP as a second messenger for some of its cellular effects. This conclusion is based on these findings: 1) two structurally dissimilar NO donors increased TNFα production in a dose-dependent manner; 2) both SNP and SNAP increased cGMP concentrations in human neutrophil cultures, but had no effect on cGMP concentrations in PMA-differentiated U937 cell cultures; 3) cell-permeable analogs of cGMP, 8-bromo-cGMP and Bt2cGMP, did not alter TNFα production by PMA-differentiated U937 cells; 4) SNP or SNAP not only decreased intracellular cAMP in a dose-dependent manner, but also blunted isoproterenol- and PGE2-stimulated cAMP responses in PMA-differentiated U937 cells; 5) an inhibitor of PKA, H89, increased TNFα release in the absence but not in the presence of SNAP; 6) conversely, an activator of PKA, Bt2cAMP, abolished the effect of SNAP on TNFα production; and 7) finally, NO donors and Bt2cAMP but not 8-bromo-cGMP caused changes in relative TNFα mRNA levels that were consistent with a cAMP mechanism for the observed effects of NO. Collectively, these experiments demonstrate that NO-induced up-regulation of TNFα production in this human cell line uses cAMP, not cGMP, as its second messenger.Many of the known effects of NO have been attributed to its ability to generate cGMP through its action on soluble guanylate cyclase (15Ignarro L.J. Degna J.N. Baricos W.H. Kadowitz P.J. Wolin M.S. Biochem. Biophys. Acta. 1982; 718: 49-59Crossref PubMed Scopus (223) Google Scholar, 16Craven P.A. DeRubertis F.R. J. Biol. Chem. 1978; 253: 8433-8443Abstract Full Text PDF PubMed Google Scholar, 17Ignarro L.J. Pharmacol. Toxicol. 1990; 67: 1-7Crossref PubMed Scopus (208) Google Scholar, 18Stewart A.G. Phan L.H. Grigoriadis G. Microsurgery. 1994; 15: 693-702Crossref PubMed Scopus (49) Google Scholar). However, we were unable to demonstrate that NO donors increase cGMP in either naive or differentiated U937 cells. It seems unlikely that our inability to detect NO-stimulated increases in cGMP was due to degradation of cGMP. U937 cells have extremely low cGMP hydrolytic activity and do not contain the cGMP-specific PDE isoenzyme (PDE V) (45Torphy T.J. Zhou H-L. Cieslinski L.B. J. Pharmacol. Exp. Ther. 1992; 263: 1195-1205PubMed Google Scholar, 46Barnette M.S. Grous M. Burman M. Cieslinski L.B. Huang L. Torphy T.J. Am. Rev. Resp. Dis. 1992; 145: A282-A283Google Scholar). Furthermore, our experiments were conducted in the presence of a potent, nonselective PDE inhibitor. These data indicate that U937 cells lack NO-sensitive soluble guanylate cyclase. Moreover, membrane permeable cGMP analogs, 8-bromo-cGMP and Bt2cGMP, were unable to mimic the effect of NO on TNFα production, a finding that has also been reported in human peripheral blood mononuclear cells and neutrophil preparations (28Van Dervort A.L. Yan L. Madara P.J. Cobb P.J. Wesley R.A. Corriveau C.C. Tropea M.M. Danner R.L. J. Immunol. 1994; 152: 4102-4109PubMed Google Scholar, 29Lander H.M. Sehajpal P. Levine D.M. Novogrodsky A. J. Immunol. 1993; 150: 1509-1516PubMed Google Scholar). These results further suggest that NO regulates TNFα production in PMA-differentiated U937 cells by a cGMP-independent mechanism.The ability of NO to decrease intracellular cAMP levels and blunt isoproterenol- and PGE2-stimulated cAMP responses provide direct evidence for our speculation that NO increases TNFα production in PMA-differentiated U937 cells by decreasing cAMP levels. Decreases in intracellular cAMP can result either from its reduced synthesis by adenylate cyclase or from increased catabolism due to increased PDE activity (47Gill G.N. Gim W. Adv. Cyclic. Nucleotide Res. 1979; 10: 93-106PubMed Google Scholar). The result that NO decreased cAMP concentrations in the presence of IBMX, a nonspecific PDE inhibitor, support the hypothesis that changes in cAMP levels were due to decreased synthesis, rather than increased catabolism by PDE. Interestingly, cGMP can either increase cAMP hydrolysis by activating PDE II (45Torphy T.J. Zhou H-L. Cieslinski L.B. J. Pharmacol. Exp. Ther. 1992; 263: 1195-1205PubMed Google Scholar, 46Barnette M.S. Grous M. Burman M. Cieslinski L.B. Huang L. Torphy T.J. Am. Rev. Resp. Dis. 1992; 145: A282-A283Google Scholar) or decrease cAMP hydrolysis by inhibiting PDE III (48Sonnebury W.K. Beavo J.A. Adv. Pharmacol. 1994; 26: 87-114Crossref PubMed Scopus (75) Google Scholar, 49Beavo J.A. Physiol. Rev. 1995; 75: 725-748Crossref PubMed Scopus (1634) Google Scholar). Increased or decreased cAMP hydrolysis mediated by cGMP is unlikely in our experiments since U937 cells lack PDE II activity (45Torphy T.J. Zhou H-L. Cieslinski L.B. J. Pharmacol. Exp. Ther. 1992; 263: 1195-1205PubMed Google Scholar, 46Barnette M.S. Grous M. Burman M. Cieslinski L.B. Huang L. Torphy T.J. Am. Rev. Resp. Dis. 1992; 145: A282-A283Google Scholar), a PDE inhibitor was used, and as shown here, U937 cells do not produce cGMP in response to a NO signal. However, in other cell types that contain NO-sensitive soluble guanylate cyclase, the ability of NO to decrease cAMP production may be masked by decreased cAMP hydrolysis via cGMP-mediated inhibition of PDE III activity (48Sonnebury W.K. Beavo J.A. Adv. Pharmacol. 1994; 26: 87-114Crossref PubMed Scopus (75) Google Scholar, 49Beavo J.A. Physiol. Rev. 1995; 75: 725-748Crossref PubMed Scopus (1634) Google Scholar, 50Turner N.C. Lamb J. Worby A. Murray K.J. Br. J. Pharmacol. 1994; 111: 1047-1052Crossref PubMed Scopus (18) Google Scholar, 51Bowen R. Haslam R.J. J. Cardiovasc. Pharmacol. 1991; 17: 424-433Crossref PubMed Scopus (56) Google Scholar).As already noted, NO has been shown to inhibit calmodulin-dependent adenylate cyclase activity in isolated cell membranes by oxidizing cysteine residues at the calmodulin-binding site (30Duhe R.J. Nielsen M.D. Dittman A.H. Villacres E.C. Choi E-J. Storm D.R. J. Biol. Chem. 1994; 269: 7290-7296Abstract Full Text PDF PubMed Google Scholar). Other studies have shown that calcium ionophores potentiate cAMP responses in human peripheral blood mononuclear cells and neutrophils stimulated with isoproterenol and PGE2, and this potentiation was inhibited by calmodulin inhibitors (52Iannone M.A. Wolberg G. Zimmerman T.P. Biochem. Pharmacol. 1991; 42,: S105-S111Crossref PubMed Scopus (10) Google Scholar, 53Ishitoya J. Takenawa T. J. Immunol. 1987; 138: 1201-1207PubMed Google Scholar, 54Dooper M.W.S.M. Hoekstra Y. Timmermans A.D.E. Monchy J.G.R. Kauffman H.F. Biochem. Pharmacol. 1994; 47: 289-294Crossref PubMed Scopus (10) Google Scholar). These observations indicate that the calmodulindependent adenylate cyclase subtype that is inhibited by NO is present in human leukocytes. Although this suggests a possible mechanism for NO modulation of intracellular cAMP levels, other possibilities exist. Substitution of cysteine residues for other amino acids in the β2-adrenergic receptor markedly shifts the dose-response curve to the right for isoproterenol-stimulated increases in intracellular cAMP concentrations (55Savarese T.M. Fraser C.M. Biochem. J. 1992; 283: 1-19Crossref PubMed Scopus (439) Google Scholar). This suggests that NO could reduce agonist-stimulated cAMP responses by decreasing receptor affinity through the nitrosylation of key cysteine-containing domains.Inhibitors and activators of PKA were used to further explore the possibility that NO was using a cAMP-dependent signaling pathway. H89, a specific cell-permeable inhibitor of PKA (56Chijiwa T. Mishima A. Hagiwara M. Sano M. Hayashi K. Inoue T. Naito K. Toshioka T. Hidaka H. J. Biol. Chem. 1990; 265: 5267-5272Abstract Full Text PDF PubMed Google Scholar), dose-dependently increased TNFα release. This finding demonstrates in PMA-differentiated U937 cells that basal cAMP levels and the resulting degree of PKA activation are inhibitory of TNFα synthesis. Interestingly, H89, at the doses tested, did not further up-regulate SNAP-induced TNFα production, suggesting that PKA was maximally inactivated by the decrease in cAMP levels caused by NO. In contrast, Bt2cAMP only slightly suppressed basal TNFα release, but completely abolished SNAP-induced increases in TNFα production. This cAMP analog can permeate cell membranes and is resistant to hydrolysis by PDE (57Postenak T. Weiman G. Methods Enzymol. 1974; 38: 399-417Crossref PubMed Scopus (43) Google Scholar), enabling it to persist in cell cultures and mimic prolonged elevations of intracellular cAMP. Toxicity caused by the butyrate moiety of the Bt2cAMP molecule was unlikely to be responsible for this effect, since the concentrations of Bt2cAMP used were relatively low and Bt2cGMP (up to 1 mM), which also contains a butyrate moiety did not alter TNFα production. Furthermore, cell viability by trypan blue exclusion was not decreased by Bt2cAMP. Together, these results reinforced our conclusion that NO increases TNFα production in PMA-differentiated U937 cells by decreasing cAMP levels.Similarly, NO donors were also found to increase relative TNFα mRNA levels and Bt2cAMP completely prevented this effect. An analog of cGMP, 8-bromo-cGMP, had no effect. These results are consistent with a cAMP mechanism acting at the level of transcription for the observed effects of NO on TNFα production in PMA-differentiated U937 cells. Evidence is also available that cAMP can down-regulate TNFα expression at a post-transcriptional level in monocytes and macrophages (58Kunkel S.L. Spengler M. May M.A. Spengler R. Larrick J. Remick D. J. Biol. Chem. 1988; 263: 5380-5384Abstract Full Text PDF PubMed Google Scholar, 59Prabhakar U. Lipshutz D. Bartus J.O. Slivjak M.J. Smith III, E.F. Lee J. Esser K.M. Int. J. Immunopharmacol. 1994; 16: 805-816Crossref PubMed Scopus (132) Google Scholar, 60Seldon P.M. Barnes P.J. Meja K. Giembycz M.A. Mol. Pharmacol. 1995; 48: 747-757PubMed Google Scholar).Previously, NO was demonstrated to increase TNFα mRNA levels in HL-60 cells (61Magrinat G. Nickmason S. Shami P.J. Weinberg J.B. Blood. 1992; 180: 1880-1884Crossref Google Scholar), but we found no change in TNFα mRNA levels in human neutrophil preparations (28Van Dervort A.L. Yan L. Madara P.J. Cobb P.J. Wesley R.A. Corriveau C.C. Tropea M.M. Danner R.L. J. Immunol. 1994; 152: 4102-4109PubMed Google Scholar). These inconsistent findings may be ascribed to the different methods employed to measure mRNA levels. In our present study, we measured TNFα mRNA levels using a RPA, which may be quantitatively more reliable than the reverse transcription polymerase chain reaction assay used in our previous experiments with neutrophils (28Van Dervort A.L. Yan L. Madara P.J. Cobb P.J. Wesley R.A. Corriveau C.C. Tropea M.M. Danner R.L. J. Immunol. 1994; 152: 4102-4109PubMed Google Scholar). Furthermore, differentiated U937 cells may contain more copies of TNFα mRNA than neutrophils. Besides the cAMP mechanism, our data do not exclude the possibility of additional mechanisms for the up-regulation of TNFα production by NO. For example, NO could activate or induce other transcription factors, such as NF-κB (29Lander H.M. Sehajpal P. Levine D.M. Novogrodsky A. J. Immunol. 1993; 150: 1509-1516PubMed Google Scholar).In conclusion, the present study indicates that NO increase TNFα production in PMA-differentiated U937 cells by decreasing intracellular cAMP. To our knowledge, this is the first demonstration in intact cells that NO signal transduction can use cAMP rather than cGMP to regulate cell function. INTRODUCTIONNitric oxide (NO) 1The abbreviations used are: NOnitric oxideTNFαtumor necrosis factor αPKAcAMP-dependent protein kinasePMAphorbol myristate acetateSNAPS-nitroso-N-acetylpenicillamineBt2cGMPdibutyryl cGMPBt2cAMPdibutyryl cAMPSNPsodium nitroprussidePGE2prostaglandin E2IBMX3-isobutyl-1-methylxanthineHBSS−Hank's balanced salt solution without Ca2+ and Mg2+HBSS+Hank's balanced salt solution with Ca2+ and Mg2+PDEphosphodiesteraseRPAribonuclease protection assay. is a free-radical gas produced by many cell types (1Pollock J.S. Förstermann U. Mitchell J.A. Warner T.D. Schmidt H.H.H.W. Nakane M. Murad F. Proc. Natl. Acad. Sci. U. S. A. 1991; 88: 10480-10484Crossref PubMed Scopus (889) Google Scholar, 2Sessa W.C. Harrison J.K. Barber C.M. Zeng D. Durieux M.E. D'Angelo D.D. Lynch K.R. Peach M.J. J. Biol. Chem. 1992; 267: 15274-15276Abstract Full Text PDF PubMed Google Scholar, 3Busse R. Mülsch A. FEBS Lett. 1990; 275: 87-90Crossref PubMed Scopus (663) Google Scholar, 4Förstermann U. Kleinnert H. Gath I. Schwarz P. Closs E.J. Dunn N.J. Adv. Pharmacol. 1995; 34: 171-186Crossref PubMed Scopus (83) Google Scholar). NO has a diverse repertoire of important functions (5Bredt D.S. Hwang P.M. Snyder S.H. Nature. 1990; 347: 768-770Crossref PubMed Scopus (2677) Google Scholar, 6Shibuki K. Okada D. Nature. 1991; 349: 326-328Crossref PubMed Scopus (792) Google Scholar, 7Nathan C. FASEB J. 1992; 6: 3051-3064Crossref PubMed Scopus (4132) Google Scholar, 8Moncada S. Palmer R.M.J. Higgs E.A. Pharmacol. Rev. 1991; 43: 109-142PubMed Google Scholar, 9Lowenstein C.J. Snyder S.S. Cell. 1992; 70: 705-707Abstract Full Text PDF PubMed Scopus (736) Google Scholar) including neurotransmission (5Bredt D.S. Hwang P.M. Snyder S.H. Nature. 1990; 347: 768-770Crossref PubMed Scopus (2677) Google Scholar, 10Garthwaite J. Charles S.L. Chess-Williams R. Nature. 1988; 336: 385-388Crossref PubMed Scopus (2267) Google Scholar), vasodilatation (11Palmer R.M.J. Ashton D.S. Moncada S. Nature. 1988; 333: 664-666Crossref PubMed Scopus (4094) Google Scholar), antiplatelet activity, and immune modulation (12Mellion B.T. Ignarro L.J. Ohlstein E.H. Pontecorvo E.G. Hyman A.L. Kadowitz P.J. Blood. 1981; 57: 946-955Crossref PubMed Google Scholar, 13Evans C.H. Agents Actions Suppl. 1995; 47: 107-116PubMed Google Scholar, 14Moilanen E. Vapaatalo H. Ann. Med. 1995; 27: 359-367Crossref PubMed Scopus (216) Google Scholar). Most of these effects are mediated through a unique cGMP signaling pathway. NO covalently attacks the heme moiety of soluble guanylate cyclase, activating the enzyme, and thereby elevating intracellular cGMP concentrations (15Ignarro L.J. Degna J.N. Baricos W.H. Kadowitz P.J. Wolin M.S. Biochem. Biophys. Acta. 1982; 718: 49-59Crossref PubMed Scopus (223) Google Scholar, 16Craven P.A. DeRubertis F.R. J. Biol. Chem. 1978; 253: 8433-8443Abstract Full Text PDF PubMed Google Scholar, 17Ignarro L.J. Pharmacol. Toxicol. 1990; 67: 1-7Crossref PubMed Scopus (208) Google Scholar). This increase in cGMP subsequently activates certain protein kinases, which phosphorylate target proteins involved in regulation of cell function (17Ignarro L.J. Pharmacol. Toxicol. 1990; 67: 1-7Crossref PubMed Scopus (208) Google Scholar, 18Stewart A.G. Phan L.H. Grigoriadis G. Microsurgery. 1994; 15: 693-702Crossref PubMed Scopus (49) Google Scholar, 19Kuo P.C. Schroeder R.A. Ann. Surg. 1995; 221: 220-235Crossref PubMed Scopus (242) Google Scholar). Although the role of cGMP as a NO second messenger is undisputed, some findings have led to speculation about the existence of cGMP-independent signal transduction pathways for NO.First, NO is a free radical with the ability to react with a variety of enzymes besides soluble guanylate cyclase. NO has been shown to catalyze the covalent binding of NAD to glyceraldehyde-3-phosphate dehydrogenase (20McDonald L.J. Moss J. Proc. Natl. Acad. Sci. U. S. A. 1993; 90: 6238-6241Crossref PubMed Scopus (176) Google Scholar), oxidize iron-containing proteins such as aconitase or ribonucleotide reductase (21Drapier J.C. Hibbs Jr., J.B. J. Clin. Invest. 1986; 78: 790-797Crossref PubMed Scopus (366) Google Scholar, 22Lepoivre M. Chenais B. Yapo A. Lemaire G. Thelander L. Tenu J-P. J. Biol. Chem. 1990; 265: 14143-14149Abstract Full Text PDF PubMed Google Scholar, 23Stamler J.S. Cell. 1994; 78: 931-936Abstract Full Text PDF PubMed Scopus (1629) Google Scholar), and nitrosylate tyrosine and cysteine residues in a variety of proteins (24Stamler J.S. Simon D.I. Osborne J.A. Mullins M.E. Jarak O. Michel T. Singel D.J. Lascalzo J. Proc. Natl. Acad. Sci. U. S. A. 1992; 89: 444-448Crossref PubMed Scopus (1292) Google Scholar, 25Arnell D.K. Stamler J.S. Arch. Biochem. Biophys. 1995; 318: 279-285Crossref PubMed Scopus (537) Google Scholar, 26Lander H.M. Ogiste J.S. Pearce S.F.A. Levi R. Novogrodsky A. J. Biol. Chem. 1995; 270: 7017-7020Abstract Full Text Full Text PDF PubMed Scopus (333) Google Scholar). Second, some effects of NO cannot be reproduced with cell permeable cGMP analogs. For example, the synthesis of tumor necrosis factor α (TNFα), a proinflammatory cytokine implicated in tissue injury and shock (27Tracey K.J. Beutler B. Lowry S.F. Merryweather J. Wolpe S. Milsark I.W. Hariri R.J. Fahey III, T.J. Zentella A. Albert J.D. Shires G.T. Cerami A. Science. 1986; 234: 470-474Crossref PubMed Scopus (2107) Google Scholar), is increased in human peripheral blood mononuclear cells (28Van Dervort A.L. Yan L. Madara P.J. Cobb P.J. Wesley R.A. Corriveau C.C. Tropea M.M. Danner R.L. J. Immunol. 1994; 152: 4102-4109PubMed Google Scholar) and lipopolysaccharide-stimulated neutrophil preparations (29Lander H.M. Sehajpal P. Levine D.M. Novogrodsky A. J. Immunol. 1993; 150: 1509-1516PubMed Google Scholar) by exogenous NO. Although NO increases cGMP concentrations in these cells, cGMP analogs have no effect on TNFα production (28Van Dervort A.L. Yan L. Madara P.J. Cobb P.J. Wesley R.A. Corriveau C.C. Tropea M.M. Danner R.L. J. Immunol. 1994; 152: 4102-4109PubMed Google Scholar, 29Lander H.M. Sehajpal P. Levine D.M. Novogrodsky A. J. Immunol. 1993; 150: 1509-1516PubMed Google Scholar). Collectively, these investigations suggest that NO might use cGMP-independent signaling pathways for some of its cellular functions.Recently, adenylate cyclase has been added to the list of enzymes that can be modified by NO (30Duhe R.J. Nielsen M.D. Dittman A.H. Villacres E.C. Choi E-J. Storm D.R. J. Biol. Chem. 1994; 269: 7290-7296Abstract Full Text PDF PubMed Google Scholar). Treatment of cell membranes with NO decreases cAMP production by inhibiting calmodulin activation of type I adenylate cyclase, presumably through thiol nitrosylation at the calmodulin-binding site (30Duhe R.J. Nielsen M.D. Dittman A.H. Villacres E.C. Choi E-J. Storm D.R. J. Biol. Chem. 1994; 269: 7290-7296Abstract Full Text PDF PubMed Google Scholar, 31Vorherr T. Knöpfel L. Hofmann F. Mollner S. Pfeuffer T. Carafoli E. Biochemistry. 1993; 32: 6081-6088Crossref PubMed Scopus (139) Google Scholar). Notably, increases in cAMP in leukocytes activate cAMP-dependent protein kinase (PKA). This kinase phosphorylates transcription factors that bind to the cAMP-response element on the TNFα promoter, thereby inhibiting TNFα mRNA transcription (32Economou J.S. Rhoades K. Essner R. Mcbride W.H. Gasson J.C. Morton D.L. J. Exp. Med. 1989; 170: 321-326Crossref PubMed Scopus (99) Google Scholar, 33Newell C.L. Deisseroth A.B. Lopez-Berestein G. J. Leukocyte Biol. 1994; 56: 27-35Crossref PubMed Scopus (116) Google Scholar, 34Righi M. Funct. Neurol. 1993; 8: 359-363PubMed Google Scholar, 35Zhong W.W. Burke P.A. Drotar M.E. Chavali S.R. Frose R.A. Immunology. 1995; 84: 446-452PubMed Google Scholar). The effect of NO on type I adenylate cyclase suggests that NO might up-regulate TNFα synthesis in human monocytes by decreasing cAMP concentrations.We investigated this question using U937 cells, a human monocytic cell line that differentiates into monocyte-macrophage-like cells and produces TNFα when exposed to phorbol myristate acetate (PMA) (36Sundström C. Nilsson K. Int. J. Cancer. 1976; 17: 565-577Crossref PubMed Scopus (1947) Google Scholar, 37Hass R. Lonnemann G. Männel D. Topley N. Hartmann A. Köhler L. Resch K. Goppelt-Strübe M. Leukemia Res. 1991; 15: 327-339Crossref PubMed Scopus (43) Google Scholar, 38Taimi M. Defacque H. Commes T. Favero J. Leukemia Res. 1993; 79: 229-235Google Scholar). The specific objectives were as follows: 1) to demonstrate that NO up-regulates TNFα production in PMA-differentiated U937 cells and test the cGMP-dependence of this effect; 2) to determine whether NO alters resting or stimulated cAMP concentrations in intact cells; 3) to investigate the effect of inhibitors or activators of PKA on NO-stimulated TNFα production in this system; and 4) to determine if NO-induced changes in TNFα mRNA levels were consistent with a cAMP mechanism." @default.
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• W2080931868 title "Nitric Oxide Increases Tumor Necrosis Factor Production in Differentiated U937 Cells by Decreasing Cyclic AMP" @default.
• W2080931868 cites W127742586 @default.
• W2080931868 cites W1420097544 @default.
• W2080931868 cites W1481438484 @default.
• W2080931868 cites W1505955094 @default.
• W2080931868 cites W1511098597 @default.
• W2080931868 cites W1524123582 @default.
• W2080931868 cites W1562045776 @default.
• W2080931868 cites W1580172964 @default.
• W2080931868 cites W1585103813 @default.
• W2080931868 cites W1588379685 @default.
• W2080931868 cites W1611751935 @default.
• W2080931868 cites W1834041853 @default.
• W2080931868 cites W1880336884 @default.
• W2080931868 cites W1963791411 @default.
• W2080931868 cites W1966322594 @default.
• W2080931868 cites W1968713831 @default.
• W2080931868 cites W1979388174 @default.
• W2080931868 cites W1982213879 @default.
• W2080931868 cites W1983880247 @default.
• W2080931868 cites W1986464758 @default.
• W2080931868 cites W1988251156 @default.
• W2080931868 cites W2005205544 @default.
• W2080931868 cites W2011574071 @default.
• W2080931868 cites W2014390290 @default.
• W2080931868 cites W2022699060 @default.
• W2080931868 cites W2024862570 @default.
• W2080931868 cites W2040852689 @default.
• W2080931868 cites W2042519036 @default.
• W2080931868 cites W2042782418 @default.
• W2080931868 cites W2044263892 @default.
• W2080931868 cites W2048635427 @default.
• W2080931868 cites W2048756826 @default.
• W2080931868 cites W2070243129 @default.
• W2080931868 cites W2072818637 @default.
• W2080931868 cites W2074367321 @default.
• W2080931868 cites W2082166614 @default.
• W2080931868 cites W2085327871 @default.
• W2080931868 cites W2085576276 @default.
• W2080931868 cites W2091549165 @default.
• W2080931868 cites W2118477707 @default.
• W2080931868 cites W2120222695 @default.
• W2080931868 cites W2120399350 @default.
• W2080931868 cites W2133764756 @default.
• W2080931868 cites W2140174751 @default.
• W2080931868 cites W2153350360 @default.
• W2080931868 cites W2166389885 @default.
• W2080931868 cites W2237660709 @default.
• W2080931868 cites W2244825722 @default.
• W2080931868 cites W46142867 @default.
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