Plasma Membrane Cholesterol Content Affects Nitric Oxide Diffusion Dynamics and Signaling

Nitric oxide (NO) signaling is inextricably linked to both its physical and chemical properties. Due to its preferentially hydrophobic solubility, NO molecules tend to partition from the aqueous milieu into biological membranes. We hypothesized that plasma membrane ordering provided by cholesterol further couples the physics of NO diffusion with cellular signaling. Fluorescence lifetime quenching studies with pyrene liposome preparations showed that the presence of cholesterol decreased apparent diffusion coefficients of NO ∼20–40%, depending on the phospholipid composition. Electrochemical measurements indicated that the diffusion rate of NO across artificial bilayer membranes were inversely related to cholesterol content. Sterol transport-defective Niemann-Pick type C1 (NPC1) fibroblasts exhibited increased plasma membrane cholesterol content but decreased activation of both intracellular soluble guanylyl cyclase and vasodilator-stimulated phosphoprotein (VASP) phosphorylation at Ser239 induced by exogenous NO exposure relative to their normal human fibroblast (NHF) counterparts. Augmentation of plasma membrane cholesterol in NHF diminished production of both cGMP and VASP phosphorylation elicited by NO to NPC1-comparable levels. Conversely, decreasing membrane cholesterol in NPC1 resulted in the augmentation in both cGMP and VASP phosphorylation to a level similar to those observed in NHF. Increasing plasma membrane cholesterol contents in NHF, platelets, erythrocytes and tumor cells also resulted in an increased level of extracellular diaminofluorescein nitrosation following NO exposure. These findings suggest that the impact of cholesterol on membrane fluidity and microdomain structure contributes to the spatial heterogeneity of NO diffusion and signaling. Nitric oxide (NO) signaling is inextricably linked to both its physical and chemical properties. Due to its preferentially hydrophobic solubility, NO molecules tend to partition from the aqueous milieu into biological membranes. We hypothesized that plasma membrane ordering provided by cholesterol further couples the physics of NO diffusion with cellular signaling. Fluorescence lifetime quenching studies with pyrene liposome preparations showed that the presence of cholesterol decreased apparent diffusion coefficients of NO ∼20–40%, depending on the phospholipid composition. Electrochemical measurements indicated that the diffusion rate of NO across artificial bilayer membranes were inversely related to cholesterol content. Sterol transport-defective Niemann-Pick type C1 (NPC1) fibroblasts exhibited increased plasma membrane cholesterol content but decreased activation of both intracellular soluble guanylyl cyclase and vasodilator-stimulated phosphoprotein (VASP) phosphorylation at Ser239 induced by exogenous NO exposure relative to their normal human fibroblast (NHF) counterparts. Augmentation of plasma membrane cholesterol in NHF diminished production of both cGMP and VASP phosphorylation elicited by NO to NPC1-comparable levels. Conversely, decreasing membrane cholesterol in NPC1 resulted in the augmentation in both cGMP and VASP phosphorylation to a level similar to those observed in NHF. Increasing plasma membrane cholesterol contents in NHF, platelets, erythrocytes and tumor cells also resulted in an increased level of extracellular diaminofluorescein nitrosation following NO exposure. These findings suggest that the impact of cholesterol on membrane fluidity and microdomain structure contributes to the spatial heterogeneity of NO diffusion and signaling. As a small sized gaseous free radical, nitric oxide (NO) 2The abbreviations used are: NO, nitric oxide; cGC, guanylate cyclase; DAF, diaminofluorescein; DEA/NO, 2-(N,N-diethylamino)-diazenolate-2-oxide diethylammonium salt; DPPC, dipalmitoylphosphatidyl choline; DMPC, dimyristoylphosphatidyl choline; DPTA, diethylenetriaminepentaacetic acid; BLM, bilayer lipid membrane; MβCD, methyl-β-cyclodextrin; Mn(III)TMPyP, Mn(III)tetrakis(1-methyl-4-pyridyl) porphyrin pentachloride; NPC1, Niemann-Pick type C1; NHF, normal human fibroblast(s); PBS, phosphate-buffered saline; PFO-D4, perfringolysin-O domain 4; VASP, vasodilator-stimulated phosphoprotein; phospho-VASP, serine 239-phosphorylated VASP; CHAPS, 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonic acid; SV, Stern-Volmer. 2The abbreviations used are: NO, nitric oxide; cGC, guanylate cyclase; DAF, diaminofluorescein; DEA/NO, 2-(N,N-diethylamino)-diazenolate-2-oxide diethylammonium salt; DPPC, dipalmitoylphosphatidyl choline; DMPC, dimyristoylphosphatidyl choline; DPTA, diethylenetriaminepentaacetic acid; BLM, bilayer lipid membrane; MβCD, methyl-β-cyclodextrin; Mn(III)TMPyP, Mn(III)tetrakis(1-methyl-4-pyridyl) porphyrin pentachloride; NPC1, Niemann-Pick type C1; NHF, normal human fibroblast(s); PBS, phosphate-buffered saline; PFO-D4, perfringolysin-O domain 4; VASP, vasodilator-stimulated phosphoprotein; phospho-VASP, serine 239-phosphorylated VASP; CHAPS, 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonic acid; SV, Stern-Volmer. presents unique challenges toward understanding the nature of its signaling in biological systems. Numerous levels of regulation at the level of nitric oxide synthase catalysis influence the rate of NO generation. Spatial localization of the biological signal is secondarily determined by a combination of the distinct physical and chemical properties of NO within the context of the microenvironment in which it was formed. The lifetime of NO molecules is governed chiefly by their relative abundance in relation to other radicals (1Issner R. Nauser T. Bugnon P. Lye P.G. Koppenol W.H. Chem. Res. Toxicol. 1997; 10: 1285-1292Crossref PubMed Scopus (563) Google Scholar, 2Lima E.S. Di Mascio P. Abdalla D.S. J. Lipid Res. 2003; 44: 1660-1666Abstract Full Text Full Text PDF PubMed Scopus (63) Google Scholar), transition metal centers (3Chiang C.Y. Darensbourg M.Y. J. Biol. Inorg. Chem. 2006; 11: 359-370Crossref PubMed Scopus (40) Google Scholar, 4Mason M.G. Nicholls P. Wilson M.T. Cooper C.E. Proc. Natl. Acad. Sci. U. S. A. 2006; 103: 708-713Crossref PubMed Scopus (189) Google Scholar), and oxygen (O2) (5Caccia S. Denisov I. Perrella M. Biophys. Chem. 1999; 76: 63-72Crossref PubMed Scopus (15) Google Scholar, 6Lewis R.S. Deen W.M. Chem. Res. Toxicol. 1994; 7: 568-574Crossref PubMed Scopus (244) Google Scholar). In addition to its very small size, the diffusional path of NO from the point of origin is affected by its preferentially hydrophobic solubility (7Wood J. Garthwaite J. Neuropharmacology. 1994; 33: 1235-1244Crossref PubMed Scopus (418) Google Scholar, 8Philippides A. Husbands P. O'Shea M. J. Neurosci. 2000; 20: 1199-1207Crossref PubMed Google Scholar), resulting in an enrichment of NO in biological membranes relative to the aqueous milieu. In the present work, the hypothesis that cells may utilize plasma membrane cholesterol to further orchestrate spatial heterogeneity in NO biological signaling activity was tested. Cholesterol, a major lipid component of the plasma membrane in eukaryotic cells, plays an essential role in maintaining membrane fluidity and architecture (9Pucadyil T.J. Chattopadhyay A. Chem. Phys. Lipids. 2006; 143: 11-21Crossref PubMed Scopus (30) Google Scholar, 10Hao M. Mukherjee S. Maxfield F.R. Proc. Natl. Acad. Sci. U. S. A. 2001; 98: 13072-13077Crossref PubMed Scopus (251) Google Scholar, 11Rukmini R. Rawat S.S. Biswas S.C. Chattopadhyay A. Biophys. J. 2001; 81: 2122-2134Abstract Full Text Full Text PDF PubMed Scopus (85) Google Scholar). Cells tightly control the ratio of cholesterol and phospholipids in membranes to best suit their biological functions. Within the plasma membrane, cholesterol segregated with sphingolipids and selective proteins form distinct lipid raft complexes that act as ordered platforms for communicating signals into and out of cells (12Simons K. Ikonen E. Nature. 1997; 387: 569-572Crossref PubMed Scopus (8090) Google Scholar). Dysregulation of cholesterol synthesis and transport acts as a contributing factor to pathophysiological changes (13Preston Mason R. Tulenko T.N. Jacob R.F. Biochim. Biophys. Acta. 2003; 1610: 198-207Crossref PubMed Scopus (97) Google Scholar, 14Chen M. Mason R.P. Tulenko T.N. Biochim. Biophys. Acta. 1995; 1272: 101-112Crossref PubMed Scopus (71) Google Scholar, 15Qin C. Nagao T. Grosheva I. Maxfield F.R. Pierini L.M. Arterioscler. Thromb. Vasc. Biol. 2006; 26: 372-378Crossref PubMed Scopus (75) Google Scholar, 16Vainio S. Bykov I. Hermansson M. Jokitalo E. Somerharju P. Ikonen E. Biochem. J. 2005; 391: 465-472Crossref PubMed Scopus (52) Google Scholar, 17Koike T. Ishida G. Taniguchi M. Higaki K. Ayaki Y. Saito M. Sakakihara Y. Iwamori M. Ohno K. Biochim. Biophys. Acta. 1998; 1406: 327-335Crossref PubMed Scopus (60) Google Scholar), which are of particular importance in cardiovascular disease, chronic inflammation, and lipid disorders such as Niemann-Pick disease. The influence of cholesterol on NO diffusion was directly quantified in liposomal and artificial bilayer preparations. Soluble guanylyl cyclase (sGC) activation, VASP phosphorylation (Ser239), and extracellular diaminofluorescein (DAF) nitrosation were used to investigate the of cellular plasma membrane cholesterol content on NO signaling that plasma membrane cholesterol content the level and type of NO in levels and of cellular cholesterol may a of NO signaling. diaminofluorescein and were from and the cholesterol were from was from Mn(III)tetrakis(1-methyl-4-pyridyl) porphyrin was from The cGMP was from NO with was by and used directly for in with and quantified by a as M. P. M. C. R. G. J. Biol. Chem. 2006; Full Text Full Text PDF PubMed Scopus Google Scholar). human fibroblasts and cells were from and NPC1 fibroblasts were from the Cells were in essential with and at an of and were from by as NO by of of pyrene with such as NO and are The of and used to the diffusion of nitric oxide in hydrophobic of apparent diffusion coefficients A. R. E. Biochem. Biophys. PubMed Scopus Google Scholar, A. C. E. R. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus (75) Google Scholar, M. C. R. A. J. Biol. Chem. 2005; Full Text Full Text PDF PubMed Scopus Google Scholar). We of in the presence of cholesterol with as nitric oxide from a was into liposome in to quenching in a were with a and NO was determined by an and with a were by the quenching observed the for with a of were determined from the of and for and and in and in P.G. J. Biol. Chem. 1995; Full Text Full Text PDF PubMed Scopus Google Scholar). coefficients were from the A. R. E. Biochem. Biophys. PubMed Scopus Google Scholar), the of the The of and is and used to membrane the A. Scopus Google Scholar). NO in a was from The of were in in a with a and with of was and on the in the in the of the were with at a rate of The was at and both of the were with the of The of the lipid bilayer was by the of and by of NO was out with a and to of the The of NO the was with an NO as a of and and of the was used to the the of the The the was as the and into the it the and on the of the the The used were as was on a with in was with in and and was to by on a and with a of at from on a and the of was as the ratio of to of was with cholesterol as J. Lipid Res. 1997; Full Text PDF PubMed Google Scholar). of cholesterol was by with In of cells in were with on the of cholesterol by for with cellular cholesterol cholesterol cells in were with for cholesterol for at with cellular were and cells were used for of with on were for at with in and with for with Cells were and on an with exposure were and the of was for cells from of and of cells of at were and with and with and of was by in a was by and the was at for of plasma membrane was as S. Bykov I. Hermansson M. Jokitalo E. Somerharju P. Ikonen E. Biochem. J. 2005; 391: 465-472Crossref PubMed Scopus (52) Google Scholar). Lipid in was with of and with and the was in a a of of of from lipid was into for by were to a membrane and with to and by with to The were with a was in of and for at of the were with and and the was at J. 2005; PubMed Scopus Google Scholar). was from a and phospholipid cells was by the following was in of and cholesterol was quantified a cholesterol and from a In cholesterol is by cholesterol to the as a production of is to the of to the by was to the to in a at with an of on a cGMP and VASP as of NO were to and with for to NO The cells were a further with the and to the NO and and for in the Cells were with and for the cells were and with and The were for cGMP with an VASP and by with VASP and of by and to of was also by the of extracellular with NO by exogenous NO in the presence of Cells are of as and a of NO from an extracellular its with a such as the of intracellular which to signals U. M. A. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar, E. Garthwaite J. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar, Garthwaite J. Biochem. PubMed Scopus Google Scholar). NHF and fibroblasts and cells were and with and in cells and were from by and in Cells were to a of in a and were to of NO the addition of cholesterol was as indicated following was by a to in cholesterol was and cells were in a in and with the for of in the of a with at an of of in pyrene and such as NO and are The of and used to apparent diffusion coefficients of NO in hydrophobic A. R. E. Biochem. Biophys. PubMed Scopus Google Scholar, A. C. E. R. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus (75) Google Scholar, M. C. R. A. J. Biol. Chem. 2005; Full Text Full Text PDF PubMed Scopus Google Scholar). of pyrene with dipalmitoylphosphatidyl and dimyristoylphosphatidyl were to NO in NO diffusion into the liposome was by quenching of pyrene These were as a the quenching from was the of NO and The addition of cholesterol to resulted in a and in the of a in NO with pyrene within the lipid The quenching for liposome was determined by the for by the lifetime for liposome diffusion coefficients for NO were from the A. Scopus Google Scholar). These indicated that the presence of cholesterol in and the diffusion by and a influence of cholesterol the diffusion of NO in a liposome of cholesterol on the diffusion coefficients and membrane in a of NO across Lipid as a of Increasing was used to directly the cholesterol content and the rate of NO diffusion an artificial bilayer membrane of was on a in the phosphate-buffered The signal the of NO into the the a membrane diffusion rate of of decreased with of cholesterol to of the at bilayer cholesterol content. The of may to in membrane structure induced by cholesterol the of cholesterol in the provided that NO membranes decreased as a of cholesterol content. Niemann-Pick and as a for fibroblasts to a in plasma membrane cholesterol content S. Bykov I. Hermansson M. Jokitalo E. Somerharju P. Ikonen E. Biochem. J. 2005; 391: 465-472Crossref PubMed Scopus (52) Google and decreased membrane fluidity relative to normal human fibroblasts S. Bykov I. Hermansson M. Jokitalo E. Somerharju P. Ikonen E. Biochem. J. 2005; 391: 465-472Crossref PubMed Scopus (52) Google Scholar, 17Koike T. Ishida G. Taniguchi M. Higaki K. Ayaki Y. Saito M. Sakakihara Y. Iwamori M. Ohno K. Biochim. Biophys. Acta. 1998; 1406: 327-335Crossref PubMed Scopus (60) Google Scholar). with plasma membranes from NPC1 fibroblasts were to cholesterol content relative to NHF, a similar level of proteins and phospholipid content was present in both of cells with domain that to lipid raft Y. Y. M. M. M. M. S. 10: PubMed Scopus Google In to the of NHF, NPC1 fibroblasts exhibited a across the of the plasma In with the plasma membrane of was on NPC1 fibroblasts relative to NHF is a that a cholesterol with the plasma membrane P.G. J. Biol. Chem. 1995; Full Text Full Text PDF PubMed Scopus Google Scholar, J. Lipid Res. 1997; Full Text PDF PubMed Google Scholar). The to the cholesterol of both NHF and NPC1 fibroblasts with was by and on NHF to increased in and NHF that resulted in a in plasma membrane The was with NPC1 fibroblasts resulting in a in and the for NO of Soluble and the of NHF and NPC1 fibroblast was used to the hypothesis that cholesterol levels in cellular plasma membranes NO signaling of intracellular of was as a for changes in the level of extracellular NO diffusion the plasma The from activity was by the presence of the The levels of cGMP that in to exogenous and were and in NPC1 fibroblasts in with that observed in an of NHF NHF were with to plasma membrane cholesterol to production of cGMP elicited by exposure was similar to NPC1 fibroblast to decreased NHF cGMP levels and following In the decreasing the plasma membrane in NPC1 by increased cGMP production by and in to and DEA/NO, In the plasma membrane was by cellular to NPC1 and of the cGMP by NHF These the hypothesis that plasma membrane cholesterol levels the of activation by These were to in plasma membrane cholesterol affected signaling. VASP is an that is a for both and J. 2005; PubMed Scopus Google Scholar, U. M. A. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar, E. Garthwaite J. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar, Garthwaite J. Biochem. PubMed Scopus Google Scholar, Y. Y. M. M. M. M. S. 10: PubMed Scopus Google Scholar, M.G. J. Biol. Chem. 2001; Full Text Full Text PDF PubMed Scopus Google Scholar, M.G. Proc. Natl. Acad. Sci. U. S. A. PubMed Scopus Google Scholar, M. Res. PubMed Scopus Google Scholar, S. J. PubMed Scopus Google Scholar). with cGMP VASP in NPC1 cells to was levels observed in an of NHF of plasma membrane cholesterol from NPC1 cells with resulted in a in VASP following NO exposure. Conversely, augmentation of plasma membrane cholesterol in NHF with resulted in the VASP phosphorylation by and These that plasma membrane cholesterol content influence NO with intracellular such as signaling and VASP of plasma membrane cholesterol and intracellular NO was We that levels of membrane cholesterol in an increased abundance of NO in the extracellular of the the of were to NO in the presence of extracellular M.G. J. Biol. Chem. 2001; Full Text Full Text PDF PubMed Scopus Google Scholar), and the of was The of following the addition of exogenous NO to in the presence of NHF NPC1 fibroblasts is in These indicated a level of extracellular nitrosation elicited by NO in the presence of NPC1 fibroblasts with NHF. nitrosation was increased NHF cells were with and to NO exposure of extracellular nitrosation was observed with relative to control cells NO exposure In the of NPC1 plasma membrane cholesterol by in cholesterol by and in resulted in a in following NO exposure changes in the NO and the of and M.G. Proc. Natl. Acad. Sci. U. S. A. PubMed Scopus Google Scholar). were to was by cellular of the porphyrin the nitrosation for in the in the presence of cells relative to their counterparts. the hypothesis that increased plasma membrane cholesterol levels NO into the a level of NO and nitrosation of present in the extracellular from liposome and artificial showed that increased cholesterol diffusion of NO lipid membranes and NHF and NPC1 fibroblasts was to plasma membrane cholesterol influence on NO signaling in cells changes in NO signaling in NHF NPC1 fibroblasts by decreasing membrane cholesterol levels. The of was to investigate plasma membrane cholesterol levels NO diffusion and cellular signaling. NO is to the plasma membrane M. Res. PubMed Scopus Google and an to with such as of membrane cholesterol content. from with liposomal membranes with pyrene molecules that NO diffusion were inversely related to cholesterol content in the NO diffusion was observed with cholesterol in with liposome of phospholipid which the of S. J. PubMed Scopus Google Scholar). as as cholesterol was to the diffusion rate of NO the cholesterol to resulted in a in diffusion The of diffusion the of a to its Due to the very small of NO in with NO is to membrane A. PubMed Scopus Google Scholar). in the physical of membranes by cholesterol to in of cholesterol with phospholipid A. Proc. Natl. Acad. Sci. U. S. A. 2005; PubMed Scopus Google Scholar). of ordered complexes a in membrane to a tightly spatial in the membrane milieu may for of NO in relation to increased cholesterol and from the that NO diffusion was to changes in and membrane by the of from liposome and the that cholesterol levels in cellular membranes may a impact on NO and signaling. Niemann-Pick C1 is an by cholesterol to NPC1 M. A. M. E. P.G. Proc. Natl. Acad. Sci. U. S. A. 2001; 98: PubMed Scopus Google Scholar). of NPC1 fibroblasts increased levels of plasma membrane cholesterol and lipid relative to NHF In of the cGMP levels elicited in NPC1 fibroblasts to NO were that observed in their NHF enrichment of NHF plasma membrane cholesterol by with resulted in a similar in cGMP elicited by NO with NHF with cholesterol Conversely, the of plasma membrane cholesterol from NPC1 fibroblasts resulted in an in the of cGMP to NO by both NPC1 cells and NHF were within of other plasma membranes were to NO exposure. These are with a diminished of exogenous NO molecules to cellular plasma membranes as a of increased cholesterol which was directly related to the activation of intracellular in membrane cholesterol were to influence of such as the VASP, a of and U. M. A. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar, E. Garthwaite J. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar, Garthwaite J. Biochem. PubMed Scopus Google Scholar, Y. Y. M. M. M. M. S. 10: PubMed Scopus Google Scholar, M.G. J. Biol. Chem. 2001; Full Text Full Text PDF PubMed Scopus Google Scholar, M.G. Proc. Natl. Acad. Sci. U. S. A. PubMed Scopus Google Scholar, M. Res. PubMed Scopus Google Scholar, S. J. PubMed Scopus Google Scholar, A. PubMed Scopus Google Scholar, A. Proc. Natl. Acad. Sci. U. S. A. 2005; PubMed Scopus Google Scholar, M. A. M. E. P.G. Proc. Natl. Acad. Sci. U. S. A. 2001; 98: PubMed Scopus Google Scholar, M. Biol. 2003; PubMed Scopus Google Scholar, M. J. Sci. PubMed Scopus Google Scholar, M. Cooper Full Text Full Text PDF PubMed Scopus Google Scholar, Biol. 2003; Full Text Full Text PDF PubMed Scopus Google Scholar, Arterioscler. Thromb. Vasc. Biol. 2000; 20: PubMed Scopus Google Scholar, S. S. I. M. K. J. C. I. U. U. M. 103: PubMed Scopus Google Scholar, G. K. M. U. Arterioscler. Thromb. Vasc. Biol. PubMed Scopus Google Scholar, A. A. M. M. S. R. J. 1999; PubMed Scopus Google Scholar). that the level of VASP phosphorylation elicited by NO exposure by augmentation of plasma membrane These suggest that may signaling The spatial heterogeneity that cholesterol to the plasma membrane may act to at levels. with plasma membrane with cholesterol M. P. M. C. R. G. J. Biol. Chem. 2006; Full Text Full Text PDF PubMed Scopus Google Scholar, J. 2005; PubMed Scopus Google Scholar, U. C. P. P. A. P. P. U. Biol. PubMed Scopus Google Scholar). Due to the of to NO in the E. Garthwaite J. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar, Garthwaite J. Biochem. PubMed Scopus Google Scholar), small in NO the membrane by cholesterol act to the for In and U. C. P. P. A. P. P. U. Biol. PubMed Scopus Google that exhibited an to levels of NO, activity in to levels of NO was decreased in the membrane with the In with cholesterol of by and and by J. 2005; PubMed Scopus Google Scholar). These studies and the present that plasma membrane cholesterol is linked to with the and of its determined by unique to and activation In addition to the for activation, the that of plasma membrane cholesterol of NO was to the chemical for NO in the extracellular of NO is that the oxide and biological the context of the in which catalysis M.G. Proc. Natl. Acad. Sci. U. S. A. PubMed Scopus Google Scholar, M.G. S. Y. Acad. Sci. PubMed Scopus Google Scholar). The findings showed that membrane cholesterol was inversely related to NO that increased plasma membrane cholesterol the chemical for NO in the extracellular The rate of NO is related to the of NO an increased abundance of NO of of the R.S. Deen W.M. Chem. Res. Toxicol. 1994; 7: 568-574Crossref PubMed Scopus (244) Google Scholar, M.G. Proc. Natl. Acad. Sci. U. S. A. PubMed Scopus Google Scholar, Chem. Res. Toxicol. PubMed Scopus Google Scholar). NPC1 fibroblasts with plasma membrane cholesterol an increased nitrosation of extracellular NO exposure relative to NHF were plasma membrane cholesterol was in NPC1 and NHF cells, in extracellular nitrosation was also observed with NO exposure relative to control These suggest that increased plasma membrane cholesterol content may influence the biological of catalysis and signaling by the from intracellular of such as to of and nitrosation of extracellular In of to may the from to act as a to diffusion in membranes A. Proc. Natl. Acad. Sci. U. S. A. PubMed Scopus Google as as a in in cellular J. E. 2003; PubMed Scopus Google Scholar). cholesterol on were a component in NO is with to and were in an The that cholesterol in cells may in of depending on its ratio to NO, for the of M.G. Proc. Natl. Acad. Sci. U. S. A. PubMed Scopus Google Scholar), was into in were observed with and of the oxide in cellular out a of to the is a factor in a of the that may by cholesterol at the level of the architecture and its resulting in diminished NO NO signaling G. M. Proc. Natl. Acad. Sci. U. S. A. 2001; 98: PubMed Scopus Google Scholar), the that cholesterol and NO also directly at the physical chemical level in the plasma is to that the in the of NO signals in NPC1 fibroblasts from intracellular toward extracellular nitrosation by cholesterol cells utilize the ordering of cholesterol to spatial control NO signaling at the membrane microdomain level a point for further studies by and J. Biochem. PubMed Scopus Google Scholar, 2005; Full Text Full Text PDF PubMed Scopus (85) Google Scholar, J. J. 2005; PubMed Scopus Google Scholar, M. J. 2006; PubMed Scopus Google that membrane lipid raft in cells is related to the of raft cholesterol by increased the of cells to The were with of membrane cholesterol with J. Biochem. PubMed Scopus Google Scholar, 2005; Full Text Full Text PDF PubMed Scopus (85) Google Scholar, J. J. 2005; PubMed Scopus Google Scholar, M. J. 2006; PubMed Scopus Google Scholar). of the signaling are J. Di K. Res. PubMed Scopus Google with G. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google as a of the signaling in cholesterol and are in the and of Y. T. T. J. 11: PubMed Scopus Google Scholar, J. M. A. T. PubMed Scopus Google Scholar, Res. PubMed Scopus Google Scholar, G. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar). findings that increased plasma membrane cholesterol content the for exogenous NO to and the VASP the that the physical of NO by membrane cholesterol a contributing factor in the of and cardiovascular The present findings in both and indicated that membrane cholesterol the physical and cellular signaling of

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