High Density Lipoproteins Enhance the Na⁺/H⁺ Antiport in Human Platelets

Summary

In the present study, we investigated the effect of high density lipoproteins 3 (HDL₃) on Na⁺/H⁺ exchanger activity and cytosolic pH (pH_i) in human platelets. HDL₃ alone failed to affect pHi? but preincubation with HDL₃ significantly enhanced the Na⁺/H⁺ antiport activation brought about by acidification with 100 mM sodium propionate or stimulation with 0.05 U/ml thrombin. The stimulatory effect of HDL₃ was unaffected by indomethacin excluding a role for cyclooxygenase products. The HDL₃ effect was not mediated by Ca²⁺/calmodulin-dependent protein kinase as HDL₃ failed to increase cytosolic free calcium concentration. However, the potentiating effect of HDL₃ was completely blocked in the presence of the protein kinase C inhibitor, bisindoylmaleimide and the phosphatidylcholine-specific phospholi-pase C inhibitor, D609. Furthermore, the effect of HDL₃ was abolished after covalent modification of HDL₃ with dimethylsuberimidate and was not observed in platelets from Glanzmann thrombasthenia type 1 which do not express GP IIb/IIIa, as well as in platelets preincubated with anti-GP Ilb/IIIa polyclonal antibodies. We conclude that HDL₃ enhances the sodium propionate- and thrombin-induced Na⁺/H⁺ antiport activity in human platelets via binding to GP Ilb/IIIa and activation of protein kinase C and phosphatidylcholine-specific phospholipase C.

• References

• 1 Gordon T, Rifkind BM. High density lipoproteins - the clinical implication of recent studies. N Engl J Med 1989; 321: 1311-1315
• 2 Assmann G, von Eckardstein A, Funke H. High density lipoproteins, Reverse transport of cholesterol, and coronary artery disease: Insights from mutations. Circulation 1993; 87 (Suppl. 03) III28-III34
• 3 Suria I, Akkermann J-WN. The influence of lipoproteins on blood platelets. Am Heart J 1992; 125: 272-275
• 4 Bierenbaum ML, Fleischmann AI, Stier A, Watson P, Somol H, Naso AM, Binder M. Increased platelet aggregation and decreased high-density lipoprotein cholesterol in women on oral contraceptives. Am J Obstet Gynecol 1979; 134: 638-641
• 5 Aviram M, Brook G. Characterization of the effect of plasma lipoproteins on platelet function in vitro. Haemostasis 1983; 13: 344-350
• 6 Aviram M, Brook G. Platelet interaction with high and low density lipoproteins. Atherosclerosis 1983; 46: 259-268
• 7 Higashihara M, Kinoshita M, Shoji K, Teramoto T, Kurokawa K. Inhibition of platelet function by high density lipoprotein from a patient with apolipo-protein E deficiency. Biochem Biophys Res Commun 1991; 181: 1331-1336
• 8 Beitz J, Mest H-J. Thromboxane A2 (TxA2) formation by washed platelets under the influence of low and high density lipoproteins. Prostaglandins Leukotriens Med 1986; 23: 303
• 9 Beitz H, Kuklinski B, Taube Ch, Mest H-J. Influence of plasma fraction of human blood rich in high density lipoproteins on the in vitro formation of prostaglandin I2 (PGI2) and thromboxane A2 (TxA2). Prostaglandins Leukotriens and Essential Fatty Acids 1989; 35: 37-40
• 10 Virgolini I, Li tS, Yang Q, Banyai M, Koller E, Angelberger P, Sinzinger H. Binding of 11’In-labeled HDL to platelets from normolipemic volunteers and patients with heterozygous familial hypercholesterolemia. Arteriosclerosis Thromb 1992; 12: 849-861
• 11 Curtiss LK, Plow EF. Interaction of plasma lipoprotein with human platelets. Blood 1984; 64: 365-374
• 12 Koller E, Koller F, Doelschel W. Specific binding sites on human blood platelets for plasma lipoproteins. Hoppe-Seyler’s Z Physiol Chem 1982; 363: 395-405
• 13 Koller E, Koller F, Binder VR. Purification and identification of the lipoprotein binding proteins from human blood platelet membranes. J Biol Chem 1989; 264: 12412-12418
• 14 Nofer J-R, Walter M, Seedorf U, Assmann G. HDL3 modulate platelet aggregation by activation of protein kinase C. Circulation (Suppl.) 1993; 8: 457
• 15 Nazih H, Nazih-Sanderson F, Magret V, Caron B, Goudemend J, Fruchart JC, Delbart C. Protein kinase C-dependent desensitization of HDL3 activated phospholipase C in human platelets. Arteriosclerosis Thromb 1994; 14: 1321-1326
• 16 Nazih H, Devred D, Martin-Nizard F, Fruchart JC, Delbart C. Phosphatidylcholine breakdown in HDL3 stimulated platelets. Thromb Res 1990; 59: 913-920
• 17 Nazih H, Devred D, Martin-Nizard F, Clavey V, Fruchart JC, Delbart C. Pertussis toxin sensitive G-protein coupling of HDL receptor to phospholipase C in human platelets. Thromb Res 1992; 67: 559-567
• 18 Nofer J-R, Walter M, Kehrel B, Seedorf U, Assmann G. HDL3 activates phospholipase D in normal but not in glycoprotein IMIIa-deficient platelets. Biochem Biophys Res Comm 1995; 207: 148-154
• 19 Siffert W. Regulation of platelet function by sodium hydrogen exchange. Cardiovasc Res 1995; 29: 160-166
• 20 Steiner B, Cousot D, Trzeciak A, Gillesen D, Hadvary P. Ca2+-dependent binding of a synthetic peptide Arg-Gly-Asp (RGD) to a single site on the purified platelet glycoprotein IMIIa-complex. J Biol Chem 1989; 264: 13102-13108
• 21 Havel RJ, Eder H, Bragdon JH. The distribution and chemical composition of ultracentrifugally separated lipoproteins in human serum. J Clin Invest 1995; 3: 1345-1353
• 22 Lowry OH, Rosebrough NJ, Farn AL, Randall RJ. Protein measurement with Folin phenol reagent. J Biol Chem 1951; 193: 265-275
• 23 Chaco GK, Mahlberg FH, Johnson WJ. Cross-linking of apoproteins in high density lipoproteins by dimethylsuberimidate inhibits specific lipoprotein binding to membranes. J Lipid Res 1988; 28: 319-327
• 24 Thomas JA, Buchsbaum RN, Zimniak A, Racker E. Intracellular pH measurements in Ehrlich ascites tumor cells utilizing spectroscopic probes generated in situ. Biochemistry 1979; 81: 2210-2218
• 25 Rosskopf D, Siffert G, Osswald U, Witte K, Diising R, Akkerman J-WN, Siffert W. Platelet Na+-H+ exchanger activity in normotensive and hypertensive subjects: effect of enalapril therapy upon antiport activity. J Hyper-tens 1992; 10: 839-847
• 26 Tepel M, Kiihnapfel S, Theilmeier G, Teupe C, Schlotman R, Zidek W. Filling state of intracellular Ca2+ pools triggers trans-plasma membrane Na+ and Ca2+ influx by a tyrosine kinase dependent pathway. J Biol Chem 1994; 269: 26239-26242
• 27 Tepel M, Wischniowski H, Zidek W. Thapsigargin-induced [Ca2+]j increase activates sodium influx in human platelets. Biochem Biophys Acta 1994; 1220: 248-252
• 28 Grynkiewicz G, Poenie M, Tsien RY. A new generation of Ca2+ indicators with greatly improved fluorescence properties. J Biol Chem 1985; 260: 3440-3450
• 29 Borin M, Siffert W. Further characterisation of the mechanisms mediating the rise in cytosolic free Na+ in thrombin-stimulated platelets. Evidence for the inhibition of the Na+, K+ATP-ase and for Na+ entry via Ca2+ influx pathway. J Biol Chem 1991; 266: 13153-13160
• 30 Stamouli V, Vakirtzi-Lemonias C, Siffert W. Thrombin and NaF, but not epinephrine raise cytosolic free Na+ in human platelets. Biochem Biophys Acta 1993; 1176: 215-221
• 31 Kilsdonk EPC, van Gent T, Dorsman ANRD, van Tol A. Binding of modified high density lipoproteins to endothelial cells: relation with cellular cholesterol efflux?. Atherosclerosis 1992; 97: 131-142
• 32 Andrews HE, Aitken JW, Hassal DG, Skinner VO, Bruckdorfer KR. Intracellular mechanisms in the activation of human platelets by low-density lipoproteins. Biochem J 1987; 242: 559-564
• 33 Grinstein S, Cohen S, Goetz JD, Rothstein A, Gelfand EW. Characterization of the activation of Na+/H+ exchange in lymphocyte by phorbol esters: Change in cytoplasmic pH dependence of the antiport. Proc Natl Acad Sci USA 1985; 82: 1429-1433
• 34 Bertrand B, Wakabayshi S, Ikeda T, Pouyssegur J, Shikegawa M. The Na+/H+-exchanger isoform 1 (HNE 1) is a novel member of calmodulin-binding proteins. Identification and characterization of calmodulin-binding sites. J Biol Chem 1994; 269: 13703-13709
• 35 dWakabayshi S, Bertrand B, Ikeda T, Pouyssegur J, Shikegawa M. Mutation of calmodulin-binding sites renders the Na+/H+-exchanger (HNE 1) highly H+-sensitive and Ca2+-regulation defective. J Biol Chem 1994; 269: 13703-13709
• 36 Kimura M, Gardner JP, Aviv A. Agonist-evoked alkaline shift in the cytosolic pH set-point for activation of platelets. The role of cytosolic Ca2+ and protein kinase C. J Biol Chem 1990; 265: 21068-21074
• 37 Siffert W, Akkermann J-WN. Protein kinase C enhances Ca2+ mobilization in human platelets by activating Na+/H+ exchange. J Biol Chem 1988; 263: 4223-4227
• 38 Noel J, Pouyssegur J. Hormonal regulation, pharmacology, and membrane sorting of vertebrate Na+/H+-exchanger isoforms. Am J Physiol 1995; 268: C283-C296
• 39 Kroll MH, Schafer AI. Biochemical mechanisms of platelet activation. Blood 1989; 74: 1181-1190
• 40 Mendez AJ, Oram JF, Bierman EL. Protein kinase C as a mediator of high density lipoprotein receptor-dependent efflux of intracellular cholesterol. J Biol Chem 1991; 266: 10104-10111
• 41 Theret N, Delbart C, Aguie G, Fruchart JC, Vassaux G, Ailhaud G. Cholesterol efflux from adipose cells is coupled to diacylglycerol production and protein kinase C activation. Biochem Biophys Res Comm 1990; 173: 1361-1368
• 42 Walter M, Reinecke H, Nofer J-R, Seedorf U, Assmann G. HDL3 stimulates multiple signalling pathways in human fibroblasts. Arterioscler Thromb and Vase Biol 1995; 15: 1975-1986
• 43 Krishnamurthi S, Patel Y, Morgan WA, Wheeler-Jones CP, Kakkar VV. Na+/H+ exchange is not necessary for protein kinase C-mediated effects in platelets. FEBS Lett 1989; 252: 147-152
• 44 Krishnamurthi S, Morgan WA, Kakkar VV. Extracellular Na+ removal enhances granule secretion in platelets - evidence that Na+-H+ exchange is inhibitory to secretion induced by some agonists. FEBS Lett 1989; 250: 195-200
• 45 Krishnamurthi S, Morgan WA, Kakkar VV. Extracellular Na+, but not Na+/H+ exchange, is necessary for receptor-mediated arachidonate release in platelets. Biochem J 1990; 265: 155-160
• 46 Sage OS, Rink T. Effects of ionic substitution on [Ca2+]j rises evoked by thrombin and PAF in human platelets. Europ J Pharm 1986; 128: 99-107
• 47 Sanchez A, Alonso MT, Collazos JM. Thrombin-induced changes in intracellular [Ca2+] and pH in human platelets. Cytoplasmic alkalinization is not prerequisite for calcium mobilization. Biochem Biophys Acta 1988; 938: 497-500
• 48 Davies TA, Weil GJ, Simons ER. Simultaneous flow cytometric measurements of thrombin-induced cytosolic pH and Ca2+ fluxes in human platelets. J Biol Chem 1990; 11522-11526