Skip to main content
Log in

Studies on the selectivity of enzymes involved in platelet-activating factor formation in stimulated cells

  • PAF Metabolism and Its Regulation
  • Published:
Lipids

Abstract

The present studies were undertaken to obtain further insight into the selectivities of the enzymes, i.e., phospholipase A2 and acetyltransferase, involved in platelet-activating factor (PAF) production upon stimulation of human polymorphonuclear leukocytes (PMN) and platelets. After appropriate stimulation of the cells in the presence of [3H]acetate the total PAF and analogs, i.e., 1-alkyl-2-acetyl-, 1-alkenyl-2-acetyl-, and 1-acyl-2-acetyl-glycero-3-phosphocholine were isolated by high performance liquid chromatography. The isolated mixture was subjected to treatment with phospholipase A1 to differentiate acetate incorporation into 1-ether linked and 1-ester linked species. The ratio of acetate incorporation into 1-ether linked vs 1-ester linked PAF analogs amounted to 13.8±1.0 and 1.3±0.1 for PMN and platelets, respectively. When compared to the ratio of 1-ether linked and 1-ester linked species in the diradylglycerophosphocholine precursors in each cell type, i.e., 1.13 for PMN and 0.22 for platelets, these data suggested a pronounced selectivity for the phospholipase A2 and/or acetyltransferase in the process of PAF production. When the experiments were repeated with cells that had been pretreated with phenylmethanesulfonylfluoride (PMSF) to block the acetylhydrolase, the most dramatic effects were observed on acetate incorporation into 1-acyl-2-acetyl-glycero-3-phosphocholine, which increased much more than that into 1-alk(en)yl-2-acetyl-glycero-3-phosphocholine. Under these conditions, the ratio of acetate incorporation into 1-ether linked vs 1-ester linked PAF analogs became 1.4±0.2 and 0.17±0.02 for PMN and platelets, respectively. These values are very close to the 1-ether linked vs 1-ester linked species in the diradylglycerophosphocholine precursors for PAF in the respective cell type. These data suggested that the selectivities of phospholipase A2 and/or acetyl transferase for etherlinked species, as observed in non-PMSF treated cells, are only apparent and caused by rapid degradation of the 1-acyl analog either before or after acetylation. In line with this interpretation, we demonstrated that 1-acyl-2-acetyl-GPC can be deacylated to water-soluble acetyl-GPC and GPC by sonicated PMN and platelets and that this deacylation is completely blocked in sonicates from PMSF-pretreated cells. In addition, evidence is presented which indicates that the enzyme responsible for deacylation may be a lysophospholipase.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

Abbreviations

PMN:

polymorphonuclear leukocytes

PAF:

platelet-activating factor

1-alk(en)yl-2-acetyl-GPC:

total 1-ether linked 2-acetyl-GPC, i.e., sum of 1-alkyl- and 1-alkenyl- species

PMSF:

phenylmethanesulfonylfluoride

acetyltransferase:

acetyl-CoA:lysoPAF acetyltransferase (EC 2.3.1.67)

acetylhydrolase:

PAF-acetylhydrolase (EC 3.1.1.47)

GP[14C]C:

glycero-3-phospho[14C]choline

HPLC:

high performance liquid chromatography

References

  1. Snyder, F. (1985)Med. Res. Rev. 5, 107–140.

    Article  PubMed  CAS  Google Scholar 

  2. Alonso, F., Henson, P.M., and Leslie, C.C. (1986)Biochim. Biophys. Acta 878, 273–280.

    PubMed  CAS  Google Scholar 

  3. Kramer, R.M., Jakubowski, J.A., and Deykin, D. (1988)Biochim. Biophys. Acta 959, 269–279.

    PubMed  CAS  Google Scholar 

  4. Lee, T.-C., Malone, B., Wasserman, S.I., Fitzgerald, V., and Snyder, F. (1982)Biochem. Biophys. Res. Commun. 105, 1303–1308.

    Article  PubMed  CAS  Google Scholar 

  5. Albert, D.H., and Snyder, F. (1983)J. Biol. Chem. 258, 97–102.

    PubMed  CAS  Google Scholar 

  6. Coeffier, E., Ninio, E., Le Couedic, J.P., and Chignard, M. (1986)Br. J. Haem. 62, 641–651.

    CAS  Google Scholar 

  7. Alam, I., and Silver, M.J. (1986)Biochim. Biophys. Acta 884, 67–72.

    PubMed  CAS  Google Scholar 

  8. Wykle, R.L., Malone, B., and Snyder, F. (1980)J. Biol. Chem. 255, 10256–10260.

    PubMed  CAS  Google Scholar 

  9. Lee, T.-C. (1985)J. Biol. Chem. 260, 10952–10955.

    PubMed  CAS  Google Scholar 

  10. Chap, H., Mauco, G., Simon, M.F., Benveniste, J., and Douste-Blazy, L. (1981)Nature 289, 312–314.

    Article  PubMed  CAS  Google Scholar 

  11. Mueller, H.W., O'Flaherty, J.T., and Wykle, R.L. (1984)J. Biol. Chem. 259, 14554–14559.

    PubMed  CAS  Google Scholar 

  12. Satouchi, K., Oda, M., Yasunaga, K., and Saito, K. (1985)Biochem. Biophys. Res. Commun. 128, 1409–1417.

    PubMed  CAS  Google Scholar 

  13. Blank, M.L., Lee, T.-C., Fitzgerald, V., and Snyder, F. (1981)J. Biol. Chem. 256, 175–178.

    PubMed  CAS  Google Scholar 

  14. Touqui, L., Jacquemin, C., Dumarey, C., and Vargaftig, B.B. (1985)Biochim. Biophys. Acta 833, 111–118.

    PubMed  CAS  Google Scholar 

  15. Touqui, L., Hatmi, M., and Vargaftig, B.B., (1985)Biochem. J. 229, 811–816.

    PubMed  CAS  Google Scholar 

  16. Sturk, A., Schaap, M.C.L., Prins, A., ten Cate, J.W., and van den Bosch, H. (1989)Biochim. Biophys. Acta 993, 148–156.

    PubMed  CAS  Google Scholar 

  17. Sturk, A., Schaap, M.C.L., ten Cate, J.W., Heymans, H.S.A., Schutgens, R.B.H., Przyrembel, H., and Borst, P. (1987)J. Clin. Invest. 79, 344–350.

    PubMed  CAS  Google Scholar 

  18. Bligh, E.G., and Dyer, W.J. (1959)Can. J. Biochem. Physiol. 37, 911–917.

    PubMed  CAS  Google Scholar 

  19. Blank, M.L., and Snyder, F. (1983)J. Chromat. 273, 415–420.

    CAS  Google Scholar 

  20. van den Bosch, H., Slotboom, A.J., and van Deenen, L.L.M. (1969)Biochim. Biophys. Acta 176, 632–634.

    PubMed  Google Scholar 

  21. Kumar, R., Weintraub, S.T., McManus, L.M., Pinckard, R.N., and Hanahan, D.J. (1984)J. Lipid Res. 25, 198–208.

    PubMed  CAS  Google Scholar 

  22. Mueller, H.W., O'Flaherty, J.T., Greene, D.G., Samuel, M.P., and Wykle, R.L. (1983)J. Lipid Res. 25, 383–388.

    Google Scholar 

  23. Mueller, H.W., Purdon, A.D., Smith, J.B., and Wykle, R.L. (1983)Lipids 18, 814–819.

    Article  PubMed  CAS  Google Scholar 

  24. Waku, K., and Lands, W.E.M. (1968)J. Biol. Chem. 243, 2654–2659.

    PubMed  CAS  Google Scholar 

  25. Nakagawa, Y., Kurihara, K., Sugiura, T., and Waku, K. (1985)Eur. J. Biochem. 153, 263–268.

    Article  PubMed  CAS  Google Scholar 

  26. McKean, M.L., and Silver, M.J. (1985)Biochem. J. 225, 723–729.

    PubMed  CAS  Google Scholar 

  27. Lands, W.E.M., and Hart, P. (1985)J. Biol. Chem. 240, 1905–1911.

    Google Scholar 

  28. van den Bosch, H. (1982) inNew Comprehensive Biochemistry (Neuberger, A., and van Deenen, L.L.M., eds.) Vol. 4, pp. 313–357, Elsevier, Amsterdam.

    Google Scholar 

  29. van den Bosch, H., Aarsman, A.J., Slotboom, A.J., and van Deenen, L.L.M. (1968)Biochim. Biophys. Acta 164, 215–225.

    PubMed  Google Scholar 

  30. van den Bosch, H., Aarsman, A.J., de Jong, J.G.N., and van Deenen, L.L.M. (1973)Biochim. Biophys. Acta 296, 94–104.

    PubMed  Google Scholar 

  31. Aarsman, A.J., and van den Bosch, H. (1979)Biochim. Biophys. Acta 572, 519–530.

    PubMed  CAS  Google Scholar 

  32. De Jong, J.G.N., van den Bosch, H., Rijken, D., and van Deenen, L.L.M. (1973)Biochim. Biophys. Acta 369, 50–63.

    Google Scholar 

  33. Sugiura, T., Soga, N., Nitta, H., and Waku, K. (1983)J. Biochem. 94, 1719–1722.

    PubMed  CAS  Google Scholar 

  34. Smith, J.B., Dangelmaier, C., and Mauco, G. (1985)Biochim. Biophys. Acta 835, 344–351.

    PubMed  CAS  Google Scholar 

  35. McKean, M.L., Smith, J.B., and Silver, M.J. (1981)J. Biol. Chem. 256, 1522–1524.

    PubMed  CAS  Google Scholar 

  36. Walsh, C.E., Waite, B.M., Thomas, M.J., and De Chatelet, L.R. (1981)J. Biol. Chem. 256, 7228–7234.

    PubMed  CAS  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

About this article

Cite this article

van den Bosch, H., Sturk, A., ten Cate, J.W. et al. Studies on the selectivity of enzymes involved in platelet-activating factor formation in stimulated cells. Lipids 26, 967–973 (1991). https://doi.org/10.1007/BF02536486

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF02536486

Keywords

Navigation