Skip to main content
The Journal of Clinical Investigation logoLink to The Journal of Clinical Investigation
. 1986 Mar;77(3):934–939. doi: 10.1172/JCI112392

Irreversible binding of zomepirac to plasma protein in vitro and in vivo.

P C Smith, A F McDonagh, L Z Benet
PMCID: PMC423485  PMID: 3949982

Abstract

Zomepirac is a nonsteroidal anti-inflammatory drug recently withdrawn from use because of an unexplained high incidence of immunological reactions. It is metabolized in humans to a reactive, unstable acyl glucuronide which accumulates in plasma. Because of the similarity of zomepirac glucuronide to bilirubin glucuronide in structure and stability and the documented irreversible binding of bilirubin to albumin through its acyl glucuronide, we studied the reaction of zomepirac acyl glucuronide with albumin in vitro from pH 5 to 9 and in vivo in six healthy human volunteers who had received a single 100-mg oral dose of zomepirac. Irreversible binding of zomepirac to protein was determined by exhaustive washing of protein, followed by hydrolysis of bound zomepirac-protein adduct with base, extraction of the liberated drug, and chromatographic measurement. Irreversible binding was observed both in vitro and in vivo. The extent of binding in vitro was time- and pH-dependent. In vitro drug binding was also observed for the isomers of zomepirac glucuronide which were formed by intramolecular acyl migration. Irreversible binding in vivo correlated with overall exposure to zomepirac glucuronide when exposure was expressed as the area under the plasma concentration vs. time curve. When probenecid (500 mg, twice daily), which decreases the plasma clearance of zomepirac glucuronide, was administered concurrently with zomepirac, irreversible binding of zomepirac was increased. The nature of the zomepirac protein binding is probably covalent. Formation of irreversibly protein-bound zomepirac occurs via the acyl glucuronide as previously shown for bilirubin glucuronide, and the reaction may be general for other drugs that are metabolized to acyl glucuronides.

Full text

PDF
934

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Bakke O. M., Wardell W. M., Lasagna L. Drug discontinuations in the United Kingdom and the United States, 1964 to 1983: issues of safety. Clin Pharmacol Ther. 1984 May;35(5):559–567. doi: 10.1038/clpt.1984.78. [DOI] [PubMed] [Google Scholar]
  2. Bunn H. F., Gabbay K. H., Gallop P. M. The glycosylation of hemoglobin: relevance to diabetes mellitus. Science. 1978 Apr 7;200(4337):21–27. doi: 10.1126/science.635569. [DOI] [PubMed] [Google Scholar]
  3. Clive D. M., Stoff J. S. Renal syndromes associated with nonsteroidal antiinflammatory drugs. N Engl J Med. 1984 Mar 1;310(9):563–572. doi: 10.1056/NEJM198403013100905. [DOI] [PubMed] [Google Scholar]
  4. Faed E. M. Properties of acyl glucuronides: implications for studies of the pharmacokinetics and metabolism of acidic drugs. Drug Metab Rev. 1984;15(5-6):1213–1249. doi: 10.3109/03602538409033562. [DOI] [PubMed] [Google Scholar]
  5. Garlick R. L., Mazer J. S. The principal site of nonenzymatic glycosylation of human serum albumin in vivo. J Biol Chem. 1983 May 25;258(10):6142–6146. [PubMed] [Google Scholar]
  6. Gautam A., Seligson H., Gordon E. R., Seligson D., Boyer J. L. Irreversible binding of conjugated bilirubin to albumin in cholestatic rats. J Clin Invest. 1984 Mar;73(3):873–877. doi: 10.1172/JCI111283. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Hasegawa J., Smith P. C., Benet L. Z. Apparent intramolecular acyl migration of zomepirac glucuronide. Drug Metab Dispos. 1982 Sep-Oct;10(5):469–473. [PubMed] [Google Scholar]
  8. Higgins P. J., Bunn H. F. Kinetic analysis of the nonenzymatic glycosylation of hemoglobin. J Biol Chem. 1981 May 25;256(10):5204–5208. [PubMed] [Google Scholar]
  9. Koenig R. J., Blobstein S. H., Cerami A. Structure of carbohydrate of hemoglobin AIc. J Biol Chem. 1977 May 10;252(9):2992–2997. [PubMed] [Google Scholar]
  10. Kuenzle C. C., Maier C., Rüttner J. R. The nature of four bilirubin fractions from serum and of three bilirubin fractions from bile. J Lab Clin Med. 1966 Feb;67(2):294–306. [PubMed] [Google Scholar]
  11. Langendijk P. N., Smith P. C., Hasegawa J., Benet L. Z. Simultaneous determination of zomepirac and its major metabolite zomepirac glucuronide in human plasma and urine. J Chromatogr. 1984 May 11;307(2):371–379. doi: 10.1016/s0378-4347(00)84108-0. [DOI] [PubMed] [Google Scholar]
  12. Lauff J. J., Kasper M. E., Ambrose R. T. Quantitative liquid-chromatographic estimation of bilirubin species in pathological serum. Clin Chem. 1983 May;29(5):800–805. [PubMed] [Google Scholar]
  13. Lauff J. J., Kasper M. E., Ambrose R. T. Separation of bilirubin species in serum and bile by high-performance reversed-phase liquid chromatography. J Chromatogr. 1981 Dec 11;226(2):391–402. doi: 10.1016/s0378-4347(00)86073-9. [DOI] [PubMed] [Google Scholar]
  14. Lauff J. J., Kasper M. E., Wu T. W., Ambrose R. T. Isolation and preliminary characterization of a fraction of bilirubin in serum that is firmly bound to protein. Clin Chem. 1982 Apr;28(4 Pt 1):629–637. [PubMed] [Google Scholar]
  15. McDonagh A. F., Palma L. A., Lauff J. J., Wu T. W. Origin of mammalian biliprotein and rearrangement of bilirubin glucuronides in vivo in the rat. J Clin Invest. 1984 Sep;74(3):763–770. doi: 10.1172/JCI111492. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. O'Neill P. J., Yorgey K. A., Renzi N. L., Jr, Williams R. L., Benet L. Z. Disposition of zomepirac sodium in man. J Clin Pharmacol. 1982 Oct;22(10):470–476. doi: 10.1002/j.1552-4604.1982.tb02637.x. [DOI] [PubMed] [Google Scholar]
  17. Pohl L. R., Branchflower R. V. Covalent binding of electrophilic metabolites to macromolecules. Methods Enzymol. 1981;77:43–50. doi: 10.1016/s0076-6879(81)77009-5. [DOI] [PubMed] [Google Scholar]
  18. Samuel S. A. Apparent anaphylactic reaction to zomepirac (Zomax) N Engl J Med. 1981 Apr 16;304(16):978–978. doi: 10.1056/NEJM198104163041619. [DOI] [PubMed] [Google Scholar]
  19. Shaklai N., Garlick R. L., Bunn H. F. Nonenzymatic glycosylation of human serum albumin alters its conformation and function. J Biol Chem. 1984 Mar 25;259(6):3812–3817. [PubMed] [Google Scholar]
  20. Smith P. C., Langendijk P. N., Bosso J. A., Benet L. Z. Effect of probenecid on the formation and elimination of acyl glucuronides: studies with zomepirac. Clin Pharmacol Ther. 1985 Aug;38(2):121–127. doi: 10.1038/clpt.1985.146. [DOI] [PubMed] [Google Scholar]
  21. Stogniew M., Fenselau C. Electrophilic reactions of acyl-linked glucuronides. Formation of clofibrate mercapturate in humans. Drug Metab Dispos. 1982 Nov-Dec;10(6):609–613. [PubMed] [Google Scholar]
  22. Weiss J. S., Gautam A., Lauff J. J., Sundberg M. W., Jatlow P., Boyer J. L., Seligson D. The clinical importance of a protein-bound fraction of serum bilirubin in patients with hyperbilirubinemia. N Engl J Med. 1983 Jul 21;309(3):147–150. doi: 10.1056/NEJM198307213090305. [DOI] [PubMed] [Google Scholar]
  23. van Breemen R. B., Fenselau C. Acylation of albumin by 1-O-acyl glucuronides. Drug Metab Dispos. 1985 May-Jun;13(3):318–320. [PubMed] [Google Scholar]

Articles from Journal of Clinical Investigation are provided here courtesy of American Society for Clinical Investigation

RESOURCES