Skip to main content
Biochemical Journal logoLink to Biochemical Journal
. 1996 Nov 1;319(Pt 3):897–902. doi: 10.1042/bj3190897

Divergent effects of alpha 1-antitrypsin on the regulation of iron metabolism in human erythroleukaemic (K562) and myelomonocytic (THP-1) cells.

G Weiss 1, I Graziadel 1, M Urbanek 1, K Grünewald 1, W Vogel 1
PMCID: PMC1217872  PMID: 8920996

Abstract

The acute-phase protein alpha 1-antitrypsin (alpha 1-AT) has been shown to inhibit the binding of transferrin to its cell-surface receptor. Here we demonstrate that in human erythroleukaemic cells (K562) alpha 1-AT enhances the binding affinity of iron-regulatory protein (IRP), the central regulator of cellular iron metabolism, to iron-responsive elements. Activation of IRP by alpha 1-AT is associated with a marked increase in transferrin receptor (trf-rec) mRNA levels in K562 and enhanced cell-surface expression of transferrin-binding sites, whereas ferritin production is decreased, although ferritin mRNA levels remain unchanged. In agreement with the well-established mechanism of cellular iron regulation, alpha 1-AT seems to modulate trf-rec and ferritin expression primarily post-transcriptionally/translationally by influencing IRP activity. In contrast, alpha 1-AT produces only minor changes in IRP activity, and subsequently in trf-rec expression and ferritin synthesis in THP-1 cells. Moreover the effects of alpha 1-AT on iron homeostasis in K562 cannot be overcome by the addition of iron salts, whereas concomitant treatment of THP-1 with iron and alpha 1-AT results in the same metabolic changes as the addition of iron alone. Because alpha 1-AT blocks transferrin binding on K562 as well as on THP-1 cells, it is suggested, on the basis of the results presented here, (1) that erythroid and monocytic cells might differ in their dependence on transferrin-mediated iron supply and (2) that THP-1 might be able to acquire iron by a transferrin-independent iron uptake system. alpha 1-AT might therefore be involved in the diversion of iron traffic between various cellular compartments under inflammatory conditions.

Full Text

The Full Text of this article is available as a PDF (256.4 KB).

Selected References

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

  1. Aziz N., Munro H. N. Iron regulates ferritin mRNA translation through a segment of its 5' untranslated region. Proc Natl Acad Sci U S A. 1987 Dec;84(23):8478–8482. doi: 10.1073/pnas.84.23.8478. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Banda M. J., Rice A. G., Griffin G. L., Senior R. M. The inhibitory complex of human alpha 1-proteinase inhibitor and human leukocyte elastase is a neutrophil chemoattractant. J Exp Med. 1988 May 1;167(5):1608–1615. doi: 10.1084/jem.167.5.1608. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Bomford A., Isaac J., Roberts S., Edwards A., Young S., Williams R. The effect of desferrioxamine on transferrin receptors, the cell cycle and growth rates of human leukaemic cells. Biochem J. 1986 May 15;236(1):243–249. doi: 10.1042/bj2360243. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Bradford M. M. A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal Biochem. 1976 May 7;72:248–254. doi: 10.1006/abio.1976.9999. [DOI] [PubMed] [Google Scholar]
  5. Byrd T. F., Horwitz M. A. Lactoferrin inhibits or promotes Legionella pneumophila intracellular multiplication in nonactivated and interferon gamma-activated human monocytes depending upon its degree of iron saturation. Iron-lactoferrin and nonphysiologic iron chelates reverse monocyte activation against Legionella pneumophila. J Clin Invest. 1991 Oct;88(4):1103–1112. doi: 10.1172/JCI115409. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Casey J. L., Koeller D. M., Ramin V. C., Klausner R. D., Harford J. B. Iron regulation of transferrin receptor mRNA levels requires iron-responsive elements and a rapid turnover determinant in the 3' untranslated region of the mRNA. EMBO J. 1989 Dec 1;8(12):3693–3699. doi: 10.1002/j.1460-2075.1989.tb08544.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Caughman S. W., Hentze M. W., Rouault T. A., Harford J. B., Klausner R. D. The iron-responsive element is the single element responsible for iron-dependent translational regulation of ferritin biosynthesis. Evidence for function as the binding site for a translational repressor. J Biol Chem. 1988 Dec 15;263(35):19048–19052. [PubMed] [Google Scholar]
  8. Dautry-Varsat A., Ciechanover A., Lodish H. F. pH and the recycling of transferrin during receptor-mediated endocytosis. Proc Natl Acad Sci U S A. 1983 Apr;80(8):2258–2262. doi: 10.1073/pnas.80.8.2258. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Feinberg A. P., Vogelstein B. A technique for radiolabeling DNA restriction endonuclease fragments to high specific activity. Anal Biochem. 1983 Jul 1;132(1):6–13. doi: 10.1016/0003-2697(83)90418-9. [DOI] [PubMed] [Google Scholar]
  10. Gray N. K., Hentze M. W. Iron regulatory protein prevents binding of the 43S translation pre-initiation complex to ferritin and eALAS mRNAs. EMBO J. 1994 Aug 15;13(16):3882–3891. doi: 10.1002/j.1460-2075.1994.tb06699.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Graziadei I., Gaggl S., Kaserbacher R., Braunsteiner H., Vogel W. The acute-phase protein alpha 1-antitrypsin inhibits growth and proliferation of human early erythroid progenitor cells (burst-forming units-erythroid) and of human erythroleukemic cells (K562) in vitro by interfering with transferrin iron uptake. Blood. 1994 Jan 1;83(1):260–268. [PubMed] [Google Scholar]
  12. Graziadei I., Kaserbacher R., Braunsteiner H., Vogel W. The hepatic acute-phase proteins alpha 1-antitrypsin and alpha 2-macroglobulin inhibit binding of transferrin to its receptor. Biochem J. 1993 Feb 15;290(Pt 1):109–113. doi: 10.1042/bj2900109. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Halliwell B., Gutteridge J. M. Role of free radicals and catalytic metal ions in human disease: an overview. Methods Enzymol. 1990;186:1–85. doi: 10.1016/0076-6879(90)86093-b. [DOI] [PubMed] [Google Scholar]
  14. Hentze M. W., Rouault T. A., Caughman S. W., Dancis A., Harford J. B., Klausner R. D. A cis-acting element is necessary and sufficient for translational regulation of human ferritin expression in response to iron. Proc Natl Acad Sci U S A. 1987 Oct;84(19):6730–6734. doi: 10.1073/pnas.84.19.6730. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Hentze M. W., Rouault T. A., Harford J. B., Klausner R. D. Oxidation-reduction and the molecular mechanism of a regulatory RNA-protein interaction. Science. 1989 Apr 21;244(4902):357–359. doi: 10.1126/science.2711187. [DOI] [PubMed] [Google Scholar]
  16. Kaplan J., Jordan I., Sturrock A. Regulation of the transferrin-independent iron transport system in cultured cells. J Biol Chem. 1991 Feb 15;266(5):2997–3004. [PubMed] [Google Scholar]
  17. Klausner R. D., Ashwell G., van Renswoude J., Harford J. B., Bridges K. R. Binding of apotransferrin to K562 cells: explanation of the transferrin cycle. Proc Natl Acad Sci U S A. 1983 Apr;80(8):2263–2266. doi: 10.1073/pnas.80.8.2263. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Klausner R. D., Rouault T. A., Harford J. B. Regulating the fate of mRNA: the control of cellular iron metabolism. Cell. 1993 Jan 15;72(1):19–28. doi: 10.1016/0092-8674(93)90046-s. [DOI] [PubMed] [Google Scholar]
  19. Leibold E. A., Munro H. N. Cytoplasmic protein binds in vitro to a highly conserved sequence in the 5' untranslated region of ferritin heavy- and light-subunit mRNAs. Proc Natl Acad Sci U S A. 1988 Apr;85(7):2171–2175. doi: 10.1073/pnas.85.7.2171. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. Means R. T., Jr, Krantz S. B. Progress in understanding the pathogenesis of the anemia of chronic disease. Blood. 1992 Oct 1;80(7):1639–1647. [PubMed] [Google Scholar]
  21. Melefors O., Hentze M. W. Iron regulatory factor--the conductor of cellular iron regulation. Blood Rev. 1993 Dec;7(4):251–258. doi: 10.1016/0268-960x(93)90012-s. [DOI] [PubMed] [Google Scholar]
  22. Milligan J. F., Groebe D. R., Witherell G. W., Uhlenbeck O. C. Oligoribonucleotide synthesis using T7 RNA polymerase and synthetic DNA templates. Nucleic Acids Res. 1987 Nov 11;15(21):8783–8798. doi: 10.1093/nar/15.21.8783. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Morgan E. H., Appleton T. C. Autoradiographic localization of 125-I-labelled transferrin in rabbit reticulocytes. Nature. 1969 Sep 27;223(5213):1371–1372. doi: 10.1038/2231371a0. [DOI] [PubMed] [Google Scholar]
  24. Müllner E. W., Neupert B., Kühn L. C. A specific mRNA binding factor regulates the iron-dependent stability of cytoplasmic transferrin receptor mRNA. Cell. 1989 Jul 28;58(2):373–382. doi: 10.1016/0092-8674(89)90851-9. [DOI] [PubMed] [Google Scholar]
  25. Perlmutter D. H., Glover G. I., Rivetna M., Schasteen C. S., Fallon R. J. Identification of a serpin-enzyme complex receptor on human hepatoma cells and human monocytes. Proc Natl Acad Sci U S A. 1990 May;87(10):3753–3757. doi: 10.1073/pnas.87.10.3753. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Perlmutter D. H. Liver disease associated with alpha 1-antitrypsin deficiency. Prog Liver Dis. 1993;11:139–165. [PubMed] [Google Scholar]
  27. Perlmutter D. H., Punsal P. I. Distinct and additive effects of elastase and endotoxin on expression of alpha 1 proteinase inhibitor in mononuclear phagocytes. J Biol Chem. 1988 Nov 5;263(31):16499–16503. [PubMed] [Google Scholar]
  28. Rosen G. M., Pou S., Ramos C. L., Cohen M. S., Britigan B. E. Free radicals and phagocytic cells. FASEB J. 1995 Feb;9(2):200–209. doi: 10.1096/fasebj.9.2.7540156. [DOI] [PubMed] [Google Scholar]
  29. Rouault T. A., Hentze M. W., Caughman S. W., Harford J. B., Klausner R. D. Binding of a cytosolic protein to the iron-responsive element of human ferritin messenger RNA. Science. 1988 Sep 2;241(4870):1207–1210. doi: 10.1126/science.3413484. [DOI] [PubMed] [Google Scholar]
  30. Sturrock A., Alexander J., Lamb J., Craven C. M., Kaplan J. Characterization of a transferrin-independent uptake system for iron in HeLa cells. J Biol Chem. 1990 Feb 25;265(6):3139–3145. [PubMed] [Google Scholar]
  31. Testa U., Thomopoulos P., Vinci G., Titeux M., Bettaieb A., Vainchenker W., Rochant H. Transferrin binding to K562 cell line. Effect of heme and sodium butyrate induction. Exp Cell Res. 1982 Aug;140(2):251–260. doi: 10.1016/0014-4827(82)90112-4. [DOI] [PubMed] [Google Scholar]
  32. Theil E. C. Regulation of ferritin and transferrin receptor mRNAs. J Biol Chem. 1990 Mar 25;265(9):4771–4774. [PubMed] [Google Scholar]
  33. Thorstensen K., Romslo I. The role of transferrin in the mechanism of cellular iron uptake. Biochem J. 1990 Oct 1;271(1):1–9. doi: 10.1042/bj2710001. [DOI] [PMC free article] [PubMed] [Google Scholar]
  34. Travis J., Salvesen G. S. Human plasma proteinase inhibitors. Annu Rev Biochem. 1983;52:655–709. doi: 10.1146/annurev.bi.52.070183.003255. [DOI] [PubMed] [Google Scholar]
  35. Walden W. E., Patino M. M., Gaffield L. Purification of a specific repressor of ferritin mRNA translation from rabbit liver. J Biol Chem. 1989 Aug 15;264(23):13765–13769. [PubMed] [Google Scholar]
  36. Weiss G., Goossen B., Doppler W., Fuchs D., Pantopoulos K., Werner-Felmayer G., Wachter H., Hentze M. W. Translational regulation via iron-responsive elements by the nitric oxide/NO-synthase pathway. EMBO J. 1993 Sep;12(9):3651–3657. doi: 10.1002/j.1460-2075.1993.tb06039.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  37. Weiss G., Wachter H., Fuchs D. Linkage of cell-mediated immunity to iron metabolism. Immunol Today. 1995 Oct;16(10):495–500. doi: 10.1016/0167-5699(95)80034-4. [DOI] [PubMed] [Google Scholar]
  38. Weiss G., Werner-Felmayer G., Werner E. R., Grünewald K., Wachter H., Hentze M. W. Iron regulates nitric oxide synthase activity by controlling nuclear transcription. J Exp Med. 1994 Sep 1;180(3):969–976. doi: 10.1084/jem.180.3.969. [DOI] [PMC free article] [PubMed] [Google Scholar]
  39. van Renswoude J., Bridges K. R., Harford J. B., Klausner R. D. Receptor-mediated endocytosis of transferrin and the uptake of fe in K562 cells: identification of a nonlysosomal acidic compartment. Proc Natl Acad Sci U S A. 1982 Oct;79(20):6186–6190. doi: 10.1073/pnas.79.20.6186. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Biochemical Journal are provided here courtesy of The Biochemical Society

RESOURCES