Hepatic heme synthesis in a new model of experimental hemochromatosis: Studies in rats fed finely divided elemental iron
Corresponding Author
Herbert L. Bonkovsky M.D.
Department of Medicine and Biochemistry and the Clinical Research Center, Emory University School of Medicine, Atlanta, Georgia, 30322
Department of Medicine, Case Western Reserve University School of Medicine at Cleveland Metropolitan General Hospital, Cleveland, Ohio, 44109
Division of Medical Genetics, Mount Sinai Medical Center, New York, New York, 10029
Department of Medical Biochemistry, University of Wales College of Medicine, Cardiff, Wales CF4–4XN
Emory University, Clinical Research Center, 1364 Clifton Road, N.E., Atlanta, Georgia 30322===Search for more papers by this authorJohn F. Healey
Department of Medicine and Biochemistry and the Clinical Research Center, Emory University School of Medicine, Atlanta, Georgia, 30322
Department of Medicine, Case Western Reserve University School of Medicine at Cleveland Metropolitan General Hospital, Cleveland, Ohio, 44109
Division of Medical Genetics, Mount Sinai Medical Center, New York, New York, 10029
Department of Medical Biochemistry, University of Wales College of Medicine, Cardiff, Wales CF4–4XN
Search for more papers by this authorBeth Lincoln
Department of Medicine and Biochemistry and the Clinical Research Center, Emory University School of Medicine, Atlanta, Georgia, 30322
Department of Medicine, Case Western Reserve University School of Medicine at Cleveland Metropolitan General Hospital, Cleveland, Ohio, 44109
Division of Medical Genetics, Mount Sinai Medical Center, New York, New York, 10029
Department of Medical Biochemistry, University of Wales College of Medicine, Cardiff, Wales CF4–4XN
Search for more papers by this authorBruce R. Bacon
Department of Medicine and Biochemistry and the Clinical Research Center, Emory University School of Medicine, Atlanta, Georgia, 30322
Department of Medicine, Case Western Reserve University School of Medicine at Cleveland Metropolitan General Hospital, Cleveland, Ohio, 44109
Division of Medical Genetics, Mount Sinai Medical Center, New York, New York, 10029
Department of Medical Biochemistry, University of Wales College of Medicine, Cardiff, Wales CF4–4XN
Search for more papers by this authorDavid F. Bishop
Department of Medicine and Biochemistry and the Clinical Research Center, Emory University School of Medicine, Atlanta, Georgia, 30322
Department of Medicine, Case Western Reserve University School of Medicine at Cleveland Metropolitan General Hospital, Cleveland, Ohio, 44109
Division of Medical Genetics, Mount Sinai Medical Center, New York, New York, 10029
Department of Medical Biochemistry, University of Wales College of Medicine, Cardiff, Wales CF4–4XN
Search for more papers by this authorGeorge H. Elder
Department of Medicine and Biochemistry and the Clinical Research Center, Emory University School of Medicine, Atlanta, Georgia, 30322
Department of Medicine, Case Western Reserve University School of Medicine at Cleveland Metropolitan General Hospital, Cleveland, Ohio, 44109
Division of Medical Genetics, Mount Sinai Medical Center, New York, New York, 10029
Department of Medical Biochemistry, University of Wales College of Medicine, Cardiff, Wales CF4–4XN
Search for more papers by this authorCorresponding Author
Herbert L. Bonkovsky M.D.
Department of Medicine and Biochemistry and the Clinical Research Center, Emory University School of Medicine, Atlanta, Georgia, 30322
Department of Medicine, Case Western Reserve University School of Medicine at Cleveland Metropolitan General Hospital, Cleveland, Ohio, 44109
Division of Medical Genetics, Mount Sinai Medical Center, New York, New York, 10029
Department of Medical Biochemistry, University of Wales College of Medicine, Cardiff, Wales CF4–4XN
Emory University, Clinical Research Center, 1364 Clifton Road, N.E., Atlanta, Georgia 30322===Search for more papers by this authorJohn F. Healey
Department of Medicine and Biochemistry and the Clinical Research Center, Emory University School of Medicine, Atlanta, Georgia, 30322
Department of Medicine, Case Western Reserve University School of Medicine at Cleveland Metropolitan General Hospital, Cleveland, Ohio, 44109
Division of Medical Genetics, Mount Sinai Medical Center, New York, New York, 10029
Department of Medical Biochemistry, University of Wales College of Medicine, Cardiff, Wales CF4–4XN
Search for more papers by this authorBeth Lincoln
Department of Medicine and Biochemistry and the Clinical Research Center, Emory University School of Medicine, Atlanta, Georgia, 30322
Department of Medicine, Case Western Reserve University School of Medicine at Cleveland Metropolitan General Hospital, Cleveland, Ohio, 44109
Division of Medical Genetics, Mount Sinai Medical Center, New York, New York, 10029
Department of Medical Biochemistry, University of Wales College of Medicine, Cardiff, Wales CF4–4XN
Search for more papers by this authorBruce R. Bacon
Department of Medicine and Biochemistry and the Clinical Research Center, Emory University School of Medicine, Atlanta, Georgia, 30322
Department of Medicine, Case Western Reserve University School of Medicine at Cleveland Metropolitan General Hospital, Cleveland, Ohio, 44109
Division of Medical Genetics, Mount Sinai Medical Center, New York, New York, 10029
Department of Medical Biochemistry, University of Wales College of Medicine, Cardiff, Wales CF4–4XN
Search for more papers by this authorDavid F. Bishop
Department of Medicine and Biochemistry and the Clinical Research Center, Emory University School of Medicine, Atlanta, Georgia, 30322
Department of Medicine, Case Western Reserve University School of Medicine at Cleveland Metropolitan General Hospital, Cleveland, Ohio, 44109
Division of Medical Genetics, Mount Sinai Medical Center, New York, New York, 10029
Department of Medical Biochemistry, University of Wales College of Medicine, Cardiff, Wales CF4–4XN
Search for more papers by this authorGeorge H. Elder
Department of Medicine and Biochemistry and the Clinical Research Center, Emory University School of Medicine, Atlanta, Georgia, 30322
Department of Medicine, Case Western Reserve University School of Medicine at Cleveland Metropolitan General Hospital, Cleveland, Ohio, 44109
Division of Medical Genetics, Mount Sinai Medical Center, New York, New York, 10029
Department of Medical Biochemistry, University of Wales College of Medicine, Cardiff, Wales CF4–4XN
Search for more papers by this authorAbstract
Rats fed chow containing finely divided elemental iron (from carbonyl-iron) develop hepatic iron overload resembling human hereditary hemochromatosis in that deposition of iron is primarily in periportal hepatocytes and with hepatic iron concentrations sufficiently high to be associated in the human disease with hepatic fibrosis or cirrhosis. In recent studies using this model, we reported changes in hepatic hemoproteins and heme oxygenase, the rate-controlling enzyme of heme breakdown. We now report effects of iron-loading on three enzymes of heme synthesis: 5-aminolevulinate synthase; the first and rate-controlling enzyme of the pathway, 5-aminolevulinate dehydrase (or porphobilinogen synthase), and uroporphyrinogen decarboxylase, the activity of which is decreased in porphyria cutanea tarda, a liver disease in which iron is known to play an important but still poorly understood role. Of the three enzymes, only activity of the dehydrase was altered by iron-loading: it was decreased significantly as early as 1 week after starting iron feeding, and with marked iron overload was 30 to 32% of control values. The degree of decrease was inversely related (r = −0.77 to −0.88) to the degree of iron overload and was partially reversed within 1 to 3 days when feeding of the iron-supplemented diet was stopped. The decrease in dehydrase activity was not attributable to lack of reduced glutathione or other disulfide-reducing agents or to zinc deficiency; nor was evidence found for inhibition by iron compounds or other possible inhibitors present in iron-loaded livers. Immunochemical studies showed that the amount of 5-aminolevulinate dehydrase protein decreased in parallel to its decrease in activity, suggesting that iron-loading produced a reversible imbalance between the rate of synthesis and breakdown of the enzyme.
References
- 1 Bonkovsky HL, Carpenter SJ, Healey JF. Iron and the liver: subcellular distribution of iron and decreased microsomal cytochrome P-450 in livers of iron-loaded rats. Arch Pathol Lab Med 1979; 103: 21–29.
- 2 Bonkovsky HL, Sinclair P, Sinclair JF. Hepatic heme metabolism and its control. Yale J Biol Med 1979; 52: 13–37.
- 3 Bonkovsky HL, Healey JF, Sinclair PR, et al. Iron and the liver. Acute and long-term effects of iron-loading on hepatic haem metabolism. Biochem J 1981; 196: 57–64.
- 4 Bonkovsky HL, Healey JF, Sinclair PR, et al. Iron and the liver: acute effects of iron-loading on hepatic heme synthesis of rats. J Clin Invest 1983; 71: 1175–1182.
- 5 DeMatteis F, Sparks RG. Iron-dependent loss of liver cytochrome P-450 haem in vivo and in vitro. FEBS Lett 1973; 29: 141–144.
- 6 Ibrahim NG, Hoffstein ST, Freedman JL. Induction of liver cell heme oxygenase in iron overloaded rats. Biochem J 1979: 180: 257–263.
- 7 Ibrahim NG, Nelson JC, Levere RD. Control of δ-aminolevulinate synthase and heme oxygenase in chronic iron-overloaded rats. Biochem J 1981; 200: 35–42.
- 8 Bonkovsky HL. Porphyrin and heme metabolism and the porphyrias. In: D Zakim, TD Boyer, eds. Hepatology: a textbook of liver disease. Philadelphia, Pennsylvania: W. B. Saunders, 1982: 351–393.
- 9 Pimstone NR. Porphyria cutanea tarda. Semin Liver Dis 1982; 2: 132–142.
- 10 Bacon BR, Tavill AS, Brittenham GM, et al. Hepatic lipid peroxidation in vivo in rats with chronic iron overload. J Clin Invest 1983; 71: 429–439.
- 11 Bacon BR, Healey JF, Brittenham GM, et al. Hepatic microsomal function in rats with chronic dietary iron overload. Gastroenterology 1986; 90: 1844–1853.
- 12 Blankaert N, Schmid R. Physiology and pathophysiology of bilirubin metabolism. In: D Zakim, TD Boyer, eds. Hepatology: a textbook of liver disease. Philadelphia, Pennsylvania: W. B. Saunders, 1982: 246–296.
- 13 Hershey CO, Hershey LA, Wongmongkolrit T, et al. Trace element content of brain in Alzheimer disease and aging. Trace Elements in Med 1985; 2: 40–43.
- 14 Mostow MD, O'Neill R, Noon DL, et al. Bacon BR. Determination of α-tocopherol in rat liver by high performance liquid chromatography utilizing ultraviolet detection. J Chromatog Biomed Appl 1985; 344: 137–143.
- 15 Grandchamp B, Deybach JC, Grelier M, et al. Studies of porphyrin synthesis in fibroblasts of patients with congenital erythropoietic porphyria and one patient with homozygous coproporphyria. Biochim Biophys Acta 1980; 629: 577–586.
- 16 Bonkovsky HL, Wood SG, Howell SK, et al. HPLC separation and quantification of tetrapyrroles from biological materials. Anal Biochem 1986; 155: 56–64.
- 17 Elder GH, Wyvill PC, Assay of uroporphyrinogen decarboxylase. Enzyme 1982; 28: 186–193.
- 18 Anderson PM, Desnick RJ. Purification and properties of δ-aminolevulinate dehydratase from human erythrocytes. J Biol Chem 1979; 254: 6924–6930.
- 19 Anderson PM, Reddy RM, Anderson KE, et al. Characterization of the porphobilinogen deaminase deficiency in acute intermittent porphyria. J Clin Invest 1981; 68: 1–12.
- 20 Harboe N, Ingeld A. Immunization, isolation of immunoglobulins, estimation of antibody titre. Scand J Immunol 1973; 2 (Suppl 1): 161–162.
- 21 Dixon WJ, Massey FJ Jr. Introduction to statistical analysis, 3rd ed. New York: McGraw-Hill, 1969: 109–126. 150–192.
- 22 Shemin D. δ-Aminolevulinic acid dehydratase. In: P Boyer, ed. The enzymes, 3rd ed. New York: Academic Press, 1972: 323–337.
- 23 Jaffe EK, Saalowe SP, Chen NT, et al. Porphobilinogen synthase. Modification with methylmethanethiosulfonate. J Biol Chem 1984; 259: 5032–5036.
- 24 Keberle H. The biochemistry of desferrioxamine and its relation to iron metabolism. Ann NY Acad Sci 1964; 119: 758–768.
- 25 Dailey HA Jr, Lascelles J. Reduction of iron and synthesis of protoheme by Spirillum iterosnii and other organisms. J Bacteriol 1977; 129: 815–820.
- 26 Fujita H, Orii Y, Sano S. Evidence of increased synthesis of δ-aminolevulinic acid dehydratase in experimental lead-poisoned rats. Biochim Biophys Acta 1981; 678: 39–50.
- 27 Stein JA, Tschudy DP, Corcoran PL, et al. δ-Aminolevulinic acid synthetase. III. Synergistic effect of chelated iron on induction. J Biol Chem 1970; 245: 2213–2218.
- 28 Kushner JP, Lee GR, Nacht S. The role of iron in the pathogenesis of porphyria cutanea tarda. An in vitro model. J Clin Invest 1972; 51: 3044–3051.
- 29 Kushner JP, Steinmuller DP, Lee GR. The role of iron in the pathogenesis of porphyria cutanea tarda. II. Inhibition of uroporphyrinogen decarboxylase. J Clin Invest 1975; 66: 661–667.
- 30 Blekkenhorst GH, Eales L, Pimstone NR. Activation of uroporphyrinogen decarboxylase by ferrous iron in porphyria cutanea tarda. S Afr Med J 1979; 56: 918–920.
- 31 DeVerneuil H, Sassa S, Kappas A. Purification and properties of uroporphyrinogen decarboxylase from human erythrocytes: a single enzyme catalyzing the four sequential decarboxylations of uroporphyrinogens I and III. J Biol Chem 1982; 258: 2454–2460.
- 32 Mukerji SK, Pimstone NR, Burns M. Dual mechanism of inhibition of rat liver uroporphyrinogen decarboxylase activity by ferrous iron: its potential role in the genesis of porphyria cutanea tarda. Gastroenterology 1984; 87: 1248–1254.
- 33 Fairbanks VF, Fahey JL, Beutler E. Clinical disorders of iron metabolism, 2nd ed. New York: Grune and Stratton, 1971: 47–54.
- 34 Koizumi A, Firjita H, Sadamoto T, et al. Inhibition of δ-aminolevulinic acid dehydratase by trichlorethylene. Toxicology 1984; 30: 93–102.
- 35 Koizumi A, Firjita H, Sadamoto T, et al. Cytochrome P-450 system dependent depression of δ-aminolevulinic acid dehydratase activity by bromobenzene in rats. Toxicology 1984; 32: 1–10.
- 36 Kodama T, Kondo M, Urata G, et al. Changes in aminolevulinate synthase and aminolevulinate dehydratase activity in cirrhotic liver. Gastroenterology 1983; 84: 236–241.
- 37 Kondo M, Urata G, Shimizu Y. Decreased liver δ-aminolevulinate dehydratase activity in porphyria cutanea tarda and in alcoholism. Clin Sci 1983; 65: 423–428.
- 38 Kennedy SW, Wigfield DC, Fox GA. The delay in polyhalogenated aromatic hydrocarbon-induced porphyria: mechanistic reality or methodological artefact? Toxicol Lett 1986; 31: 235–241.
