The relationship between heme synthesis and iron uptake in erythroid cells.
Hemin inhibited 59Fe uptake from transferrin (Tf) by mouse erythro-leukemia cells (MELC) induced for differentiation by hexamethylene bisacetamide (HMBA), but the rate and the extent of 125I-Tf endocytosis was unaffected. Hemin inhibited 59Fe incorporation into heme by a greater proportion than the overall uptake of 59Fe from Tf. Desferrioxamine (DFO) reverted the inhibition of 59Fe transport into MELC caused by hemin. Exogenous 5-aminolevulinic acid (ALA) stimulated 59Fe utilization for heme synthesis in MELC but did not revert inhibition induced by hemin. No evidence for a direct effect of heme on the Tf cycle or iron release was found.
Hradilek
A
A
Institute of Hematology and Blood Transfusion, Prague, Czechoslovakia.
Neuwirt
J
J
D000818:Animals; D005622:Friend murine leukemia virus; D006418:Heme / Q000096:biosynthesis*; D006427:Hemin / Q000494:pharmacology; D007501:Iron / Q000378:metabolism*; D004915:Leukemia, Erythroblastic, Acute / Q000378:metabolism*; D051379:Mice; D014168:Transferrin / Q000378:metabolism; D014407:Tumor Cells, Cultured
D014168:Transferrin; D006418:Heme; D006427:Hemin; D007501:Iron