The treatment of acute intermittent porphyria with laevulose.
1. The activities of the enzymes of haem biosynthesis were studied in 23 patients with acute intermittent porphyria. The mitochondrial enzymes delta-aminolaevulinate synthase, coproporphyrinogen oxidase and ferrochelatase were measured in leucocytes and the cytosolic enzymes delta-aminolaevulinate dehydratase, porphobilinogen deaminase and uroporphyrinogen decarboxylase in erythrocytes. 2. Leucocyte delta-aminolaevulinate synthase activity was elevated (P less than 0-001), with marked diminution of porphobilinogen deaminase activity (P less than 0-001) and reduction in the activities of delta-aminolaevulinate dehydratase (P less than 0-01) and uroporphyrinogen decarboxylase (P less than 0-005). 3. A therapeutic regimen based on intravenous laevulose infusion was studied. In four patients in acute attack and one in remission laevulose treatment was associated with a fall in delta-aminolaevulinate synthase activity, a rise in porphobilinogen deaminase and uroporphyrinogen decarboxylase activities, and a fall in urinary prophyrin precursor excretion (P less than 0-001). These studies provide a basis for the evaluation of the use of sugars in acute intermittent porphyria.
D000624:5-Aminolevulinate Synthetase / Q000378:metabolism; D003304:Coproporphyrinogen Oxidase / Q000378:metabolism; D004912:Erythrocytes / Q000201:enzymology; D005294:Ferrochelatase / Q000378:metabolism; D005632:Fructose / Q000627:therapeutic use*; D006418:Heme / Q000096:biosynthesis; D006801:Humans; D011163:Hydroxymethylbilane Synthase / Q000378:metabolism; D007962:Leukocytes / Q000201:enzymology; D000623:Porphobilinogen Synthase / Q000378:metabolism; D011164:Porphyrias / Q000188:drug therapy* / Q000201:enzymology; D014575:Uroporphyrinogen Decarboxylase / Q000378:metabolism
D005632:Fructose; D006418:Heme; D003304:Coproporphyrinogen Oxidase; D000624:5-Aminolevulinate Synthetase; D011163:Hydroxymethylbilane Synthase; D014575:Uroporphyrinogen Decarboxylase; D000623:Porphobilinogen Synthase; D005294:Ferrochelatase