Effect of glycine loading on Delta-Aminolevulinic acid (ALA) and porphobilinogen (PBG) excretion during starvation

The "glucose effect" in acute hepatic porphyrias and in experimental porphyria

The "glucose effect" was investigated in human acute hepatic porphyrias (acute intermittent porphyria, variegate porphyria, coproporphyria and porphobilinogen synthase defect porphyria) and in avian liver cells. 8 patients (7 women) with acute abdominal-neurological porphyria syndrome and 3 patients (2 women) in the remission phase were treated with high carbohydrate intake (approximately 500 g/24 h), mainly in form of intravenous glucose infusions. The biochemical response with a decrease of metabolites of porphyrin biosynthesis was highly significant, accompanied by clinical improvement in 10 courses of 9 patients. Two patients with delayed detection of the disease under the condition of Landry paralysis died after temporary clinical improvement due to ventricular arrythmias in one case and septicemia in the other. The importance of early diagnosis and therapy, and omission of drugs and alcohol cannot be overemphasized. Complementary studies show the "glucose effect" in drug -mediated induction of porphyrin synthesis in liver cells grown in culture: delta-Aminolevulinic acid synthase and protoporphyrin synthesis are repressed.