Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.5.1.61 (porphobilinogen deaminase)
 637 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Acute intermittent porphyria has hitherto been recognised as an autosomal dominant inborn error of haem metabolism characterised by a depressed activity of the enzyme uroporphyrinogen I synthase (URO.S). A case of non-hereditary acute porphyria, similar to acute intermittent porphyria, following treatment of epilepsy with carbamazepine is reported. Subsequent measurements of erythrocyte URO.S activity in a group of epileptic patients treated with various combinations of anticonvulsant drugs suggest that carbamazepine exerts a direct suppressant effect on URO.S in addition to its indirect enzyme-inducing properties.
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PMID:Carbamazepine-induced non-hereditary acute porphyria. 613 32

In two male patients with acute hepatic porphyria and persisting paralysis which increased in intensity intermittently, the activity of porphobilinogen synthase (PBG-S; delta-aminolevulinic acid dehydr(at)ase) was diminished in peripheral erythrocytes and bone marrow cells below 3% of normal controls. In contrast, the activities of uroporphyrinogen synthase and decarboxylase were normal. Both patients have been excreting high quantities of delta-aminolevulinic acid and porphyrins in urine for years. Lead intoxication and tyrosinemia could definitely be excluded. There was no experimental evidence for the existence of an inhibitor to PBG-S in urine, serum and erythrocytes from these two patients. The PBG-S deficiency was confirmed after DEAE cellulose chromatography: the concordance of relative and specific activity before and after chromatography of PBG-S from patients and controls differs from the findings in lead poisoning. A mutation of PBG-S probably at the level of the structural gene is concluded as the molecular basis of the inherited PBG-S defect porphyria. Since the relatives also show lower activities of PBG-S (approximately 50% of controls), the disease of these two patients represents a new enzymatic type of inherited acute hepatic porphyria, the excretion profile of which is qualitatively completely different from those of the known acute porphyrias. The discovery of this porphyria confirms the theory of overlapping transition in the biochemical signs and clinical symptoms as well as analogies among the acute hepatic porphyrias and lead poisoning.
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PMID:New type of acute porphyria with porphobilinogen synthase (delta-aminolevulinic acid dehydratase) defect in the homozygous state. 706 77

Fifty-seven patients with variegate porphyria belonging to nine families are described. The prevalence of variegate porphyria in Finland is 1.3 per 100 000. Eighteen patients had had acute attacks. During on average 5.7 years' follow-up only two of 48 patients had symptoms, which were temporary and acute. The length of life of 13 genealogically traced gene carriers who lived mostly during the 19th century did not differ from that of the general population. Skin fragility occurred in 45 per cent of the patients and was usually mild. No patients were sensitive to sunlight but seven of 14 tested reacted abnormally to artificial light. The characteristic increase in the excretion of faecal proto- and coproporphyrin was usually apparent even in the latent stage of porphyria, but increased excretion of urinary porphyrin precursors occurred only during an acute attack. However, in seven of 48 patients studied during the latent stage, faecal prophyrins were only slightly elevated or even normal, causing problems in diagnosis. Determination of faecal X-porphyrin was of no help in diagnosis. Red cell free protoporphyrin was significantly higher and serum haemopexin lower than in controls. Red cell uroporphyrinogen I synthase activity was normal in 17 of 18 patients studied. We conclude that variegate porphyria may be commoner than hiherto suspected; only half the patients in temperaure and cold climates have skin symptoms, the risk of developing an acute attack is low, and some adult patients excrete normal or only slightly abnormal amounts of porphyrin.
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PMID:Variegate porphyria. Twelve years' experience in Finland. 743 35

In the last decades several authors have observed a frequent association between diabetes mellitus and porphyria, mainly porphyria cutanea tarda. In previous studies, it has been demonstrated that both d delta d-aminolevulic acid dehydratase (ALA-D) and porphobilinogen deaminase (PBG-D), enzymes of the heme pathway, are inhibited by high concentrations of glucose in vitro in crude preparations of erythrocytes. The activity of these same enzymes was diminished in different tissues obtained from streptozotocin induced diabetic mice. Therefore, we decided to investigate the incidence of heme metabolism alterations in diabetes mellitus in a population of 100 non selected adult patients. The activities of erythrocytic ALA-D and PBG-D were measured. Rhodanese, an enzyme of the sulfocompounds pathway closely related to the regulation of heme biosynthesis, was also studied. Urine porphyrin content as well as the chromatographic pattern of esterified porphyrins were determined. ALA-D and PBG-D activities were diminished in diabetic patients (40% and 20% respectively), while rhodanese was only slightly increased (Fig. 1). ALA-D activity was subnormal in a 92% of the complete diabetic population, while PBG-D activity was less than normal in a 79% of the same population. No significative differences between enzymic activities were observed in the groups insulin and non-insulin dependent (Fig. 3). Urine porphyrin content was increased in 5% of the diabetic population. Chromatographic pattern of urinary porphyrins was notably altered in diabetic patients irrespectively of their porphyrin content (Fig. 4), suggesting an alteration in the enzyme uroporphyrinogen decarboxylase resembling the primary enzymic defect observed in porphyria cutanea tarda.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Changes in the heme metabolic pathway in diabetic patients]. 756 48

There are 4 different porphyrin-synthesizing enzymes, i.e. delta-aminolevulinic acid dehydratase, porphobilinogen deaminase, uroporphyrinogen III synthase and uroporphyrinogen decarboxylase, in red blood cells. Determination of activities of these enzymes is of great help in clarifying the hemopoietic mechanism operating in bone marrow erythroblasts, as well as, in establishing the diagnosis of or early detection of acute intermittent porphyria, congenital erythropoietic porphyria, delta-aminolevulinic acid dehydratase deficiency porphyria, porphyria cutanea tarda and lead poisoning. This paper presents a summary of the techniques for the measuring, diagnostic criteria for and clinical implications of activities of these 4 enzymes in red blood cells.
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PMID:[Porphyrin-synthesizing enzymes in erythrocyte]. 761 49

The porphyrias are a group of metabolic disorders of heme biosynthesis genetically determined defects. Acute intermittent porphyria is the most common form of porphyria found in the United States. It is caused by a genetic defect in chromosome 11, where one of two genes for porphobilinogen deaminase is defective. Acute intermittent porphyria is characterized by intermittent, acute, occasionally fatal attacks of abdominal, neurologic, psychiatric, and renal symptoms. Attacks are often confused with acute abdomen or bowel obstruction. A variety of drug, hormonal, nutritional, and infectious factors can precipitate clinical symptoms. Managing patients with acute intermittent porphyria involves removing the precipitating factors, increasing carbohydrate intake, controlling pain, and administering medications. A case study is provided.
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PMID:Caring for patients with acute intermittent porphyria. 776 95

All cases of acute intermittent porphyria (AIP) are believed to be caused by a mutation in the gene encoding for porphobilinogen deaminase, a rate-limiting enzyme in the haem synthetic pathway. This gene has been mapped to the long arm of chromosome 11, a region of the genome that has recently attracted considerable attention as a possible location for genes implicated in major mental disorder. This study was designed to show whether major mental illness co-segregated with acute intermittent porphyria in families where the two conditions are found. The study also investigated the relation between clinical mental symptoms and biochemical parameters of acute intermittent porphyria. The case records of 344 consecutive patients admitted to the Porphyrias Research Group in the Western Infirmary in Glasgow between 1950 and 1988 with acute intermittent porphyria were examined for evidence of psychiatric contact. Of 16 individuals identified, 12 were available for the study. Forty relatives of these 12 probands, including 9 who were asymptomatic carriers of AIP, were interviewed for lifetime history of mental illness and current symptoms. Comparisons were made between 4 groups of patients based on urinary porphyrin levels and erythrocyte enzyme activity; 1) manifest acute intermittent porphyria, 2) latent acute intermittent porphyria, 3) normal relatives and 4) total acute intermittent porphyria (latent and manifest combined). No association was found between AIP and schizophrenia or manic-depressive illness. Only one patient with schizophrenia was found in the sample of 344 case notes, and in 2 families bipolar illness was found but did not segregate with acute intermittent porphyria. The commonest psychiatric diagnosis in patients was generalized anxiety.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Acute intermittent porphyria and mental illness--a family study. 802 93

A new form of acute hepatic porphyria with double genetic defect--deficiency of porphobilinogen deaminase and coproporphyrinogen oxidase--is described. Among 17 studied family members this double enzymatic deficiency was found in five individuals, deficiency of porphobilinogen deaminase in four, and deficiency of coproporphyrinogen oxidase in two. Only the proband had an attack of porphyria. Apart from the proband, all family members had normal urinary PBG excretion. Increased faecal coproporphyrin excretion was found in three people. The results obtained suggest that deficiency of porphobilinogen deaminase and coproporphyrinogen oxidase can be inherited independently. coproporphyrinogen oxidase can be inherited independently.
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PMID:Coexistence of hereditary coproporphyria with acute intermittent porphyria. 802 30

The inherited porphyrias are the consequence of inherited deficiencies of enzymes in the heme synthesis pathway; they exhibit classical Mendelian inheritance patterns. The acute porphyrias (acute intermittent, porphyria variegata, hereditary coproporphyria) result from 50% (approx.) deficiencies of specific enzymes, which demonstrate autosomal dominant inheritance. However, only approx. 10% of subjects who inherit a porphyrin enzyme deficiency develop the corresponding acute porphyria and in most instances there is no obvious reason why one patient with an enzyme deficiency is symptomatic whereas another is not. Control of heme synthesis is achieved by the repressor effect of heme on the enzyme ALA synthase. Acute attacks of porphyria can be precipitated in susceptible persons by drugs, ethanol, starvation, hormones, stress and infection. The mechanism is usually by induction of ALA synthase activity. The molecular biology of porphyria variegata and hereditary coproporphyria is large unexplored. Acute intermittent porphyria is due to a partial deficiency of the enzyme porphobilinogen deaminase in the liver. The location of the gene for this enzyme has been identified on the long arm of chromosome 11. Acute intermittent porphyria is a genetically heterogenous disease with the abnormality frequently being a point mutation affecting synthesis of the enzyme.
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PMID:Variable phenotypic expression of genotypic abnormalities in the porphyrias. 822 80

Chester porphyria is a distinct type of acute porphyria, which shows a biochemical overlap with acute intermittent and variegate porphyrias and has a dual enzyme deficiency of porphobilinogen deaminase (PBGD) and protoporphyrinogen oxidase. Linkage analysis in an extensive family with Chester porphyria was undertaken using multiple polymorphic markers. A maximum two point Lod score of 5.25 at 0.07 recombination (confidence interval 0.01 to 0.14) was observed with D11S351, which has been localised to 11q23.1. Multipoint linkage analysis confirmed the two point results and gave a maximum Lod score of 7.33 at a distance less than 1 cM proximal to D11S351. PBGD also maps to 11q but four recombinants could be identified from ten informative meioses in this family using a PBGD DNA polymorphism. Thus, a separate locus on 11q appears to be the basis of Chester porphyria.
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PMID:Evidence for involvement of a second genetic locus on chromosome 11q in porphyrin metabolism. 834 Jan 12


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