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)

In 44 patients with rheumatoid arthritis and 30 control persons, the activities of the following three hemesynthesizing enzymes were determined: delta-aminolevulinic acid dehydratase (D-ALA-D), porphobilinogen deaminase (PBG-D), and ferrochelatase (FCH). Compared with the control persons in patients with rheumatoid arthritis, statistically significant decreased activities of FCH were determined, whereas no differences between the two groups tested occurred with D-ALA-D and PBG-D.
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PMID:[New aspects in the pathogenesis of anemia in chronic polyarthritis]. 29 39

The activities of 5-aminolaevulinate dehydrase (ALA-D), hydroxymethylbilane synthase (HMB-S), uroporphyrinogen III synthase (URO-S) and uroporphyrinogen decarboxylase (URO-D) in the erythrocytes of alcoholics were assayed and compared with those in controls and abstaining alcoholics. The HMB-S and URO-S activities in alcoholics were significantly higher than the controls and there were significant correlations between enzyme activities and mean corpuscular volume (MCV). Alcoholics abstaining from alcohol over a nine-month period showed a return to normal enzyme activities in parallel with the normalization of their MCV. Abstaining alcoholics thus all had normal HMB-S and URO-S activities. The ALA-D and URO-D activities of alcoholics were not significantly different from controls or from abstaining alcoholics. Alcohol appears to have a selective effect on the haem biosynthetic enzymes in the erythron.
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PMID:High performance liquid chromatographic studies of erythrocytes haem biosynthetic enzyme activities in alcoholic macrocytosis. 228 50

Carbamazepine (CBMZP) has been implicated as an inhibitor of the activities of 5-aminolaevulinic acid dehydratase (ALA-D) and uroporphyrinogen I synthetase (URO-S). In an epileptic boy undergoing long-term treatment with valproic acid (VPA), 1.3 g/d, CBMZP, 0.9 g/d and folic acid, 7.5 mg/d, decreased activities of ALA-D and URO-S coincided with increased levels of erythrocyte protoporphyrin (EP) in the absence of Pb poisoning, iron depletion and erythropoietic protoporphyria. A progressive fall in plasma pyridoxal 5'-phosphate (B6-P) to 7.7 nmol/L (lower reference limit, 14.6 nmol/L) prompted implementation of pyridoxine HCl (B6-HCl), 87.5 mg/d followed by administration of both B6-HCl and preformed B6-P (50 mg/d each). This permitted the eventual withdrawal of VPA and a net reduction of CBMZP to 450 mg/d. During these manipulations, ALA-D and URO-S activities, EP and urinary porphyrins and their precursors were measured serially. An assay system utilizing red cell ALA-D for generation of porphobilinogen (PBG) from added ALA at pH 7.4 was used for determination of ALA-D and URO-S activities in separate aliquots of the same assay mixture both in the absence and presence of Zn and dithiothreitol (DTT). One unit (U) for ALA-D = 1 nmol PBG/L RBC/s; for URO-S = 1 nmol porphyrin/L/s; minimum normal level for ALA-D = 135 U; for URO-S = 6 U. B6-HCl alone entailed increases in ALA-D and URO-S prior to any reduction of CBMZP. After administration of both B6-HCl and B6-P and withdrawal of VPA, the overall increase in ALA-D was from 54.59 to 197.2 U (-Zn; -DTT) and from 50.76 to 217.3 U (+Zn; +DTT). The overall increase in URO-S was from 2.67 to 8.90 U (-Zn; -DTT) and from 3.02 to 8.66 U (+Zn; +DTT). During stepwise reduction of VPA, EP remained elevated to values as high as 2.48 mumol/L (upper reference limit, 1.33 mumol/L). Only after permanent withdrawal of VPA did concentrations of EP fall to normal levels. Values for porphyrins and their precursors in urine were normal throughout. Since both VPA and B6-P are strongly protein-bound, it is suggested that VPA displaced B6-P from protective protein binding sites and that the resulting deficit in B6-P (rather than CBMZP) reduced ALA-D and URO-S activities via primary reduction of ALA-synthetase activity. Increases in EP emerge as a hitherto unappreciated effect of VPA warranting further investigation.
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PMID:Protoporphyrinaemia and decreased activities of 5-aminolevulinic acid dehydrase and uroporphyrinogen I synthetase in erythrocytes of a Vitamin B6-deficient epileptic boy given valproic acid and carbamazepine. 250 Feb 71

Some parameters of haem synthesis were estimated in 60 uraemic patients (30 non-dialysed, 30 dialysed) and in 30 matched controls. Serum delta-aminolaevulinic acid and erythrocyte coproporphyrin and protoprophyrin were found significantly higher in the non-dialysed uraemics than in the controls. Erythrocyte delta-aminolaevulinic acid dehydrase (ALA-D) activity was 498 +/- 174 mumol/h.l in the non-dialysed patients, 321 +/- 146 in the dialysed (just before haemodialysis) and 833 +/- 281 in the healthy controls, the differences between these groups all being statistically significant (p less than 0.001). After haemodialysis the enzymic activity in the dialysed group increased significantly (380 +/- 167, p less than 0.001), but remained lower than normal (p less than 0.001). A similar pattern - although with less statistical significance of the differences between groups - was observed concerning erythrocyte uroporphyrinogen I synthase activity. Incubation of normal erythrocytes with uraemic plasma resulted in a considerable decrease of their ALA-D activity (from 830 +/- 263 to 616 +/- 126) while incubation of uraemic erythrocytes with normal plasma increased their ALA-D (from 384 +/- 139 to 494 +/- 77). Addition of zinc in the haemolysate caused a similar induction of ALA-D in both controls and uraemics. The zinc-induced uraemic ALA-D practically reached normal levels. The mechanism of enzymic depression and the possible role of elevated delta-aminolaevulinic acid concentrations (to which depressed ALA-D activity considerably contributes) in the pathogenesis of the neurologic manifestations of uraemia, are discussed.
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PMID:Some parameters of haem synthesis in dialysed and non-dialysed uraemic patients. 285 53

A hemin-permeable hemB mutant had no 5-aminolevulinate dehydratase (ALA D) and extremely low porphobilinogen deaminase (PBG D) activity. When the structural gene for hemB was introduced into this strain on a single-copy plasmid, both activities were observed. When the mutant was grown on PBG, normal PBG D activity was observed. Moreover, a hemA mutant had little or no PBG D activity unless it was grown on ALA or PBG. Neither hemin nor PBG affected the level of PBG D protein produced from in vitro transcription and translation of a plasmid harboring the hemC gene as an insert. We conclude that, in Escherichia coli, PBG availability controls the activity of PBG D at some posttranscriptional level.
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PMID:Availability of porphobilinogen controls appearance of porphobilinogen deaminase activity in Escherichia coli K-12. 304 58

The short-term effects of sodium valproate (VPA) on haem biosynthesis were assessed in a placebo-controlled crossover trial in eight healthy male subjects who ingested VPA 500 mg t.i.d. and matched placebo for 5 days. All showed augmented activity of leucocyte 5-aminolaevulinate synthase (ALA-S) activity, the rate-limiting enzyme of the haem biosynthetic pathway, following 3 and 5 days of VPA treatment (P less than 0.001). This was accompanied by increased urinary excretion of 5-aminolaevulinic acid (ALA; P less than 0.02) and total porphyrins (P less than 0.01). Mean (+/- SD) total VPA concentrations on day 3 (89 +/- 16 mg 1-1) and day 5 (91 +/- 22 mg 1-1) were within the target range for the drug. The long-term effects of VPA administration were examined in epileptic patients on established monotherapy. Leucocyte ALA-S activity (P less than 0.001), and daily urinary excretion of porphobilinogen (P less than 0.01) and total porphyrins (P less than 0.01) were all higher than in age-matched controls. No significant differences in erythrocyte ALA-dehydratase, porphobilinogen deaminase and uroporphyrinogen decarboxylase activities were found between the groups. These data suggest that VPA is porphyrinogenic in man and cannot be recommended as safe for seizure management in the porphyric patient.
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PMID:Effects of sodium valproate on haem biosynthesis in man: implications for seizure management in the porphyric patient. 313 Feb 56

The activities of 5 enzymes of the haem biosynthetic pathway and the protoporphyrin concentrations have been measured in peripheral red blood cells of 23 patients having a preleukaemic syndrome with refractory sideroblastic anaemia. A decreased delta-aminolaevulinic acid synthase (ALA-S) activity, an increased uroporphyrinogen I synthase activity and an increased red cell protoporphyrin concentration were consistent findings. Patients with abnormal leucocyte and/or platelet counts in the peripheral blood as well as patients with an excess of blast cells in the bone marrow had the lowest ALA-S activities. A further decrease in ALA-S activity was observed in 3 patients after leukaemic change in the disease. Patients having cytogenetic abnormalities showed no unique enzyme abnormalities. These results indicate that enzymatic disturbances of haem synthesis cannot be used as prognostic indicator of leukaemic transformation in refractory sideroblastic anaemia, but a very low ALA-S activity appears to accompany the development of a leukaemia in such patients.
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PMID:Haem biosynthesis in refractory sideroblastic anaemia associated with the preleukaemic syndrome. 733 57

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

Three patients from Moroccan kindreds with acute intermittent porphyria (AIP) are described. The propositus of family A originating from Mrirt, Morocco, is living in Embrun, France. This 26 year-old woman who experienced an acute attack with visceral manifestations presented an elevated urinary level of 5-ALA and PBG, and a half-normal activity in porphobilinogen deaminase (PBG-D) in red blood cells (RBC). The family's survey was carried out by measuring the PBG-D activity in RBC (normal values = 125 +/- 40 U). Three of the 16 subjects tested, beside the propositus, were found to be asymptomatic carriers (PBG-D < 70 U). The two patients of family B, originating from Tetouan in the Rif area, were living in Bastia, Corsica. The two brothers, respectively 37 and 39 years old, had a long history (6 years) of neuropsychiatric manifestations before the AIP diagnosis was evidenced by elevated urinary level of 5-ALA and PBG, and showed a partial deficiency, approximately, 50%, of PBG-D activity in RBC. The youngest patient also presented a peripheral neuropathy and recently died after surgery from an unknown reason at the age of 45.
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PMID:[Acute intermittent porphyria in 2 Moroccan families. Clinical and biological study]. 875 36

The effect of beryllium (Be) compounds on porphyrins was investigated in pregnant mice. The blood protoporphyrin (Proto) and zinc protoporphyrin (Zn Proto) concentrations were increased in pregnancy. Regardless of pregnancy or nonpregnancy, the Proto concentration was decreased after Be injection. Delta-aminolevulinic acid dehydratase (ALA-D) and porphobilinogen deaminase (PBG-D) activities in blood were significantly elevated in the pregnant untreated (Con-pregnant) group, compared to the nonpregnant mice untreated (Con-nonpregnant) and nonpregnant mice treated with Be (Be-nonpregnant) groups. The blood ALA-D activity of the pregnant mice treated with Be (Be-pregnant group) tended to decrease, compared to Con-pregnant group. The blood PBG-D activity in the Be-pregnant group was significantly lower compared with that of the Con-pregnant group. The ALA-D and PBG-D activities in the spleen were also significantly elevated in the Con-pregnant group, compared to nonpregnant groups. However, it was noted that these values in the Be-pregnant group were almost the same as that of the Con-nonpregnant group and were significantly lower than that in the Con-pregnant group. The elevation of ALA-D and PBG-D activities in the blood and spleen, which play a role in the hematopoietic function of mice, was observed in the Con-pregnant mice compared to the nonpregnant mice. However, the phenomenon was not observed in the Be-pregnant mice, it suggesting that Be suppressed the pregnancy-induced increase in hematopoietic function.
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PMID:Effect of beryllium chloride on porphyrin metabolism in pregnant mice administered by subcutaneous injection. 914 Apr 67


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