Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0002871 (anemia)
 52,094 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The etiology of anemia in cancer is not fully understood. A possible cause of the anemia of tumor-bearing animals could be a decreased activity in the enzymes of the heme-pathway. We report the enzyme activity of porphobilinogen-synthetase in the liver of Yoshida sarcoma-bearing rats. PBG-synthetase activity in the whole liver, is higher in tumor-bearing rats than in controls, although the enzyme activity by a gram of wet liver is decreased. Hence PBG-synthetase activity is not a limiting factor in the biosynthesis of heme in tumor-bearing animals.
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PMID:PBG-synthetase activity in the liver of Yoshida sarcoma-bearing rats. 48 94

Normal or increased amounts of series III porphyrins with greater amounts of series I were observed on incubation of PBG in hemolysates of congenital erythropoietic porphyria vs. normal erythrocytes, human or bovine. Correlation with reticulocyte percentage was poor, in the aggregate a general trend toward increased values of both isomers I and III was noted with increasing reticulocytes. When the percent of type III was low the net amount was increased as compared with normal. Hemolysates of non-porphyric, reticulocyte-rich red cells (hemolytic or posthemorrhagic anemia) formed only minute amounts of type I porphyrin but at the same time no more, or even less type III than the porphyric hemolysates, although representing red cells of greater reticulocyte content. No evidence of deficient heme synthesis was observed in porphyric hemolysates incubayed with [14C]-porphobilinogen or 59Fe. Other studies of porphyric hemolysates incubated with and without added mouse spleen synthetase failed to reveal evidence of an absolute UPG-III cosynthetase (Co-S) deficiency. The large increases of type I porphyrin with normal or increased formation of type III, both in the disease and in the hemolysates, are believed due to a primary increase of ALA-S or UPG-S activity rather than a decrease of Co-S. Possible mutations which might be responsible for this increase are considered.
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PMID:The activities of uroporphyrinogen synthetase and cosynthetase in congenital erythropoietic porphyria (CEP). 98 34

Porphyrin metabolism disorders are grouped into three classes. 1) Hereditary porphyrias including those caused by an inherited deficiency in one of the enzymes responsible for porphyrin synthesis. 2) Secondary porphyrias: well defined clinical situations due to disturbed porphyrin metabolism caused by a variety of toxic substances or drugs or secondary to other pathological conditions. 3) porphyrin metabolism disorders as concomitant featured of certain types of poisoning or particular pathologies. This is followed by a brief description of porphyrin synthesis and the enzymes involved in it, and the distribution of porphyrins and their precursors in certain tissues and biological materials. Hereditary porphyrins are treated individually and not classified since all the classification systems proposed are open to criticism. However the value of grouping acute intermittent porphyria, hereditary coproporphyria, variegated porphyria and the porphyria caused by PBG-synthetase deficiency under "acute porphyrias" is recognised since all involve acute attacks with similar symptoms and prognoses, all are triggered by the same factors and all are treated in the same way. The various forms of hereditary porphyrias are grouped into 3 main categories: a) acute attacks featuring abdominal colics and signs of distress on the cerebral and peripheral nervous systems; b) skin alteration due to photosensitisation; c) haemolytic anaemia. Treatment is divided into preventive, symptomatic and aetiopathogenic. The individual hereditary porphyrias are then examined. The secondary porphyrias examined include lead poisoning, porphyria of the skin caused by hexachlorobenzene, subacute or chronic tyrosinaemia and acute intermittent porphyria caused by carbamazepine. Finally the porphyrin metabolism disorders concomitant with other diseases are examined including those encountered in anaemia, liver disease, dermatological conditions and infections and conditions caused by drugs and toxic substances.
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PMID:[Clinical medicine of disorders of porphyrin metabolism in man]. 331 15

Unexpected differences in clinical and biochemical findings in two brothers occupationally exposed to the same source of lead for dissimilar lengths of time are presented. Only the brother with the shorter period of lead exposure was anemic and afflicted by nausea, vomiting, abdominal colic and arthralgia. His urinary PBG output yielded the high orders of magnitude found in acute intermittent porphyria in relapse. Prior to administration of a single dose of EDTA (1 g of the calcium disodium salt given intravenously in 325 mL 0.15 mol/L NaCl), his blood lead levels averaged 3.6 mumol/L. The amount of chelatable lead retrieved from his urine, 31 mumol/day, was more than twice that found in his asymptomatic counterpart who was exposed to lead for 13 months and whose pre-EDTA blood lead levels averaged 4.0 mumol/L. Not only the activity of delta-aminolaevulinic acid dehydratase, but also that of uroporphyrinogen I synthetase, was markedly inhibited by lead in red cells of both brothers. These activities were restored to normal levels in vitro by addition to the assay system of zinc and dithiothreitol. This ruled out a coexisting genetic deficiency of either enzyme. The anemia of the symptomatic brother with the shorter period of lead exposure was alleviated by folic acid, 15 mg/day. The differences in findings between the two brothers point to differential susceptibility to lead and illustrate the extent to which symptomatic lead poisoning may mimic biochemical and clinical features of the acute porphyrias.
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PMID:Occupational lead exposure: studies in two brothers showing differential susceptibility to lead. 401 20

For several years, a 4-12-fold increase of the upper normal limit in erythrocyte protoporphyrin concentrations persisted in two men 34 and 39 years of age who were chronically exposed to lead. We are dealing with a zinc protoporphyrinemia in both cases, without lead intoxication or anemia. The 34-year-old had been a regular blood donor for 10 years and had already been treated for iron deficiency several times. Hemoglobin, red cell counts, hematocrit, and iron were at the lower normal limit. The activity of porphobilinogen synthase (PBG-S), uroporphyrinogen-synthase and -decarboxylase as well as urinary porphyrin precursors and porphyrin excretion were normal. Protoporphyrinemia was said to be due to a prelatent/latent iron deficiency. In the 39-year-old, the activity of PBG-S was lowered to 388 mumol/1 . h, as compared to the mean of controls (1,190 +/- 210, x +/- SD, n = 50), in connection with a slightly elevated excretion of delta-aminolevulinic acid and coproporphyrin in the urine and a high-normal blood lead level. In his family there was no history of either a protoporphyrinemia or a hematological disturbance. Six of eight family members in three generations showed a diminished activity of PBG-S: 600 +/- 160, P less than 0.001 compared to controls. These family members are heterozygous with regard to the PBG-S deficiency; they are clinically unobtrusive in comparison to homozygotes with an acute prophyria syndrome. Activation by zinc and reactivation by dithiothreitol were normal in contrast to PBG-S from patients with lead intoxication. The cause of biochemical symptoms of subclinical lead intoxication developed by the propositus is probably due to the hereditary PBG-S deficiency which sensitizes him to low-level lead exposure. The determination of red cell PBG-S activity can be recommended as a test detecting heterozygotes. The hereditary PBG-S deficiency is recognized as a new molecular basis for the pathogenesis of lead intoxication.
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PMID:Persistent protoporphyrinemia in hereditary porphobilinogen synthase (delta-aminolevulinic acid dehydrase) deficiency under low lead exposure. A new molecular basis for the pathogenesis of lead intoxication. 710

Patients with iron deficiency anemia (IDA) were examined as well as patients with active lymphoma with low serum iron (SI) and anemia prior to treatment. Increased content of reduced glutathione (GSH) was found in the patients with IDA as well as enhanced activity of PBG-S in erythocytes, in parallel with the decreased SI and saturation rate of transferrins (SRT) and enhanced total iron-binding capacity (TIBC) in serum. In lymphoma patients a normal GSH content is found as well as normal PBG-S activity in erythocytes, low content of iron, SRT level and decreased TIBC in serum. The connection of SH groups with the level of serum iron is discussed.
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PMID:[Reduced glutathione and porphobilinogen synthase activity in the erythrocytes of anemic patients with low serum iron]. 714 24