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At least 19 recordsLinked to original sources
PubMed1977

Production of copper coproporphyrin III by Bacillus cereus. II. Regulation of the biosynthesis of coproporphyrin III and its copper complex by oxygen and heavy metal ions.

The effects of oxygen and heavy metal ions on the production of copper coproporphyrin III were studied in Bacillus cereus strain 2. The formation of copper coproporphyrin III was found to be maximum when the cells were cultivated in G-medium at a low level of oxygen supply, but it was suppressed at extremely low oxygen supply levels. When the cells were cultured in metal-free G-medium, neither metal-coproporphyrin III nor coproporphyrin III was formed. In the presence of copper in the medium (400-100 micrometers), the formation of coproporphyrin III copper salt was maximum, but the addition of various heavy metal ions other than copper to the copper-free medium resulted in the formation of neither coproporphyrin III nor its metal chelates. Copper ions appear to be specifically required for coproporphyrin III formation.

Bacillus cereus↗
PubMed1976

Coproporphyrin isomers in Dubin-Johnson syndrome.

To shed light on the nature of abnormal porphyrin metabolism in Dubin-Johnson syndrome (DJS), coproporphyrin isomer distribution in urine and bile was investigated in carriers and patients with DJS selected from among the families in the cluster area of the syndrome in Japan. Urinary total coproporphyrin content in patients with DJS exceeded that of normal controls (P less than 0.01). However, the increase in urinary excretion of total coproporphyrin was of a much lesser degree compared to a remarkable increase in urinary total coproporphyrin reported for erythropoietic porphyria in which a deficiency of uroporphyrinogen III cosynthetase had been demonstrated. Urinary total coproporphyrin content in carriers was significantly smaller than that of normal controls (P less than 0.05). This paradoxical decrease of urinary total coproporphyrin concentration in DJS carriers was observed in consequence of a decrease in coproporphyrin III excretion without concomitant increase in type I isomer. Administration of griseofulvin, in the dose which had been shown to precipitate attacks of acute porphyria in susceptible subjects, to carriers and patients with DJS did not elicit clinical signs suggestive of porphyria, and urinary total coproporphyrin concentration and the percentage of coproporphyrin I remained unchanged. These results were interpreted to demonstrate an aspect of DJS that was not consistent with the hypothesis that a partial defect in uroporphyrinogen III cosynthetase of the liver might be the cause of DJS. Coproporphyrin in the bile of DJS patients was preponderantly type I.

Bile↗
PubMed1982

Urinary coproporphyrin excretion in Rotor's syndrome: a family study.

A family of seven is described in which a teenage boy and two siblings were found to have Rotor's syndrome. Total urinary coproporphyrin excretion was found to be significantly elevated in the patients with Rotor's syndrome (mean 59 . 0 mumol/mol creatinine), when compared with control subjects (mean 16 . 3 mumol/mol creatinine) (p less than 0 . 005). Similarly, urinary excretion of both coproporphyrin isomer I and coproporphyrin isomer III was greater in the subjects with Rotor's syndrome than in controls (p less than 0 . 005). Coproporphyrin I comprised 60 . 2% of total urinary coproporphyrin excretion in the subjects with Rotor's syndrome, compared with 38 . 6% in the controls, but the difference was not significant. In the parents and clinically unaffected siblings neither total urinary coproporphyrin excretion (13 . 3 and 19 . 3 mumol/mol creatinine respectively) nor percentage coproporphyrin I excretion (36 . 8 and 30 . 4%) differed from controls. Thus, although we have confirmed the previous finding of increased urinary coproporphyrin excretion in subjects with Rotor's syndrome, we have not found the previously noted intermediate increase in coproporphyrin I excretion amongst phenotypically normal relatives of subjects with this autosomal recessive disorder.

Adolescent↗
PubMed1988

[Renal and enteral elimination of coproporphyrin isomers in Rotor's syndrome. A family study].

Urinary and fecal total, isomer I, and isomer III coproporphyrin excretion of a Rotor's syndrome patient and his family were determined. The propositus showed increased urinary total coproporphyrin excretion (248 micrograms/24 h) and a shift of the coproporphyrin isomer I/III relation (70%/30%). The propositus's father and two siblings also had elevated renal excretion of coproporphyrin I. Total coproporphyrin excretion was enhanced only in the propositus's father and one sibling, while being normal in another sibling. All family members that could be investigated showed considerably decreased fecal porphyrin excretion. In Rotor's syndrome porphyrin excretion is mainly renal. The coproporphyrin isomer I/III relation is shifted towards isomer I. Phenotypically normal relatives with normal bilirubin plasma levels may have alterations in both their renal and enteral coproporphyrin excretion.

Adult↗
PubMed1999

Investigations on the formation of urinary coproporphyrin isomers I-IV in 5-aminolevulinic acid dehydratase deficiency porphyria, acute lead intoxication and after oral 5-aminolevulinic acid loading.

OBJECTIVES: Investigation of the metabolism of the four urinary coproporphyrin isomers I-IV in the extremely rare 5-aminolevulinic acid dehydratase (ALAD) deficiency porphyria (syn.: Doss porphyria), in acute lead intoxication, and after oral 5-aminolevulinic acid (ALA) loading. DESIGN AND METHODS: We analyzed the excretion of total urinary coproporphyrins and the composition of the respective isomers I-IV with ion-pair HPLC methods in these conditions. RESULTS: The concentration of total coproporphyrins was about 30-fold increased in patients with ALAD deficiency porphyria and acute lead intoxication as compared with controls. In addition, the proportion of coproporphyrin III as well as that of the atypical isomers II and IV were significantly elevated at the expense of isomer I. After oral ALA administration to normal volunteers, a 10- to 15-fold increase in the maximal concentration of total urinary coproporphyrins was observed within 12 to 24 h. Urinary levels were back to normal after another 24 h. The excretion pattern of the individual urinary coproporphyrin isomers I-IV after ALA ingestion revealed a dynamic process: initially isomer III was preferentially formed, followed by a 3-fold increase of isomers II and IV via non-enzymatic rearrangement of isomer III, and finally normalization of all four isomers occurred within 48 h. CONCLUSIONS: These results demonstrate that oral ALA loading can be used as an in vivo model to study the metabolism of the four urinary coproporphyrin isomers I-IV especially in ALAD deficiency porphyria and in acute lead poisoning.

Administration, Oral↗
PubMed1983

Urinary coproporphyrin in lead intoxication: a study in the rabbit.

Lead acetate was administered to adult New Zealand White rabbits in their drinking water. Their mean blood lead level rose to 4.5 mumol/l within a week and then remained relatively constant. The rabbits developed a marked coproporphyrinuria. Plasma levels of coproporphyrin increased but not in proportion to the urine excretion. Thus the renal clearance of coproporphyrin rose from a mean of 1.8 ml/min to 32.2 ml/min whilst creatinine clearance remained constant. The concentration of coproporphyrin in renal venous blood from control rabbits was found to be slightly lower than that in arterial blood. In the lead intoxicated rabbits the concentration of coproporphyrin in renal venous blood was approximately three times higher than the arterial concentration. Significantly higher levels of lead, porphobilinogen, uroporphyrin, coproporphyrin and protoporphyrin were found in renal tissue than in brain, heart or liver. Renal tissue homogenates from control rabbits were able to synthesize porphobilinogen, uroporphyrin, coproporphyrin and protoporphyrin when incubated with 5-aminolaevulinic acid. Renal tissue from lead intoxicated rabbits was also able to synthesize these haem precursors although at a reduced rate. Three enzymes from the haem biosynthetic pathway were assayed in renal mitochondria. Compared with those from controls, mitochondria from lead intoxicated rabbits showed no significant difference in ferrochelatase activities, but the activities of coproporphyrinogen oxidase were decreased, and those of 5-aminolaevulinate synthase were increased. It was concluded that a large portion of the excess coproporphyrin excreted by the lead intoxicated rabbits was of renal origin.

Animals↗
PubMed1993

Composition of urinary coproporphyrin isomers I-IV in human porphyrias.

The urinary distribution and relative proportions of the four coproporphyrin isomers I-IV were investigated in 50 patients suffering from hepatic and erythropoietic types of hereditary porphyrias. A highly efficient sample preparation method was applied to isolate urinary coproporphyrins, the isomer ratios of which were quantitated by isocratic ion-pair high-performance liquid chromatography. Results showed a significant decrease (p < 0.001) of the proportion of coproporphyrin I in acute hepatic porphyria (acute intermittent porphyria, hereditary coproporphyria, variegate porphyria, porphobilinogen synthase deficiency porphyria) as compared with chronic hepatic porphyria (porphyria cutanea tarda, chronic hepatic porphyria type B and C) (13.2 +/- 5.3%, mean +/- S.D., vs. 31.4 +/- 11.5%). Conversely, the proportion of isomer III was significantly higher (p < 0.001) in acute hepatic porphyria than in chronic hepatic porphyria (80.9 +/- 5.2% vs. 62.2 +/- 10.9%). As expected, the highest level of coproporphyrin I (90.0 +/- 1.9%) was found in congenital erythropoietic porphyria. The atypical coproporphyrins II and IV were detected in all types of porphyria analysed and ranged from 0.2 to 9.0%; no significant differences were seen between acute and chronic hepatic porphyrias. The diagnostic importance of the isomer ratios of coproporphyrins I and III has been confirmed in our study, while the significance of the atypical coproporphyrin isomers II and IV is still unclear at present.

Adult↗
PubMedDate not supplied

Urinary coproporphyrin isomers in Rotor's syndrome: a study in eight families.

Urinary coproporphyrin isomers were measured in 17 patients with Rotor's syndrome, 65 phenotypically normal relatives of 14 patients from eight families, and 21 normal subjects. coproporphyrin I was elevated in Rotor's syndrome (p less than 0.001) and, to a lesser degree, in phenotypically normal parents (p less than 0.005), children, and siblings (p less than 0.025) as compared to normal controls. Coproporphyrin III in patients, parents, and children did not differ from that in normal controls. Genetic analysis was consistent with transmission of Rotor's syndrome as an autosomal recessive trait with respect to urinary excretion of coproporphyrin I. After i.v. injection of delta-aminolevulinic acid, urinary coproporphyrin I increased to a similar extent in Rotor's syndrome and in normal subjects; urinary coproporphyrin III excretion was less in Rotor's syndrome than in normal subjects.

Adult↗
PubMedDate not supplied

Faecal and urinary coproporphyrin isomers in biliary atresia and neonatal hepatitis.

Based on the assumption that faecal and urinary coproporphyrin excretion is closely dependent on biliary function, coproporphyrin excretion was investigated in severe cholestatic diseases in infants and adults. The following subjects were investigated: biliary atresia (5), neonatal hepatitis (3), normal infants (11), adults with biliary obstruction (5) and normal adults (18). Urinary and faecal coproporphyrin concentrations were determined by solvent partition methods, and the isomers (I and III) were separated by thin-layer chromatography with direct spectrofluorometric scanning. The results showed a significant increase in urinary coproporphyrin in biliary atresia and neonatal hepatitis and in adults with biliary obstruction. All the cholestatic diseases showed the same marked increase in urinary isomer I. In biliary atresia and neonatal hepatitis there was a significant decrease in faecal coproporphyrin and a concomitant increase in isomer III (of bacterial origin) which was related to the extent of the biliary defect. Determination of urinary and faecal coproporphyrin, and particularly of the isomer distribution, may be a sensitive tool for diagnosis.

Adult↗
PubMed1995

Excretion pattern of faecal coproporphyrin isomers I-IV in human porphyrias.

The relative proportions of the four coproporphyrin isomers I-IV were analysed in faeces of 20 healthy subjects and 60 patients suffering from one of the seven common types of hepatic or erythropoietic hereditary porphyrias. A newly developed, reliable method for sample preparation was applied, using reversed-phase thin layer chromatography for the isolation of naturally occurring coproporphyrin free carboxylic acids. Accurate separation and quantitation of the individual isomers I-IV were achieved with the help of ion-pair high-performance liquid chromatography. The four coproporphyrin isomers I-IV were positively identified by on-line scanning of their fluorescence spectra in the emission and excitation modes. Recovery rates with this new analytical procedure were between 90 and 100%, and coefficients of variation varied between 0.8 and 5.7% (N = 7). Diagnostically important findings were greatly increased proportions of isomer I and decreased proportions of isomers III, II and IV in erythropoietic porphyrias, such as congenital erythropoietic porphyria and protoporphyria. Significantly increased proportions of isomers III, II and IV, on the other hand, were observed in acute hepatic porphyrias, e.g. acute intermittent porphyria and porphobilinogen synthase deficiency porphyria, as compared with porphyria cutanea tarda (p < 0.005 and p < 0.03, respectively). Inversion of the faecal coproporphyrin III to I ratios and markedly elevated percentages of the atypical isomers II and IV were important diagnostic markers for variegate porphyria and hereditary coproporphyria. The highest proportions of isomer III were found in hereditary coproporphyria, where the amount of the isomers II and IV exceeded that of isomer I. Asymptomatic carriers of the relevant gene defect in families with hereditary coproporphyria could be detected by an increased faecal coproporphyrin III to I ratio. Our results clearly demonstrate the potential of faecal coproporphyrin I-IV isomer ratios for the diagnosis and differential diagnosis of hereditary porphyrias.

Adult↗
PubMed1983

Liquid-chromatographic separation and determination of coproporphyrins I and III in urine.

We describe a method of determining coproporphyrin I, III, and I plus III in urine by "high-performance" liquid chromatography. Urine is simply injected after dilution with an equal volume of glacial acetic acid. Some urinary coproporphyrin apparently binds zinc without acetic acid treatment. The working linear range of coproporphyrin concentrations is 10 to 2000 micrograms/L of urine. The sensitivity of the method is sufficient to detect as little as 10 micrograms of coproporphyrins per liter of urine. Analytical recoveries for both coproporphyrins were 96.7-106%. Results by the present method and those by an extraction method (Br J Ind Med 31:72-74, 1974) correlate well (r = 0.975). Mean (and range) coproporphyrin I, III, and I plus III concentrations in urine from normal subjects are 33.7 (7-75), 28.6 (0-130), and 62.2 (7-174) micrograms/L, respectively.

Acetates↗
PubMed1976

Multicompartment analysis of 14C-labelled coproporphyrin and uroporphyrin kinetics in human beings.

14C-labelled coproporphyrin I and III and uroporphyrin I were injected intravenously into healthy human subjects. Two experiments were performed with each porphyrin. Counting of blood, urine and faeces was made as a function of time. The coproporphyrin data were simulated by means of an analogy computer by using a four-compartment model with a delay pool. The physiological counterparts to the compartments were considered to be liver, blood and gut. From the blood radioactivity disappearance curve of uroporphyrin three exponential components could be worked out. The least square method was used for the solution of the plasma and urine radioactivity curves. A three-compartment model was constructed to illustrate the kinetics of uroporphyrin I. Coproporphyrin I and III behaved essentially similarly, whilst the kinetic behaviour of uroporphyrin I was completely different from that of coproporphyrins. A rapid hepatic uptake, preferential faecal excretion and a significant enterohepatic circulation were features of coproporphyrin kinetics. Over 70 per cent of the tracer activity of uroporphyrin I was found to accumulate to a rather large pool (volume 16--28 times the plasma volume) from where the back flow to plasma was rather slow. Practically all the uroporphyrin was excreted via urine.

Adult↗
PubMed1991

[Determination of coproporphyrin in urine].

Methods for urinary coproporphyrin measurements are analyzed. Data obtained by two methods, spectrophotometry and fluorescent method, are presented, the advantages and shortcomings of both are discussed. The authors recommend the fluorescent technique as a universal rapid method for wide medical practice. The problem of the units of coproporphyrin measurement is also discussed. The authors suggest replacing measurements per g of creatinine or daily portion by estimation of the coproporphyrin index in the morning portion of the urine. Study of the effects of various factors (climatic conditions, nutrition, patient's age and sex) on normal coproporphyrin excretion from the body has demonstrated that these factors do not noticeably influence porphyrin metabolism; for normal subjects the coproporphyrin index varies from 30 to 110 micrograms/day.

Adult↗
PubMedDate not supplied

[Fluorescent immunoanalysis. Synthesis, spectro-fluorescent and immunologic properties of conjugates of coproporphyrin I with antibodies].

The synthesis of protein conjugates with the new high-efficient fluorescent labile coproporphyrin-I was optimized. A number of conjugates of monoclonal antibodies with different coproporphyrin-I content were synthesized, and their spectral properties were studied in water and micellar solutions, i.e. adsorption, excitation and emission spectra, fluorescence quantum yields, fluorescence pH-dependences. The binding constants of coproporphyrin-I and its protein conjugates with serum albumin were determined. The antibodies labelled with coproporphyrin-I retain the functional activity and photochemically stable in water solutions. The sensitivity of fluorometric detection of coproporphyrin-I and its conjugates with proteins is more than 10 times greater than in case of FITC.

Animals↗
PubMed1978

Copper coproporphyrin excretion in familial coproporphyria.

Analysis of stool specimens from a patient with familial coproporphyria by high-performance liquid chromatography revealed that 112 microgram per gram of dry feces (14% of the total porphyrin present) was copper coproporphyrin. Examination of stool specimens from other patients with this disease confirmed the presence of significant amounts of both copper coproporphyrin and coproporphyrin. Further investigation showed that the copper coproporphyrin was probably formed by a nonenzymic incorporation of copper by the coproporphyrin in either the bile or feces.

Adolescent↗
PubMed1990

Cutaneous photosensitivity and coproporphyrin abnormalities in the Alagille syndrome.

Porphyria cutanea tarda-like blistering, fragility, and scarring of light-exposed skin was observed in four children with the Alagille syndrome. Abnormally elevated levels of serum porphyrins, of which coproporphyrin isomers I and III together accounted for 50%-89% of the total, were found in these four children but also in three other children with the Alagille syndrome without such skin lesions. The ratio for isomer I to III for total serum coproporphyrin concentration was determined in six cases; the concentration of isomer I was greater than or equal to that of isomer III in each case. Urinary total porphyrin excretion was found to be elevated in six of the seven cases, with 72% +/- 8% occurring as coproporphyrins I and III. The ratio for urinary coproporphyrin I to III was greater than or equal to 1 in six of these patients, the reverse of the typical normal isomer distribution. Inasmuch as the presence or absence of photocutaneous lesions did not correlate with levels of porphyrins in serum or urine, other factors may be involved in the pathogenesis of the skin lesions.

Adolescent↗
PubMed1989

Isocratic ion-pair high-performance liquid chromatographic methods for the determination of uroporphyrin and coproporphyrin type II and IV isomers in human urine.

Urinary porphyrins of porphyric patients were isolated as their methyl esters by using a simple, modified thin-layer chromatographic system. Existing methods for the isocratic ion-pair high-performance liquid chromatographic separation of uroporphyrin and coproporphyrin isomers were decisively improved by elevating the column temperatures, changing the types of columns used and modifying the eluent compositions. These techniques were applied to the determination of the isomeric distribution of uroporphyrins and coproporphyrins isolated from urines of patients in the acute or latent phase of acute intermittent porphyria. In these urines relatively high contents of the atypical uroporphyrins II (2-5%) and IV (13-19%) were found. The coproporphyrin fractions contained significantly smaller amounts of the atypical isomers II (1-2%) and IV (2-5%), the presence of which was demonstrated for the first time in such urines. Several mechanisms for the formation of the atypical coproporphyrin isomers are discussed. The isocratic ion-pair separation method served also to control the isomeric purity of uroporphyrin specimens of both natural and synthetic origin.

Chromatography, High Pressure Liquid↗