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In this study, an on-line stacking capillary electrophoresis (CE) method, reverse-mode field amplified sample injection equipped with sweeping micellar electrokinetic chromatography (RMFASI-sweeping MEKC), was established for direct determination of uroporphyrin and coproporphyrin in human urine. Porphyrins playing a very important role in the biosynthesis of heme, chlorophyll and other important enzymes are a series of important molecules in organism. Therefore, determination of porphyrin metabolites, uroporphyrin and coproporphyrin, was very important for clinical survey of some diseases. In this study, the urine sample after simple dilution could be directly analyzed by this on-line stacking CE method. The optimal CE separation buffer was 70 mM phosphate buffer at pH 3. Before sample injection, a water plug was introduced (2.5 psi for 10s), and then the samples were loaded by electrokinetic injection (-10 kV, 200 s). Finally, the phosphate buffer (70 mM, pH 3) containing 100mM SDS was served as the sweeping buffer to stack and separate the analytes at -20 kV. The calibration curves were linear over a range of 15-200 ng/ml for uroporphyrin, and 300-1000 ng/ml for coproporphyrin. The coefficient of correlation (r) in intra-batch (n=5) and inter-batch (n=5) analysis was above 0.983. The LODs (S/N=3) were 5 ng/ml for uroporphyrin, and 100ng/ml for coproporphyrin. The absolute values of relative standard deviation (RSD) and relative error (RE) in intra-batch (n=5) and inter-batch (n=5) assays were less than 8.6% showing the good precision and accuracy. The stacking method was successfully applied in real urine sample and feasible for serving as a tool for detection of uroporphyrin and coproporphyrin in clinical., (Copyright © 2015 Elsevier B.V. All rights reserved.)

A simple and rapid spectrofluorimetric method is described for the determination of the closely overlapping mixture of coproporphyrin (CP) and uroporphyrin (UP) in urine samples. Matrix Isopotential Synchronous Fluorescence Spectrometry (MISFS) was applied to improve the spectral resolution for the severely overlapped spectra of the urinary porphyrins. First-order derivative technique eliminates the background interference of each component on the other. Using these two techniques together, selectivity was improved, while maintaining a high sensitivity, and time-consuming separation processes and multiple scanning processes were avoided. The limits of detection were 0.15 nmol L(-1) and 0.1 nmol L(-1) for CP and UP, respectively. The concentrations of CP and UP were determined from the peak amplitudes of the Derivative Matrix Isopotential Synchronous Fluorescence (DMISF) spectra, at their detection points where the interference was suppressed. Porphyrins excretion in urine samples, collected from normal subjects, was studied. A comparison between the new method and the anion-exchange chromatographic method of Martinez and Mills was established using Bland-Altman method and the results indicate that these two methods are in a good agreement with each other., (2010 Elsevier B.V. All rights reserved.)

Human acute intermittent porphyria (AIP), the most common acute hepatic porphyria, is an autosomal dominant inborn error of heme biosynthesis due to the half-normal activity of hydroxymethylbilane synthase (HMB-synthase). Here, we describe the first naturally occurring animal model of AIP in four unrelated cat lines who presented phenotypically as congenital erythropoietic porphyria (CEP). Affected cats had erythrodontia, brownish urine, fluorescent bones, and markedly elevated urinary uroporphyrin (URO) and coproporphyrin (COPRO) consistent with CEP. However, their uroporphyrinogen-III-synthase (URO-synthase) activities (deficient in CEP) were normal. Notably, affected cats had half-normal HMB-synthase activities and elevated urinary 5-aminolevulinic acid (ALA) and porphobilinogen (PBG), the deficient enzyme and accumulated metabolites in human AIP. Sequencing the feline HMB-synthase gene revealed different mutations in each line: a duplication (c.189dupT), an in-frame 3 bp deletion (c.842&#95;844delGAG) identical to that causing human AIP and two missense mutations, c.250G>A (p.A84T) and c.445C>T (p.R149W). Prokaryotic expression of mutations c.842&#95;844delGAG and c.445C>T resulted in mutant enzymes with <1% wild-type activity, whereas c.250G>A expressed a stable enzyme with approximately 35% of wild-type activity. The discolored teeth from the affected cats contained markedly elevated URO I and III, accounting for the CEP-like phenocopy. In three lines, the phenotype was an autosomal dominant trait, while affected cats with the c.250G>A (p.A84T) mutation were homozygous, a unique recessive form of AIP. These animal models may permit further investigation of the pathogenesis of the acute, life-threatening neurological attacks in human AIP and the evaluation of therapeutic strategies. GenBank Accession Numbers: GQ850461-GQ850464.

Changes in urinary porphyrin excretion may be the result of hereditary causes and/or from environmental or occupational exposure. The objective of this study was to measure the amount of some porphyrins in spot urine samples obtained from volunteers randomly selected from a healthy adult population of São Paulo with a sensitive HPLC method and to estimate normal ranges for a non-exposed population. Spot urine samples were collected from 126 subjects (both genders, 18 to 65 years old) not occupationally exposed to porphyrinogenic agents. Porphyrin fractions were separated on RP-18 HPLC column eluted with a methanol/ammonium acetate buffer gradient, pH 4.0, and measured fluorometrically (excitation 405 nm/emission 620 nm). The amount of porphyrins was corrected for urinary creatinine excretion. Only 8-carboxyl (uro) and 4-carboxyl (copro) porphyrins were quantified as microg/g creatinine. Data regarding age, gender, occupational activities, smoking and drinking habits were analyzed by Mann-Whitney and Kruskal-Wallis tests. Uroporphyrin results did not differ significantly between the subgroups studied. Copro and uro + copro porphyrins were significantly different for smokers (P = 0.008) and occupational activities (P = 0.004). With respect to alcohol consumption, only men drinking >20 g/week showed significant differences in the levels of copro (P = 0.022) and uro + copro porphyrins (P = 0.012). The 2.5-97.5th percentile limit values, excluding those for subjects with an alcohol drinking habit >20 g/week, were 0-20.8, 11.7-93.1, and 15.9-102.9 microg/g creatinine for uro, copro and uro + copro porphyrins, respectively. These percentile limit values can be proposed as a first attempt to provide urinary porphyrin reference values for our population, serving for an early diagnosis of porphyrinopathies or as biomarkers of exposure to porphyrinogenic agents.

Background: Porphyria cutanea tarda (PCT) is a metabolic disease characterized by vesicles and blisters in sun-exposed areas and scleroderma-like lesions in sun-exposed and non-sun-exposed areas. Mast cells participate in the pathogenesis of bullous diseases and diseases that show sclerosis, including PCT. Moreover, transforming growth factor-beta (TGF-beta) is the main cytokine in the development of tissue sclerosis. The correlation of mast cells and TGF-beta with the lesions of PCT has not been examined, however. The possible role of mast cells and TGF-beta (and the relationship between them) in the development of PCT lesions is discussed., Methods: To quantify mast cells and cells expressing TGF-beta in skin samples from patients with PCT and controls, immunohistochemical studies were performed in tissue sections allied to morphometric analyses., Results: The numbers of mast cells and cells expressing TGF-beta per square millimeter were increased in the PCT group relative to controls, and there was a direct and significant correlation between the mast cell number and cells expressing TGF-beta in PCT., Conclusions: The results suggest that the increased number of mast cells and of cells expressing TGF-beta, as well as their direct correlation, may contribute to the pathogenesis of the skin lesions in PCT.

Background/aims: Sporadic Porphyria Cutanea Tarda (sPCT) is associated with liver disease, e.g. HCV infection, haemochromatosis and especially alcoholic liver disease. We conducted a retrospective analysis on the prevalence of liver disorders in association with Porphyria Cutanea Tarda (PCT), in a university referral centre., Methods: The PCT cases were retrieved from computerized databases. Patient files lacking information on the presence of concomitant liver disease were excluded from further analysis., Results: 29 PCT patients were retrieved from our databases, of which 17 patients with sPCT were retained for further analysis. Patients were middle aged (mean age: 43 +/- 3) and there was no gender difference (10 males vs. 7 females). Almost all patients had iron overload (14/17). 5 patients had chronic HCV, with type 1b in 3 of them, 7 abused alcohol, 4 patients had hereditary haemochromatosis (3 homozygous C282Y--1 heterozygous H63D/C282Y). In 3 patients sPCT was associated with medication intake and one patient had chronic hepatitis B (HBV). 13 patients were treated with phlebotomies, with success in 11/13. 4 patients were treated with chloroquine, 3 of which also underwent phlebotomies. Of the 5 patients with HCV, 3 were successfully treated with combined antiviral therapy; one of them is planned to be treated; one patient never received therapy and was lost from follow-up. One patient developed hepatocellular carcinoma (HCC) during a median follow-up of 24 years., Conclusions: We found a significant association between sPCT and liver disorders, such as chronic HCV infection, alcohol abuse, iron overload and hereditary haemochromatosis. Therefore, patients presenting with PCT should be screened for concomitant liver disease. Iron overload is present in a majority of patients, the majority of patients can be successfully treated with phlebotomies. The risk of developing HCC in our sPCT patients and in literature is low.

Arsenicals are proven carcinogens in humans and it imposes significant health impacts on both humans and animals. Recently monomethylarsonous acid (MMA(III)), the toxic metabolite of arsenic has been identified in human urine and believed to be more acutely toxic than arsenite and arsenate. Arsenic also affects the activity of a number of haem biosynthesis enzymes. As a part of 2-year arsenic carcinogenicity study, young female C57BL/6J mice were given drinking water containing 0, 100, 250 and 500 microg/L arsenic as MMA(III)ad libitum. 24 h urine samples were collected at 0, 1, 2, 4, 8 weeks and every 8 weeks for up to 104 weeks. Urinary arsenic speciation and porphyrins were measured using HPLC-ICP-MS and HPLC with fluorescence detection respectively. DMA(V) was a major urinary metabolite detected. Significant dose-response relationship was observed between control and treatment groups after 1, 4, 24, 32, 48, 56, 88, 96 and 104 weeks. The level of uroporphyrin in 250 and 500 microg As/L group is significantly different from the control group after 4, 8, 16, 32, 56, 72, 80, 96 and 104 weeks. Coproporphyrin I level in 500 microAs/L group is significantly different from control group after 8, 24, 32, 40, 56, 72, 80, 88 and 104 weeks. After 4 weeks the level of coproporphyrin III concentration significantly increased in all the treatment groups compared to the control except week 16 and 48. Our results show urinary DMA(V) and porphyrin profile can be used as an early warning biomarker for chronic MMA(III) exposure before the onset of cancer.

To investigate the effects of arsenic exposure on porphyrins excretion profiles in human, porphyrins were measured by HPLC and total arsenic by HG-AAS in urine samples collected from arsenicosis-endemic areas and control sites in Guizhou Province. Analytical data showed that urinary uroporphyrin-III and coproporphyrin-III were significantly elevated in arsenic-exposed group compared with those in control group, while urinary coproporphyrin-I was not significantly higher in arsenic-exposed group than that in control group. Not any significant difference was found in porphyrins between the male and female except for 20-40 years age group. As far as age was concerned, arsenic-exposed group of <20 years showed significant increases in uroporphyrin-III and coproporphyrin-III compared with the control group of <20 years. Similarly, arsenic-exposed groups of 20-40 years and >40 years also showed significant increases in coproporphyrin-III compared with corresponding age groups of control. Besides, there were positive correlations between the urinary arsenic and total coproporphyrin, and total porphyrin. The effects of arsenic exposure were associated with increased porphyrins excretion, which was suggested that porphyrins were possible to be used as biomarkers of early health effect due to arsenicosis.

Background: Conflicting results were reported about the efficacy of vitamin E (E) treatment in porphyria cutanea tarda (PCT). We conducted a study in PCT patients to investigate whether E treatment has any additional beneficial effects compared with phlebotomy (P) treatment alone on rheological and oxidative stress parameters., Methods: Twenty three patients with sporadic PCT in clinical remission and 10 healthy control patients were studied. All patients were treated with P prior to the study until clinical remission was achieved. Baseline routine laboratory [blood glucose, serum lipids, C-reactive protein (CRP), iron metabolism indices, liver function tests], oxidative stress [serum thiobarbituric acid reactive substances (TBARS), plasma H-donor activity, plasma free SH-groups, erythrocyte glutathion peroxidase activity] and rheological parameters (whole blood and plasma viscosity, cell transit time, clogging rate) were measured in both groups. Then all PCT patients received E (tocopherol acetate) 200 mg/day for 8 weeks and at the end of treatment measurements identical to those performed at baseline were repeated., Results: Increased urine uroporphyrin, serum CRP, TBARS concentrations, whole blood and plasma viscosity and decreased plasma H-donor activity, free SH-group level, erythrocyte glutathione peroxidase activity were detected in PCT patients treated with P alone compared with control group consistent with residual oxidative stress in PCT patients. E treatment decreased urine uroporphyrin and serum TBARS concentrations; increased plasma H-donor activity and did not influence whole blood and plasma viscosity compared with P treatment alone., Conclusions: E treatment reduced the residual oxidative stress and did not influence increased plasma and whole blood viscosity present in PCT patients receiving P treatment prior to clinical remission.

To address a possible environmental contribution to autism, we carried out a retrospective study on urinary porphyrin levels, a biomarker of environmental toxicity, in 269 children with neurodevelopmental and related disorders referred to a Paris clinic (2002-2004), including 106 with autistic disorder. Urinary porphyrin levels determined by high-performance liquid chromatography were compared between diagnostic groups including internal and external control groups. Coproporphyrin levels were elevated in children with autistic disorder relative to control groups. Elevation was maintained on normalization for age or to a control heme pathway metabolite (uroporphyrin) in the same samples. The elevation was significant (P < 0.001). Porphyrin levels were unchanged in Asperger's disorder, distinguishing it from autistic disorder. The atypical molecule precoproporphyrin, a specific indicator of heavy metal toxicity, was also elevated in autistic disorder (P < 0.001) but not significantly in Asperger's. A subgroup with autistic disorder was treated with oral dimercaptosuccinic acid (DMSA) with a view to heavy metal removal. Following DMSA there was a significant (P = 0.002) drop in urinary porphyrin excretion. These data implicate environmental toxicity in childhood autistic disorder.

Forty-three patients with metabolic syndrome (MS) were examined. The urinary (uroporphyrin--UP and coproporphyrin--CP) and fecal (CP and protoporphyrin) fractions of porphyrin, as well as the urinary excretion of porphyrin precursors (S-aminolevulinic acid and porphobilinogen) were measured. Porphyrin metabolic disturbances were registered in 33 (76.7%) patients. Nine of these patients displayed such qualitative changes as fraction mismatch (CP/UP < 1; the normal value is 2.1 +/- 0.4), and an increase in the level of porphyrin precursors, while their total urinary porphyrin level was normal. In 24 patients pathological changes in porphyrin exchange were characterized by such quantitative changes as a many-fold increase in urinary and/or fecal porphyrin fraction as well as the development of secondary biochemical coproporphyrinuria syndromes, symptomatic elevation of fecal porphyrin level, and latent late cutaneous porphyria. Changes in porphyrin exchange in patients with metabolic syndrome broaden the scope of disturbances occurring in this syndrome, and allow considering these changes as additional criteria.

Background: Identification of porphyrias relies on the measurement of different porphyrins in urine, feces and plasma. Separation of porphyrin isomers is essential for the differential diagnosis of some porphyrias., Method: Separation of naturally occurring porphyrins was achieved on a Chromolith RP-18 column with fluorimetric detection using a methanol/ammonium acetate gradient mobile phase. Fecal and plasma porphyrins were extracted with acetonitrile and water at different pH values., Results: Eight porphyrins including protoporphyrin eluted within 20 min with good resolution of each of the I and III positional isomer pairs for standards, urine and plasma, and within 50 min for feces. Improvement of the extraction method for fecal and plasmatic porphyrins resulted in high recovery (up to 89%) and reliable quantification of protoporphyrin., Conclusions: The present RP-HPLC method is specific and efficient for routine analysis of porphyrins in human urine, feces and plasma.

The importance of disturbances of porphyrin metabolism in solar urticaria is discussed. 15 cases of porphyrias with sun sensitivity are presented comprising 5 cases of erythropoietic protoporhyria, 8 cases of coproporphyria hereditaria and 2 cases of porphyria variegata, 9 out of these 10 patients presented neuroabdominal symptoms and in 4 cases contraceptive pills have triggered the disease. Due to the risk of severe forms of disease sometimes drugs induced porphyrias must be considered in all cases of solar urticaria and a correct laboratory study done in the suspected cases.

We report the case of a 37-years-old woman with inappropriate antidiuretic hormone syndrome due to an attack of acute porphyria. The patient was admitted to our hospital for abdominal pain, sleepiness and pink urine. Family and personal history were normal. Seven days before the admission the patient had a laparoscopy operation for endometriosis in her left ovary. The patient had had two normal pregnancies. The physical examination was normal, the skin turgor was good and no edema was present, the blood pressure was 140/90 mmHg. Her serum sodium was 114 mEq/L, serum osmolality 243 mOsm/kg, urine sodium 146 mEq/L and urine osmolality 457 mOsm/kg. Values from laboratory examination revealed a normal peripheral haematogram, a normal kidney function, normal liver, adrenal and thyroid function. The urine tested for amino-levulinic acid, coproporphyrin and uroporphyrin was strongly positive. These findings are compatible with Porphyria Variegata or Coproporphyria Hereditary. A diagnosis of Porphyria acute with SIADH was made, and water fluid restriction, i.v. hypertonic saline infusion and furosemide to correct the hyponatremia was begun. In 1966, lesions of the median eminence of the hypothalamus and both hypothalamic -hypophyseal tracts were described in a patient with Porphyria acute intermittent and SIADH. It was suggested that SIADH occurred because of damage to these areas of the brain from excessive exposure to porphyrins.

Background: We evaluated a quality control scheme for the measurement of urinary uroporphyrin, coproporphyrin, total urinary porphyrins and precursors of urinary porphyrins, delta-aminolevulinic acid and porphobilinogen that was performed in The Netherlands during a period of 5 years., Methods: Six quality control samples were distributed each year to the participating laboratories. Mean concentrations and the corresponding coefficients of variation were calculated., Results: Coefficients of variation varied widely and were very high in the concentration ranges that can be found in patients with low-grade porphyria., Conclusion: Commutable calibrators are needed to improve the laboratory diagnosis of porphyria.

Patients with overt porphyria cutanea tarda (PCT) show a distinctive and abnormal urinary profile of porphyrin excretion. It is not known, however, whether clinical remission of the disease produces complete normalization of this profile. We selected 46 patients, previously diagnosed with PCT, who after treatment presented normal levels of total porphyrins in urine (< 35 nmol/mmol creatinine). We analyzed their urine specimens by hplc to identify and quantify the various porphyrins and we compared the urinary porphyrin profiles to those of 40 healthy volunteers. While healthy volunteers gave a pattern dominated by excretion of coproporphyrin III, 80% of the PCT patients in clinical remission showed the characteristic profile of PCT, with decreased coproporphyrin-to-uroporphyrin ratio and/or inversion of the normal coproporphyrin III-to-coproporphyrin I ratio. Detection of uroporphyrin III and heptacarboxyl III intermediates was significantly more common among the patients than the controls (p < 0.05). This study shows that PCT patients demonstrate persistent changes in urinary porphyrin profiles during clinical remission, even when total urinary porphyrin excretion has fallen to the normal range.

Two major risk factors for the development of porphyria cutanea tarda (PCT) are alcohol consumption and homozygosity for the C282Y mutation in the hereditary hemochromatosis gene (HFE). To develop an animal model, Hfe knockout mice were treated continuously with 10% ethanol in drinking water. By 4 months, uroporphyrin (URO) was detected in the urine. At 6 to 7 months, hepatic URO was increased and hepatic uroporphyrinogen decarboxylase (UROD) activity was decreased. Untreated Hfe(-/-) mice or wild-type mice treated with or without ethanol did not show any of these biochemical changes. Treatment with ethanol increased hepatic nonheme iron and hepatic 5-aminolevulinate synthase activity in Hfe(-/-) but not wild-type mice. The increases in nonheme iron in Hfe(-/-) mice were associated with diffuse increases in iron staining of parenchymal cells but without evidence of significant liver injury. In conclusion, the results of this study suggest that the uroporphyrinogenic effect of ethanol is mediated by its effects on hepatic iron metabolism. Ethanol-treated Hfe(-/-) mice seem to be an excellent model for studies of alcohol-mediated PCT.

This report describes a case of sporadic porphyria cutanea tarda involving a 38-year-old Moroccan man. Clinical diagnosis was based on characteristic features, i.e., facial hypertrichosis and bullous lesions lasting four months during the summer of 2000 followed by macular scarring on the dorsal surfaces on the hands. Three well-known precipitating factors were noted, i.e., sun, ethanol and hepatitis C virus infection. Laboratory diagnosis was based on dark red urine and elevated serum and urine uroporphyrin levels. Enhanced uroporphyrin production was due to urodecarboxylase deficiency in the liver. Urodecarboxylase activity in red blood cells and serum ferritin level were normal. The patient is heterozygous for the His63Asp HFE gene mutation associated with hereditary hemochromatosis. The photoprotective effect of melanin in this dark-skinned patient failed to offset uroporphyrin-induced photosensitivity. Avoidance of sun, ethanol and phlebotomy have prevented recurrences.

Purpose: To report a case of porphyria cutanea tarda presenting as cicatricial conjunctivitis., Design: Observational study., Methods: A 31-year-old man presented with bilateral inferior symblepharon, superior tarsal conjunctival scarring and concretions, and recurrent conjunctival and episcleral injection., Results: Four years after initial presentation, the patient developed hepatitis C, and 2 years later blisters on his scalp and hands. Direct immunofluorescence studies of biopsies taken from the palpebral conjunctiva of the right lower lid were negative for cicatricial pemphigoid. A twenty-four hour urine specimen analysis revealed elevated levels of uroporphyrins and polycarboxylated porphyrins, confirming the diagnosis of porphyria cutanea tarda. The patient was treated with repeated phlebotomies and oral hydroxychloroquine, which resulted in a significant decrease in the skin lesions, conjunctival injection, and concretions under the upper lids., Conclusions: Cicatricial conjunctivitis may be a manifestation of porphyria cutanea tarda.

Variegate porphyria (VP) is an inherited metabolic disease resulting from the partial deficiency of protoporphyrinogen oxidase, the penultimate enzyme in the heme biosynthetic pathway. We have evaluated the clinical and biochemical outcome of 103 Finnish VP patients diagnosed between 1966 and 2001. Fifty-two per cent of patients had experienced clinical symptoms: 40% had photosensitivity, 27% acute attacks and 14% both manifestations. The proportion of patients with acute attacks has decreased dramatically from 38 to 14% in patients diagnosed before and after 1980, whereas the prevalence of skin symptoms had decreased only subtly from 45 to 34%. We have studied the correlation between PPOX genotype and clinical outcome of 90 patients with the three most common Finnish mutations I12T, R152C and 338G-->C. The patients with the I12T mutation experienced no photosensitivity and acute attacks were rare (8%). Therefore, the occurrence of photosensitivity was lower in the I12T group compared to the R152C group (P=0.001), whereas no significant differences between the R152C and 338G-->C groups could be observed. Biochemical abnormalities were significantly milder suggesting a milder form of the disease in patients with the I12T mutation. In all VP patients, normal excretion of protoporphyrin in faeces in adulthood predicted freedom from both skin symptoms and acute attacks. The most valuable test predicting an increased risk of symptoms was urinary coproporphyrin, but only a substantially increased excretion exceeding 1,000 nmol/day was associated with an increased risk of both skin symptoms and acute attacks. All patients with an excretion of more than 1,000 nmol/day experienced either skin symptoms, acute attacks, or both.

Porphyria cutanea tarda (PCT) is a metabolic disorder of heme biosynthesis, characterized by reduced uroporphyrinogen decarboxylase (UROD) activity and increased urinary excretion of eight and seven carboxyl group porphyrins. Specific factors such as iron, alcohol and halogenated compounds further inhibit enzyme activity by generating reactive oxygen species. Antioxidant vitamin E has frequently been used to counteract oxidative stress in porphyria patients, but a number of studies have failed to detect any significant effect on porphyrin metabolism. Since the use of vitamin E in the treatment of porphyria is a debated question, it seemed of interest to administer high doses to five patients with PCT in order to evaluate the effects on urine porphyrin excretion. The patients had high urinary porphyrin excretion levels, but vitamin E significantly reduced the urinary excretion of eight carboxyl group porphyrins. This result is attributable to the increase in UROD activity caused by the vitamin, which is a known scavenger of the oxygen reactive species that interfere with the activity of the enzyme. In conclusion, this paper shows that vitamin E high doses significantly lowers the urine porphyrin excretion in studied patients affected by PCT., (Copyright 2002 Elsevier Science Ltd. All rights reserved.)

The effect of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on the liver of C57BL/6J mice is a model for clinical sporadic porphyria cutanea tarda (PCT). There is massive uroporphyria, inhibition of uroporphyrinogen decarboxylase (UROD) activity, and hepatocellular damage. A variety of evidence implicates the CYP1A2 enzyme as necessary for mouse uroporphyria. Here we report that, 5 weeks after a single oral dose of TCDD (75 microg/kg), Cyp1a2(+/+) wild-type mice showed severe uroporphyria and greater than 90% decreases in UROD activity; in contrast, despite exposure to this potent agent Cyp1a2(-/-) knockout mice displayed absolutely no increases in hepatic porphyrin levels, even after prior iron overload, and no detectable inhibition of UROD activity. Plasma levels of alanine-aminotransferase (ALT) and aspartate aminotransferase (AST)-although elevated in both genotypes after TCDD exposure-were significantly less in Cyp1a2(-/-) than in Cyp1a2(+/+) mice, suggesting that the absence of CYP1A2 also affords partial protection against TCDD-induced liver toxicity. Histological examination confirmed a decrease in hepatocellular damage in TCDD-treated Cyp1a2(-/-) mice; in particular, there was no bile duct damage or proliferation that in the Cyp1a2(+/+) mice might be caused by uroporphyrin. We conclude that CYP1A2 is both necessary and essential for the potent uroporphyrinogenic effects of TCDD in mice, and that CYP1A2 also plays a role in contributing to TCDD-induced hepatocellular injury. This study has implications for both the toxicity assessment of TCDD and the hepatic injury seen in PCT patients., (Copyright 2001 Academic Press.)

The aim of the study was to determine whether monobromobenzene (BB) and hexabromobenzene (HBB) administered repeatedly (for 28 days) to female rats resulted in disturbances of heme synthesis. 5-Aminolevulinate dehydratase (ALA-D) and 5-aminolevulinate synthase (ALA-S) activities were slightly changed and the concentration of glutathione increased. The excretion of 5-aminolevulinic acid (ALA-U) in urine after all doses of BB and HBB increased already in the first week. After BB administration, increased excretion of coproporphyrins was detected only at the highest dose. The increased excretion of coproporphyrins following the administration of HBB could be observed already at the lowest dose (15 mg/kg). The excretion of uroporphyrins increased after two higher doses (75 and 375 mg/kg) in the fourth week of exposure. HBB also caused elevation of microsomal P450 level. The data suggest porphyrogenic activity of HBB; whereas in the case of BB we cannot exclude that elevated excretion of ALA-U resulted from kidney impairment.

Objectives: To describe the biochemical and clinical features in hereditary coproporphyria (HCP)., Design and Method: Within the last 20 years, we investigated 53 patients (male:female = 1:2.5; age = 8-86 years) suffering from HCP. We describe the characteristic levels of urine, and fecal porphyrins and their precursors in hereditary coproporphyria and present the clinical features. Especially, we measured the coproporphyrin isomers I and III., Results and Conclusion: The group of hereditary coproporphyria patients exhibited a significantly higher (p<0.0001) excretion of urinary porphyrin precursors, delta-aminolevulinic acid (median = 84 micromol/24 h) and porphobilinogen (median = 39 micromol/24 h), as compared to controls (delta-aminolevulinic acid: 22 micromol/24 h, porphobilinogen: 3 micromol/24 h; median, n = 20). The median of coproporphyrin in urine (1315 nmol/24 h) and feces (1855 nmol/g) were enhanced 12- and 168-fold, as compared to healthy subjects (urinary coproporphyrin: 106 nmol/24 h, fecal coproporphyrin: 11 nmol/g; median, n = 20). During therapy on one female patient, with IV application of heme arginate, a considerable decline of porphyrin precursors and porphyrin excretion was observed. The examination of urinary and fecal coproporphyrin isomers I and III revealed an excessive elevation of the coproporphyrin isomer III of 87% in urine and 94% in feces, respectively (normal: urinary isomer III = 69-83% and fecal isomer III = 25-40%). In feces the increase of isomer III caused an inversion of the physiologic coproporphyrin isomer III:I ratio that could be recognized in all various stages in hereditary coproporphyria and in children. Acute attacks of hereditary coproporphyria are accompanied by an acute polysymptomatic clinical syndrome, and this is associated with high levels of urinary porphyrin precursors. On review of our patients, the highest percentage had abdominal pain (89%), followed by neurologic (33%), psychiatric (28%), cardiovascular (25%), and skin symptoms (14%).

Porphyrias are a group of rare metabolic disorders in which excessive quantities of porphyrins, or their precursors, are produced. They are due to specific enzyme deficiencies resulting in abnormalities in the control of the porphyrin-haem metabolic pathway. Porphyria cutanea tarda (PCT) is the most common of all the porphyrias. However this condition is rarely seen in our Asian countries. We describe a patient with PCT who presented clinically with blistering eruptions over the sun-exposed areas. Coral pink fluorescence of uroporphyrins in an acidified urine specimen is diagnostic. Definitive treatment involves the use of low-dose chloroquine and interval venesection.

A strong association between hepatitis C virus (HCV) infection and porphyria cutanea tarda (PCT) has been observed, but the implications of the viral infection in the metabolism of porphyrins in patients without clinical manifestations of PCT are not known. The levels of porphyrin in plasma and uroporphyrin (URO) and coproporphyrin (COPRO) in 24-hour urine were measured in 156 patients with chronic HCV infection showing no clinical evidence of PCT. Levels of URO higher than the upper limit were observed in 35 of 156 patients (22.4%). The range and the mean values +/- standard deviation were 26-1,196 microg/24 hours and 82 +/- 204 microg/24 hours. Increased levels of COPRO and plasma porphyrin were observed in 12 of 156 patients (7.7%) and 2 of 156 patients (1.3%) respectively. There were no differences between patients with increased URO levels and patients with normal URO levels in terms of gender, age, risk factors for HCV infection, alcohol abuse, or hepatitis B viral infection. Transferrin saturation (p = 0.040), gamma glutamyl transpeptidase (p < 0.0001), aspartate aminotransferase (p = 0.006), and alanine aminotransferase (p = 0.040) were significantly higher in patients with abnormal URO than in patients with normal URO. The frequency of cirrhosis was higher, but not significantly different, in patients with increased URO (16.7%) compared with patients with normal URO (3.8%). The authors demonstrated that even without a clinical manifestation of PCT it is possible to detect abnormalities in the metabolism of porphyrins in patients with chronic HCV infection. The implications of these findings deserve additional investigation.

Previous work has implicated CYP1A2 in experimental uroporphyria caused by polyhalogenated aromatic compounds, and in uroporphyria caused by iron and 5-aminolevulinate (ALA) in the absence of inducers of CYP1A2. Here we examined whether the different susceptibilities of SWR and C57BL/6 strains of mice to uroporphyria in the absence of inducers of CYP1A2 are related to different levels of CYP1A2. Enzymological assays (ethoxy- and methoxyresorufin dealkylases, and uroporphyrinogen oxidation) and immunoblots indicated that there was about twice the amount of hepatic CYP1A2 in SWR mice compared with C57BL/6 mice. Immunohistochemistry revealed that CYP1A2 was located centrilobularly in the liver, and the staining was more intense in SWR mice than in C57BL/6 mice. Hepatic non-heme iron was about double in SWR compared with C57BL/6 mice. In SWR mice given iron dextran, hepatic iron was 1.7-fold that of C57BL/6 mice given iron dextran. SWR mice administered ALA in the drinking water accumulated much less hepatic protoporphyrin than did C57BL/6 mice. To confirm the importance of small increases in CYP1A2, C57BL/6 mice were given a low dose of 3-methylcholanthrene (MC) (15 mg/kg), as well as iron and ALA. There was about a 5- to 6-fold increase in hepatic uroporphyrin accumulation after 32 days on ALA compared with animals not given MC. In these animals, CYP1A2 was increased by 10-fold at 2 days, but returned to basal levels by 14 days. We conclude that small and transient differences in CYP1A2 may be important in the development of uroporphyria.

The objective of this study was to establish normal reference ranges for porphyrins in healthy neonates. There is little information about urinary porphyrin excretion in this age group. This knowledge may provide an early diagnostic tool for detecting subtle alterations or latent forms in disorders of heme biosynthesis. Fifty healthy neonates were selected from the Department of Obstetrics. Total urinary porphyrins in random specimens were analysed by a spectrofluorometry method. The measurement of porphyrin fractions was made by fluorometric high-performance liquid chromatography (HPLC). The results were adjusted to urinary creatinine excretion to correct any imprecision and interindividual variation in body mass. The urinary total porphyrin had a median value of 331.50 (nmol/L). A statistically significant relationship between total porphyrin (nmol/L) and creatinine (mmol/L) was found (p < 0.01). The porphyrin/creatinine ratio showed a median value of 56.30 nmol/mmol creatinine. The study of individual porphyrins revealed that coproporphyrin and uroporphyrin were the major porphyrins excreted in neonates (coproporphyrin represents 81.98% and uroporphyrin 16.64% of total porphyrin); in both cases, isomer I was predominant with median values of 22.36 and 6.25 nmol/mmol creatinine, respectively. No significant relationships were found between porphyrin excretion and sex, gestational age, weight, or height. Our data provide the reference limits for porphyrins in neonates as a diagnostic guideline for evaluation of subtle alterations in heme biosynthesis.

We describe a 4-year-old girl with a spontaneous blistering disorder that was consistent with porphyria cutanea tarda (PCT). There was no familial history of the disease or any obvious causative factors present. Oral hydroxychloroquine (3 mg/kg) was given twice weekly along with vitamin E (200 U/d) as an antioxidant. Within 6 weeks, marked decreased blistering occurred and by 12 weeks no blistering was evident. Despite clinical improvement and tolerance of hydroxychloroquine, urinary uroporphyrin, aspartate aminotransferase, and ferritin levels continued to rise reaching peak levels at 16 weeks of therapy. Near total biochemical remission was observed at 40 weeks and all therapy was discontinued at 60 weeks.

In the present study we have investigated the putative requirement for the cytochrome P-450 isoform CYP1A2 in murine uroporphyria, by comparing Cyp1a2(-/-) knockout mice with Cyp1a2(+/+) wild-type mice. Uroporphyria was produced by injecting animals with iron-dextran and giving the porphyrin precursor 5-aminolaevulinic acid in the drinking water. Some animals also received 3-methylcholanthrene (MC) to induce hepatic CYP1A2. In both protocols, uroporphyria was elicited by these treatments in the Cyp1a2(+/+) wild-type mice, but not in the null mutant mice. Uroporphyrinogen oxidation activity in hepatic microsomes from untreated Cyp1a2(+/+) mice was 2.5-fold higher than in Cyp1a2(-/-) mice. Treatment with MC increased hepatic CYP1A1 in both mouse lines and hepatic CYP1A2 only in the Cyp1a2(+/+) line, as determined by Western immunoblotting. MC increased hepatic ethoxy- and methoxy-resorufin O-dealkylase activities in both mouse lines, but increased uroporphyrinogen oxidation activity in the Cyp1a2(+/+) wild-type mice only. These results indicate the absolute requirement for hepatic CYP1A2 in causing experimental uroporphyria under the conditions used.

Two cases of familial porphyria cutanea tarda (PCT) with constrictive pericarditis are described. A 50-year-old woman and her 48-year-old younger brother were admitted because of right ventricular heart failure. Constrictive pericarditis was diagnosed by RV pressure waveform and echocardiogram. The patients were diagnosed as PCT based on clinical symptoms, histologic findings and elevated urinary excretion levels of uroporphyrin. Even to this day, over 40% of the etiology of constrictive pericarditis remains unknown. There is a possibility of overlooking porphyria cutanea tarda in constrictive pericarditis patients. This report describes the first documented cases of familial PCT with constrictive pericarditis.

Hexachlorobenzene (HCB)-induced porphyria occurs in female, but not male, rats after a delay of 35 days following HCB treatment. Uroporphyrinogen decarboxylase (UROD) inhibition has been proposed as a primary causative event. To determine whether there also exists a delay phase and a sexual dimorphism for UROD inhibition, groups of male and female rats were given HCB (100 mg/kg/day) from Days 1 to 5. Hepatic uroporphyrin III was markedly increased only after Day 33. Liver cytosol UROD activity in HCB-treated female rats with porphyria at Days 33, 40, 47, 54, and 100 was decreased by over 70% compared to concurrent control, whereas treated male rats as well as nonporphyric female rats had UROD activity comparable to control levels at Days 6, 12, 19, 26, 33, 40, 47, and 54. Level of immunoreactive UROD in cytosol of porphyric rats was not modified by HCB. No gender-related differences in liver cytosol radiolabel level ([14C]HCB given as the fifth dose) were found at Days 6 and 30. Chromatography of liver cytosol showed nonspecific binding of radiolabel to proteins for males, porphyric and nonporphyric females, and loss of UROD activity did not correlate with the amount of radiolabel in the UROD-containing fractions. Thus, the gender-specific decrease in UROD activity observed when porphyria develops in female rats (delay of about 4 weeks), as well as the persistence of low activity and porphyria for months, suggests that UROD inhibition was causally related to porphyria.

Hexachlorobenzene (HCB) is porphyrinogenic in adult female but not in male rats. This study aimed to assess the role of 17beta-estradiol in the induction of porphyria by HCB in both sexes by adding or removing the hormone. Groups of intact females, ovariectomized females (Ova), castrated males (Cas), and Cas receiving 17beta-estradiol (4 mg/kg, i.m., once a week beginning 2 weeks prior to HCB) were given five consecutive daily doses of HCB (100 mg/kg in corn oil, p.o.). Porphyria was assessed by urinary uroporphyrin excretion measured at days 16, 31, 38, 45, 52, 59, and 87. The percentage of porphyric rats in intact females increased from day 31 (58%) to day 87 (75%), whereas none of the Ova or Cas rats responded. However, administration of estradiol (days 120-169) and another sequence of HCB doses (days 134-138) to the same Ova rats caused porphyria (50% at day 186). Cas rats given estradiol also developed porphyria (43 and 86% on days 31 and 87, respectively). HCB-treated Ova rats given two doses of estradiol at either days 1 and 8 or days 22 and 29 developed a porphyria of similar magnitude (day 52). The role of estradiol cannot be explained by a reduction of pentachlorothiophenol formation, a putative detoxication pathway. Overall, results show that both sexes have the ability to respond to HCB when 17beta-estradiol is present and suggest that the sexual dimorphism in HCB-induced porphyria in the rat is related to the hormonal status.

We evaluated the efficacy of interferon in the treatment of a 61 year-old male patient with porphyria cutanea tarda associated with hepatitis C virus infection. After initiation of intravenous administration of interferon-beta, urinary excretion of uroporphyrin and coproporphyrin, serum transaminase, gamma-glutamyl transpeptidase levels and ferritin were gradually increased. However, after completion of interferon-beta administration for 6 weeks, urinary excretion of uroporphyrin and coproporphyrin, serum enzymes and ferritin were significantly decreased correspondent with diminished hepatitis C virus RNA titer. These results suggest that interferon may be beneficial for the treatment of porphyria cutanea tarda due to hepatitis C virus infection.

Objectives: Porphyria cutanea tarda has been reported in about 60 patients with human immunodeficiency virus (HIV) since 1987. We looked for porphyrin metabolism disorders in HIV infected patients without patent porphyria cutanea tarda., Methods: Urinary porphyrin excretion was measured in 64 patients with an HIV infection., Results: Excreted levels were abnormal in 23 patients (36%) including 4 (6%) with patterns highly suggestive of porphyria cutanea tarda. One of these patients developed the disease 2 years later. In 15 patients (23%) there was a significant increase in coproporphyrinuria. Minimal alterations in uroporphyrin or its precursors were seen in the other patients. Abnormal excretion was significantly more frequent in patients with hepatopathy and in patients who had progressed to AIDS., Conclusion: Our findings suggest that HIV infection does not play a direct role in altered porphyrin metabolism because of the frequency of liver disorders observed in these patients.

Urine porphyrin analysis is an important part in evaluation of photosensitivity. Since porphyrin excretion is variable throughout the day, analysis is traditionally based on 24-hour collections. To facilitate the use of random specimens, as well as poorly collected 24-hour specimens, reference limits based on the porphyrin to creatinine ratio have been developed. Based on 1,171 adult specimens, it is estimated that the 95 percent reference limit (90 percent confidence interval) is < or = 3.9 (3.5-5.7) mumol/mol of creatinine for uroporphyrin and < or = 22 (19-34) mumol/mol for coproporphyrin. These values apply to both 24-hour and random specimens, although random specimens show a higher degree of variability. Modest differences exist between males and females, but they are not significant given the degree of uncertainty in the confidence intervals. In terms of more traditional 24-hour units, reference limits correspond to < or = 37 (32-63) nmol/day for uroporphyrin and < or = 221 (195-320) nmol/day for coproporphyrin.

Porphyria cutanea tarda (PCT) is believed to be associated with reduced hepatic uroporphyrinogen decarboxylase activity and risk factors such as alcohol abuse and medication with oral contraceptives and certain other drugs. Recently it has been suggested that hepatitis C virus (HCV) infection may also be associated with PCT. We have therefore reviewed the prevalence of HCV infection in a series of patients with PCT in the Lothian region of Scotland. We identified 12 patients with PCT, all of whom had abnormal liver function tests. Liver histology revealed chronic active hepatitis in six patients, micronodular cirrhosis in four patients, hepatocellular carcinoma in one patient and normal findings in one HIV positive patient. Out of 12 patients tested, 11 were positive for anti-HCV antibodies by second generation enzyme linked immunosorbent assay (ELISA 2), and by recombinant immunoblot assay (RIBA 2); positive serology was confirmed by polymerase chain reaction (PCR). In a second group of 14 patients with chronic HCV infection matched for age and sex with the PCT patients, all had normal urinary uroporphyrin excretion. We have thus confirmed in Scotland early reports from Spain and Italy that PCT is strongly associated with HCV infection. This could explain the development of inflammatory changes in the liver and progression of liver disease in patients with PCT. Porphyrin metabolism, however, appears normal in patients with chronic HCV infection without PCT.

Porphyria cutanea tarda (PCT) is a clinical manifestation of decreased uroporphyrinogen decarboxylase (UPD) activity. Multiple endogenous and exogenous factors have been implicated in inducing PCT in genetically predisposed patients. The most recent is the RNA virus hepatitis C (HCV), which is transmitted via blood exposure. The mechanism of action in HCV-induced PCT is unknown but produces the same clinical, laboratory, and histopathologic changes seen in other forms of sporadic PCT. Therefore, patients presenting with PCT clinically should be tested serologically for antibodies against HCV and patients with HCV should be monitored for signs and symptoms of PCT.