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Martelli A.,Institute Of Genetique Et Of Biologie Moleculaire Et Cellulaire Igbmc | Martelli A.,French Institute of Health and Medical Research | Martelli A.,French National Center for Scientific Research | Martelli A.,University of Strasbourg | And 23 more authors.
Cell Metabolism | Year: 2015

Summary Mitochondrial iron accumulation is a hallmark of diseases associated with impaired iron-sulfur cluster (Fe-S) biogenesis, such as Friedreich ataxia linked to frataxin (FXN) deficiency. The pathophysiological relevance of the mitochondrial iron loading and the underlying mechanisms are unknown. Using a mouse model of hepatic FXN deficiency in combination with mice deficient for iron regulatory protein 1 (IRP1), a key regulator of cellular iron metabolism, we show that IRP1 activation in conditions of Fe-S deficiency increases the available cytosolic labile iron pool. Surprisingly, our data indicate that IRP1 activation sustains mitochondrial iron supply and function rather than driving detrimental iron overload. Mitochondrial iron accumulation is shown to depend on mitochondrial dysfunction and heme-dependent upregulation of the mitochondrial iron importer mitoferrin-2. Our results uncover an unexpected protective role of IRP1 in pathological conditions associated with altered Fe-S metabolism. © 2015 Elsevier Inc.

Elder G.,University of Wales | Harper P.,University of Stockholm | Badminton M.,University of Wales | Sandberg S.,University of Bergen | Deybach J.-C.,Center Francais des Porphyries
Journal of Inherited Metabolic Disease | Year: 2013

Retrospective estimates of the prevalence of porphyrias have been reported but there has been no large scale prospective study of their incidence. The European Porphyria Network collected information prospectively over a 3 year period about the number of newly diagnosed symptomatic patients with an inherited porphyria (335 patients from 11 countries). Prevalence was calculated from the incidence and mean disease duration. The incidence of hepato-cellular carcinoma (HCC) in acute hepatic porphyria and the prevalence of patients with recurrent acute attacks of porphyria were also investigated. The incidence of symptomatic acute intermittent porphyria (AIP) was similar in all countries (0.13 per million per year; 95 % CI: 0.10 - 0.14) except Sweden (0.51; 95 % CI: 0.28-0.86). The incidence ratio for symptomatic AIP: variegate porphyria: hereditary coproporphyria was 1.00:0.62: 0.15. The prevalence of AIP (5.4 per million; 95 % CI: 4.5-6.3) was about half that previously reported. The prevalence of erythropoietic protoporphyria (EPP) was less uniform between countries and, in some countries, exceeded previous estimates. Fourteen new cases of HCC (11 from Sweden) were reported in patients with acute porphyria. Sixty seven patients (3 VP; 64 AIP: 53 females, 11 males) with recurrent attacks of acute porphyria were identified. The estimated percentage of patients with AIP that will develop recurrent acute attacks was 3-5 %. In conclusion, the prevalence of symptomatic acute porphyria may be decreasing, possibly due to improved management, whereas the prevalence of EPP may be increasing due to improved diagnosis and its greater recognition as a cause of photosensitivity. © 2012 SSIEM and Springer Science+Business Media Dordrecht.

Guyon L.,Lille University Hospital Center | Farine M.-O.,Lille University Hospital Center | Lesage J.C.,University of Lille Nord de France | Gevaert A.-M.,Lille University Hospital Center | And 4 more authors.
Photodiagnosis and photodynamic therapy | Year: 2014

CONTEXT: While photodynamic therapy (PDT) is a promising treatment for peritoneal carcinomatosis, its use is often limited because of the toxicity of photosensitizers. In this study, safety of PDT with hexaminoevulinate (HAL), a second generation photosensitizer, is assessed.METHODS: PDT of the peritoneal cavity was performed in a rat model of peritoneal carcinomatosis. Rats were treated according to different protocols: with full or half HAL dose, after intraperitoneal or oral administration of HAL, 4 or 8h after its injection, using red or green light, after protection of the liver or cooling of the abdominal wall. Toxicity was assessed by blood tests quantifying hematocrit, liver and muscular enzymes and by pathological examination of abdominal and intrathoracic organs after treatment. The results were analyzed in the light of quantification of fluorescence and protoporphyrin IX (PPIX) content of the same organs.RESULTS: PDT with HAL induced rhabdomyolysis, intestinal necrosis and liver function test anomalies, leading to death in 2 out of 34 rats. The liver and the intestine contained high levels of PPIX (3-5 times more than tumor nodules).CONCLUSION: HAL PDT lacked specificity. However, the strategy associating diagnosis, treatment and evaluation of the results in one single procedure was effective and should be tested with other photosensitizers. Copyright © 2014 Elsevier B.V. All rights reserved.

Katugampola R.P.,University of Cardiff | Anstey A.V.,University of Cardiff | Finlay A.Y.,University of Cardiff | Whatley S.,University of Wales | And 12 more authors.
British Journal of Dermatology | Year: 2012

Background Congenital erythropoietic porphyria (CEP) is an autosomal recessive photomutilating porphyria with onset usually in childhood, where haematological complications determine prognosis. Due to its extreme rarity and clinical heterogeneity, management decisions in CEP are often difficult. Objectives To develop a management algorithm for patients with CEP based on data from carefully characterized historical cases. Methods A single investigator collated data related to treatments and their outcomes in 29 patients with CEP from the U.K., France, Germany and Switzerland. Results Six children were treated with bone marrow transplantation (BMT); five have remained symptomatically cured up to 11·5 years post-transplantation. Treatments such as oral charcoal, splenectomy and chronic hypertransfusion were either of no benefit or were associated with complications and negative impact on health-related quality of life. Lack of consistent genotype-phenotype correlation meant that this could not be used to predict disease prognosis. The main poor prognostic factors were early age of disease onset and severity of haematological manifestations. Conclusions A management algorithm is proposed where every patient, irrespective of disease severity at presentation, should receive a comprehensive, multidisciplinary clinical assessment and should then be reviewed at intervals based on their predicted prognosis, and the rate of onset of complications. A BMT should be considered in those with progressive, symptomatic haemolytic anaemia and/or thrombocytopenia. Uroporphyrinogen III synthase genotypes associated with poor prognosis would additionally justify consideration for a BMT. Rigorous photoprotection of the skin and eyes from visible light is essential in all patients. See also the Commentary by Sarkany © 2012 British Association of Dermatologists.

Gelot P.,Nantes University Hospital Center | Dutartre H.,Nantes University Hospital Center | Khammari A.,Nantes University Hospital Center | Khammari A.,French Institute of Health and Medical Research | And 9 more authors.
Experimental Dermatology | Year: 2013

Vemurafenib is a new-targeted therapy approved for the treatment of patients with V600E BRAF-mutant metastatic melanoma. Among the cutaneous adverse events reported, the photosensitivity is frequently experienced. We aimed to characterize more deeply the mechanism leading to this photosensitivity as well as the corresponding UV spectrum. Phototests showed that the phototoxicity was UVA-dependent since from normal value prior to vemurafenib treatment, the UVA-minimal erythema dose decreased in 17 of 18 patients (94.4%) while the minimal erythema dose remained unchanged. Furthermore, a vemurafenib-induced erythema appeared quickly during the UVA exposure contrarily to what is observed with a conventional drug-induced phototoxicity showing an erythema 12-24 h after the phototesting. Vitamin PP concentration decreased, and porphyrin level significantly increased after 2 months of vemurafenib. Our study confirms the high risk of vemurafenib-induced photosensitivity and indicates that it is possibly vitamin PP- and porphyrin dependent. © 2013 John Wiley & Sons A/S.

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