Publications by authors named "Jean Charles Deybach"

Article Synopsis
  • Porphyrias are rare inherited disorders caused by enzyme activity changes in haem synthesis, leading to the buildup of harmful intermediates that cause skin and nerve issues due to their photoreactive and neurotoxic properties.
  • Current treatments are not very effective, and there's limited understanding of how they work, prompting research into new therapies that target the root causes of the disease through gene therapy and molecular techniques.
  • Advances in nanotechnology are improving drug delivery systems, allowing for better treatment options and the potential for repurposing existing medications to help manage porphyrias effectively.
View Article and Find Full Text PDF
Article Synopsis
  • - The text summarizes the historical progression of understanding porphyrias, a group of disorders linked to haem biosynthesis, starting from the first cases reported in the 19th century to significant contributions by scientists like Meyer-Betz, Günther, and Waldenström.
  • - Major breakthroughs include the classification and identification of different types of porphyrias, the discovery of porphobilinogen’s role in acute porphyria, and Hans Fischer's Nobel-winning work on porphyrin structure and haemin synthesis in the early 20th century.
  • - By 2000, advancements in genetic research allowed for the cloning and sequencing of haem biosynthesis genes, leading to improved understanding of inherited porphyrias and the development of
View Article and Find Full Text PDF

Objectives: To assess the performance of 405 nm-induced autofluorescence for the characterization of primary liver nodules on ex vivo resected specimens.

Materials And Methods: Forty resected liver specimens bearing 53 primary liver nodules were included in this IRB-approved prospective study. Intratissular spectroscopic measurements were performed using a 25-G fibered-needle on all ex vivo specimens: 5 autofluorescence measurements were performed in both nodules and adjacent parenchyma.

View Article and Find Full Text PDF

Background And Aims: Acute hepatic porphyria comprises a group of rare genetic diseases caused by mutations in genes involved in heme biosynthesis. Patients can experience acute neurovisceral attacks, debilitating chronic symptoms, and long-term complications. There is a lack of multinational, prospective data characterizing the disease and current treatment practices in severely affected patients.

View Article and Find Full Text PDF
Article Synopsis
  • Porphyrias are rare genetic disorders that happen when certain enzymes in the body don't work right, causing harmful substances to build up.
  • These build-ups can lead to skin problems when exposed to sunlight and can also cause severe stomach and nerve pain.
  • Researchers are learning more about how these disorders happen, which could help create better treatments that target the root of the problem instead of just the symptoms.
View Article and Find Full Text PDF

With the advent of precision and genomic medicine, a critical issue is whether a disease gene variant is pathogenic or benign. Such is the case for the three autosomal dominant acute hepatic porphyrias (AHPs), including acute intermittent porphyria, hereditary coproporphyria, and variegate porphyria, each resulting from the half-normal enzymatic activities of hydroxymethylbilane synthase, coproporphyrinogen oxidase, and protoporphyrinogen oxidase, respectively. To date, there is no public database that documents the likely pathogenicity of variants causing the porphyrias, and more specifically, the AHPs with biochemically and clinically verified information.

View Article and Find Full Text PDF

Erythropoietic protoporphyria (EPP) is a hereditary disease characterized by a deficiency in ferrochelatase (FECH) activity. FECH activity is responsible for the accumulation of protoporphyrin IX (PPIX). Without etiopathogenic treatment, EPP manifests as severe photosensitivity.

View Article and Find Full Text PDF
Article Synopsis
  • Scientists are exploring how mRNA can be used to make proteins that help treat many diseases.
  • A study showed that giving mRNA for a specific protein (PBGD) through an IV can help fix a problem in the liver.
  • This method was found to be safe and effective in models used before testing on humans for a disease called acute intermittent porphyria.
View Article and Find Full Text PDF
Article Synopsis
  • Porphyrias are genetic disorders that disrupt the heme biosynthesis pathway and include acute intermittent porphyria, variegate porphyria, and hereditary coproporphyria, which are linked to an increased risk of liver cancers, particularly hepatocellular carcinoma (HCC).
  • The incidence of HCC in patients with acute hepatic porphyrias ranges from 0.16% to 0.35%, with higher rates observed in older populations living in Sweden and Norway due to genetic factors.
  • The study explores the potential causes of HCC in these patients, emphasizes the need for regular imaging screenings for those over 50, and discusses the utility of a new non-invasive marker, PIVKA-II, for monitoring liver
View Article and Find Full Text PDF

Acute intermittent porphyria (AIP) is a disease affecting the heme biosynthesis pathway caused by mutations of the hydroxymethylbilane synthase (HMBS) gene. AIP is thought to display autosomal dominant inheritance with incomplete penetrance. We evaluated the prevalence, penetrance and heritability of AIP, in families with the disease from the French reference center for porphyria (CFP) (602 overt patients; 1968 relatives) and the general population, using Exome Variant Server (EVS; 12 990 alleles) data.

View Article and Find Full Text PDF

Hemolysis occurring in hematologic diseases is often associated with an iron loading anemia. This iron overload is the result of a massive outflow of hemoglobin into the bloodstream, but the mechanism of hemoglobin handling has not been fully elucidated. Here, in a congenital erythropoietic porphyria mouse model, we evaluate the impact of hemolysis and regenerative anemia on hepcidin synthesis and iron metabolism.

View Article and Find Full Text PDF
Article Synopsis
  • Regulation of 5-aminolevulinate synthase (ALAS) is crucial for maintaining balanced heme production, with mutations in the hALAS2 enzyme linked to X-linked protoporphyria (XLPP), a disease causing severe sensitivity to light.
  • Research on mutant variants of hALAS2 showed that these XLPP mutations increase the enzyme's activity by speeding up the release of the product 5-aminolevulinate (ALA) from the enzyme.
  • The study suggests that the XLPP mutations destabilize the enzyme's structure, disrupting normal regulation and leading to the accumulation of porphyrins in the bloodstream.
View Article and Find Full Text PDF

The hereditary porphyrias comprise a group of eight metabolic disorders of the heme biosynthesis pathway. Each porphyria is caused by abnormal function at a separate enzymatic step resulting in a specific accumulation of heme precursors. Porphyrias are classified as hepatic or erythropoietic, based on the organ system in which heme precursors (δ-aminolevulinic acid [ALA], porphobilinogen and porphyrins) are overproduced.

View Article and Find Full Text PDF
Article Synopsis
  • Erythropoietic protoporphyria is a painful skin condition that leads to severe discomfort from sunlight exposure, prompting researchers to test afamelanotide, an α-melanocyte-stimulating hormone analogue, for relief.
  • In two randomized trials involving a total of 168 patients from the U.S. and Europe, participants received either afamelanotide or a placebo implant every 60 days, with assessments on pain, phototoxic reactions, and quality of life.
  • Results showed that those receiving afamelanotide experienced significantly longer pain-free exposure to sunlight and reported improved quality of life without serious side effects attributed to the drug.
View Article and Find Full Text PDF
Article Synopsis
  • Acute intermittent porphyria (AIP) is a genetic disorder caused by a deficiency of the enzyme hydroxymethylbilane synthase (HMBS), affecting heme production and primarily impacting the nervous system.
  • Research on Hmbs(-/-) mice revealed alterations in mitochondrial oxidative phosphorylation (OXPHOS), showing an initial adaptive response to HMBS deficiency, followed by significant changes due to phenobarbital treatment.
  • Treatment with heme arginate (HA) mitigated the reduction in ATP production in skeletal muscle, indicating that both neurotoxicity from certain compounds and mitochondrial dysfunction are vital in understanding AIP's effects.
View Article and Find Full Text PDF
Article Synopsis
  • Acute intermittent porphyria (AIP) is a genetic condition caused by a deficiency in a key enzyme, leading to the overproduction of harmful substances that can affect the kidneys.
  • A study involving 415 AIP patients revealed that 59% suffered from chronic kidney disease, with typical signs including a gradual decline in kidney function and specific renal pathologies, despite the absence of protein in urine.
  • Experimental findings showed that the porphyrin precursors from AIP can cause stress and damage in kidney cells, suggesting that AIP-related kidney disease warrants diagnosis in patients with certain types of kidney damage.
View Article and Find Full Text PDF

Many red cell polymorphisms are a result of selective pressure by the malarial parasite. Here, we add another red cell disease to the panoply of erythrocytic changes that give rise to resistance to malaria. Erythrocytes from individuals with erythropoietic protoporphyria (EPP) have low levels of the final enzyme in the heme biosynthetic pathway, ferrochelatase.

View Article and Find Full Text PDF

Hereditary porphyrias comprise a group of eight metabolic disorders of the haem biosynthesis pathway, characterised by acute neurovisceral symptoms and/or skin lesions. Each porphyria is caused by abnormal functioning of a particular enzymatic step, resulting in specific accumulation of heme precursors. Seven porphyrias are due to a partial enzyme deficiency, while a gain-of-function mechanism has recently been identify in a novel porphyria.

View Article and Find Full Text PDF
Article Synopsis
  • Acute intermittent porphyria (AIP) is a genetic liver disorder caused by a deficiency in the HMBS enzyme, leading to dangerous attacks due to high production of 5-aminolaevulinic acid (ALA).
  • A study using Hmbs knockout mice treated with phenobarbital showed significant impairments in mitochondrial respiratory chain and TCA cycle activities.
  • Treatment with heme arginate after phenobarbital helped restore some metabolic function, highlighting potential therapeutic strategies to mitigate the effects of AIP on mitochondrial energy metabolism.
View Article and Find Full Text PDF

In 90% of people with erythropoietic protoporphyria (EPP), the disease results from the inheritance of a common hypomorphic FECH allele, encoding ferrochelatase, in trans to a private deleterious FECH mutation. The activity of the resulting FECH enzyme falls below the critical threshold of 35%, leading to the accumulation of free protoporphyrin IX (PPIX) in bone marrow erythroblasts and in red cells. The mechanism of low expression involves a biallelic polymorphism (c.

View Article and Find Full Text PDF

(1)H NMR is a nonbiased technique for the quantification of small molecules that could result in the identification and characterization of potential biomarkers with prognostic value and contribute to better understand pathophysiology of diseases. In this study, we used (1)H NMR spectroscopy to analyze the urinary metabolome of patients with acute intermittent porphyria (AIP), an inherited metabolic disorder of heme biosynthesis in which an accumulation of the heme precursors 5-aminolaevulinic acid (ALA) and porphobilinogen (PBG) promotes sudden neurovisceral attacks, which can be life-threatening. Our objectives were (1) to demonstrate the usefulness of (1)H NMR to identify and quantify ALA and PBG in urines from AIP patients and (2) to identify metabolites that would predict the response to AIP crisis treatment and reflect differential metabolic reprogramming.

View Article and Find Full Text PDF

Disorders of iron metabolism are among the most common acquired and constitutive diseases. Hemochromatosis has a solid genetic basis and in Northern European populations it is usually associated with homozygosity for the C282Y mutation in the HFE protein. However, the penetrance of this mutation is incomplete and the clinical presentation is highly variable.

View Article and Find Full Text PDF

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.

View Article and Find Full Text PDF