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Medicine Apr 2024X-linked adrenoleukodystrophy (X-ALD) is caused by mutations in the ABCD1 gene leading to very long chain fatty acid (VLCFA) accumulation. The disease demonstrates a...
RATIONALE
X-linked adrenoleukodystrophy (X-ALD) is caused by mutations in the ABCD1 gene leading to very long chain fatty acid (VLCFA) accumulation. The disease demonstrates a spectrum of phenotypes including adrenomyeloneuropathy (AMN). We aimed to identify the genetic basis of disease in a patient presenting with AMN features in order to confirm the diagnosis, expand genetic knowledge of ABCD1 mutations, and elucidate potential genotype-phenotype associations to inform management.
PATIENT CONCERNS
A 29-year-old male presented with a 4-year history of progressive spastic paraplegia, weakness of lower limbs, fecal incontinence, sexual dysfunction, hyperreflexia, and positive Babinski and Chaddock signs.
DIAGNOSES
Neuroimaging revealed brain white matter changes and spinal cord thinning. Significantly elevated levels of hexacosanoic acid (C26:0) and tetracosanoic acid (C24:0) suggested very long chain fatty acids (VLCFA) metabolism disruption. Genetic testing identified a novel hemizygous ABCD1 mutation c.249dupC (p.F83fs). These findings confirmed a diagnosis of X-linked ALD with an AMN phenotype.
INTERVENTIONS
The patient received dietary counseling to limit VLCFA intake. Monitoring for adrenal insufficiency and consideration of Lorenzo's oil were advised. Genetic counseling and testing were offered to at-risk relatives.
OUTCOMES
At present, the patient continues to experience progressive paraplegia. Adrenal function remains normal thus far without steroid replacement. Family members have undergone predictive testing.
LESSONS
This case expands the known mutation spectrum of ABCD1-linked X-ALD, providing insight into potential genotype-phenotype correlations. A thoughtful diagnostic approach integrating clinical, biochemical and genetic data facilitated diagnosis. Findings enabled genetic counseling for at-risk relatives regarding this X-linked disorder.
Topics: Adult; Humans; Male; Adrenal Insufficiency; Adrenoleukodystrophy; ATP Binding Cassette Transporter, Subfamily D, Member 1; Fatty Acids, Nonesterified; Mutation; Paraplegia; Phenotype
PubMed: 38640304
DOI: 10.1097/MD.0000000000037874 -
Biochimica Et Biophysica Acta.... Jun 2024Mevalonate kinase deficiency (MKD) is an autosomal recessive metabolic disorder associated with recurrent autoinflammatory episodes. The disorder is caused by bi-allelic...
Mevalonate kinase deficiency (MKD) is an autosomal recessive metabolic disorder associated with recurrent autoinflammatory episodes. The disorder is caused by bi-allelic loss-of-function variants in the MVK gene, which encodes mevalonate kinase (MK), an early enzyme in the isoprenoid biosynthesis pathway. To identify molecular and cellular consequences of MKD, we studied primary fibroblasts from severely affected patients with mevalonic aciduria (MKD-MA) and more mildly affected patients with hyper IgD and periodic fever syndrome (MKD-HIDS). As previous findings indicated that the deficient MK activity in MKD impacts protein prenylation in a temperature-sensitive manner, we compared the subcellular localization and activation of the small Rho GTPases RhoA, Rac1 and Cdc42 in control, MKD-HIDS and MKD-MA fibroblasts cultured at physiological and elevated temperatures. This revealed a temperature-induced altered subcellular localization and activation in the MKD cells. To study if and how the temperature-induced ectopic activation of these signalling proteins affects cellular processes, we performed comparative transcriptome analysis of control and MKD-MA fibroblasts cultured at 37 °C or 40 °C. This identified cell cycle and actin cytoskeleton organization as respectively most down- and upregulated gene clusters. Further studies confirmed that these processes were affected in fibroblasts from both patients with MKD-MA and MKD-HIDS. Finally, we found that, similar to immune cells, the MK deficiency causes metabolic reprogramming in MKD fibroblasts resulting in increased expression of genes involved in glycolysis and the PI3K/Akt/mTOR pathway. We postulate that the ectopic activation of small GTPases causes inappropriate signalling contributing to the molecular and cellular aberrations observed in MKD.
Topics: Mevalonate Kinase Deficiency; Humans; Fibroblasts; Phosphotransferases (Alcohol Group Acceptor); Cells, Cultured; Signal Transduction
PubMed: 38636615
DOI: 10.1016/j.bbadis.2024.167177 -
International Ophthalmology Apr 2024This review examined existing literature to determine various ocular manifestations of liver pathologies, with a focus on metabolic deficiencies as well as viral and... (Review)
Review
PURPOSE
This review examined existing literature to determine various ocular manifestations of liver pathologies, with a focus on metabolic deficiencies as well as viral and immune liver conditions.
METHODS
Recent data were compiled from PubMed from 2000 to 2020 using keywords that were relevant to the assessed pathologies. Ocular presentations of several liver pathologies were researched and then summarized in a comprehensive form.
RESULTS
Several ocular manifestations of liver disease were related to vitamin A deficiency, as liver disease is associated with impaired vitamin A homeostasis. Alcoholic liver cirrhosis can result in vitamin A deficiency, presenting with Bitot spots, xerosis, and corneal necrosis. Congenital liver diseases such as mucopolysaccharidoses and peroxisomal disorders are also linked with ocular signs. Viral causes of liver disease have associations with conditions like retinal vasculitis, keratoconjunctivitis sicca, retinopathies, Mooren's ulcer, and Sjogren's syndrome. Autoimmune hepatitis has been linked to peripheral ulcerative keratitis and uveitis.
CONCLUSIONS
Building strong associations between ocular and liver pathology will allow for early detection of such conditions, leading to the early implementation of management strategies. While this review outlines several of the existing connections between hepatic and ophthalmic disease, further research is needed in the area in order to strengthen these associations.
Topics: Humans; Vitamin A Deficiency; Keratoconjunctivitis Sicca; Corneal Ulcer; Sjogren's Syndrome; Dry Eye Syndromes; Liver Diseases; Retinal Vasculitis
PubMed: 38622271
DOI: 10.1007/s10792-024-03103-y -
Arthritis Research & Therapy Apr 2024Our study aimed to provide real-world evidence on the treatment patterns, effectiveness and safety of canakinumab in France in Familial Mediterranean Fever (FMF),...
BACKGROUND
Our study aimed to provide real-world evidence on the treatment patterns, effectiveness and safety of canakinumab in France in Familial Mediterranean Fever (FMF), Mevalonate Kinase Deficiency (MKD), and Tumor necrosis factor Receptor Associated Periodic Syndrome (TRAPS).
METHODS
This study used the JIR cohort, a multicentre international registry created in 2013 to collect data on patients with juvenile inflammatory rheumatic diseases. French patients diagnosed with FMF, MKD or TRAPS and treated with canakinumab were included in this study.
RESULTS
31 FMF, 26 MKD and 7 TRAPS patients received canakinumab during the study period. Most of them initiated canakinumab at the recommended dose of 2 mg/kg or 150 mg, but less than half of FMF and MKD patients initiated it at the recommended frequency (every 4 weeks). Two years after initiation, the rate of patients still on treatment was 78.1% in FMF, 73.7% in MKD, and 85.7% in TRAPS patients. While the dose per injection remained globally the same over the course of the treatment, some adjustments of the dose intervals were observed. Six patients had a severe adverse event reported. Of those, three were possibly related to canakinumab.
CONCLUSION
This interim analysis showed a good maintenance of canakinumab treatment 2 years after initiation and confirmed its safety profile in real-life practice in France in patients diagnosed with FMF, MKD and TRAPS. The high variety of dose and interval combinations observed in canakinumab treated patients let suppose that physicians adapt the posology to individual situations rather than a fixed treatment plan.
Topics: Humans; Hereditary Autoinflammatory Diseases; Familial Mediterranean Fever; Antibodies, Monoclonal, Humanized; Mevalonate Kinase Deficiency; Syndrome
PubMed: 38589954
DOI: 10.1186/s13075-024-03316-7 -
Frontiers in Immunology 2024Bi-allelic pathogenic variants in the gene, which encodes mevalonate kinase (MK), an essential enzyme in isoprenoid biosynthesis, cause the autoinflammatory metabolic...
OBJECTIVE
Bi-allelic pathogenic variants in the gene, which encodes mevalonate kinase (MK), an essential enzyme in isoprenoid biosynthesis, cause the autoinflammatory metabolic disorder mevalonate kinase deficiency (MKD). We generated and characterized MK-deficient monocytic THP-1 cells to identify molecular and cellular mechanisms that contribute to the pro-inflammatory phenotype of MKD.
METHODS
Using CRISPR/Cas9 genome editing, we generated THP-1 cells with different MK deficiencies mimicking the severe (MKD-MA) and mild end (MKD-HIDS) of the MKD disease spectrum. Following confirmation of previously established disease-specific biochemical hallmarks, we studied the consequences of the different MK deficiencies on LPS-stimulated cytokine release, glycolysis versus oxidative phosphorylation rates, cellular chemotaxis and protein kinase activity.
RESULTS
Similar to MKD patients' cells, MK deficiency in the THP-1 cells caused a pro-inflammatory phenotype with a severity correlating with the residual MK protein levels. In the MKD-MA THP-1 cells, MK protein levels were barely detectable, which affected protein prenylation and was accompanied by a profound pro-inflammatory phenotype. This included a markedly increased LPS-stimulated release of pro-inflammatory cytokines and a metabolic switch from oxidative phosphorylation towards glycolysis. We also observed increased activity of protein kinases that are involved in cell migration and proliferation, and in innate and adaptive immune responses. The MKD-HIDS THP-1 cells had approximately 20% residual MK activity and showed a milder phenotype, which manifested mainly upon LPS stimulation or exposure to elevated temperatures.
CONCLUSION
MK-deficient THP-1 cells show the biochemical and pro-inflammatory phenotype of MKD and are a good model to study underlying disease mechanisms and therapeutic options of this autoinflammatory disorder.
Topics: Humans; Lipopolysaccharides; THP-1 Cells; Phenotype; Mevalonate Kinase Deficiency; Oxidative Phosphorylation; Phosphotransferases (Alcohol Group Acceptor)
PubMed: 38550596
DOI: 10.3389/fimmu.2024.1379220 -
Orphanet Journal of Rare Diseases Mar 2024Although the pathology of X-linked adrenoleukodystrophy (ALD) is well described, it represents the end-stage of neurodegeneration. It is still unclear what cell types... (Review)
Review
Although the pathology of X-linked adrenoleukodystrophy (ALD) is well described, it represents the end-stage of neurodegeneration. It is still unclear what cell types are initially involved and what their role is in the disease process. Revisiting the seminal post-mortem studies from the 1970s can generate new hypotheses on pathophysiology. This review describes (histo)pathological changes of the brain and spinal cord in ALD. It aims at integrating older works with current insights and at providing an overarching theory on the pathophysiology of ALD. The data point to an important role for axons and glia in the pathology of both the myelopathy and leukodystrophy of ALD. In-depth pathological analyses with new techniques could help further unravel the sequence of events behind the pathology of ALD.
Topics: Humans; Adrenoleukodystrophy; Spinal Cord Diseases; Axons
PubMed: 38549180
DOI: 10.1186/s13023-024-03105-0 -
Orphanet Journal of Rare Diseases Mar 2024Adrenoleukodystrophy (ALD) is a multifaceted, X-linked, neurodegenerative disorder that comprises several clinical phenotypes. ALD affects patients through a variety of...
BACKGROUND
Adrenoleukodystrophy (ALD) is a multifaceted, X-linked, neurodegenerative disorder that comprises several clinical phenotypes. ALD affects patients through a variety of physical, emotional, social, and other disease-specific factors that collectively contribute to disease burden. To facilitate clinical care and research, it is important to identify which symptoms are most common and relevant to individuals with any subtype of ALD.
METHODS
We conducted semi-structured qualitative interviews and an international cross-sectional study to determine the most prevalent and important symptoms of ALD. Our study included adult participants with a diagnosis of ALD who were recruited from national and international patient registries. Responses were categorized by age, sex, disease phenotype, functional status, and other demographic and clinical features.
RESULTS
Seventeen individuals with ALD participated in qualitative interviews, providing 1709 direct quotes regarding their symptomatic burden. One hundred and nine individuals participated in the cross-sectional survey study, which inquired about 182 unique symptoms representing 24 distinct symptomatic themes. The symptomatic themes with the highest prevalence in the overall ALD sample cohort were problems with balance (90.9%), limitations with mobility or walking (87.3%), fatigue (86.4%), and leg weakness (86.4%). The symptomatic themes with the highest impact scores (on a 0-4 scale with 4 being the most severe) were trouble getting around (2.35), leg weakness (2.25), and problems with balance (2.21). A higher prevalence of symptomatic themes was associated with functional disability, employment disruption, and speech impairment.
CONCLUSIONS
There are many patient-relevant symptoms and themes that contribute to disease burden in individuals with ALD. These symptoms, identified by those having ALD, present key targets for further research and therapeutic development.
Topics: Adult; Humans; Cross-Sectional Studies; Adrenoleukodystrophy; Phenotype; Surveys and Questionnaires; Patient Reported Outcome Measures
PubMed: 38504253
DOI: 10.1186/s13023-024-03129-6 -
Epilepsy & Behavior Reports 2024Zellweger Syndrome is a peroxisomal disorder that can lead to elevation of long chain fatty acids and epilepsy, which can be drug resistant. The treatment of drug...
Zellweger Syndrome is a peroxisomal disorder that can lead to elevation of long chain fatty acids and epilepsy, which can be drug resistant. The treatment of drug resistant epilepsy can include the ketogenic diet in appropriately chosen patients. Typically, the ketogenic diet is contraindicated in individuals with defects in fatty acid metabolism because of the diet's reliance on medium and long chain fatty acids. To our knowledge this is the first publication outlining the use of the ketogenic diet in patients with defects in beta oxidation of very long chain fatty acids. We present two patients with Zellweger Syndrome who were placed on a ketogenic diet for drug resistant epilepsy. Safety and tolerance of the ketogenic diet in patients with Zellweger Syndrome.
PubMed: 38501062
DOI: 10.1016/j.ebr.2024.100655 -
Bioinformatics and Biology Insights 2024D-amino acid oxidase (DAO) is a flavoenzyme that metabolizes D-amino acids by oxidative deamination, producing hydrogen peroxide (HO) as a by-product. The generation of...
D-amino acid oxidase (DAO) is a flavoenzyme that metabolizes D-amino acids by oxidative deamination, producing hydrogen peroxide (HO) as a by-product. The generation of intracellular HO may alter the redox-homeostasis mechanism of cells and increase the oxidative stress levels in tissues, associated with the pathogenesis of age-related diseases and organ decline. This study investigates the effect of DAO knockdown using clustered regularly interspaced short palindromic repeats (CRISPR) through an approach on its protein-protein interactions (PPIs) and their potential roles in the process of aging. The target sequence and guide RNA of DAO were designed using the CCTop database, PPI analysis using the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) database, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses, Reactome biological pathway, protein docking using GalaxyTongDock database, and structure analysis. The translated target sequence of DAO lies between amino acids 43 to 50. The 10 proteins that were predicted to interact with DAO are involved in peroxisome pathways such as acyl-coenzyme A oxidase 1 (ACOX1), alanine-glyoxylate and serine-pyruvate aminotransferase (AGXT), catalase (CAT), carnitine O-acetyltransferase (CRAT), glyceronephosphate O-acyltransferase (GNPAT), hydroxyacid oxidase 1 (HAO1), hydroxyacid oxidase 2 (HAO2), trans-L-3-hydroxyproline dehydratase (L3HYPDH), polyamine oxidase (PAOX), and pipecolic acid and sarcosine oxidase (PIPOX). In summary, DAO mutation would most likely reduce activity with its interacting proteins that generate HO. However, DAO mutation may result in peroxisomal disorders, and thus, alternative techniques should be considered for an approach.
PubMed: 38425413
DOI: 10.1177/11779322241234772 -
European Journal of Medical Genetics Apr 2024The PEX11β gene contains four exons and encodes peroxisomal membrane protein 11β, which is involved in peroxisome proliferation and division. Pathogenic variants in...
The PEX11β gene contains four exons and encodes peroxisomal membrane protein 11β, which is involved in peroxisome proliferation and division. Pathogenic variants in this gene result in a rare genetic disorder with autosomal recessive inheritance called peroxisome biogenesis disorder 14B (MIM: 614920). Here, we report two affected siblings with a novel variant (NM_003846: c.11G > A, p. Trp4Ter) in the PEX11β gene that was identified by whole exome sequencing and confirmed by Sanger sequencing. The proband is a 22-year-old Iranian female who was born to consanguineous parents. The homozygous variant (NM_003846: c.11G > A, p. Trp4Ter) in the PEX11β gene was identified in the proband, who presented with cataracts, strabismus, nystagmus, intellectual disability, developmental delay, speech disorders, dry skin, and behavioral problems. Her younger affected brother, who had the same homozygous variant, suffered from similar but slightly milder symptoms. This paper reports the seventh family in the world with novel pathogenic variants in the PEX11β gene as the cause of peroxisome biogenesis disorder 14B. Additionally, the phenotypes of the previously reported patients are reviewed. Some of the phenotypes, such as bilateral congenital cataracts and intellectual disability, were present in all patients. However, other observed symptoms in previous cases, such as abnormal gait, myopia, abnormal muscle strength, hearing loss, gastrointestinal problems, skeletal disorders, and seizures, were not observed in the patients of this study. Further studies on this disorder could be valuable in determining the precise phenotype characteristics of this disease.
Topics: Female; Male; Humans; Young Adult; Adult; Siblings; Iran; Family; Cataract; Intellectual Disability; Membrane Proteins; Peroxisomal Disorders
PubMed: 38423277
DOI: 10.1016/j.ejmg.2024.104928