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Molecular and Cellular Probes Aug 2018Peroxisomes catalyze a number of essential metabolic functions of which fatty acid alpha- and beta-oxidation, ether phospholipid biosynthesis, glyoxylate detoxification... (Review)
Review
Peroxisomes catalyze a number of essential metabolic functions of which fatty acid alpha- and beta-oxidation, ether phospholipid biosynthesis, glyoxylate detoxification and bile acid synthesis are the most important. The key role of peroxisomes in humans is exemplified by the existence of a group of peroxisomal disorders, caused by mutations in > 30 different genes which code for proteins with a role in either peroxisome biogenesis or one of the metabolic pathways in peroxisomes. Technological advances in laboratory methods at the metabolite-, enzyme-, and molecular level have not only allowed the identification of new peroxisomal disorders but also new phenotypes associated with already identified genetic defects thus extending the clinical spectrum. Unfortunately, progress in the field of pathogenesis and treatment has lagged behind although there are certainly new and hopeful developments with respect to X-linked adrenoleukodystrophy and hyperoxaluria type 1.
Topics: Biomarkers; Humans; Models, Biological; Organelle Biogenesis; Peroxisomal Disorders
PubMed: 29438773
DOI: 10.1016/j.mcp.2018.02.001 -
Orphanet Journal of Rare Diseases Jul 2022Pathogenic variants in PEX-genes can affect peroxisome assembly and function and cause Zellweger spectrum disorders (ZSDs), characterized by variable phenotypes in terms...
BACKGROUND
Pathogenic variants in PEX-genes can affect peroxisome assembly and function and cause Zellweger spectrum disorders (ZSDs), characterized by variable phenotypes in terms of disease severity, age of onset and clinical presentations. So far, defects in at least 15 PEX-genes have been implicated in Mendelian diseases, but in some of the ultra-rare ZSD subtypes genotype-phenotype correlations and disease mechanisms remain elusive.
METHODS
We report five families carrying biallelic variants in PEX13. The identified variants were initially evaluated by using a combination of computational approaches. Immunofluorescence and complementation studies on patient-derived fibroblasts were performed in two patients to investigate the cellular impact of the identified mutations.
RESULTS
Three out of five families carried a recurrent p.Arg294Trp non-synonymous variant. Individuals affected with PEX13-related ZSD presented heterogeneous clinical features, including hypotonia, developmental regression, hearing/vision impairment, progressive spasticity and brain leukodystrophy. Computational predictions highlighted the involvement of the Arg294 residue in PEX13 homodimerization, and the analysis of blind docking predicted that the p.Arg294Trp variant alters the formation of dimers, impairing the stability of the PEX13/PEX14 translocation module. Studies on muscle tissues and patient-derived fibroblasts revealed biochemical alterations of mitochondrial function and identified mislocalized mitochondria and a reduced number of peroxisomes with abnormal PEX13 concentration.
CONCLUSIONS
This study expands the phenotypic and mutational spectrum of PEX13-related ZSDs and also highlight a variety of disease mechanisms contributing to PEX13-related clinical phenotypes, including the emerging contribution of secondary mitochondrial dysfunction to the pathophysiology of ZSDs.
Topics: Genetic Association Studies; Humans; Membrane Proteins; Mutation; Peroxisomes; Zellweger Syndrome
PubMed: 35854306
DOI: 10.1186/s13023-022-02415-5 -
Molecular Genetics and Metabolism Jul 2021In Zellweger syndrome (ZS), lack of peroxisome function causes physiological and developmental abnormalities in many organs such as the brain, liver, muscles, and...
In Zellweger syndrome (ZS), lack of peroxisome function causes physiological and developmental abnormalities in many organs such as the brain, liver, muscles, and kidneys, but little is known about the exact pathogenic mechanism. By disrupting the zebrafish pex2 gene, we established a disease model for ZS and found that it exhibits pathological features and metabolic changes similar to those observed in human patients. By comprehensive analysis of the fatty acid profile, we found organ-specific accumulation and reduction of distinct fatty acid species, such as an accumulation of ultra-very-long-chain polyunsaturated fatty acids (ultra-VLC-PUFAs) in the brains of pex2 mutant fish. Transcriptome analysis using microarray also revealed mutant-specific gene expression changes that might lead to the symptoms, including reduction of crystallin, troponin, parvalbumin, and fatty acid metabolic genes. Our data indicated that the loss of peroxisomes results in widespread metabolic and gene expression changes beyond the causative peroxisomal function. These results suggest the genetic and metabolic basis of the pathology of this devastating human disease.
Topics: Animals; Disease Models, Animal; Fatty Acids; Female; Gene Expression; Gene Expression Profiling; Humans; Liver; Male; Peroxins; Peroxisomes; Zebrafish; Zellweger Syndrome
PubMed: 34016526
DOI: 10.1016/j.ymgme.2021.05.002 -
Translational Pediatrics Jul 2021Zellweger syndrome (ZS) is commonly manifested as facial deformities, hypotonia, and liver dysfunction. However, ZS caused by gene mutation shows a broad and dispersed...
BACKGROUND
Zellweger syndrome (ZS) is commonly manifested as facial deformities, hypotonia, and liver dysfunction. However, ZS caused by gene mutation shows a broad and dispersed clinical pattern. In this study, the gene in ZS was analyzed to enrich its clinical characteristics. Meanwhile, phenotypic and genotypic characteristics of Zellweger spectrum disorder (ZSD) induced by mutation were evaluated.
METHODS
The clinical data of newborn with ZS in our hospital were analyzed retrospectively. We performed WES and found that the infant carried the gene variant. We searched the biomedical literature databases (PubMed, Web of Science, and EMBASE) to compare clinical features and genotypes.
RESULTS
The neonate developed facial deformities, hypotonia, feeding difficulties, and seizures. Her homozygous variant was found in the gene (NM_017929: exon2: c.34del) inherited from both parents. Electronic databases, including our case, reported 32 pathogenic variants in . We found that variation c.292C> T accounted for the largest proportion of mutations (16/66, 24.24%). The proportion of deleterious mutations in ZS patients was significantly higher than that in NALD and IRD patients.
CONCLUSIONS
We identified pathogenic variations in the gene and expanded the known mutant spectrum. By comparing patients with mutations, the study determined that a significantly higher percentage of deleterious mutations in ZS was associated with severe clinical phenotypic characteristics.
PubMed: 34430430
DOI: 10.21037/tp-21-103 -
EMBO Reports Jan 2017PEX13 is an integral membrane protein on the peroxisome that regulates peroxisomal matrix protein import during peroxisome biogenesis. Mutations in PEX13 and other...
PEX13 is an integral membrane protein on the peroxisome that regulates peroxisomal matrix protein import during peroxisome biogenesis. Mutations in PEX13 and other peroxin proteins are associated with Zellweger syndrome spectrum (ZSS) disorders, a subtype of peroxisome biogenesis disorder characterized by prominent neurological, hepatic, and renal abnormalities leading to neonatal death. The lack of functional peroxisomes in ZSS patients is widely accepted as the underlying cause of disease; however, our understanding of disease pathogenesis is still incomplete. Here, we demonstrate that PEX13 is required for selective autophagy of Sindbis virus (virophagy) and of damaged mitochondria (mitophagy) and that disease-associated PEX13 mutants I326T and W313G are defective in mitophagy. The mitophagy function of PEX13 is shared with another peroxin family member PEX3, but not with two other peroxins, PEX14 and PEX19, which are required for general autophagy. Together, our results demonstrate that PEX13 is required for selective autophagy, and suggest that dysregulation of PEX13-mediated mitophagy may contribute to ZSS pathogenesis.
Topics: Animals; Autophagy; Cell Line; Gene Knockdown Techniques; Humans; Membrane Proteins; Mice; Mice, Transgenic; Mitochondria; Mitophagy; Peroxisomes; Protein Binding; Protein Transport; RNA, Small Interfering; Sindbis Virus; Ubiquitin-Protein Ligases; Zellweger Syndrome
PubMed: 27827795
DOI: 10.15252/embr.201642443 -
Euro Surveillance : Bulletin Europeen... Jan 2024BackgroundWomen are overrepresented among individuals with post-acute sequelae of SARS-CoV-2 infection (PASC). Biological (sex) as well as sociocultural (gender)...
BackgroundWomen are overrepresented among individuals with post-acute sequelae of SARS-CoV-2 infection (PASC). Biological (sex) as well as sociocultural (gender) differences between women and men might account for this imbalance, yet their impact on PASC is unknown.AimWe assessed the impact of sex and gender on PASC in a Swiss population.MethodOur multicentre prospective cohort study included 2,856 (46% women, mean age 44.2 ± 16.8 years) outpatients and hospitalised patients with PCR-confirmed SARS-CoV-2 infection.ResultsAmong those who remained outpatients during their first infection, women reported persisting symptoms more often than men (40.5% vs 25.5% of men; p < 0.001). This sex difference was absent in hospitalised patients. In a crude analysis, both female biological sex (RR = 1.59; 95% CI: 1.41-1.79; p < 0.001) and a score summarising gendered sociocultural variables (RR = 1.05; 95% CI: 1.03-1.07; p < 0.001) were significantly associated with PASC. Following multivariable adjustment, biological female sex (RR = 0.96; 95% CI: 0.74-1.25; p = 0.763) was outperformed by feminine gender-related factors such as a higher stress level (RR = 1.04; 95% CI: 1.01-1.06; p = 0.003), lower education (RR = 1.16; 95% CI: 1.03-1.30; p = 0.011), being female and living alone (RR = 1.91; 95% CI: 1.29-2.83; p = 0.001) or being male and earning the highest income in the household (RR = 0.76; 95% CI: 0.60-0.97; p = 0.030).ConclusionSpecific sociocultural parameters that differ in prevalence between women and men, or imply a unique risk for women, are predictors of PASC and may explain, at least in part, the higher incidence of PASC in women. Once patients are hospitalised during acute infection, sex differences in PASC are no longer evident.
Topics: Female; Humans; Male; Adult; Middle Aged; COVID-19; Post-Acute COVID-19 Syndrome; Switzerland; Prospective Studies; SARS-CoV-2; Disease Progression
PubMed: 38214079
DOI: 10.2807/1560-7917.ES.2024.29.2.2300200 -
Neuropediatrics Aug 2016Peroxisomal disorders are a heterogeneous group of genetic metabolic disorders, caused by a defect in peroxisome biogenesis or a deficiency of a single peroxisomal... (Review)
Review
Peroxisomal disorders are a heterogeneous group of genetic metabolic disorders, caused by a defect in peroxisome biogenesis or a deficiency of a single peroxisomal enzyme. The peroxisomal disorders include the Zellweger spectrum disorders, the rhizomelic chondrodysplasia punctata spectrum disorders, X-linked adrenoleukodystrophy, and multiple single enzyme deficiencies. There are several core phenotypes caused by peroxisomal dysfunction that clinicians can recognize. The diagnosis is suggested by biochemical testing in blood and urine and confirmed by functional assays in cultured skin fibroblasts, followed by mutation analysis. This review describes the phenotype of the main peroxisomal disorders and possible pitfalls in (laboratory) diagnosis to aid clinicians in the recognition of this group of diseases.
Topics: Adrenoleukodystrophy; Age of Onset; Biomarkers; Chondrodysplasia Punctata, Rhizomelic; DNA Mutational Analysis; Genotype; Humans; Peroxisomal Disorders; Phenotype; Racemases and Epimerases; Refsum Disease; Zellweger Syndrome
PubMed: 27089543
DOI: 10.1055/s-0036-1582140 -
The European Respiratory Journal Oct 2020Major epidemics, including some that qualify as pandemics, such as severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), HIV, influenza A... (Review)
Review
Epidemic and pandemic viral infections: impact on tuberculosis and the lung: A consensus by the World Association for Infectious Diseases and Immunological Disorders (WAidid), Global Tuberculosis Network (GTN), and members of the European Society of Clinical Microbiology and Infectious Diseases...
Major epidemics, including some that qualify as pandemics, such as severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), HIV, influenza A (H1N1)pdm/09 and most recently COVID-19, affect the lung. Tuberculosis (TB) remains the top infectious disease killer, but apart from syndemic TB/HIV little is known regarding the interaction of viral epidemics and pandemics with TB. The aim of this consensus-based document is to describe the effects of viral infections resulting in epidemics and pandemics that affect the lung (MERS, SARS, HIV, influenza A (H1N1)pdm/09 and COVID-19) and their interactions with TB. A search of the scientific literature was performed. A writing committee of international experts including the European Centre for Disease Prevention and Control Public Health Emergency (ECDC PHE) team, the World Association for Infectious Diseases and Immunological Disorders (WAidid), the Global Tuberculosis Network (GTN), and members of the European Society of Clinical Microbiology and Infectious Diseases (ESCMID) Study Group for Mycobacterial Infections (ESGMYC) was established. Consensus was achieved after multiple rounds of revisions between the writing committee and a larger expert group. A Delphi process involving the core group of authors (excluding the ECDC PHE team) identified the areas requiring review/consensus, followed by a second round to refine the definitive consensus elements. The epidemiology and immunology of these viral infections and their interactions with TB are discussed with implications for diagnosis, treatment and prevention of airborne infections (infection control, viral containment and workplace safety). This consensus document represents a rapid and comprehensive summary on what is known on the topic.
Topics: BCG Vaccine; Betacoronavirus; COVID-19; Coronavirus Infections; Epidemics; HIV Infections; Humans; Influenza A Virus, H1N1 Subtype; Influenza, Human; Lung; Middle East Respiratory Syndrome Coronavirus; Pandemics; Pneumonia, Viral; Public Health; Respiratory Tract Infections; SARS-CoV-2; Severe Acute Respiratory Syndrome; Tuberculosis; Virus Diseases
PubMed: 32586885
DOI: 10.1183/13993003.01727-2020 -
Molecular Genetics and Metabolism Nov 2021Peroxisome Biogenesis Disorders-Zellweger spectrum disorder (PBD-ZSD) is a rare, autosomal recessive peroxisome biogenesis disorder that presents with variable symptoms.... (Review)
Review
Peroxisome Biogenesis Disorders-Zellweger spectrum disorder (PBD-ZSD) is a rare, autosomal recessive peroxisome biogenesis disorder that presents with variable symptoms. In patients with PBD-ZSD, pathogenic variants in the PEX family of genes disrupt normal peroxisomal function, impairing α- and β-oxidation of very-long-chain fatty acids and synthesis of bile acids, resulting in increased levels of toxic bile acid intermediates and multisystem organ damage. The spectrum of severity in PBD-ZSD is variable, with some patients dying in the first year of life, while others live into adulthood. Symptoms of mild PBD-ZSD include various combinations of developmental delay, craniofacial dysmorphic features, visual impairment, sensorineural hearing loss, liver disease, and adrenal insufficiency. Disease progression in mild PBD-ZSD is generally slow, and may include extended periods of stability in some cases. The presence and extent to which symptoms occur in mild PBD-ZSD represents a diagnostic challenge that can cause delays in diagnosis with potential significant implications related to disease monitoring and treatment. There is some support for the pharmacologic therapies of Lorenzo's oil, docosohexanoic acid, and batyl alcohol in altering symptoms; however, systematic long-term studies are lacking. Cholic acid (CA) therapy has demonstrated treatment efficacy in patients with PBD-ZSD, including decreased toxic bile acid intermediates, transaminase levels, and liver inflammation, with improvement in growth parameters. However, these responses are most apparent in patients diagnosed and treated at a young age. Advanced liver disease may limit the efficacy of CA, underscoring the need to diagnose and treat these patients before significant liver damage and other related complications occur. Here we discuss the signs and symptoms of PBD-ZSD in patients with mild disease, standard diagnostic tools, factors affecting disease management, and available pharmacological interventions.
Topics: Adult; Clinical Trials as Topic; Disease Management; Humans; Longitudinal Studies; Phenotype; Zellweger Syndrome
PubMed: 34625341
DOI: 10.1016/j.ymgme.2021.09.007 -
Pediatrics and Neonatology Dec 2017Zellweger syndrome (ZS) is a peroxisome biogenesis disorder attributed to a mutation of the PEX genes family. The incidence of this disease in Africa and the Arab world...
BACKGROUND
Zellweger syndrome (ZS) is a peroxisome biogenesis disorder attributed to a mutation of the PEX genes family. The incidence of this disease in Africa and the Arab world remains unknown. This contribution is aimed at describing the clinical phenotype and biochemical features in Tunisian patients with ZS in order to improve the detection and management of this severe disorder.
METHODS
A total of 52 patients diagnosed with ZS and 60 age- and sex-matched healthy controls were included in this study. Patients were recruited during the past 21 years, and the diagnosis of ZS was based on clinical and biochemical characteristics. Plasma very long chain fatty acids (VLCFA) were analyzed using capillary gas chromatography. The estimated incidence of ZS was calculated using the Hardy-Weinberg formula.
RESULTS
The estimated incidence of ZS is 1/15,898 in Tunisia. Age at diagnosis varied between 3 days and 18 months. Severe neurological syndrome, polymalformative features, and hepatodigestive signs were observed in 100%, 67.9%, and 32% of patients, respectively. Values for plasma C26:0 and C26:0/C22:0 and C24:0/C22:0 ratios were noticeably higher in ZS patients than in controls. Distributions of values were completely different for C26:0 (0.10-0.37 vs. 0.001-0.009), C26:0/C22:0 ratio (0.11-1.29 vs. 0.003-0.090), and C24:0/C22:0 ratio (1.03-3.18 vs. 0.4-0.90) in ZS patients versus controls, respectively.
CONCLUSIONS
This study highlights the high incidence of ZS in Tunisia and the possibility of simple and reliable biochemical diagnosis, thus permitting early genetic counseling for families at risk.
Topics: Fatty Acids; Female; Genetic Counseling; Humans; Infant; Infant, Newborn; Male; Tunisia; Zellweger Syndrome
PubMed: 28330580
DOI: 10.1016/j.pedneo.2016.08.011