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Biochimica Et Biophysica Acta May 2016The peroxisomal compartment in hepatocytes hosts several essential metabolic conversions. These are defective in peroxisomal disorders that are either caused by failure... (Review)
Review
The peroxisomal compartment in hepatocytes hosts several essential metabolic conversions. These are defective in peroxisomal disorders that are either caused by failure to import the enzymes in the organelle or by mutations in the enzymes or in transporters needed to transfer the substrates across the peroxisomal membrane. Hepatic pathology is one of the cardinal features in disorders of peroxisome biogenesis and peroxisomal β-oxidation although it only rarely determines the clinical fate. In mouse models of these diseases liver pathologies also occur, although these are not always concordant with the human phenotype which might be due to differences in diet, expression of enzymes and backup mechanisms. Besides the morphological changes, we overview the impact of peroxisome malfunction on other cellular compartments including mitochondria and the ER. We further focus on the metabolic pathways that are affected such as bile acid formation, and dicarboxylic acid and branched chain fatty acid degradation. It appears that the association between deregulated metabolites and pathological events remains unclear.
Topics: Animals; Disease Models, Animal; Endoplasmic Reticulum; Gene Expression Regulation; Humans; Liver; Membrane Proteins; Metabolic Networks and Pathways; Mice; Mitochondria, Liver; Mutation; Peroxisomal Disorders; Peroxisomes; Protein Isoforms; Protein Transport; Signal Transduction
PubMed: 26453805
DOI: 10.1016/j.bbamcr.2015.09.035 -
Biochimica Et Biophysica Acta May 2016Peroxisomes contain numerous enzymatic activities that are important for mammalian physiology. Patients lacking either all peroxisomal functions or a single enzyme or... (Review)
Review
Peroxisomes contain numerous enzymatic activities that are important for mammalian physiology. Patients lacking either all peroxisomal functions or a single enzyme or transporter function typically develop severe neurological deficits, which originate from aberrant development of the brain, demyelination and loss of axonal integrity, neuroinflammation or other neurodegenerative processes. Whilst correlating peroxisomal properties with a compilation of pathologies observed in human patients and mouse models lacking all or individual peroxisomal functions, we discuss the importance of peroxisomal metabolites and tissue- and cell type-specific contributions to the observed brain pathologies. This enables us to deconstruct the local and systemic contribution of individual metabolic pathways to specific brain functions. We also review the recently discovered variability of pathological symptoms in cases with unexpectedly mild presentation of peroxisome biogenesis disorders. Finally, we explore the emerging evidence linking peroxisomes to more common neurological disorders such as Alzheimer's disease, autism and amyotrophic lateral sclerosis.
Topics: ATPases Associated with Diverse Cellular Activities; Animals; Brain; Disease Models, Animal; Gene Expression Regulation; Humans; Membrane Proteins; Metabolic Networks and Pathways; Mice; Mutation; Peroxisomal Disorders; Peroxisomes; Protein Isoforms; Protein Transport; Synaptic Transmission
PubMed: 26686055
DOI: 10.1016/j.bbamcr.2015.12.005 -
Frontiers in Cell and Developmental... 2022Retina is rich in lipids and dyslipidemia causes retinal dysfunction and eye diseases. In retina, lipids are not only important membrane component in cells and... (Review)
Review
Retina is rich in lipids and dyslipidemia causes retinal dysfunction and eye diseases. In retina, lipids are not only important membrane component in cells and organelles but also fuel substrates for energy production. However, our current knowledge of lipid processing in the retina are very limited. Peroxisomes play a critical role in lipid homeostasis and genetic disorders with peroxisomal dysfunction have different types of ocular complications. In this review, we focus on the role of peroxisomes in lipid metabolism, including degradation and detoxification of very-long-chain fatty acids, branched-chain fatty acids, dicarboxylic acids, reactive oxygen/nitrogen species, glyoxylate, and amino acids, as well as biosynthesis of docosahexaenoic acid, plasmalogen and bile acids. We also discuss the potential contributions of peroxisomal pathways to eye health and summarize the reported cases of ocular symptoms in patients with peroxisomal disorders, corresponding to each disrupted peroxisomal pathway. We also review the cross-talk between peroxisomes and other organelles such as lysosomes, endoplasmic reticulum and mitochondria.
PubMed: 36187472
DOI: 10.3389/fcell.2022.982564 -
Cells Dec 2021X-linked adrenoleukodystrophy (ALD) is an inherited progressive neurometabolic disease caused by mutations in the gene and the accumulation of very long-chain fatty... (Review)
Review
X-linked adrenoleukodystrophy (ALD) is an inherited progressive neurometabolic disease caused by mutations in the gene and the accumulation of very long-chain fatty acids in plasma and tissues. Patients present with heterogeneous clinical manifestations which can include adrenal insufficiency, myelopathy, and/or cerebral demyelination. In the absence of a genotype-phenotype correlation, the clinical outcome of an individual cannot be predicted and currently there are no molecular markers available to quantify disease severity. Therefore, there is an unmet clinical need for sensitive biomarkers to monitor and/or predict disease progression and evaluate therapy efficacy. The increasing amount of biological sample repositories ('biobanking') as well as the introduction of newborn screening creates a unique opportunity for identification and evaluation of new or existing biomarkers. Here we summarize and review the many studies that have been performed to identify and improve knowledge surrounding candidate molecular biomarkers for ALD. We also highlight several shortcomings of ALD biomarker studies, which often include a limited sample size, no collection of longitudinal data, and no validation of findings in an external cohort. Nonetheless, these studies have generated a list of interesting biomarker candidates and this review aspires to direct future biomarker research.
Topics: ATP Binding Cassette Transporter, Subfamily D, Member 1; Adrenoleukodystrophy; Biomarkers; Genetic Diseases, X-Linked; Humans
PubMed: 34943935
DOI: 10.3390/cells10123427 -
Biochimica Et Biophysica Acta May 2016Peroxisomes are dynamic organelles that play an essential role in a variety of cellular catabolic and anabolic metabolic pathways, including fatty acid alpha- and... (Review)
Review
Peroxisomes are dynamic organelles that play an essential role in a variety of cellular catabolic and anabolic metabolic pathways, including fatty acid alpha- and beta-oxidation, and plasmalogen and bile acid synthesis. Defects in genes encoding peroxisomal proteins can result in a large variety of peroxisomal disorders either affecting specific metabolic pathways, i.e., the single peroxisomal enzyme deficiencies, or causing a generalized defect in function and assembly of peroxisomes, i.e., peroxisome biogenesis disorders. In this review, we discuss the clinical, biochemical, and genetic aspects of all human peroxisomal disorders currently known.
Topics: ATPases Associated with Diverse Cellular Activities; Fatty Acids; Gene Expression Regulation; Humans; Membrane Proteins; Metabolic Networks and Pathways; Mutation; Organelle Biogenesis; Oxidation-Reduction; Peroxisomal Disorders; Peroxisomes; Plasmalogens; Protein Isoforms; Protein Sorting Signals; Protein Transport; Signal Transduction
PubMed: 26611709
DOI: 10.1016/j.bbamcr.2015.11.015 -
Sleep Medicine Mar 2022X-linked adrenoleukodystrophy (ALD) is a neurodegenerative disease that causes progressive gait and balance problems. Leg discomfort, sleep disturbances, and pain...
OBJECTIVE/BACKGROUND
X-linked adrenoleukodystrophy (ALD) is a neurodegenerative disease that causes progressive gait and balance problems. Leg discomfort, sleep disturbances, and pain contribute to daily disability. We sought to investigate the prevalence and severity of Restless Legs Syndrome (RLS) in patients with ALD.
PATIENTS/METHODS
We administered questionnaires and conducted diagnostic telephone interviews to assess RLS severity. We retrospectively extracted data from neurological examinations, functional gait measures, and laboratory assessments.
RESULTS AND CONCLUSIONS
Thirty-two adults with ALD (21 female, 11 male) were recruited to participate. Thirteen patients (40.6%) had RLS (10/21 females and 3/11 males). The median age of RLS onset was 35 years [IQR = 22-54]. Patients with RLS had more signs and symptoms related to myelopathy, but not the brain demyelination seen in ALD. This pilot study suggests a high prevalence of RLS in adults with ALD, which may contribute to sleep problems and impair quality of life.
Topics: Adrenoleukodystrophy; Adult; Female; Humans; Male; Middle Aged; Neurodegenerative Diseases; Pilot Projects; Prevalence; Quality of Life; Restless Legs Syndrome; Retrospective Studies; Severity of Illness Index; Surveys and Questionnaires; Young Adult
PubMed: 35245789
DOI: 10.1016/j.sleep.2022.02.008 -
Annals of Indian Academy of Neurology 2022
PubMed: 35693670
DOI: 10.4103/aian.AIAN_486_21 -
Journal of Inherited Metabolic Disease Jul 2022X-linked adrenoleukodystrophy (ALD) results from ABCD1 gene mutations which impair Very Long Chain Fatty Acids (VLCFA; C26:0 and C24:0) peroxisomal import and...
X-linked adrenoleukodystrophy (ALD) results from ABCD1 gene mutations which impair Very Long Chain Fatty Acids (VLCFA; C26:0 and C24:0) peroxisomal import and β-oxidation, leading to accumulation in plasma and tissues. Excess VLCFA drives impaired cellular functions (e.g. disrupted mitochondrial function), inflammation, and neurodegeneration. Major disease phenotypes include: adrenomyeloneuropathy (AMN), progressive spinal cord axonal degeneration, and cerebral ALD (C-ALD), inflammatory white matter demyelination and degeneration. No pharmacological treatment is available to-date for ALD. Pioglitazone, an anti-diabetic thiazolidinedione, exerts potential benefits in ALD models. Its mechanisms are genomic (PPARγ agonism) and nongenomic (mitochondrial pyruvate carrier-MPC, long-chain acyl-CoA synthetase 4-ACSL4, inhibition). However, its use is limited by PPARγ-driven side effects (e.g. weight gain, edema). PXL065 is a clinical-stage deuterium-stabilized (R)-enantiomer of pioglitazone which lacks PPARγ agonism but retains MPC activity. Here, we show that incubation of ALD patient-derived cells (both AMN and C-ALD) and glial cells from Abcd1-null mice with PXL065 resulted in: normalization of elevated VLCFA, improved mitochondrial function, and attenuated indices of inflammation. Compensatory peroxisomal transporter gene expression was also induced. Additionally, chronic treatment of Abcd1-null mice lowered VLCFA in plasma, brain and spinal cord and improved both neural histology (sciatic nerve) and neurobehavioral test performance. Several in vivo effects of PXL065 exceeded those achieved with pioglitazone. PXL065 was confirmed to lack PPARγ agonism but retained ACSL4 activity of pioglitazone. PXL065 has novel actions and mechanisms and exhibits a range of potential benefits in ALD models; further testing of this molecule in ALD patients is warranted.
Topics: ATP Binding Cassette Transporter, Subfamily D, Member 1; ATP-Binding Cassette Transporters; Adrenoleukodystrophy; Animals; Deuterium; Fatty Acids; Fatty Acids, Nonesterified; Inflammation; Mice; Mice, Knockout; PPAR gamma; Pioglitazone
PubMed: 35510808
DOI: 10.1002/jimd.12510 -
Molecular Genetics and Metabolism Dec 2023X-linked adrenoleukodystrophy (XALD) is the most common leukodystrophy. It has an estimated incidence of around 1/17.000, and a variable phenotype. Following the passage... (Review)
Review
X-linked adrenoleukodystrophy (XALD) is the most common leukodystrophy. It has an estimated incidence of around 1/17.000, and a variable phenotype. Following the passage of Aidens Law, New York became the first state to implement a newborn screening for XALD in 2013. Since then, 38 American states, Taiwan, and the Netherlands have included XALD in their NBS program, and Japan and Italy have ongoing pilot studies. Screening for XALD allows for early, potentially lifesaving treatment of adrenal insufficiency and cerebral demyelination but is also a complex subject, due to our limited understanding of the natural history and lack of prognostic biomarkers. Screening protocols and algorithms vary between countries and states, and results and experiences gained so far are important for the future implementation of XALD NBS in other countries. In this review, we have examined the algorithms, methodologies, and outcomes used, as well as how common challenges are addressed in countries/states that have experience using NBS for XALD. We identified 14 peer-reviewed reports on NBS for XALD. All studies presented methods for detecting XALD at birth by NBS using a combination of mass spectrometry and ABCD1 gene sequencing. This has allowed for early surveillance of presymptomatic XALD patients, and the possibility for early detection and timely treatment of XALD manifestations. Obstacles to NBS for XALD include how to deal with variants of unknown significance, whether to screen females, and the ethical concerns of an NBS for a disease where we have limited understanding of natural history and phenotype/genotype correlation.
Topics: Infant, Newborn; Female; Humans; Adrenoleukodystrophy; Neonatal Screening; Adrenal Insufficiency; New York; Genetic Association Studies
PubMed: 37979237
DOI: 10.1016/j.ymgme.2023.107734 -
Biochemical and Biophysical Research... May 2018Mitochondria are constantly communicating with the rest of the cell. Defects in mitochondria underlie severe pathologies, whose mechanisms remain poorly understood. It... (Review)
Review
Mitochondria are constantly communicating with the rest of the cell. Defects in mitochondria underlie severe pathologies, whose mechanisms remain poorly understood. It is becoming increasingly evident that mitochondrial malfunction resonates in other organelles, perturbing their function and their biogenesis. In this manuscript, we review the current knowledge on the cross-talk between mitochondria and other organelles, particularly lysosomes, peroxisomes and the endoplasmic reticulum. Several organelle interactions are mediated by transcriptional programs, and other signaling mechanisms are likely mediating organelle dysfunction downstream of mitochondrial impairments. Many of these organelle crosstalk pathways are likely to have a role in pathological processes.
Topics: AMP-Activated Protein Kinases; Animals; Basic Helix-Loop-Helix Leucine Zipper Transcription Factors; Endoplasmic Reticulum; Gene Expression Regulation; Humans; Lysosomal Storage Diseases; Lysosomes; Mitochondria; Mitochondrial Diseases; Peroxisomes; Signal Transduction; Transcription, Genetic; Zellweger Syndrome
PubMed: 28456629
DOI: 10.1016/j.bbrc.2017.04.124