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Microglial cells ensure essential roles in brain homeostasis. In pathological condition, microglia adopt a common signature, called disease-associated microglial (DAM) signature, characterized by the loss of homeostatic genes and the induction of disease-associated genes. In X-linked adrenoleukodystrophy (X-ALD), the most common peroxisomal disease, microglial defect has been shown to precede myelin degradation and may actively contribute to the neurodegenerative process. We previously established BV-2 microglial cell models bearing mutations in peroxisomal genes that recapitulate some of the hallmarks of the peroxisomal β-oxidation defects such as very long-chain fatty acid (VLCFA) accumulation. In these cell lines, we used RNA-sequencing and identified large-scale reprogramming for genes involved in lipid metabolism, immune response, cell signaling, lysosome and autophagy, as well as a DAM-like signature. We highlighted cholesterol accumulation in plasma membranes and observed autophagy patterns in the cell mutants. We confirmed the upregulation or downregulation at the protein level for a few selected genes that mostly corroborated our observations and clearly demonstrated increased expression and secretion of DAM proteins in the BV-2 mutant cells. In conclusion, the peroxisomal defects in microglial cells not only impact on VLCFA metabolism but also force microglial cells to adopt a pathological phenotype likely representing a key contributor to the pathogenesis of peroxisomal disorders. [ABSTRACT FROM AUTHOR]

Microglial cells ensure essential roles in brain homeostasis. In pathological condition, microglia adopt a common signature, called disease-associated microglial (DAM) signature, characterized by the loss of homeostatic genes and the induction of disease-associated genes. In X-linked adrenoleukodystrophy (X-ALD), the most common peroxisomal disease, microglial defect has been shown to precede myelin degradation and may actively contribute to the neurodegenerative process. We previously established BV-2 microglial cell models bearing mutations in peroxisomal genes that recapitulate some of the hallmarks of the peroxisomal β-oxidation defects such as very long-chain fatty acid (VLCFA) accumulation. In these cell lines, we used RNA-sequencing and identified large-scale reprogramming for genes involved in lipid metabolism, immune response, cell signaling, lysosome and autophagy, as well as a DAM-like signature. We highlighted cholesterol accumulation in plasma membranes and observed autophagy patterns in the cell mutants. We confirmed the upregulation or downregulation at the protein level for a few selected genes that mostly corroborated our observations and clearly demonstrated increased expression and secretion of DAM proteins in the BV-2 mutant cells. In conclusion, the peroxisomal defects in microglial cells not only impact on VLCFA metabolism but also force microglial cells to adopt a pathological phenotype likely representing a key contributor to the pathogenesis of peroxisomal disorders.

Background: Up to 80% of women with X‐linked adrenoleukodystrophy (X‐ALD) develop symptoms of myelopathy and peripheral neuropathy during their lifetime. The study's objective was to compare symptomatic versus asymptomatic women with X‐ALD regarding their physical and mental well‐being and quality of life. Methods: Data were obtained from a prospective, international, cross‐sectional cohort study of women with X‐ALD recruited both clinically and population based. Symptoms, quality of life, and physical and mental co‐morbidities were assessed by questionnaires. Women were considered symptomatic if they reported any sign of myelopathy or peripheral neuropathy. Group differences between symptomatic versus asymptomatic women and between age groups were examined using χ2 tests for categorical and independent sample t tests or analysis of variance for continuous variables. Results: Complete data were available from N = 180 women (mean age: 51.2 ± 13.6 years, range: 18–85), of whom 71.7% were classified as symptomatic, with prevalence increasing with age. Symptomatic versus asymptomatic women reported poorer physical and mental health, with 26.4% meeting the criteria for a clinical depression, 73.6% reporting chronic pain, 80.6% sleeping disturbances, 38.2% sexual dysfunction, and 47.3% restless legs syndrome. Large group differences were found on the physical health, but not on the mental health component of quality of life, where symptomatic women only differed when controlling for having a boy affected by X‐ALD (small effect) and treatment frequency (medium effect). Conclusions: Symptomatic women with X‐ALD present with physical and psychological co‐morbidities significantly reducing individuals' quality of life. The findings emphasize the need to develop new multi‐disciplinary treatment options tailored to women's specific needs. [ABSTRACT FROM AUTHOR]

Abstract Background Up to 80% of women with X‐linked adrenoleukodystrophy (X‐ALD) develop symptoms of myelopathy and peripheral neuropathy during their lifetime. The study's objective was to compare symptomatic versus asymptomatic women with X‐ALD regarding their physical and mental well‐being and quality of life. Methods Data were obtained from a prospective, international, cross‐sectional cohort study of women with X‐ALD recruited both clinically and population based. Symptoms, quality of life, and physical and mental co‐morbidities were assessed by questionnaires. Women were considered symptomatic if they reported any sign of myelopathy or peripheral neuropathy. Group differences between symptomatic versus asymptomatic women and between age groups were examined using χ2 tests for categorical and independent sample t tests or analysis of variance for continuous variables. Results Complete data were available from N = 180 women (mean age: 51.2 ± 13.6 years, range: 18–85), of whom 71.7% were classified as symptomatic, with prevalence increasing with age. Symptomatic versus asymptomatic women reported poorer physical and mental health, with 26.4% meeting the criteria for a clinical depression, 73.6% reporting chronic pain, 80.6% sleeping disturbances, 38.2% sexual dysfunction, and 47.3% restless legs syndrome. Large group differences were found on the physical health, but not on the mental health component of quality of life, where symptomatic women only differed when controlling for having a boy affected by X‐ALD (small effect) and treatment frequency (medium effect). Conclusions Symptomatic women with X‐ALD present with physical and psychological co‐morbidities significantly reducing individuals’ quality of life. The findings emphasize the need to develop new multi‐disciplinary treatment options tailored to women's specific needs.

X-linked adrenoleukodystrophy (X-ALD) is a severe neurodegenerative disorder resulting from defective ABCD1 transport protein. ABCD1 mediates peroxisomal uptake of free very-long-chain fatty acids (VLCFA) as well as their CoA-esters. Consequently, VLCFA accumulate in patients' plasma and tissues, which is considered as pathogenic X-ALD triggering factor. Clinical symptoms are mostly manifested in neural tissues and adrenal gland. Here, we investigate astrocytes from wild-type control and a genetic X-ALD mouse model ( Abcd1 -knockout), exposed to supraphysiological VLCFA (C22:0, C24:0 and C26:0) concentrations. They exhibit multiple impairments of energy metabolism. Furthermore, brain mitochondria from Abcd1 −/− mice and wild-type control respond similarly to VLCFA with increased ROS generation, impaired oxidative ATP synthesis and diminished Ca 2 + uptake capacity, suggesting that a defective ABCD1 exerts no adaptive pressure on mitochondria. In contrast, astrocytes from Abcd1 −/− mice respond more sensitively to VLCFA than wild-type control astrocytes. Moreover, long-term application of VLCFA induces high ROS generation, and strong in situ depolarization of mitochondria, and, in Abcd1 −/− astrocytes, severely diminishes the capability to revert oxidized pyridine nucleotides to NAD(P)H. In addition, observed differences in responses of mitochondria and astrocytes to the hydrocarbon chain length of VLCFA suggest that detrimental VLCFA activities in astrocytes involve defective cellular functions other than mitochondria. In summary, we clearly demonstrate that VLCFA increase the vulnerability of Abcd1 −/− astrocytes. [ABSTRACT FROM AUTHOR]