Oxidative and Electrophilic Stress Aggravate GFAP Dysfunction in Alexander Disease

2020 ◽  
Vol 159 ◽  
pp. S120
Author(s):  
Alvaro Viedma ◽  
Dolores Pérez-Sala ◽  
Maria Angeles Pajares
Author(s):  
Roberta Battini ◽  
Enrico Bertini ◽  
Roberta Milone ◽  
Chiara Aiello ◽  
Rosa Pasquariello ◽  
...  

Abstract PRUNE1-related disorders manifest as severe neurodevelopmental conditions associated with neurodegeneration, implying a differential diagnosis at birth with static encephalopathies, and later with those manifesting progressive brain damage with the involvement of both the central and the peripheral nervous system.Here we report on another patient with PRUNE1 (p.Asp106Asn) recurrent mutation, whose leukodystrophy, inferior olives hyperintensity, and macrocephaly led to the misleading clinical suspicion of Alexander disease. Clinical features, together with other recent descriptions, suggest avoiding the term “microcephaly” in defining this disorder that could be renamed “neurodevelopmental disorder with progressive encephalopathy, hypotonia, and variable brain anomalies” (NPEHBA).


2021 ◽  
pp. 355-360
Author(s):  
Tongjia Cai ◽  
Sisi Jing ◽  
Ying Li ◽  
Jianjun Wu

Adult-onset Alexander disease (AOAD) is an autosomal dominant progressive astrogliopathy caused by pathogenic variants in glial fibrillary acidic protein (<i>GFAP</i>). Individuals with this disorder often present with a typical neuroradiologic pattern, including frontal white matter abnormality with contrast enhancement, atrophy and signal intensity changes of the medulla oblongata and upper cervical cord on MRI. Focal lesions are rarely seen in AOAD, which causes concern for primary malignancies. This study aimed to present the case of a 37-year-old male patient initially diagnosed with an astrocytoma in the lateral ventricle that was later identified as GFAP mutation-confirmed AOAD. <i>GFAP</i> sequencing revealed a heterogeneous missense mutation point c.236G&#x3e;A. Hence, AOAD should be considered in patients with tumor-like lesion brain lesion in association with atrophy of medulla oblongata and upper cervical spinal cord, and frontal white matter abnormality with contrast enhancement.


2009 ◽  
Vol 76 (2) ◽  
pp. 195-197 ◽  
Author(s):  
Cagatay Ozturk ◽  
Mehmet Tezer ◽  
Omer Karatoprak ◽  
Azmi Hamzaoglu

2002 ◽  
Vol 24 (7) ◽  
pp. 723-726 ◽  
Author(s):  
Atsushi Imamura ◽  
Kenji E. Orii ◽  
Shinji Mizuno ◽  
Hiroaki Hoshi ◽  
Tomio Kondo

2012 ◽  
Vol 442 (3) ◽  
pp. 453-464 ◽  
Author(s):  
Ashlee Higdon ◽  
Anne R. Diers ◽  
Joo Yeun Oh ◽  
Aimee Landar ◽  
Victor M. Darley-Usmar

The process of lipid peroxidation is widespread in biology and is mediated through both enzymatic and non-enzymatic pathways. A significant proportion of the oxidized lipid products are electrophilic in nature, the RLS (reactive lipid species), and react with cellular nucleophiles such as the amino acids cysteine, lysine and histidine. Cell signalling by electrophiles appears to be limited to the modification of cysteine residues in proteins, whereas non-specific toxic effects involve modification of other nucleophiles. RLS have been found to participate in several physiological pathways including resolution of inflammation, cell death and induction of cellular antioxidants through the modification of specific signalling proteins. The covalent modification of proteins endows some unique features to this signalling mechanism which we have termed the ‘covalent advantage’. For example, covalent modification of signalling proteins allows for the accumulation of a signal over time. The activation of cell signalling pathways by electrophiles is hierarchical and depends on a complex interaction of factors such as the intrinsic chemical reactivity of the electrophile, the intracellular domain to which it is exposed and steric factors. This introduces the concept of electrophilic signalling domains in which the production of the lipid electrophile is in close proximity to the thiol-containing signalling protein. In addition, we propose that the role of glutathione and associated enzymes is to insulate the signalling domain from uncontrolled electrophilic stress. The persistence of the signal is in turn regulated by the proteasomal pathway which may itself be subject to redox regulation by RLS. Cell death mediated by RLS is associated with bioenergetic dysfunction, and the damaged proteins are probably removed by the lysosome-autophagy pathway.


2014 ◽  
Vol 23 (1) ◽  
pp. 1-2 ◽  
Author(s):  
Michael Brenner ◽  
Albee Messing

2014 ◽  
Vol 20 (2) ◽  
pp. 241-242 ◽  
Author(s):  
José Luiz Pedroso ◽  
Salmo Raskin ◽  
Orlando Graziani Povoas Barsottini ◽  
Acary S.B. Oliveira

2018 ◽  
Vol 18 (6) ◽  
pp. 538-557 ◽  
Author(s):  
Soraya Sajadimajd ◽  
Mozafar Khazaei

Oxidative stress due to imbalance between ROS production and detoxification plays a pivotal role in determining cell fate. In response to the excessive ROS, apoptotic signaling pathway is activated to promote normal cell death. However, through deregulation of biomolecules, high amount of ROS promotes carcinogenesis in cells with defective signaling factors. In this line, NRF2 appears to be as a master regulator, which protects cells from oxidative and electrophilic stress. Nrf2 is an intracellular transcription factor that regulates the expression of a number of genes to encode anti-oxidative enzymes, detoxifying factors, anti-apoptotic proteins and drug transporters. Under normal condition, Nrf2 is commonly degraded in cytoplasm by interaction with Keap1 inhibitor as an adaptor for ubiquitination factors. However, high amount of ROS activates tyrosine kinases to dissociate Nrf2: Keap1 complex, nuclear import of Nrf2 and coordinated activation of cytoprotective gene expression. Nevertheless, deregulation of Nrf2 and/or Keap1 due to mutation and activated upstream oncogenes is associated with nuclear accumulation and constitutive activation of Nrf2 to protect cells from apoptosis and induce proliferation, metastasis and chemoresistance. Owning to the interplay of ROS and Nrf2 signaling pathways with carcinogenesis, Nrf2 modulation seems to be important in the personalization of cancer therapy.


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