scholarly journals Nuclear Factor Erythroid 2-Related Factor 2 Activation Might Mitigate Clinical Symptoms in Friedreich’s Ataxia: Clues of an “Out-Brain Origin” of the Disease From a Family Study

2021 ◽  
Vol 15 ◽  
Author(s):  
Sara Petrillo ◽  
Massimo Santoro ◽  
Piergiorgio La Rosa ◽  
Alessia Perna ◽  
Maria Giovanna Gallo ◽  
...  

Friedreich’s ataxia (FRDA) is the most frequent autosomal recessive ataxia in western countries, with a mean age of onset at 10–15 years. Patients manifest progressive cerebellar and sensory ataxia, dysarthria, lower limb pyramidal weakness, and other systemic manifestations. Previously, we described a family displaying two expanded GAA alleles not only in the proband affected by late-onset FRDA but also in the two asymptomatic family members: the mother and the younger sister. Both of them showed a significant reduction of frataxin levels, without any disease manifestation. Here, we analyzed if a protective mechanism might contribute to modulate the phenotype in this family. We particularly focused on the transcription factor nuclear factor erythroid 2-related factor 2 (NRF2), the first line of antioxidant defense in cells, and on the glutathione (GSH) system, an index of reactive oxygen species (ROS) detoxification ability. Our findings show a great reactivity of the GSH system to the frataxin deficiency, particularly in the asymptomatic mother, where the genes of GSH synthesis [glutamate–cysteine ligase (GCL)] and GSSG detoxification [GSH S-reductase (GSR)] were highly responsive. The GSR was activated even in the asymptomatic sister and in the proband, reflecting the need of buffering the GSSG increase. Furthermore, and contrasting the NRF2 expression documented in FRDA tissues, NRF2 was highly activated in the mother and in the younger sister, while it was constitutively low in the proband. This suggests that, also under frataxin depletion, the endogenous stimulation of NRF2 in asymptomatic FRDA subjects may contribute to protect against the progressive oxidative damage, helping to prevent the onset of neurological symptoms and highlighting an “out-brain origin” of the disease.

2019 ◽  
pp. practneurol-2019-002368 ◽  
Author(s):  
Conor Fearon ◽  
Roisin Lonergan ◽  
Damien Ferguson ◽  
Susan Byrne ◽  
David Bradley ◽  
...  

Friedreich’s ataxia is classically considered a disease with onset in the first or second decade. However, late-onset (age of onset 25–39 years) and very-late-onset (age of onset >40 years) forms do occur rarely. Misdiagnosis is common, particularly because the later onset forms of Friedreich’s ataxia commonly do not show characteristic features of the disorder (areflexia, dysarthria, sensory neuropathy, extensor plantars, amyotrophy, cardiac involvement, diabetes mellitus, scoliosis). Also, there may be atypical features such as spasticity, brisk reflexes and laryngeal dystonia. We present the clinical, imaging and genetic findings of a kindred with very-late-onset Friedreich’s ataxia and discuss the pitfalls and risk of misdiagnosis.


2021 ◽  
Vol 12 ◽  
Author(s):  
Alexander F. Brown ◽  
Michael H. Parkinson ◽  
Hector Garcia-Moreno ◽  
Ese Mudanohwo ◽  
Robyn Labrum ◽  
...  

Background: Patients with suspected genetic ataxia are often tested for Friedreich's ataxia (FRDA) and/or a variety of spinocerebellar ataxias (SCAs). FRDA can present with atypical, late-onset forms and so may be missed in the diagnostic process. We aimed to determine FRDA-positive subjects among two cohorts of patients referred to a specialist ataxia centre either for FRDA or SCA testing to determine the proportion of FRDA cases missed in the diagnostic screening process.Methods: 2000 SCA-negative ataxia patients, not previously referred for FRDA testing (group A), were tested for FRDA expansions and mutations. This group was compared with 1768 ataxia patients who had been previously referred for FRDA testing (group B) and were therefore more likely to have a typical presentation. The phenotypes of positive cases were assessed through review of the clinical case notes.Results: Three patients (0.2%) in group A had the FRDA expansion on both alleles, compared with 207 patients (11.7%) in group B. The heterozygous carrier rate across both cohorts was of 41 out of 3,768 cases (1.1%). The size of the expansions in the three FRDA-positive cases in group A was small, and their presentation atypical with late-onset.Conclusions: This study demonstrates that FRDA is very rare among patients who were referred purely for SCA testing without the clinical suspicion of FRDA. Such cases should be referred to specialist ataxia centres for more extensive testing to improve patient management and outcomes.


1994 ◽  
Vol 9 (6) ◽  
pp. 650-654 ◽  
Author(s):  
Joachim Hermsdöourfer ◽  
Karl Wessel ◽  
Norbert Mai ◽  
Christian Marquardt

Marine Drugs ◽  
2019 ◽  
Vol 17 (10) ◽  
pp. 552 ◽  
Author(s):  
Jiawen Zheng ◽  
Xiaoxiao Tian ◽  
Wen Zhang ◽  
Pingan Zheng ◽  
Fangfang Huang ◽  
...  

Fucoxanthin (Fx) is a natural extract from marine seaweed that has strong antioxidant activity and a variety of other bioactive effects. This study elucidated the protective mechanism of Fx on alcoholic liver injury. Administration of Fx was associated with lower pathological effects in liver tissue and lower serum marker concentrations for liver damage induced by alcohol. Fx also alleviated oxidative stress, and lowered the level of oxides and inflammation in liver tissue. Results indicate that Fx attenuated alcohol-induced oxidative lesions and inflammatory responses by activating the nuclear factor erythrocyte-2-related factor 2 (Nrf2)-mediated signaling pathway and down-regulating the expression of the toll-like receptor 4 (TLR4)-mediated nuclear factor-kappa B (NF-κB) signaling pathway, respectively. Our findings suggest that Fx can be developed as a potential nutraceutical for preventing alcohol-induced liver injury in the future.


Author(s):  
Mohammad Mehdi Heidari ◽  
Massoud Houshmand ◽  
Saman Hosseinkhani ◽  
Shahriar Nafissi ◽  
Mehri Khatami

Background:Friedreich's ataxia (FRDA) is an inherited recessive disorder characterized by progressive neurological disability and heart abnormalities. A deficiency in the protein frataxin causes this disease. Frataxin deficiency leads to progressive iron accumulation in mitochondria, excessive free radical production and dysfunction of respiratory chain complexes. The expansion (GAA) repeat in the first intron causes decreased frataxin expression by interfering with transcription.Methods:Activity of mitochondrial respiratory chain complex I (measured as NADH ferricyanide reductase) and intracellular ATP measurement was performed on lymphocyte of FRDA patients (n=12) and control subjects (n=25).Results:Our findings showed that complex I activity and intracellular ATP were significantly reduced (P=0.001) in patients compared with controls and we found strong correlation between complex I activity and intracellular ATP content in FRDA patients (r = 0.93; P<0.002). 8.6 and 9.0 kb deletion in mtDNA was detected in 9 patients out of 12 (75%) by multiplex polymerase chain reaction (PCR) and Southern blot analysis.Conclusions:This study suggested that a biochemical defect in complex I activity and ATP production, which may be due to iron accumulation in mitochondria, can be involved in age of onset of FRDA.


2019 ◽  
Vol 20 (20) ◽  
pp. 5211 ◽  
Author(s):  
Sara Petrillo ◽  
Jessica D’Amico ◽  
Piergiorgio La Rosa ◽  
Enrico Silvio Bertini ◽  
Fiorella Piemonte

NRF2 (Nuclear factor Erythroid 2-related Factor 2) signaling is impaired in Friedreich’s Ataxia (FRDA), an autosomal recessive disease characterized by progressive nervous system damage and degeneration of nerve fibers in the spinal cord and peripheral nerves. The loss of frataxin in patients results in iron sulfur cluster deficiency and iron accumulation in the mitochondria, making FRDA a fatal and debilitating condition. There are no currently approved therapies for the treatment of FRDA and molecules able to activate NRF2 have the potential to induce clinical benefits in patients. In this study, we compared the efficacy of six redox-active drugs, some already adopted in clinical trials, targeting NRF2 activation and frataxin expression in fibroblasts obtained from skin biopsies of FRDA patients. All of these drugs consistently increased NRF2 expression, but differential profiles of NRF2 downstream genes were activated. The Sulforaphane and N-acetylcysteine were particularly effective on genes involved in preventing inflammation and maintaining glutathione homeostasis, the dimethyl fumarate, omaxevolone, and EPI-743 in counteracting toxic products accumulation, the idebenone in mitochondrial protection. This study may contribute to develop synergic therapies, based on a combination of treatment molecules.


2001 ◽  
Vol 56 (5) ◽  
pp. 143-148 ◽  
Author(s):  
Lilian M. J. Albano ◽  
Mayana Zatz ◽  
A. Kim Chong ◽  
Débora Bertola ◽  
Sofia M. M. Sugayama ◽  
...  

INTRODUCTION: Friedreich's ataxia is a neurodegenerative disorder whose clinical diagnostic criteria for typical cases basically include: a) early age of onset (< 20 or 25 years), b) autosomal recessive inheritance, c) progressive ataxia of limbs and gait, and d) absence of lower limb tendon reflexes. METHODS: We studied the frequency and the size of expanded GAA and their influence on neurologic findings, age at onset, and disease progression in 25 Brazilian patients with clinical diagnosis of Friedreich's ataxia - 19 typical and 6 atypical - using a long-range PCR test. RESULTS: Abnormalities in cerebellar signs, in electrocardiography, and pes cavus occurred more frequently in typical cases; however, plantar response and speech were more frequently normal in this group when the both typical and atypical cases were compared. Homozygous GAA expansion repeats were detected in 17 cases (68%) - all typical cases. In 8 patients (32%) (6 atypical and 2 typical), no expansion was observed, ruling out the diagnosis of Friedreich's ataxia. In cases with GAA expansions, foot deformity, cardiac abnormalities, and some neurologic findings occurred more frequently; however, abnormalities in cranial nerves and in tomographic findings were detected less frequently than in patients without GAA expansions. DISCUSSION: Molecular analysis was imperative for the diagnosis of Friedreich's ataxia, not only for typical cases but also for atypical ones. There was no genotype-phenotype correlation. Diagnosis based only on clinical findings is limited; however, it aids in better screening for suspected cases that should be tested. Evaluation for vitamin E deficiency is recommended, especially in cases without GAA expansion.


2020 ◽  
Vol 21 (3) ◽  
pp. 916 ◽  
Author(s):  
Piergiorgio La Rosa ◽  
Enrico Silvio Bertini ◽  
Fiorella Piemonte

Friedreich’s ataxia (FA) is a trinucleotide repeats expansion neurodegenerative disorder, for which no cure or approved therapies are present. In most cases, GAA trinucleotide repetitions in the first intron of the FXN gene are the genetic trigger of FA, determining a strong reduction of frataxin, a mitochondrial protein involved in iron homeostasis. Frataxin depletion impairs iron–sulfur cluster biosynthesis and determines iron accumulation in the mitochondria. Mounting evidence suggests that these defects increase oxidative stress susceptibility and reactive oxygen species production in FA, where the pathologic picture is worsened by a defective regulation of the expression and signaling pathway modulation of the transcription factor NF-E2 p45-related factor 2 (NRF2), one of the fundamental mediators of the cellular antioxidant response. NRF2 protein downregulation and impairment of its nuclear translocation can compromise the adequate cellular response to the frataxin depletion-dependent redox imbalance. As NRF2 stability, expression, and activation can be modulated by diverse natural and synthetic compounds, efforts have been made in recent years to understand if regulating NRF2 signaling might ameliorate the pathologic defects in FA. Here we provide an analysis of the pharmaceutical interventions aimed at restoring the NRF2 signaling network in FA, elucidating specific biomarkers useful for monitoring therapeutic effectiveness, and developing new therapeutic tools.


Sign in / Sign up

Export Citation Format

Share Document