Friedreich's ataxia: past, present and future.

Friedreich's ataxia (FRDA) is an autosomal recessive inherited disorder characterized by progressive gait and limb ataxia, dysarthria, areflexia, loss of vibratory and position sense, and a progressive motor weakness of central origin. Additional features include hypertrophic cardiomyopathy and diabetes. Large GAA repeat expansions in the first intron of the FXN gene are the most common mutation underlying FRDA.

PGC-1alpha down-regulation affects the antioxidant response in Friedreich's ataxia.

Background: Cells from individuals with Friedreich's ataxia (FRDA) show reduced activities of antioxidant enzymes and cannot up-regulate their expression when exposed to oxidative stress. This blunted antioxidant response may play a central role in the pathogenesis. We previously reported that Peroxisome Proliferator Activated Receptor Gamma (PPARgamma) Coactivator 1-alpha (PGC-1alpha), a transcriptional master regulator of mitochondrial biogenesis and antioxidant responses, is down-regulated in most cell types from FRDA patients and animal models.

Animal models of human cerebellar ataxias: a cornerstone for the therapies of the twenty-first century.

Cerebellar ataxias represent a group of disabling neurological disorders. Our understanding of the pathogenesis of cerebellar ataxias is continuously expanding. A considerable number of laboratory animals with neurological mutations have been reported and numerous relevant animal models mimicking the phenotype of cerebellar ataxias are becoming available.

Cerebellar ataxias.

Purpose Of Review: The term 'cerebellar ataxias' encompasses the various cerebellar disorders encountered during daily practice. Patients exhibit a cerebellar syndrome and can also present with pigmentary retinopathy, extrapyramidal movement disorders, pyramidal signs, cortical symptoms (seizures, cognitive impairment/behavioural symptoms), and peripheral neuropathy. The clinical diagnosis of subtypes of ataxias is complicated by the salient overlap of the phenotypes between genetic subtypes.

Functional genomic analysis of frataxin deficiency reveals tissue-specific alterations and identifies the PPARgamma pathway as a therapeutic target in Friedreich's ataxia.

Friedreich's ataxia (FRDA), the most common inherited ataxia, is characterized by focal neurodegeneration, diabetes mellitus and life-threatening cardiomyopathy. Frataxin, which is significantly reduced in patients with this recessive disorder, is a mitochondrial iron-binding protein, but how its deficiency leads to neurodegeneration and metabolic derangements is not known. We performed microarray analysis of heart and skeletal muscle in a mouse model of frataxin deficiency, and found molecular evidence of increased lipogenesis in skeletal muscle, and alteration of fiber-type composition in heart, consistent with insulin resistance and cardiomyopathy, respectively.

Friedreich's Ataxia: from the (GAA)n repeat mediated silencing to new promising molecules for therapy.

Friedreich's ataxia (FRDA) is a neurodegenerative disease due to a pathological expansion of a GAA triplet repeat in the first intron of the FXN gene encoding for the mitochondrial protein frataxin. The expansion is responsible for most cases of FRDA through the formation of a nonusual B-DNA structure and heterochromatin conformation that determine a direct transcriptional silencing and the subsequent reduction in frataxin expression. Among other functions, frataxin is an iron chaperone central for the assembly of iron-sulfur clusters in mitochondria; its reduction is associated with iron accumulation in mitochondria, increased cellular sensitivity to oxidative stress and cell damage.

PPAR-gamma agonist Azelaoyl PAF increases frataxin protein and mRNA expression: new implications for the Friedreich's ataxia therapy.

Friedreich's ataxia is a neurodegenerative disease due to frataxin deficiency, and thus, drugs increasing the frataxin amount are excellent candidates for therapy. By screening Gene Expression Omnibus profiles, we identified records showing a frataxin response to the peroxisome proliferator-activated receptors gamma (PPAR-gamma) agonist rosiglitazone. We decided to investigate the effect of the PPAR-gamma agonist Azelaoyl PAF on the frataxin protein and mRNA expression profile.

Recombinant human erythropoietin increases frataxin protein expression without increasing mRNA expression.

Friedreich's ataxia is an autosomal recessive neurodegenerative disease that is due to the loss of function of the frataxin protein. The molecular basis of this disease is still a matter of debate and treatments have so far focused on managing symptoms. Drugs that can increase the amount of frataxin protein offer a possible therapy for the disease.