Expression data of MCK conditional frataxin knock-out mice
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE31208 | GEO | 2011/12/31
SECONDARY ACCESSION(S): PRJNA145983
REPOSITORIES: GEO
Similar Datasets
Project description:Frataxin deficiency in human is the cause of Friedreich's ataxia (FA), a lethal neuro- and cardio-degenerative disease. Knock-out (KO) mice of this mouse model of FA exhibit classical cardiomyopathy of the patients. The onset of FA phenotypes in the KO mice is approximately 6-7 weeks of age. This genearray analysis was conducted to examine the changes in gene expression in the heart of KO mice relative to their wild-type (WT) littermates at 4- and 10-weeks of age. At 10-weeks of age, the KO mice begin to die from severe cardiomyopathy. RNA from the heart of four female 4-week-old MCK littermates (two WT and two KO) and four female 10-week-old MCK littermates (two WT and two KO) was extracted and hybridised to Affymetrix Mouse Genome 430 2.0 Array.
2011-12-31 | E-GEOD-31208 | biostudies-arrayexpress
Project description:Functional genomic analysis of frataxin deficiency reveals tissue-specific alterations and identifies the PPARγ 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. Since the peroxisome proliferator-activated receptor gamma (PPARγ) pathway is known to regulate both processes, we hypothesized that dysregulation of this pathway could play a key role in frataxin deficiency. We confirmed this by showing a coordinate dysregulation of the PPARγ coactivator Pgc1a and transcription factor Srebp1 in cellular and animal models of frataxin deficiency, and in cells from FRDA patients, who have marked insulin resistance. Finally, we show that genetic modulation of the PPARγ pathway affects frataxin levels in vitro, supporting PPARγ as a novel therapeutic target in FRDA. To compare frataxin deficient (KIKO) mice vs. WT, heart, skeletal muscle, and liver.
2010-04-09 | E-GEOD-15848 | biostudies-arrayexpress
Project description:Functional genomic analysis of frataxin deficiency reveals tissue-specific alterations and identifies the PPARγ 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. Since the peroxisome proliferator-activated receptor gamma (PPARγ) pathway is known to regulate both processes, we hypothesized that dysregulation of this pathway could play a key role in frataxin deficiency. We confirmed this by showing a coordinate dysregulation of the PPARγ coactivator Pgc1a and transcription factor Srebp1 in cellular and animal models of frataxin deficiency, and in cells from FRDA patients, who have marked insulin resistance. Finally, we show that genetic modulation of the PPARγ pathway affects frataxin levels in vitro, supporting PPARγ as a novel therapeutic target in FRDA. To compare frataxin deficient (KIKO) mice vs. WT, heart and skeletal muscle. Three replicates (KIKO vs WT), with dye swap
2009-06-02 | E-GEOD-15843 | biostudies-arrayexpress
Project description:Functional genomic analysis of frataxin deficiency reveals tissue-specific alterations and identifies the PPARγ 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. Since the peroxisome proliferator-activated receptor gamma (PPARγ) pathway is known to regulate both processes, we hypothesized that dysregulation of this pathway could play a key role in frataxin deficiency. We confirmed this by showing a coordinate dysregulation of the PPARγ coactivator Pgc1a and transcription factor Srebp1 in cellular and animal models of frataxin deficiency, and in cells from FRDA patients, who have marked insulin resistance. Finally, we show that genetic modulation of the PPARγ pathway affects frataxin levels in vitro, supporting PPARγ as a novel therapeutic target in FRDA.
2009-06-02 | GSE15848 | GEO
Project description:Functional genomic analysis of frataxin deficiency reveals tissue-specific alterations and identifies the PPARγ 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. Since the peroxisome proliferator-activated receptor gamma (PPARγ) pathway is known to regulate both processes, we hypothesized that dysregulation of this pathway could play a key role in frataxin deficiency. We confirmed this by showing a coordinate dysregulation of the PPARγ coactivator Pgc1a and transcription factor Srebp1 in cellular and animal models of frataxin deficiency, and in cells from FRDA patients, who have marked insulin resistance. Finally, we show that genetic modulation of the PPARγ pathway affects frataxin levels in vitro, supporting PPARγ as a novel therapeutic target in FRDA.
2009-06-02 | GSE15843 | GEO
Project description:Friedreich's ataxia (FRDA), the most common inherited ataxia in humans, is caused by recessive mutations that lead to a substantial reduction in the levels of frataxin (FXN), a mitochondrial iron binding protein. FRDA is a multi-system disease, involving multiple neurological, cardiac, and metabolic manifestations whose study is hindered by a paucity of animal models that faithfully recapitulate human disease features. We developed an inducible (doxycycline) mouse model of Fxn deficiency (FRDAkd) that enabled us to control the onset, progression and potential rescue of disease phenotypes by the modulation of Fxn levels using RNA interference. We found that systemic knockdown of Fxn in adult mice led to multiple features paralleling those observed in human patients, including electrophysiological, cellular, biochemical and structural phenotypes associated with cardiomyopathy, as well as dorsal root ganglion and retinal neuronal degeneration and reduced axonal size and myelin sheath thickness in the spinal cord. Fxn knockdown mice also exhibited other abnormalities similar to patients, including weight loss, reduced locomotor activity, ataxia, reduced muscular strength, and reduced survival, as well as genome-wide transcriptome changes. We performed microarray analysis of heart, cerebellum and dorsal root ganglia in FRDAkd mouse model of frataxin deficiency, and found several molecular pathway dysfunction via genome-wide transcriptome analyses. We also found that, upon restoration of near wild-type FXN levels, we observed significant recovery of function, pathology and associated transcriptomic changes, even after significant motor dysfunction was observed. The rapidity of Fxn expression due to doxycycline removal and its robust correction of various parameters, even when restored after the onset of motor dysfunction, makes this FRDAkd mouse model an appealing potential preclinical tool for testing various therapeutics for FRDA.
2017-12-19 | GSE98790 | GEO
Project description:Friedreich ataxia is a neuro and cardio degenerative disease, caused by progressive, decreased expression of the frataxin gene (FXN). Hyperthrophic cardiomyopathy is the major cause of early mortality. We used four different lines of human, Induced Pluripotent Stem Cells derived- cardiomyocytes which were transfected with an siRNA against frataxin post-differentiation. Trascriptome analysis of cells in which frataxin was knocked down vs cells transfected with a si control RNA allowed the identification of novel pathways that may contribute to the pathogenesis of the disease.
2022-11-02 | E-MTAB-11296 | biostudies-arrayexpress
Project description:Friedreich's Ataxia (FRDA), a rare, inherited, progressive degenerative disease, is caused by a defective expression of mitochondrial protein frataxin (FXN), due to homozygous hyper-expansion of GAA triplets in the gene which severely reduce its transcription. FXN is crucial for cell survival and its deficiency in humans critically affects viability of neurons, cardiomyocytes and pancreatic beta cells. Around two thirds of individuals with FRDA show typical manifestation of hypertrophic cardiomyopathy, that can progress in heart failure and death. Except for FXN, very few genes have been correlated with ataxia and cardiac disease in FRDA. To identify other genes involved in pathogenesis of FRDA, a microarray analysis on FRDA patient's lymphoblastoid cells stably reconstituted with FXN was performed. HS-1 associated protein X-1 (HAX-1), a family of proteins playing important roles in the protection of cardiomyocytes from apoptosis, is the highest up-regulated transcript (FC=+2, p<0.0006). HAX-1 is highly expressed in heart and HAX-1 heterozygous-deficient hearts exhibit increases in infarct size. The microarray result was further assessed with qRT-PCR and western blot analysis performed on HEK293 stably transfected with empty vector or FXN-vector and lymphoblasts from FRDA patients compared to clinically unaffected heterozygous parents, confirming a strong co-expression of HAX-1 and FXN both at mRNA and protein level. Moreover, analysis of FXN and HAX-1 in peripheral blood mononuclear cells (PBMCs) of FRDA patients (n=13), heterozygous parents (n=6) and non-correlated healthy controls (n=13) revealed that their expressions are correlated. The positive correlation is more significant in FRDA patients showing a cardiac disease (10/13). The positive correlation between frataxin and HAX-1 expression level suggests a potential link of HAX-1 expression to pro-survival or protective cellular pathways related to frataxin. Thus, HAX-1 may be considered a specific biomarker of cardiomyopathy in FRDA and may represent a prognostic implement in these patients. Moreover, the discovery of novel genetic "risk" or "protective" factors in cardiomyopathy is crucial to improve risk stratification strategies and to identify new therapeutic targets.
2019-12-31 | GSE108200 | GEO
Project description:Background: Friedreich ataxia, an autosomal recessive neurodegenerative and cardiac disease, is caused by abnormally low levels of frataxin, an essential mitochondrial protein. All Friedreich ataxia patients carry a GAA/TTC repeat expansion in the first intron of the frataxin gene, either in the homozygous state or in compound heterozygosity with other loss-of-function mutations. The GAA expansion inhibits frataxin expression through a heterochromatin-mediated repression mechanism. Histone modifications that are characteristic of silenced genes in heterochromatic regions occur at expanded alleles in cells from Friedreich ataxia patients, including increased trimethylation of histone H3 at lysine 9 and hypoacetylation of histones H3 and H4. Methodology/Principal Findings: By chromatin immunoprecipitation, we detected the same heterochromatin marks in homozygous mice carrying a (GAA)230 repeat in the first intron of the mouse frataxin gene (KIKI mice). These animals have decreased frataxin levels and, by microarray analysis, show significant gene expression changes in several tissues. We treated KIKI mice with a novel histone deacetylase inhibitor, compound 106, which substantially increases frataxin mRNA levels in cells from Friedreich ataxia individuals. Treatment increased histone H3 and H4 acetylation in chromatin near the GAA repeat and restored wild-type frataxin levels in the nervous system and heart, as determined by quantitative RT-PCR and semiquantitative western blot analysis. No toxicity was observed. Furthermore, most of the differentially expressed genes in KIKI mice reverted towards wild-type levels. Conclusions/Significance: Lack of acute toxicity, normalization of frataxin levels and of the transcription profile changes resulting from frataxin deficiency provide strong support to a possible efficacy of this or related compounds in reverting the pathological process in Friedreich ataxia, a so far incurable neurodegenerative disease. Keywords: drug response
2008-03-08 | GSE10745 | GEO
Project description:Frataxin, a conserved mitochondrial protein involved in iron homeostasis, is reduced in patients with Friedreich’s ataxia (FRDA). Transcription profiling and DNA damage assays were performed on blood cells from FRDA patients. Altered expression patterns pertained to immune response, signaling pathways, transcription, apoptosis, and genotoxic stress response pathways. FRDA patients had significantly more mitochondrial and nuclear DNA damage than a control population. Frataxin mRNA levels correlated with age of onset and displayed unique sets of gene alterations involved in oxidative phosphorylation and protein synthesis. Thus analysis of blood in FRDA patients yields insight into the nature and progression of the disease, as well as potential therapeutic approaches. Keywords: Friedreich's ataxia; frataxin; mitochondrial DNA damage; nuclear DNA damage; genotoxic stress
2009-12-08 | GSE11204 | GEO