Search Results (65)

Background: Friedreich’s ataxia (FRDA) is a neurodegenerative disorder driven by frataxin deficiency, resulting in mitochondrial dysfunction and reduced nuclear factor erythroid 2-related factor 2 (Nrf2) signaling. Pharmacologic trials have yielded inconsistent results, prompting an updated synthesis of evidence. Methods: We searched MEDLINE/PubMed, Google Scholar, Cochrane CENTRAL, ClinicalTrials.gov, and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) from database inception to 29 June 2025. Embase, Scopus and Web of Science were not searched due to institutional access limitations. Two reviewers independently screened studies, extracted data, and assessed risk of bias. Random-effects meta-analyses were conducted, and Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) was used. Primary outcomes were modified Friedreich Ataxia Rating Scale (mFARS)/Friedreich Ataxia Rating Scale (FARS); safety outcomes included adverse events (AEs) and serious AEs. Secondary outcomes were Scale for the Assessment and Rating of Ataxia (SARA), International Cooperative Ataxia Rating Scale (ICARS), Nine-Hole Peg Test, and the Timed 25-Foot Walk. Results: Sixteen studies (17 reports, n = 351) met inclusion criteria. Omaveloxolone was the only agent showing a statistically significant improvement in mFARS (mean difference (MD) −2.40; 95% confidence interval (CI) −4.24 to −0.56; p = 0.014), supported by low-certainty evidence. Other therapies showed no consistent benefit. Overall AE risk was comparable to control (risk ratio (RR) 1.00; 95% CI 0.98–1.03). Apparent subgroup differences by therapeutic class or age likely reflected drug-specific effects and small samples. Conclusions: Omaveloxolone was the only agent to reach statistical significance for mFARS and is the most promising and best-supported therapy among those reviewed; however, this rests on low-certainty evidence and needs confirmation in larger trials. No clear difference in overall adverse events was observed between intervention and control groups; however, available safety evidence remains limited by imprecision, small sample sizes, and short follow-up durations. Longer, standardized, and age-stratified randomized controlled trials (RCTs) are needed. Full article

Frataxin is a conserved mitochondrial protein essential for cellular iron–sulfur (Fe–S) cluster biogenesis and oxidative balance, with its deficiency causing Friedreich’s ataxia in humans. The hypomagnetic field (HMF), an environmental stressor known to influence oxidative stress and neurodevelopment, may interact with such inherent metabolic vulnerabilities. This study investigated whether HMF exposure exacerbates Fe–S homeostasis and oxidative disruption in a Drosophila melanogaster model of frataxin deficiency. Using synchrotron radiation-based X-ray fluorescence (SR-XRF) spectroscopy for in situ elemental analysis in live tissues, we found that HMF significantly altered iron distribution and content in a tissue-specific manner. In frataxin-silenced brains, HMF decreased iron distribution but increased total iron content, whereas in eyes it reduced iron content. Sulfur content decreased in frataxin-deficient eyes but increased in brains under HMF, though its spatial distribution was unchanged. Critically, HMF elevated reactive oxygen species (ROS) in frataxin-deficient brains. Transcriptomic analysis identified 202 differentially expressed genes under HMF in frataxin-silenced flies, including key regulators of iron metabolism and oxidative stress pathways. These findings demonstrate that HMF disrupts tissue-specific iron and sulfur homeostasis and intensifies oxidative stress in a frataxin-deficient insect system, underscoring its role as an environmental factor capable of aggravating metabolic fragility. Full article

Frataxin is a highly conserved mitochondrial protein that plays a key role in iron homeostasis and metabolism, and its deficiency leads to oxidative stress, mitochondrial dysfunction, and neurodegeneration. Hypomagnetic fields (HMF) can lead to various biological effects including increased oxidative stress, neurological and developmental disorders; yet, their effects acting as environmental stressors that exacerbate the inherent metabolic vulnerabilities in frataxin-deficient Drosophila melanogaster flies are still unknown. In this study, the bio-effects of HMF on growth, development, reproduction, and temperature stress resistance of frataxin-silenced flies were investigated. The results showed that HMF extended egg-to-adult and pupa developmental durations of both the control line of repo-GAL4; tub-GAL80^ts>GFP-RNAi (GFP-RNAi) and frataxin-deficient line of repo-GAL4; tub-GAL80^ts>fh RNAi (fh-RNAi) compared to those reared under a geomagnetic field (GMF). Compared with GMF, HMF significantly increased offspring fecundity in fh-RNAi flies, whereas the change in GFP-RNAi controls was not significant, while showing no significant effects on the adult weight of fh-RNAi flies. The impact of HMF on temperature stress resistance was particularly specific: it enhanced recovery from chill coma in control (GFP-RNAi) flies, while it accelerated recovery from heat shock in frataxin-silenced (fh-RNAi) flies. The mechanisms through which HMF modulate frataxin-associated phenotypes at a fundamental physical level warrant further investigation. Full article

Iron overload is a major pathological feature of β-thalassemia and a key driver of hepatic injury through oxidative stress and mitochondrial dysfunction. This study investigated the molecular effects of iron overload on liver mitochondria and evaluated the therapeutic potential of a deferiprone–resveratrol hybrid (DFP-RVT) in a β-thalassemia mouse model. Proteomic analysis was performed on liver tissues from baseline control, iron-overloaded, and DFP-RVT-treated mice to identify differentially expressed proteins and affected pathways. Iron overload resulted in marked downregulation of mitochondrial proteins, particularly components of oxidative phosphorylation and iron–sulfur cluster-associated pathways, including frataxin. In contrast, DFP-RVT treatment restored the expression of multiple mitochondrial proteins involved in respiratory chain function and energy metabolism. Comparative proteomic profiling revealed opposing regulation patterns between iron-overloaded and DFP-RVT-treated groups, indicating recovery of mitochondrial integrity following iron chelation therapy. These findings suggest that iron-induced hepatic injury in β-thalassemia is closely linked to mitochondrial protein dysregulation and that DFP-RVT may mitigate this process by restoring mitochondrial protein expression and iron homeostasis. This study provides mechanistic insight into iron-mediated mitochondrial dysfunction and supports the therapeutic potential of DFP-RVT for iron overload-associated liver injury. Full article

Hereditary ataxias are a heterogeneous group of disorders with overlapping clinical presentations but diverse genetic and molecular etiologies. Biomarkers are increasingly essential to improve diagnosis, refine prognosis, and accelerate the development of targeted therapies. Following PRISMA-ScR guidelines, we conducted a scoping review of PubMed and complementary sources (2010–2025) to map and describe the current landscape of genetic, imaging, fluid, electrophysiological, and digital biomarkers across the most prevalent hereditary ataxias, including SCA1, SCA2, SCA3, SCA6, SCA7, SCA17, SCA27B, dentatorubral–pallidoluysian atrophy (DRPLA), Friedreich’s ataxia (FRDA), RFC1-related ataxia (CANVAS), SPG7, and fragile X-associated tremor/ataxia syndrome (FXTAS). Eligible evidence encompassed observational cohorts, clinical trials, case series, and case reports providing primary biomarker data, with the objective of characterizing evidence breadth and identifying knowledge gaps rather than assessing comparative effectiveness. Across modalities, converging evidence highlights subtype-specific biomarker signatures. MRI volumetry, DTI, and FDG-PET map characteristic neurodegeneration patterns. Fluid biomarkers such as neurofilament light chain are informative across several SCAs and FRDA, while frataxin levels constitute robust endpoints in FRDA trials. Pathology-specific biomarkers such as ataxin-3 are advancing as tools for target engagement and may generalize to future gene-lowering strategies. Electrophysiological and oculographic measures show sensitivity for early disease detection, and wearable technologies are emerging as scalable tools for longitudinal monitoring. This scoping review synthesizes the heterogeneous evidence on hereditary ataxia biomarkers, highlighting multimodal frameworks that link molecular mechanisms with clinical endpoints. Mapping current approaches also reveals substantial variability and gaps across diseases and modalities, underscoring the need for harmonized validation in international multicenter cohorts and systematic integration into future clinical trials to advance precision medicine in hereditary ataxias. Full article

We explored the ability of the low molecular weight, polyphenol-rich fractions obtained from chestnut shells to inhibit ferroptosis in Friedreich Ataxia (FRDA), an inherited neuro- and cardio-degenerative disease. We prepared an aqueous extract by an eco-sustainable method and obtained a polyphenol-rich fraction (fraction D) of molecular weight less than 1.0 kDa after molecular size fractionation. The total phenols were 173.28 ± 4.97 μg gallic acid equivalents/mg fraction, and analysis by UHPLC-ITMSⁿ and RP-HPLC-UV revealed thirteen phenolic compounds with gallic acid and protocatechuic acid (PCA) as the most abundant (26.29 ± 2.19 and 4.93 ± 0.19 μg/mg fraction, respectively). Using a cellular assay based on patient-derived FRDA fibroblasts, we observed that chestnut shell dry extract at 20 µg/mL increased the survival of cells stressed with the ferroptosis inducer erastin from 8% to 45% and that this activity was dose-dependent. Fraction D at 20 µg/mL showed similar strong activity, increasing cell survival from 0.5% to 14% and decreasing lipid peroxidation by 42%. PCA, the most efficacious compound, doubled cell survival and decreased lipid peroxidation by 20%. Moreover, PCA increased the survival of cells in which frataxin was knocked down 1.5-fold and decreased ALOX12 expression. Our data suggest that PCA could be a promising molecule to explore FRDA pathophysiology. Full article

The pathogenesis of Friedreich’s ataxia (FRDA) remains poorly understood. The most important event is the deficiency of frataxin, a protein related to iron metabolism and, therefore, involved in oxidative stress. Studies on oxidative stress markers and gene expression in FRDA patients have yielded inconclusive results. This is largely due to the limited number of studies, small sample sizes, and methodological differences. A notable finding is the decreased activity of mitochondrial respiratory chain complexes I, II, and III, as well as aconitase, in endomyocardial tissue. In contrast, numerous studies in experimental models of FRDA (characterized by frataxin deficiency) have shown evidence of the involvement of oxidative stress in cellular degeneration. These findings include increased iron concentration, mitochondrial dysfunction (with reduced respiratory chain complex activity and membrane potential), and decreased aconitase activity. Additionally, there is the induction of antioxidant enzymes, reduced glutathione levels, elevated markers of lipoperoxidation, and DNA and carbonyl protein oxidation. The expression of NRF2 is decreased, along with the downregulation of PGC-1α. Therefore, it is plausible that antioxidant treatment may help improve symptoms and slow the progression of FRDA. Among the antioxidant treatments tested in FRDA patients, only omaveloxolone and, to a lesser extent, idebenone (particularly for cardiac hypertrophy) have shown some efficacy. However, many antioxidant drugs have shown the ability to reduce oxidative stress in experimental models of FRDA. Therefore, these drugs may be useful in treating FRDA and are likely candidates for future clinical trials. Future studies investigating oxidative stress and antioxidant therapies in FRDA should adopt a prospective, multicenter, long-term, double-blind design. Full article

Background/Objectives: Ribosomal Protein Lateral Stalk Subunit P2 (RPLP2), an important ribosomal protein, is mainly involved in modulating protein synthesis and plays an essential role in the carcinogenesis of many cancers. However, its precise impact on diffuse large B-cell lymphoma (DLBCL) remains unknown. Methods: This study utilized siRNA to knock down RPLP2, aiming to investigate its role in DLBCL progression. RT-qPCR and immunohistochemistry (IHC) were employed to assess RPLP2 and frataxin (FXN) expression levels in DLBCL. CCK8 and colony formation assays measured cell proliferation inhibition upon RPLP2 deletion, while transwell migration assays analyzed reduced cell motility. Lipid ROS and iron assays quantified ferroptosis markers to elucidate RPLP2’s regulation of FXN-mediated ferroptosis. Xenograft mouse models validated tumor suppression effects in vivo. Results: Here, we reveal that elevated RPLP2 expression is significantly correlated to unfavorable prognosis in DLBCL patients. In addition, we demonstrate that RPLP2 deletion dramatically reduces the cell proliferation and migration of DLBCL. Besides, knockdown of RPLP2 triggers ferroptosis via regulating ferroptosis suppressor FXN activity. Moreover, we discover that Destruxin b could target RPLP2 to suppress the development of DLBCL. Lastly, the combination of Destruxin b with Dox remarkably improves the anti-tumor effect. Conclusions: In general, the present study reveals the oncogenic role of RPLP2 in DLBCL, uncovers an unrecognized regulatory axis of ferroptosis, and identifies a specific inhibitor targeting RPLP2 to restrain DLBCL progression, suggesting that RPLP2 could be a potential target for DLBCL treatment. Full article

Frataxin is a component of the iron–sulfur (Fe-S) cluster assembly complex in mitochondria, and deficiency is associated with Friedreich ataxia (FA). The yeast homolog Yfh1 resembles and cross-complements with its human equivalent, and frataxin bypass scenarios are of particular interest because they may point to strategies for treating FA. Here, we describe frataxin/Yfh1 bypass by overexpression of Rsm22, an assembly factor for the mitochondrial ribosome. Rsm22 overexpression in Yfh1-depleted yeast cells restored critical processes in mitochondria, including Fe-S cluster assembly, lipoic acid synthesis, iron homeostasis, and heme synthesis, to a significant extent. Formation of cytoplasmic Fe-S proteins was also restored, suggesting recovery of the mitochondrial ability to generate the (Fe-S)_int intermediate that is exported from mitochondria and is utilized for cytoplasmic Fe-S cluster assembly. Importantly, an essential component of the mitochondrial iron–sulfur cluster machinery, namely ferredoxin, was virtually absent in mitochondria lacking Yfh1, but it was recovered with Rsm22 overexpression. Interestingly, ferredoxin overexpression could offset some of the effects of Yfh1 depletion. Ferredoxin has recently been shown to bind to the cysteine desulfurase protein Nfs1 at the same site as Yfh1, in a conserved arginine patch on Nfs1, such that ferredoxin binding at this site may confer frataxin-bypass activity. Full article

Friedreich’s ataxia (FRDA) results from a faulty mitochondrial protein known as Frataxin. The purpose of this case report was to test whether skeletal muscle in FRDA can adapt to an endurance-based training program using neuromuscular electrical stimulation (NMES). A 36-year-old female with FRDA completed twelve training sessions, each lasting 30 min over 30 days, focused on the forearm muscles using NMES. Pre- and post-training session measurements of contractions, muscle-specific endurance, and muscle mitochondrial capacity were taken per training session. Training contractions increased from 4200 to 9420. Muscle-specific endurance increased by 14% at 2 Hz and 17% at 4 Hz. Muscle endurance at 6 Hz increased from 0% to 51%. The rate constant of mitochondrial capacity was 0.95 min⁻¹ pre- and 0.99 min⁻¹ post-training session. In conclusion, one month of NMES increased training volume and muscle-specific endurance but did not change mitochondrial capacity. Muscle adaptations to endurance training were seen in FRDA, but increased training might be needed to test if mitochondrial capacity can improve. Full article

Friedreich ataxia (FRDA) is the most common inherited ataxia, primarily impacting the nervous system and the heart. It is characterized by GAA repeat expansion in the FXN gene, leading to reduced mitochondrial frataxin levels. Previously, we described a family displaying two expanded GAA alleles, not only in the proband affected by late-onset FRDA but also in the younger asymptomatic sister. The molecular characterization of the expanded repeats showed that the affected sister carried two canonical uninterrupted GAA expended repeats, whereas the asymptomatic sister had a compound heterozygous for a canonical GAA repeat and an expanded GAAGGA motif. Therefore, we decided to perform RNA sequencing (RNA-seq) on fibroblasts from both sisters in order to understand whether some genes and/or pathways might be differently involved in the occurrence of FRDA clinical manifestation. The transcriptomic analysis revealed 398 differentially expressed genes. Notably, TLR4, IL20RB, and SLITRK5 were up-regulated, while TCF21 and GRIN2A were down-regulated, as validated by qRT-PCR. Gene ontology (GO) enrichment and network analysis highlighted significant involvement in immune response and neuronal functions. Our results, in particular, suggest that TLR4 may contribute to inflammation in FRDA, while IL20RB, SLITRK5, TCF21, and GRIN2A dysregulation may play roles in the disease pathogenesis. This study introduces new perspectives on the inflammatory and developmental aspects in FRDA, offering potential targets for therapeutic intervention. Full article

Friedreich Ataxia (FRDA) is an inherited neuromuscular disorder triggered by a deficit of the mitochondrial protein frataxin. At a cellular level, frataxin deficiency results in insufficient iron–sulfur cluster biosynthesis and impaired mitochondrial function and adenosine triphosphate production. The main clinical manifestation is a progressive balance and coordination disorder which depends on the involvement of peripheral and central sensory pathways as well as of the cerebellum. Besides the neurological involvement, FRDA affects also the striated muscles. The most prominent manifestation is a hypertrophic cardiomyopathy, which also represents the major determinant of premature mortality. Moreover, FRDA displays skeletal muscle involvement, which contributes to the weakness and marked fatigue evident throughout the course of the disease. Herein, we review skeletal muscle findings in FRDA generated by functional imaging, histology, as well as multiomics techniques in both disease models and in patients. Altogether, these findings corroborate a disease phenotype in skeletal muscle and support the notion of progressive mitochondrial damage as a driver of disease progression in FRDA. Furthermore, we highlight the relevance of skeletal muscle investigations in the development of biomarkers for early-phase trials and future therapeutic strategies in FRDA. Full article

Background: Diabetic peripheral neuropathy (DPN) is considered one of the most common chronic complications of diabetes. Impairment of mitochondrial function is regarded as one of the causes. Iron–sulfur clusters are essential cofactors for numerous iron–sulfur (Fe-S)-containing proteins/enzymes, including mitochondrial electron transport chain complex I, II, and III and aconitase. Methods: To determine the impact of hyperglycemia on peripheral nerves, we used Schwann-like RSC96 cells and classical db/db mice to detect the expression of Fe-S-related proteins, mitochondrially enzymatic activities, and iron metabolism. Subsequently, we treated high-glucose-induced RSC96 cells and db/db mice with pioglitazone (PGZ), respectively, to evaluate the effects on Fe-S cluster biogenesis, mitochondrial function, and animal behavior. Results: We found that the core components of Fe-S biogenesis machinery, such as frataxin (Fxn) and scaffold protein IscU, significantly decreased in high-glucose-induced RSC96 cells and db/db mice, accompanied by compromised mitochondrial Fe-S-containing enzymatic activities, such as complex I and II and aconitase. Consequently, oxidative stress and inflammation increased. PGZ not only has antidiabetic effects but also increases the expression of Fxn and IscU to enhance mitochondrial function in RSC96 cells and db/db mice. Meanwhile, PGZ significantly alleviated sciatic nerve injury and improved peripheral neuronal behavior, accompanied by suppressed oxidative stress and inflammation in the sciatic nerve of the db/db mice. Conclusions: Iron–sulfur cluster deficiency may contribute to hyperglycemia-mediated DPN. Full article

Background: A drug repositioning effort supported the possible use of the anti-HIV drug etravirine as a disease-modifying drug for Friedreich ataxia (FRDA). Etravirine increases frataxin protein and corrects the biochemical defects in cells derived from FRDA patients. Because of these findings, and since etravirine displays a favorable safety profile, we conducted a pilot open-label phase 2 clinical trial assessing the safety and potential efficacy of etravirine in FRDA patients. Methods: Thirty-five patients were stratified into three severity groups and randomized to etravirine 200 mg/day or 400 mg/day. They were treated for 4 months. Safety endpoints were the number and type of adverse events and number of dropouts. Efficacy endpoints were represented by changes in peak oxygen uptake and workload as measured by incremental exercise test, SARA score, cardiac measures, measures of QoL and disability. Data were collected 4 months before the start of the treatment (T − 4), at the start (T0), at the end (T4) and 4 months after the termination of the treatment (T + 4). Results: Etravirine was reasonably tolerated, and adverse events were generally mild. Four months of etravirine treatment did not significantly increase the peak oxygen uptake but was associated with a change in the progression of the SARA score (p value < 0.001), compared to the 4 months pre- and post-treatment. It also significantly increased peak workload (p value = 0.021). No changes in the cardiac measures were observed. Health and QoL measures showed a worsening at the suspension of the drug. Conclusions: In this open trial etravirine treatment was safe, reasonably well tolerated and appreciably improved neurological function and exercise performance. Even though a placebo effect cannot be ruled out, these results suggest that etravirine may represent a potential therapeutic agent in FRDA deserving testing in a randomized placebo-controlled clinical trial. Full article

Trinucleotide repeat (TNR) expansion is the cause of over 40 neurodegenerative diseases, including Huntington’s disease and Friedreich’s ataxia (FRDA). There are no effective treatments for these diseases due to the poor understanding of molecular mechanisms underlying somatic TNR expansion and contraction in neural systems. We and others have found that DNA base excision repair (BER) actively modulates TNR instability, shedding light on the development of effective treatments for the diseases by contracting expanded repeats through DNA repair. In this study, temozolomide (TMZ) was employed as a model DNA base damaging agent to reveal the mechanisms of the BER pathway in modulating GAA repeat instability at the frataxin (FXN) gene in FRDA neural cells and transgenic mouse mice. We found that TMZ induced large GAA repeat contraction in FRDA mouse brain tissue, neurons, and FRDA iPSC-differentiated neural cells, increasing frataxin protein levels in FRDA mouse brain and neural cells. Surprisingly, we found that TMZ could also inhibit H3K9 methyltransferases, leading to open chromatin and increasing ssDNA breaks and recruitment of the key BER enzyme, pol β, on the repeats in FRDA neural cells. We further demonstrated that the H3K9 methyltransferase inhibitor BIX01294 also induced the contraction of the expanded repeats and increased frataxin protein in FRDA neural cells by opening the chromatin and increasing the endogenous ssDNA breaks and recruitment of pol β on the repeats. Our study provides new mechanistic insight illustrating that inhibition of H3K9 methylation can crosstalk with BER to induce GAA repeat contraction in FRDA. Our results will open a new avenue for developing novel gene therapy by targeting histone methylation and the BER pathway for repeat expansion diseases. Full article