A peptide derived from TID1S rescues frataxin deficiency and mitochondrial defects in FRDA cellular models

Yi Na Dong, Lucie V. Ngaba, Jacob An, Miniat W. Adeshina, Nathan Warren, Jonathan Wong, David R. Lync, Front. Pharmacol. Sec. Neuropharmacology, Volume 15 - 2024, doi: 10.3389/fphar.2024.1352311  

The study of frataxin protein regulation might yield new approaches for FRDA treatment. Here, we report tumorous imaginal disc 1 (TID1), a mitochondrial J-protein cochaperone, as a binding partner of frataxin that negatively controls frataxin protein levels. TID1 interacts with frataxin both in vivo in mouse cortex and in vitro in cortical neurons. Acute and subacute depletion of frataxin using RNA interference markedly increases TID1 protein levels in multiple cell types. In addition, TID1 overexpression significantly increases frataxin precursor but decreases intermediate and mature frataxin levels in HEK293 cells. In primary cultured human skin fibroblasts, overexpression of TID1S results in decreased levels of mature frataxin and increased fragmentation of mitochondria. This effect is mediated by the last 6 amino acids of TID1S as a peptide made from this sequence rescues frataxin deficiency and mitochondrial defects in FRDA patient-derived cells. Our findings show that TID1 negatively modulates frataxin levels, and thereby suggests a novel therapeutic target for treating FRDA.

Nerve Ultrasound in Friedreich’s Ataxia: enlarged nerves as a Biomarker of disease severity

G. Di Pietro, E. Cioffi, P. Falco, E. Galosi, G. De Stefano, G. Di Stefano, C. Leone, V. Martines, S. Perotti, C. Casali, A. Truini, Nerve Ultrasound in Friedreich’s Ataxia: enlarged nerves as a Biomarker of disease severity, Clinical Neurophysiology, 2024, ISSN 1388-2457, doi:10.1016/j.clinph.2024.01.004 

 Our study now shows that high-resolution nerve ultrasound examination can detect nerve enlargements in patients with Friedreich's ataxia (mostly at the level of upper limbs). Neve ultrasound abnormalities correlate with clinically established variables in patients with Friedreich's ataxia. This technique, therefore, might be a promising biomarker for measuring disease severity and treatment effects in this rare and severely disabling condition.