Wednesday, January 8, 2020

Multiple mechanisms underpin cerebral and cerebellar white matter deficits in Friedreich ataxia: The IMAGE‐FRDA study

Louisa P. Selvadurai Louise A. Corben Martin B. Delatycki Elsdon Storey Gary F. Egan Nellie Georgiou‐Karistianis Ian H. Harding. Hum Brain Mapp. 2020; 1– 14. doi:10.1002/hbm.24921

For the first time, we examined the relative sensitivity and relationship between multiple white matter indices in Friedreich ataxia to more richly characterize disease expression and infer possible mechanisms underlying the observed white matter abnormalities.
Multiple mechanisms likely underpin white matter abnormalities in Friedreich ataxia, with differential impacts in cerebellar and cerebral pathways.

Tuesday, January 7, 2020

Heart-In-A-Jar Platform Humanizing Preclinical Research

Bio-IT World.By Deborah Borfitz, January 6, 2020.
The pumping capability was one of the more compelling features of the three-dimensional (3-D) organ construct for AstraZeneca, which is looking to screen drug candidates for treating heart failure with preserved ejection fraction—a common condition especially among the elderly and in women—with no effective therapy available, says Li. Novoheart’s cardiac tissue engineering technology, known as the MyHeart Platform, also held appeal for Pfizer, which has used it to model both electrical and mechanical defects of the heart in patients with the neurodegenerative disease Friedreich’s ataxia (FRDA).

In a study published earlier this year in Stem Cell Research & Therapy, the FRDA models demonstrated utility in evaluating novel therapeutics and disease progression. Study results highlighted the potential of small molecules or gene therapy for suppressing or reversing the cardiac symptoms of FRDA.

Monday, January 6, 2020

Researchers suggest a pathway to reverse the genetic defect of Friedreich's ataxia

Alexandra N. Khristich el al., "Large-scale contractions of Friedreich's ataxia GAA repeats in yeast occur during DNA replication due to their triplex-forming ability," PNAS (2019). Doi:10.1073/pnas.1913416117

"While these results were uncovered in a yeast model, they do provide us with a clue into the mechanism of DNA repeat instability in Friedreich's ataxia," said Alexandra Khristich, graduate student in Mirkin's lab and first author of the study. "I hope that our discovery would become a starting point for the potential development of therapeutic strategies that tip the balance toward DNA repeat contraction in patient tissues"

Friday, January 3, 2020

Longitudinal Increases in Cerebral Brain Activation During Working Memory Performance in Friedreich Ataxia: 24-Month Data from IMAGE-FRDA

Rosita Shishegar, Ian H. Harding, Louise A. Corben, Martin B. Delatycki, Elsdon Storey, Gary F. Egan, Nellie Georgiou-Karistianis; Cerebellum (2020). doi:10.1007/s12311-019-01094-6

These findings provide the first evidence of increased longitudinal activation over time in the cerebral cortex in FRDA, compared with controls, despite comparable working memory performance. This finding represents a possible compensatory response in the ventral attention network to help sustain working memory performance in individuals with FRDA.

Sunday, December 29, 2019

Health related quality of life in Friedreich Ataxia in a large heterogeneous cohort

Emily Xiong, Abigail E. Lynch, Louise A. Corben, Martin B. Delatycki, S.H. Subramony, Khalaf Bushara, Christopher M. Gomez, J. Chad Hoyle, Grace Yoon, Bernard Ravina, Katherine D. Mathews, George Wilmot, Theresa Zesiewicz, M. Susan Perlman, Jennifer M. Farmer, Christian Rummey, David R. Lynch; Neurological Sciences, Volume 0, Issue 0, 116642 DOI:10.1016/j.jns.2019.116642

The SF-36 and symptom specific scales capture dysfunction in FRDA in a manner that reflects disease status. HRQOL dysfunction was greatest on physically related scales; such scales correlated with disease duration, indicating that they worsen with progressing disease.

Friday, December 27, 2019

Exenatide induces frataxin expression and improves mitochondrial function in Friedreich ataxia

Mariana Igoillo-Esteve, Ana F. Oliveira, Cristina Cosentino, Federica Fantuzzi, Céline Demarez, Sanna Toivonen, Amélie Hu, Satyan Chintawar, Miguel Lopes, Nathalie Pachera, Ying Cai, Baroj Abdulkarim, Myriam Rai, Lorella Marselli, Piero Marchetti, Mohammad Tariq, Jean-Christophe Jonas, Marina Boscolo, Massimo Pandolfo, Décio L. Eizirik, and Miriam Cnop; JCI Insight. Published December 26, 2019. doi:10.1172/jci.insight.134221.
graphical abstract


Thursday, December 26, 2019

Antioxidant-mediated protective role of Hericium erinaceus (Bull.: Fr.) Pers. against oxidative damage in fibroblasts from Friedreich’s ataxia patient

LEW, Sze-Yuen; YOW, Yoon-Yen; LIM, Lee-Wei; WONG, Kah-Hui; SciELO journals. Dataset doi:10.6084/m9.figshare.11390835.v1

In this study, we investigated the antioxidant activities of a standardized aqueous extract from fruiting bodies of Hericium erinaceus mushroom (HESAE) and its protective effects against oxidative damage induced by L-Buthionine sulfoximine (BSO) in fibroblasts derived from FRDA patient. The lactate dehydrogenase-based viability assay showed that FRDA fibroblast was sensitive to 12.5 mM BSO with a reduction of viability to 52.51 ± 13.92% after 24 h of BSO exposure. Interestingly, co-incubation with 32 mg/mL HESAE increased the viability to 85.35 ± 3.4%. Further, 12.5 mM BSO caused a decrease in the ratio of cellular reduced glutathione (GSH) to oxidised GSH (GSSG) that leads to cell death.

FJ

Tuesday, December 24, 2019

Rating scales for rare neurological diseases

Massimo Pandolfo; Neurol Genet Dec 2019, 5 (6) e380; DOI: 10.1212/NXG.0000000000000380

While only future experience will establish whether these scales are equally effective in FRDA clinical trials or if one proves superior, the point that they are both ataxia rating scales rather than comprehensive assessments of all FRDA neurologic features remains. Can we generalize this conclusion and say that rating scales assessing specific neurologic features are to be preferred to disease-specific scales in rare neurologic disorders? This is an open and controversial question. There have been and there are continuing efforts to develop and validate disease-specific scales for rare and even ultra-rare diseases, with the goal of disposing of robust, sensitive outcome measures for clinical trials, capturing as much as possible of the complexities of each of these conditions. Whether the same goal can be attained by appropriately combining general scales for neurologic impairments as weakness, spasticity, ataxia, and dystonia remains to be determined, but, in the light of our experience with a disease with as complex a neurologic picture as FRDA, this approach may be a viable and possibly even a preferable option.

Monday, December 23, 2019

Nanoscopic X‐ray imaging and quantification of the iron cellular architecture within single fibroblasts of Friedreich's ataxia patients

De Samber, B., Vanden Berghe, T., Meul, E., Bauters, S., Seyrich, M., Smet, J., De Paepe, B., da Silva, J.C., Bohic, S., Cloetens, P., Van Coster, R., Vandenabeele, P. and Vincze, L. (2020), J. Synchrotron Rad.. doi:10.1107/S1600577519015510

Here the nanoscale iron distribution within single fibroblasts from FRDA patients was investigated using synchrotron‐radiation‐based nanoscopic X‐ray fluorescence and X‐ray in‐line holography at the ID16A nano‐imaging beamline of the ESRF.
Various micrometre‐sized iron‐rich organelles could be revealed for the first time, tentatively identified as endoplasmic reticulum, mitochondria and lysosomes. Also a multitude of nanoscopic iron hot‐spots were observed in the cytosol, interpreted as chaperoned iron within the fibroblast's labile iron pool. These observations enable new hypotheses on the storage and trafficking of iron in the cell and ultimately to a better understanding of iron‐storage diseases such as Friedreich's ataxia.


Sunday, December 22, 2019

Age of onset determines intrinsic functional brain architecture in Friedreich ataxia

Naeije, G., Wens, V., Coquelet, N., Sjøgård, M., Goldman, S., Pandolfo, M. and De Tiège, X.P. (2019). Ann Clin Transl Neurol. doi:10.1002/acn3.50966

Age of symptoms onset is a major determinant of FRDA patients' intrinsic functional brain architecture. Higher rsFC in FRDA patients with later age of symptoms onset supports compensatory mechanisms for FRDA‐related neural network dysfunction and position neuromagnetic rsFC as potential marker of FRDA neural reserve.