Analytical Method and Stability Study for Oral Suspension of Idebenone in Syrspend

Porru, E.; Piro, F.; Comito, R.; Mosendz, A.; Minniti, E.; Conti, M.; Stancari, A.; Violante, F.S. Analytical Method and Stability Study for Oral Suspension of Idebenone in Syrspend. Separations 2023, 10, 517. doi:10.3390/separations10090517 

The greatest disadvantage of IDB is its low solubility in water, resulting in low bioavailability. Galenic preparations of IDB in customized doses are common for pediatric patients, which can often prove to be the only option for access to therapy. As an antioxidant, the chemical stability of IDB is an essential guarantee for exerting the desired antioxidant action. Stability studies are essential to know the effect of storage conditions of a galenic product. For the first time, a stability-indicating LC-MS method has been developed to define the stability of IDB suspensions in SyrSpend® Sugar-Free Unflavored (Fagron), a carrier phase formulated for setting up suspensions of active pharmaceutical ingredients (APIs) insoluble or poorly insoluble in water and compatible with it.

Patient-derived iPSC models of Friedreich ataxia: a new frontier for understanding disease mechanisms and therapeutic application

Maheshwari S, Vilema-Enríquez G, Wade-Martins R. Patient-derived iPSC models of Friedreich ataxia: a new frontier for understanding disease mechanisms and therapeutic application. Transl Neurodegener. 2023 Sep 20;12(1):45. doi: 10.1186/s40035-023-00376-8. PMID: 37726850. 

These models enable studies of the molecular mechanisms underlying GAA-induced pathology, as well as providing an exciting tool for the screening and testing of novel disease-modifying therapies. This review explores how the use of iPSCs to study FRDA has developed over the past decade, as well as discussing the enormous therapeutic potentials of iPSC-derived models, their current limitations and their future direction within the field of FRDA research.

Butyrate prevents visceral adipose tissue inflammation and metabolic alterations in a Friedreich’s ataxia mouse model

Turchi R, Sciarretta F, Ceci V, Tiberi M, Audano M, Pedretti S, Panebianco C, Nesci V, Pazienza V, Ferri A, Carotti S, Chiurchiù V, Mitro N, Lettieri-Barbato D, Aquilano K. Butyrate prevents visceral adipose tissue inflammation and metabolic alterations in a Friedreich's ataxia mouse model. iScience. 2023 Aug 28;26(10):107713. doi: 10.1016/j.isci.2023.107713. PMID: 37701569; PMCID: PMC10494209.  

Metagenomic analysis indicated a reduction in fecal butyrate-producing bacteria, known to exert antidiabetic effects. A butyrate-enriched diet restrained vWAT abnormalities and mitigated diabetes features in KIKO mice. Our work emphasizes the role of vWAT in FA-related metabolic issues and suggests butyrate as a safe and promising adjunct for FA management.

Neurologic orphan diseases: Emerging innovations and role for genetic treatments

Kioutchoukova IP, Foster DT, Thakkar RN, Foreman MA, Burgess BJ, Toms RM, Molina Valero EE, Lucke-Wold B. Neurologic orphan diseases: Emerging innovations and role for genetic treatments. World J Exp Med 2023; 13(4): 59-74 [DOI: 10.5493/wjem.v13.i4.59]. 

 Neurologic orphan diseases are rare conditions that impact a small percentage of the population. Through new advances in technology and research, the use of genetic treatment for these conditions is increasing. Recent advances in clustered regularly interspaced palindromic repeats/Cas9, adeno-associated viral vectors, antisense oligonucleotides, and mammalian target of rapamycin inhibitors have shown improvements in the care of patients and their quality of life.

SIRT3 Regulates Clearance of Apoptotic Cardiomyocytes by Deacetylating Frataxin

Jing Gao, Chenglin Huang, Linghui Kong, Wugang Zhou, Mengwei Sun, Tong Wei and Weili Shen; SIRT3 Regulates Clearance of Apoptotic Cardiomyocytes by Deacetylating Frataxin. Circulation ResearchVolume 133, Issue 7, 15 September 2023; Pages 631-647 doi:1161/CIRCRESAHA.123.323160  

The SIRT3-FXN axis has the potential to resolve cardiac inflammation by increasing macrophage efferocytosis and anti-inflammatory activities.

Friedreich's ataxia: new insights

Krasilnikova MM, Humphries CL, Shinsky EM. Friedreich's ataxia: new insights. Emerg Top Life Sci. 2023 Sep 12:ETLS20230017. doi: 10.1042/ETLS20230017. Epub ahead of print. PMID: 37698160. 

 Friedreich ataxia (FRDA) is an inherited disease that is typically caused by GAA repeat expansion within the first intron of the FXN gene coding for frataxin. This results in the frataxin deficiency that affects mostly muscle, nervous, and cardiovascular systems with progressive worsening of the symptoms over the years. This review summarizes recent progress that was achieved in understanding of molecular mechanism of the disease over the last few years and latest treatment strategies focused on overcoming the frataxin deficiency.

Comparative multi-omics analyses of cardiac mitochondrial stress in three mouse models of frataxin deficiency

Nicole M. Sayles, Jill S. Napierala, Josef Anrather, Nadège Diedhiou, Jixue Li, Marek Napierala, Hélène Puccio, Giovanni Manfredi; Comparative multi-omics analyses of cardiac mitochondrial stress in three mouse models of frataxin deficiency. Dis Model Mech 2023; dmm.050114. doi: doi:10.1242/dmm.050114

Transcriptional changes were found in all models, but differentially expressed genes consistent with cardiomyopathy and ISRmt were only identified in FxnG127V hearts. However, these changes were surprisingly mild even at an advanced age (18-months), despite a severe decrease in FXN levels to 1% of WT. These findings indicate that the mouse heart has low reliance on FXN, highlighting the difficulty in modeling genetically relevant FA cardiomyopathy.

Propensity matched comparison of omaveloxolone treatment to Friedreich ataxia natural history data

Lynch, D.R., Goldsberry, A., Rummey, C., Farmer, J., Boesch, S., Delatycki, M.B., Giunti, P., Hoyle, J.C., Mariotti, C., Mathews, K.D., Nachbauer, W., Perlman, S., Subramony, S.H., Wilmot, G., Zesiewicz, T., Weissfeld, L. and Meyer, C. (2023), Propensity matched comparison of omaveloxolone treatment to Friedreich ataxia natural history data. Ann Clin Transl Neurol. doi:10.1002/acn3.51897 

These results suggest a meaningful slowing of Friedreich ataxia progression with omaveloxolone, and consequently detail how propensity-matched analysis may contribute to understanding of effects of therapeutic agents. This demonstrates the direct value of natural history studies in clinical trial evaluations.

Proprioceptive and tactile processing in individuals with Friedreich Ataxia, an fMRI study

Destrebecq Virginie, Rovai Antonin, Trotta Nicola, Comet Camille, Gilles Naeije, Front. Neurol. Sec. Movement Disorders, Volume 14 - 2023, doi: 10.3389/fneur.2023.1224345

Our study captured the difference between tactile and proprioceptive impairments in FA using somatosensory fMRI paradigms. The lack of correlation between the proprioceptive paradigm and ataxia clinical parameters supports a low contribution of afferent ataxia to FA clinical severity

SIRT3 Regulates Clearance of Apoptotic Cardiomyocytes by Deacetylating Frataxin

Jing Gao, Chenglin Huang, Linghui Kong, Wugang Zhou, Mengwei Sun, Tong Wei and Weili Shen. Circulation Research. 2023;0. Originally published 30 Aug 2023 doi:10.1161/CIRCRESAHA.123.323160  

We showed that SIRT3 deficiency exacerbated Ang II–induced downregulation of the efferocytosis receptor MerTK (c-Mer tyrosine kinase) and proinflammatory cytokine production, accompanied by disrupted mitochondrial iron homeostasis in cardiac macrophages. Quantitative acetylome analysis revealed that SIRT3 deacetylated FXN (frataxin) at lysine 189. Ang II attenuated SIRT3 activity and enhanced the acetylation level of FXN K189. Acetylated FXN further reduced the synthesis of ISCs (iron-sulfur clusters), resulting in mitochondrial iron accumulation. Phagocytic internalization of apoptotic cardiomyocytes increased myoglobin content, and derived iron ions promoted mitochondrial iron overload and lipid peroxidation. An iron chelator deferoxamine improved the levels of MerTK and efferocytosis, thereby attenuating proinflammatory macrophage activation. FXNK189R mice showed improved macrophage efferocytosis, reduced cardiac inflammation, and suppressed cardiac fibrosis.