Heart failure & cardiomyopathiesResearch article
The Cardiac Calcium Handling Machinery is Remodeled in Friedreich’s Ataxia
- Human left ventricular tissue from friedreich's ataxia (FA) patients and unaffected donors, and an frataxin (FXN) knock-out (FXN knock-out (FXN-KO)) mouse model, were analyzed
Authors' conclusion
Cardiac dysfunction in FA is associated with impaired calcium handling, mitochondrial dysregulation, and systolic impairment, identifying potential molecular targets for therapy.
Study context
- Population
- FA patients and unaffected donors (human left ventricular tissue); FXN knock-out (FXN-KO) mouse model
- Comparison
- FA patients vs Unaffected donors vs FXN-KO mice
Main finding
As reported in the abstract
Cardiac function (echocardiography)
- FXN-KO mice exhibited significant reductions in ejection fraction, stroke volume, fractional shortening, and cardiac output, with increased LV mass and elevated end-diastolic and end-systolic volumes
Further findings
Strain analysis
- Increased global and peak longitudinal strain
ECG intervals
- RR, PR, QRS, and QTc intervals were prolonged
Calcium-handling proteins
- Both human FA and FXN-KO hearts showed downregulation of SERCA2a and Ryr2, with reduced phospholamban phosphorylation
Mitochondrial calcium handling and function
- FXN-KO mice showed upregulation of mitochondrial calcium-handling proteins, including MCU and VDAC, depolarized Δψm, and elevated reactive oxygen species (ROS)
Original publication
The Cardiac Calcium Handling Machinery is Remodeled in Friedreich’s Ataxia. Heart Rhythm. Published 5 October 2026. doi:10.1016/j.hrthm.2026.09.048
Summarised from the published abstract; every number is checked against it