Format

Send to

Choose Destination
Neurobiol Dis. 2015 Sep;81:144-53. doi: 10.1016/j.nbd.2015.02.030. Epub 2015 Mar 30.

Mitochondrial iron and energetic dysfunction distinguish fibroblasts and induced neurons from pantothenate kinase-associated neurodegeneration patients.

Author information

1
San Raffaele Scientific Institute, Division of Neuroscience, 20132 Milano, Italy.
2
Molecular Neurogenetics Unit, Foundation IRCCS-Neurological Institute "Carlo Besta", 20126 Milano, Italy.
3
San Raffaele Scientific Institute, Division of Neuroscience, 20132 Milano, Italy; University Vita-Salute San Raffaele, 20132 Milano, Italy.
4
San Raffaele Scientific Institute, Division of Neuroscience, 20132 Milano, Italy; University Vita-Salute San Raffaele, 20132 Milano, Italy. Electronic address: levi.sonia@hsr.it.

Abstract

Pantothenate kinase-associated neurodegeneration is an early onset autosomal recessive movement disorder caused by mutation of the pantothenate kinase-2 gene, which encodes a mitochondrial enzyme involved in coenzyme A synthesis. The disorder is characterised by high iron levels in the brain, although the pathological mechanism leading to this accumulation is unknown. To address this question, we tested primary skin fibroblasts from three patients and three healthy subjects, as well as neurons induced by direct fibroblast reprogramming, for oxidative status, mitochondrial functionality and iron parameters. The patients' fibroblasts showed altered oxidative status, reduced antioxidant defence, and impaired cytosolic and mitochondrial aconitase activities compared to control cells. Mitochondrial iron homeostasis and functionality analysis of patient fibroblasts indicated increased labile iron pool content and reactive oxygen species development, altered mitochondrial shape, decreased membrane potential and reduced ATP levels. Furthermore, analysis of induced neurons, performed at a single cell level, confirmed some of the results obtained in fibroblasts, indicating an altered oxidative status and signs of mitochondrial dysfunction, possibly due to iron mishandling. Thus, for the first time, altered biological processes have been identified in vitro in live diseased neurons. Moreover, the obtained induced neurons can be considered a suitable human neuronal model for the identification of candidate therapeutic compounds for this disease.

KEYWORDS:

Induced neurons; Iron metabolism; Mitochondria; NBIA; PANK2; Reactive oxygen species

PMID:
25836419
PMCID:
PMC4642744
DOI:
10.1016/j.nbd.2015.02.030
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Elsevier Science Icon for PubMed Central
Loading ...
Support Center