Dataset Information

Mitochondrial proteomic analysis of a cell line model of familial amyotrophic lateral sclerosis.

ABSTRACT: Mutations in copper-zinc superoxide dismutase (SOD1) have been linked to a subset of familial amytrophic lateral sclerosis (fALS), a fatal neurodegenerative disease characterized by progressive motor neuron death. An increasing amount of evidence supports that mitochondrial dysfunction and apoptosis activation play a critical role in the fALS etiology, but little is known about the mechanisms by which SOD1 mutants cause the mitochondrial dysfunction and apoptosis. In this study, we use proteomic approaches to identify the mitochondrial proteins that are altered in the presence of a fALS-causing mutant G93A-SOD1. A comprehensive characterization of mitochondrial proteins from NSC34 cells, a motor neuron-like cell line, was achieved by two independent proteomic approaches. Four hundred seventy unique proteins were identified in the mitochondrial fraction collectively, 75 of which are newly discovered proteins that previously had only been reported at the cDNA level. Two-dimensional gel electrophoresis was subsequently used to analyze the differences between the mitochondrial proteomes of NSC34 cells expressing wild-type and G93A-SOD1. Nine and 36 protein spots displayed elevated and suppressed abundance respectively in G93A-SOD1-expressing cells. The 45 spots were identified by MS, and they include proteins involved in mitochondrial membrane transport, apoptosis, the respiratory chain, and molecular chaperones. In particular, alterations in the post-translational modifications of voltage-dependent anion channel 2 (VDAC2) were found, and its relevance to regulating mitochondrial membrane permeability and activation of apoptotic pathways is discussed. The potential role of other proteins in the mutant SOD1-mediated fALS is also discussed. This study has produced a short list of mitochondrial proteins that may hold the key to the mechanisms by which SOD1 mutants cause mitochondrial dysfunction and neuronal death. It has laid the foundation for further detailed functional studies to elucidate the role of particular mitochondrial proteins, such as VDAC2, in the pathogenesis of familial ALS.

SUBMITTER: Fukada K

PROVIDER: S-EPMC1360176 | biostudies-literature | 2004 Dec

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Mitochondrial proteomic analysis of a cell line model of familial amyotrophic lateral sclerosis.

Fukada Kei K Zhang Fujian F Vien Alexis A Cashman Neil R NR Zhu Haining H

Molecular & cellular proteomics : MCP 20041021 12

Mutations in copper-zinc superoxide dismutase (SOD1) have been linked to a subset of familial amytrophic lateral sclerosis (fALS), a fatal neurodegenerative disease characterized by progressive motor neuron death. An increasing amount of evidence supports that mitochondrial dysfunction and apoptosis activation play a critical role in the fALS etiology, but little is known about the mechanisms by which SOD1 mutants cause the mitochondrial dysfunction and apoptosis. In this study, we use proteomic ...[more]

PMID: 15501831

Similar Datasets

Project description:The present study used comparative proteomic analysis of cerebrospinal fluid (CSF) in amyotrophic lateral sclerosis (ALS) patients in order to identify proteins that may act as diagnostic biomarkers and indicators of the pathogenesis of ALS. This analysis was performed using isobaric tags for relative and absolute quantitation (iTRAQ) technology, coupled with 2-dimensional liquid chromatography/mass spectrometry. Database for Annotation, Visualization and Integrated Discovery software was utilized for bioinformatic analysis of the data. Following this, western blotting was performed in order to examine the expression of 3 candidate proteins in ALS patients compared with healthy individuals [as a normal control (NC) group] or patients with other neurological disease (OND); these proteins were insulin-like growth factor II (IGF-2), glutamate receptor 4 (GRIA4) and leucine-rich α-2-glycoprotein 1 (LRG1). Clinical data, including gender, age, disease duration and ALS functional rating scale (ALSFRS-R) score, were also collected in the ALS patients. Multiple linear regression analysis was performed between the clinical data and the results of western blot analysis. A total of 248 distinct proteins were identified in the ALS and NC groups, amongst which a significant difference could be identified in 35 proteins; of these, 21 proteins were downregulated and 14 were upregulated. These differentially-expressed proteins were thus revealed to be associated with ALS. The western blot analysis confirmed a proportion of the data attained in the iTRAQ analysis, revealing the differential protein expression of IGF-2 and GRIA4 between the ALS and NC groups. IGF-2 was significantly downregulated in ALS patients (P=0.017) and GRIA4 was significantly upregulated (P=0.016). These results were subsequently validated in the 35-patient ALS and OND groups (P=0.002), but no significant difference was identified in LRG1 expression between these groups. GRIA4 protein expression was higher in male than female patients and was positively correlated with the ALSFRS-R score, meaning that GRIA4 expression was negatively correlated with the severity of ALS, while IGF-2 and LRG1 expression did not correlate with any clinical data. The present study thus demonstrated that GRIA4 expression levels, as a marker of severity, may be used as a reference for the timing of treatment, and that IGF-2 may serve as an effective biomarker of ALS progression.

Project description:BACKGROUND:It is unclear to what extent pre-clinical studies in genetically homogeneous animal models of amyotrophic lateral sclerosis (ALS), an invariably fatal neurodegenerative disorder, can be informative of human pathology. The disease modifying effects in animal models of most therapeutic compounds have not been reproduced in patients. To advance therapeutics in ALS, we need easily accessible disease biomarkers which can discriminate across the phenotypic variants observed in ALS patients and can bridge animal and human pathology. Peripheral blood mononuclear cells alterations reflect the rate of progression of the disease representing an ideal biological substrate for biomarkers discovery. METHODS:We have applied TMTcalibrator™, a novel tissue-enhanced bio fluid mass spectrometry technique, to study the plasma proteome in ALS, using peripheral blood mononuclear cells as tissue calibrator. We have tested slow and fast progressing SOD1G93A mouse models of ALS at a pre-symptomatic and symptomatic stage in parallel with fast and slow progressing ALS patients at an early and late stage of the disease. Immunoassays were used to retest the expression of relevant protein candidates. RESULTS:The biological features differentiating fast from slow progressing mouse model plasma proteomes were different from those identified in human pathology, with only processes encompassing membrane trafficking with translocation of GLUT4, innate immunity, acute phase response and cytoskeleton organization showing enrichment in both species. Biological processes associated with senescence, RNA processing, cell stress and metabolism, major histocompatibility complex-II linked immune-reactivity and apoptosis (early stage) were enriched specifically in fast progressing ALS patients. Immunodetection confirmed regulation of the immunosenescence markers Galectin-3, Integrin beta 3 and Transforming growth factor beta-1 in plasma from pre-symptomatic and symptomatic transgenic animals while Apolipoprotein E differential plasma expression provided a good separation between fast and slow progressing ALS patients. CONCLUSIONS:These findings implicate immunosenescence and metabolism as novel targets for biomarkers and therapeutic discovery and suggest immunomodulation as an early intervention. The variance observed in the plasma proteomes may depend on different biological patterns of disease progression in human and animal model.

Project description:Extracellular vesicles (EVs) hold the potential for elucidating the pathogenesis and serving as biomarkers of amyotrophic lateral sclerosis (ALS). Notably, the comparative and longitudinal alterations in the protein profiles of EVs in serum (sEVs) and CSF (cEVs) of sporadic ALS (SALS) patients remain unexplored. This study sought to reveal such changes by collecting serum and CSF at fixed intervals from 10 controls and 20 SALS patients participating in the Ropinirole Hydrochloride Remedy for Amyotrophic Lateral Sclerosis trial. We also aimed to reveal longitudinal changes with disease progression and the effects of ropinirole hydrochloride (ROPI, a dopamine D2 receptor agonist identified as an anti-ALS drug candidate using induced pluripotent stem cell drug discovery) on protein profiles of EVs. Comprehensive proteomic analyses of EVs extracted from these samples were conducted using liquid chromatography-mass spectrometry to trace longitudinal shifts linked to disease progression and the influence of ROPI on EV protein profiles. The findings revealed notable disparities but high congruity in sEV and cEV protein profiles concerning disease status, time, and ROPI administration. Moreover, the sEV and cEV protein profiles converged over time in SALS patients, at least in part, suggestive of a loosening of the blood–brain barrier. In SALS patients, both sEVs and cEVs presented elevated inflammation-related protein levels but reduced levels of proteins associated with the unfolded protein response. These results mirrored the longitudinal changes after disease onset and correlated with the revised ALS Functional Rating Scale at sampling time, suggesting a link to the onset and progression of SALS. ROPI appeared to counteract these changes, attenuating inflammation-related protein levels and boosting those tied to the unfolded protein response in SALS, suggesting an anti-ALS effect on EV protein profiles. Reverse translational research using induced pluripotent stem cell-derived astrocytes indicated that these changes may partly reflect the DRD2-dependent neuroinflammatory inhibitory effects of ROPI. Baseline levels of OGN in sEVs and FRMPD1 in cEVs correlated with subsequent disease progression, indicating their potential as prognostic biomarkers for SALS. Machine learning-driven biomarker searches and diagnostic classification yielded an accuracy of 90.4% for sEVs and 80.3% for cEVs. Despite the limited sample size, this study is the first to report time-series proteomic alterations in sEVs and cEVs from SALS patients, offering comprehensive insights into SALS pathogenesis, ROPI-induced changes, and potential prognostic and diagnostic biomarkers.

Dataset Information

Mitochondrial proteomic analysis of a cell line model of familial amyotrophic lateral sclerosis.

Publications

Mitochondrial proteomic analysis of a cell line model of familial amyotrophic lateral sclerosis.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets