Dataset Information

Protein profiling and identification of new biomarkers of brain ischemia by MALDI-imaging-mass-spectrometry

ABSTRACT: Introduction The identification of proteins involved in brain ischemia might allow the discovery of new putative biomarkers or potential therapeutic target of one of the most important neurological disorders. MALDI Imaging-Mass-Spectrometry (IMS) is a powerful technique that allows the visualization of protein distribution along a tissue without labeling. Our aim is to study the distribution of proteins along mouse brain after an ischemic insult and to identify relevant proteins involved in brain ischemia. Materials and methods We occluded the middle cerebral artery (60min) of C57BL/6J mice (n=4) with 24h of reperfusion. Brain slices were analyzed by MALDI-TOF and mass spectra from infarct (IC) and contralateral (CL) regions were compared using ClinProTools. Relevant m/z were selected after PCA analysis and their ion distribution maps were analyzed by FlexImagin3.0. Protein identification was conducted on mouse brain homogenates through a bottom-up approach consisting on complementary fractionations based on tricine gels and RP-HPLC. The identifications were confirmed by immunohistochemistry. Results We identified 102 m/z with different abundances between IC and CL (p<0.05), from which 21 m/z were selected by PCA as more relevant. Thirteen of them were found increased in the infarct region and 4 m/z showed a discrimination higher than 90% between IC and CL. After bottom-up identification, immunohistochemistry analysis confirmed increased ATP5i and COX6C expressions, and decreased UMP-CMP kinase in IC compared to CL. Conclusions We identified for the first time by MALDI-IMS several m/z peaks with different abundances between IC and CL. These proteins involved in brain ischemia might represent potential diagnostic biomarkers or target molecules for neurological recovery.

INSTRUMENT(S): LTQ Orbitrap Velos

ORGANISM(S): Mus Musculus (mouse)

TISSUE(S): Brain

SUBMITTER: Víctor Llombart

LAB HEAD: Joan Montaner

PROVIDER: PXD003644 | Pride | 2016-12-14

REPOSITORIES: Pride

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Dataset's files

Source:

			Action	DRS
	02262015_VLL_MALDI_7_45min.raw	Raw
	02262015_VLL_MALDI_8_45min.raw	Raw
	02262015_VLL_MALDI_9_45min.raw	Raw
	11142014_CL1_45min.raw	Raw
	11142014_CL2_45min.raw	Raw

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Profiling and identification of new proteins involved in brain ischemia using MALDI-imaging-mass-spectrometry.

Llombart Víctor V Trejo Sebastián Alejandro SA Bronsoms Sílvia S Morancho Anna A Feifei Ma M Faura Júlia J García-Berrocoso Teresa T Simats Alba A Rosell Anna A Canals Francesc F Hernández-Guillamón Mar M Montaner Joan J

Journal of proteomics 20161122

The identification of proteins involved in brain ischemia might allow the discovery of putative biomarkers or therapeutic targets for ischemic stroke. Our aim is to study the distribution of proteins within mouse brain after an ischemic insult using MALDI imaging-mass-spectrometry and to identify relevant proteins involved in brain damage. We occluded the middle cerebral artery of C57BL/6J mice. Brain slices were analyzed by MALDI-TOF and infarct (IC) and contralateral (CL) regions were compared ...[more]

PMID: 27888142

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