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Laser microdissection-based microproteomics of the hippocampus of a rat epilepsy model reveals regional differences in protein abundances.

ABSTRACT: Mesial temporal lobe epilepsy (MTLE) is a chronic neurological disorder affecting almost 40% of adult patients with epilepsy. Hippocampal sclerosis (HS) is a common histopathological abnormality found in patients with MTLE. HS is characterised by extensive neuronal loss in different hippocampus sub-regions. In this study, we used laser microdissection-based microproteomics to determine the protein abundances in different regions and layers of the hippocampus dentate gyrus (DG) in an electric stimulation rodent model which displays classical HS damage similar to that found in patients with MTLE. Our results indicate that there are differences in the proteomic profiles of different layers (granule cell and molecular), as well as different regions, of the DG (ventral and dorsal). We have identified new signalling pathways and proteins present in specific layers and regions of the DG, such as PARK7, RACK1, and connexin 31/gap junction. We also found two major signalling pathways that are common to all layers and regions: inflammation and energy metabolism. Finally, our results highlight the utility of high-throughput microproteomics and spatial-limited isolation of tissues in the study of complex disorders to fully appreciate the large biological heterogeneity present in different cell populations within the central nervous system.

SUBMITTER: do Canto AM

PROVIDER: S-EPMC7064578 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Laser microdissection-based microproteomics of the hippocampus of a rat epilepsy model reveals regional differences in protein abundances.

do Canto Amanda M AM Vieira André S AS H B Matos Alexandre A Carvalho Benilton S BS Henning Barbara B Norwood Braxton A BA Bauer Sebastian S Rosenow Felix F Gilioli Rovilson R Cendes Fernando F Lopes-Cendes Iscia I

Scientific reports 20200310 1

Mesial temporal lobe epilepsy (MTLE) is a chronic neurological disorder affecting almost 40% of adult patients with epilepsy. Hippocampal sclerosis (HS) is a common histopathological abnormality found in patients with MTLE. HS is characterised by extensive neuronal loss in different hippocampus sub-regions. In this study, we used laser microdissection-based microproteomics to determine the protein abundances in different regions and layers of the hippocampus dentate gyrus (DG) in an electric sti ...[more]

PMID: 32157145

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Dataset Information

Laser microdissection-based microproteomics of the hippocampus of a rat epilepsy model reveals regional differences in protein abundances.

Publications

Laser microdissection-based microproteomics of the hippocampus of a rat epilepsy model reveals regional differences in protein abundances.

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