Dados do Trabalho

Título

Proteomic analysis of synaptosomes isolated from brain tissue of patients with mesial temporal lobe epilepsy

Resumo

Introduction: The synapses are electric, and chemical communications between the neurons and synaptosomes are membrane vesicles that contain the synaptic components. The study of synaptosomes can give clues about synaptic transmission and its abnormalities since they contain all the machinery involved in the release, reuptake, and storage of neurotransmitters. In addition, synaptic proteins are possible therapeutic targets in many neurological diseases.
Mesial temporal lobe epilepsy (MTLE) is the most common type of focal epilepsy in adults. It presents a high proportion of patients who do not respond to antiseizure medication (ASM) treatment. However, patients with MTLE who are pharmacoresistant to treatment with ASM may benefit from epilepsy surgery.
Objective: To characterize the protein content of synaptosomes isolated from tissue of patients with pharmacoresistant MTLE using mass spectrometry-based proteomics
Methods: We analyzed the synaptosomes isolated from brain tissue obtained from epilepsy surgery (hippocampus and temporal lobe) of patients with MTLE and compared it to normal tissue. We isolated the synaptosomes using the Syn-PER reagent, extracted and digested the proteins using the S-Trap columns, and labeled them with TMT11-plex. Data was acquired using a Thermo ScientificTM Orbitrap EclipseTM TribridTM coupled to a Dionex UPLC system. We used the ProteomeDiscoverer and R software for bioinformatics analysis.
Results: We identified 1,890 proteins, 7,521 peptides and 18,601 PSMs. Our foldchange (FC) analysis revealed some critical proteins that may be relevant in the epilepsy context. Some of them are Synapsin-3 (FC=104), Abl interactor 1 (FC=147), Sodium-driven chloride bicarbonate exchanger (FC=37.8), and Outer mitochondrial transmembrane helix translocase (FC=51). The expression of these proteins was higher in the tissue of patients when compared to controls.
Conclusion: Our study explores for the first time the synaptosome proteome of patients with MTLE. We identified novel proteins that may have a role in disease mechanisms, or they may contribute to biological processes leading to pharmacoresistance in MTLE.

Palavras Chave

mesial temporal lobe epilepsy; proteomics; hippocampus