The proteomic signature of circulating extracellular vesicles following intracerebral hemorrhage: Novel insights into mechanisms underlying recovery.

Circulating extracellular vesicles (EVs) can participate in innate repair processes triggered after intracerebral hemorrhage (ICH). We aimed to describe changes in the proteomic profile of circulating EVs between the acute and subacute phases of ICH and to compare the findings depending on outcomes, as an approach to unraveling such repair mechanisms. This was a prospective observational study including patients with non-traumatic supratentorial ICH.

The impact of experimental diabetes on intracerebral haemorrhage. A preclinical study.

Although diabetes mellitus negatively affects post-ischaemic stroke injury and recovery, its impact on intracerebral haemorrhage (ICH) remains uncertain. This study aimed to investigate the effect of experimental diabetes (ED) on ICH-induced injury and neurological impairment. Sprague-Dawley rats were induced with ED 2 weeks before ICH induction.

Dual role of peripheral B cells in multiple sclerosis: emerging remote players in demyelination and novel diagnostic biomarkers.

Introduction: Multiple sclerosis is an inflammatory and demyelinating disease caused by a pathogenic immune response against the myelin sheath surfaces of oligodendrocytes. The demyelination has been classically associated with pathogenic B cells residing in the central nervous system that release autoreactive antibodies against myelin. The aim of the present study was to investigate whether extracellular vesicles (EVs) mediate delivery of myelin autoreactive antibodies from peripheral B cells against oligodendrocytes in multiple sclerosis (MS) and to analyze whether these EVs could mediate demyelination .

Brain and immune system-derived extracellular vesicles mediate regulation of complement system, extracellular matrix remodeling, brain repair and antigen tolerance in Multiple sclerosis.

Background: Multiple sclerosis (MS) is an immune-mediated central nervous system disease whose course is unpredictable. Finding biomarkers that help to better comprehend the disease's pathogenesis is crucial for supporting clinical decision-making. Blood extracellular vesicles (EVs) are membrane-bound particles secreted by all cell types that contain information on the disease's pathological processes.

Circulating extracellular vesicles promote recovery in a preclinical model of intracerebral hemorrhage.

Circulating extracellular vesicles (EVs) are proposed to participate in enhancing pathways of recovery after stroke through paracrine signaling. To verify this hypothesis in a proof-of-concept study, blood-derived allogenic EVs from rats and xenogenic EVs from humans who experienced spontaneous good recovery after an intracerebral hemorrhage (ICH) were administered intravenously to rats at 24 h after a subcortical ICH. At 28 days, both treatments improved the motor function assessment scales score, showed greater fiber preservation in the perilesional zone (diffusion tensor-fractional anisotropy MRI), increased immunofluorescence markers of myelin (MOG), and decreased astrocyte markers (GFAP) compared with controls.

Functional crosstalk of the glycine transporter GlyT1 and NMDA receptors.

NMDA-type glutamate receptors (NMDARs) constitute one of the main glutamate (Glu) targets in the central nervous system and are involved in synaptic plasticity, which is the molecular substrate of learning and memory. Hypofunction of NMDARs has been associated with schizophrenia, while overstimulation causes neuronal death in neurodegenerative diseases or in stroke. The function of NMDARs requires coincidental binding of Glu along with other cellular signals such as neuronal depolarization, and the presence of other endogenous ligands that modulate their activity by allosterism.

Protein content of blood-derived extracellular vesicles: An approach to the pathophysiology of cerebral hemorrhage.

Extracellular vesicles (EVs) participate in cell-to-cell paracrine signaling and can be biomarkers of the pathophysiological processes underlying disease. In intracerebral hemorrhage, the study of the number and molecular content of circulating EVs may help elucidate the biological mechanisms involved in damage and repair, contributing valuable information to the identification of new therapeutic targets. The objective of this study was to describe the number and protein content of blood-derived EVs following an intracerebral hemorrhage (ICH).

Experimental and Bioinformatic Insights into the Effects of Epileptogenic Variants on the Function and Trafficking of the GABA Transporter GAT-1.

In this article, we identified a novel epileptogenic variant (G307R) of the gene , which encodes the GABA transporter GAT-1. Our main goal was to investigate the pathogenic mechanisms of this variant, located near the neurotransmitter permeation pathway, and compare it with other variants located either in the permeation pathway or close to the lipid bilayer. The mutants G307R and A334P, close to the gates of the transporter, could be glycosylated with variable efficiency and reached the membrane, albeit inactive.

Proximity labeling methods for proteomic analysis of membrane proteins.

Membrane proteins constitute the filter that controls the cellular traffic of nutrients, ions and other essential molecules, as well as the transmission of signals across the membrane. These proteins interact with other proteins in the cytosol, cytoskeleton or the extracellular side of the membrane, giving rise to complex interactomes that are distributed throughout the various lipid microdomains of the membrane plane. In this manner, complex networks of protein-protein and protein-lipid interactions are formed which regulate the most diverse biological functions, and disturbance of these networks can lead to disease.

The Role of Ultrasound as a Diagnostic and Therapeutic Tool in Experimental Animal Models of Stroke: A Review.

Ultrasound is a noninvasive technique that provides real-time imaging with excellent resolution, and several studies demonstrated the potential of ultrasound in acute ischemic stroke monitoring. However, only a few studies were performed using animal models, of which many showed ultrasound to be a safe and effective tool also in therapeutic applications. The full potential of ultrasound application in experimental stroke is yet to be explored to further determine the limitations of this technique and to ensure the accuracy of translational research.

Identification by proximity labeling of novel lipidic and proteinaceous potential partners of the dopamine transporter.

Dopamine (DA) transporters (DATs) are regulated by trafficking and modulatory processes that probably rely on stable and transient interactions with neighboring proteins and lipids. Using proximity-dependent biotin identification (BioID), we found novel potential partners for DAT, including several membrane proteins, such as the transmembrane chaperone 4F2hc, the proteolipid M6a and a potential membrane receptor for progesterone (PGRMC2). We also detected two cytoplasmic proteins: a component of the Cullin1-dependent ubiquitination machinery termed F-box/LRR-repeat protein 2 (FBXL2), and the enzyme inositol 5-phosphatase 2 (SHIP2).

Regulation of the voltage-dependent sodium channel Na1.1 by AKT1.

The voltage-sensitive sodium channel Na1.1 plays a critical role in regulating excitability of GABAergic neurons and mutations in the corresponding gene are associated to Dravet syndrome and other forms of epilepsy. The activity of this channel is regulated by several protein kinases.

Regulation of the Glycine Transporter GLYT1 by microRNAs.

The glycine transporter GLYT1 participates in inhibitory and excitatory neurotransmission by controlling the reuptake of this neuroactive substance from synapses. Over the past few years, microRNAs have emerged as potent negative regulators of gene expression. In this report, we investigate the possible regulation of GLYT1 by microRNAs.

Identification of potassium channel proteins Kv7.2/7.3 as common partners of the dopamine and glutamate transporters DAT and GLT-1.

Dopamine and glutamate transporters (DAT and GLT-1, respectively) share some biophysical characteristics, as both are secondary active carriers coupled to electrochemical ion gradients. In order to identify common or specific components of their respective proteomes, we performed a proximity labelling assay (BioID) in the hippocampal cell line HT22. While most of the identified proteins were specific for each transporter (and will be analyzed elsewhere), we detected two membrane proteins in the shared interactome of GLT-1 and DAT: the transmembrane protein 263 (Tmem263) and the potassium channel protein Kv7.

Identification of novel regulatory partners of the glutamate transporter GLT-1.

We used proximity-dependent biotin identification (BioID) to find proteins that potentially interact with the major glial glutamate transporter, GLT-1, and we studied how these interactions might affect its activity. GTPase Rac1 was one protein identified, and interfering with its GTP/GDP cycle in mixed primary rat brain cultures affected both the clustering of GLT-1 at the astrocytic processes and the transport kinetics, increasing its uptake activity at low micromolar glutamate concentrations in a manner that was dependent on the effector kinase PAK1 and the actin cytoskeleton. Interestingly, the same manipulations had a different effect on another glial glutamate transporter, GLAST, inhibiting its activity.

Activity dependent internalization of the glutamate transporter GLT-1 requires calcium entry through the NCX sodium/calcium exchanger.

GLT-1 is the main glutamate transporter in the brain and its trafficking controls its availability at the cell surface, thereby shaping glutamatergic neurotransmission under physiological and pathological conditions. Extracellular glutamate is known to trigger ubiquitin-dependent GLT-1 internalization from the surface of the cell to the intracellular compartment, yet here we show that internalization also requires the participation of calcium ions. Consistent with previous studies, the addition of glutamate (1 mM) to mixed primary cultures (containing neurons and astrocytes) promotes GLT-1 internalization, an effect that was suppressed in the absence of extracellular Ca.

Glycine Transporters and Its Coupling with NMDA Receptors.

Glycine plays two roles in neurotransmission. In caudal areas like the spinal cord and the brainstem, it acts as an inhibitory neurotransmitter, but in all regions of the CNS, it also works as a co-agonist with L-glutamate at N-methyl-D-aspartate receptors (NMDARs). The glycine fluxes in the CNS are regulated by two specific transporters for glycine, GlyT1 and GlyT2, perhaps with the cooperation of diverse neutral amino acid transporters like Asc-1 or SNAT5/SN2.