Search results for "Extracellular"
showing 10 items of 1220 documents
Negatively Charged Gangliosides Promote Membrane Association of Amphipathic Neurotransmitters
2018
Lipophilic neurotransmitters (NTs) such as dopamine are chemical messengers enabling neurotransmission by adhering onto the extracellular surface of the post-synaptic membrane in a synapse, followed by binding to their receptors. Previous studies have shown that the strength of the NT-membrane association is dependent on the lipid composition of the membrane. Negatively charged lipids such as phosphatidylserine, phosphatidylglycerol, and phosphatidic acid have been indicated to promote NT-membrane binding, however these anionic lipids reside almost exclusively in the intracellular leaflet of the post-synaptic membrane instead of the extracellular leaflet facing the synaptic cleft. Meanwhile…
A role for TASK2 channels in the human immunological synapse.
2020
The immunological synapse is a transient junction that occurs when the plasma membrane of a T cell comes in close contact with an APC after recognizing a peptide from the antigen-MHC. The interaction starts when CRAC channels embedded in the T cell membrane open, flowing calcium ions into the cell. To counterbalance the ion influx and subsequent depolarization, Kv 1.3 and KCa3.1 channels are recruited to the immunological synapse, increasing the extracellular K+ concentration. These processes are crucial as they initiate gene expression that drives T cell activation and proliferation. The T cell-specific function of the K2P channel family member TASK2 channels and their role in autoimmune p…
Extracellular Vesicles in Human Reproduction in Health and Disease.
2017
Extensive evidence suggests that the release of membrane-enclosed compartments, more commonly known as extracellular vesicles (EVs), is a potent newly identified mechanism of cell-to-cell communication both in normal physiology and in pathological conditions. This review presents evidence about the formation and release of different EVs, their definitive markers and cargo content in reproductive physiological processes, and their capacity to convey information between cells through the transfer of functional protein and genetic information to alter phenotype and function of recipient cells associated with reproductive biology. In the male reproductive tract, epididymosomes and prostasomes p…
Endothelial Dab1 signaling orchestrates neuro-glia-vessel communication in the central nervous system.
2018
Developing the bloodbrain barrier During development, signals need to be dynamically integrated by endothelial cells, neurons, and glia to achieve functional neuro-glia-vascular units in the central nervous system. During cortical development, neuronal Dab1 and ApoER2 receptors respond to a guidance cue called reelin. Studying mice, Segarra et al. found that Dab1 and ApoER2 are also expressed in endothelial cells (see the Perspective by Thomas). The integration of reelin signaling in endothelial cells and neurons facilitates the communication between vessels, glia, and neurons that is necessary for the correct positioning of neurons during cortical development. This integration is also impo…
Intranasal Administration of Extracellular Vesicles Derived from Human Teeth Stem Cells Improves Motor Symptoms and Normalizes Tyrosine Hydroxylase E…
2018
Abstract Parkinson's disease (PD) is the second most common neurodegenerative disorder affecting millions of people worldwide. At present, there is no effective cure for PD; treatments are symptomatic and do not halt progression of neurodegeneration. Extracellular vesicles (EVs) can cross the blood–brain barrier and represent promising alternative to the classical treatment strategies. In the present study, we examined therapeutic effects of intranasal administration of EVs derived from human exfoliated deciduous teeth stem cells (SHEDs) on unilateral 6-hydroxydopamine (6-OHDA) medial forebrain bundle (MFB) rat model of PD. CatWalk gait tests revealed that EVs effectively suppressed 6-OHDA-…
Gut Microbiota Restricts NETosis in Acute Mesenteric Ischemia-Reperfusion Injury.
2020
Objective: Recruitment of neutrophils and formation of neutrophil extracellular traps (NETs) contribute to lethality in acute mesenteric infarction. To study the impact of the gut microbiota in acute mesenteric infarction, we used gnotobiotic mouse models to investigate whether gut commensals prime the reactivity of neutrophils towards formation of neutrophil extracellular traps (NETosis). Approach and Results: We applied a mesenteric ischemia-reperfusion (I/R) injury model to germ-free (GF) and colonized C57BL/6J mice. By intravital imaging, we quantified leukocyte adherence and NET formation in I/R-injured mesenteric venules. Colonization with gut microbiota or monocolonization with Esch…
Oligodendrocytes support axonal transport and maintenance via exosome secretion
2020
Neurons extend long axons that require maintenance and are susceptible to degeneration. Long-term integrity of axons depends on intrinsic mechanisms including axonal transport and extrinsic support from adjacent glial cells. The mechanisms of support provided by myelinating oligodendrocytes to underlying axons are only partly understood. Oligodendrocytes release extracellular vesicles (EVs) with properties of exosomes, which upon delivery to neurons improve neuronal viability in vitro. Here, we show that oligodendroglial exosome secretion is impaired in 2 mouse mutants exhibiting secondary axonal degeneration due to oligodendrocyte-specific gene defects. Wild-type oligodendroglial exosomes …
Treatment with albumin-hydroxyoleic acid complex restores sensorimotor function in rats with spinal cord injury: Efficacy and gene expression regulat…
2017
Sensorimotor dysfunction following incomplete spinal cord injury (SCI) is often characterized by paralysis, spasticity and pain. Previously, we showed that intrathecal (i.t.) administration of the albumin-oleic acid (A-OA) complex in rats with SCI produced partial improvement of these symptoms and that oral 2-hydroxyoleic acid (HOA, a non-hydrolyzable OA analogue), was efficacious in the modulation and treatment of nociception and pain-related anxiety, respectively. Here we observed that intrathecal treatment with the complex albumin-HOA (A-HOA) every 3 days following T9 spinal contusion injury improved locomotor function assessed with the Rotarod and inhibited TA noxious reflex activity in…
Genetic deletion of osteopontin in TRAMP mice skews prostate carcinogenesis from adenocarcinoma to aggressive human-like neuroendocrine cancers
2015
// Giorgio Mauri 1 , Elena Jachetti 1 , Barbara Comuzzi 1 , Matteo Dugo 2 , Ivano Arioli 1 , Silvia Miotti 1 , Sabina Sangaletti 1 , Emma Di Carlo 3, 4 , Claudio Tripodo 5 , Mario P. Colombo 1 1 Molecular Immunology Unit, Department of Experimental Oncology and Molecular Medicine, Fondazione IRCCS Istituto Nazionale Tumori, 20133, Milano, Italy 2 Functional Genomics and Bioinformatics, Department of Experimental Oncology and Molecular Medicine, Fondazione IRCCS Istituto Nazionale Tumori, 20133, Milano, Italy 3 Department of Medicine and Science of Aging, Section of Anatomic Pathology and Molecular Medicine, “G. d’Annunzio” University, 66100, Chieti, Italy 4 Ce.S.I. Aging Research Center, “G…
Microvesicles from Human Adipose Tissue-Derived Mesenchymal Stem Cells as a New Protective Strategy in Osteoarthritic Chondrocytes
2018
[EN] Background/Aims: Chronic inflammation contributes to cartilage degeneration during the progression of osteoarthritis (OA). Adipose tissue-derived mesenchymal stem cells (ADMSC) show great potential to treat inflammatory and degradative processes in OA and have demonstrated paracrine effects in chondrocytes. In the present work, we have isolated and characterized the extracellular vesicles from human AD-MSC to investigate their role in the chondroprotective actions of these cells. Methods: AD-MSC were isolated by collagenase treatment from adipose tissue from healthy individuals subjected to abdominal lipectomy surgery. Microvesicles and exosomes were obtained from conditioned medium by…