Differences in Intercellular Communication During Clinical Relapse and Gadolinium-Enhanced MRI in Patients With Relapsing Remitting Multiple Sclerosis: A Study of the Composition of Extracellular Vesicles in Cerebrospinal Fluid.

This study was designed based on the hypothesis that changes in both the levels and surface marker expression of extracellular vesicles (EVs) isolated from the cerebrospinal fluid (CSF) may be associated with the clinical form, disease activity, and severity of multiple sclerosis (MS). The analyzes were performed on subjects affected by MS or other neurological disorders. EVs, which were isolated by ultracentrifugation of CSF samples, were characterized by flow cytometry.

Oxidative stress preconditioning of mouse perivascular myogenic progenitors selects a subpopulation of cells with a distinct survival advantage in vitro and in vivo.

Cell engraftment, survival and integration during transplantation procedures represent the crux of cell-based therapies. Thus, there have been many studies focused on improving cell viability upon implantation. We used severe oxidative stress to select for a mouse mesoangioblast subpopulation in vitro and found that this subpopulation retained self-renewal and myogenic differentiation capacities while notably enhancing cell survival, proliferation and migration relative to unselected cells.

Positive or negative involvement of heat shock proteins in multiple sclerosis pathogenesis: an overview.

Multiple sclerosis (MS) is the most diffuse chronic inflammatory disease of the central nervous system. Both immune-mediated and neurodegenerative processes apparently play roles in the pathogenesis of this disease. Heat shock proteins (HSPs) are a family of highly evolutionarily conserved proteins; their expression in the nervous system is induced in a variety of pathologic states, including cerebral ischemia, neurodegenerative diseases, epilepsy, and trauma.

Extracellular membrane vesicles as a mechanism of cell-to-cell communication: advantages and disadvantages.

Microvesicles represent a newly identified mechanism of intercellular communication. Two different types of microvesicles have been identified: membrane-derived vesicles (EVs) and exosomes. EVs originate by direct budding from the plasma membrane, while exosomes arise from ectocytosis of multivesicular bodies.

Hsp70 and its molecular role in nervous system diseases.

Heat shock proteins (HSPs) are induced in response to many injuries including stroke, neurodegenerative disease, epilepsy, and trauma. The overexpression of one HSP in particular, Hsp70, serves a protective role in several different models of nervous system injury, but has also been linked to a deleterious role in some diseases. Hsp70 functions as a chaperone and protects neurons from protein aggregation and toxicity (Parkinson disease, Alzheimer disease, polyglutamine diseases, and amyotrophic lateral sclerosis), protects cells from apoptosis (Parkinson disease), is a stress marker (temporal lobe epilepsy), protects cells from inflammation (cerebral ischemic injury), has an adjuvant role in antigen presentation and is involved in the immune response in autoimmune disease (multiple sclerosis).

Protective role of heat shock proteins in Parkinson's disease.

Parkinson's disease (PD) is the second most common neurodegenerative disease after Alzheimer's disease. Despite a large amount of research, the pathogenetic mechanism of these diseases has not yet been clarified. Abnormal protein folding, oxidative stress, mitochondrial dysfunction, and apoptotic mechanisms have all been reported as causes of neurodegenerative diseases in association with neuroinflammatory mechanisms which, by generating deleterious molecules, could promote the cascade of events leading to neurodegeneration.

Rapid changes in heat-shock cognate 70 levels, heat-shock cognate phosphorylation state, heat-shock transcription factor, and metal transcription factor activity levels in response to heavy metal exposure during sea urchin embryonic development.

The aim of the present study was to analyze and compare the effects of several metals on the embryos of the sea urchin Paracentrotus lividus, a key species within the Mediterranean Sea ecosystem. Embryos were continuously exposed from fertilization to the following metals: 0.6 mg/l copper, 3 mg/l lead, and 6 mg/l nickel.

Membrane vesicles containing matrix metalloproteinase-9 and fibroblast growth factor-2 are released into the extracellular space from mouse mesoangioblast stem cells.

Certain proteins, including fibroblast growth factor-2 (FGF-2) and matrix metalloproteinase-9 (MMP-9), have proved very effective in increasing the efficacy of mesoangioblast stem cell therapy in repairing damaged tissue. We provide the first evidence that mouse mesoangioblast stem cells release FGF-2 and MMP-9 in their active form through the production of membrane vesicles. These vesicles are produced and turned over continuously, but are stable for some time in the extracellular milieu.

Hsp70 is required for optimal cell proliferation in mouse A6 mesoangioblast stem cells.

Mouse Hsp70 (70 kDa heat shock protein) is preferentially induced by heat or stress stimuli. We previously found that Hsp70 is constitutively expressed in A6 mouse mesoangioblast stem cells, but its possible role in these cells and the control of its basal transcription remained unexplored. Here we report that in the absence of stress, Ku factor is able to bind the HSE (heat shock element) consensus sequence in vitro, and in vivo it is bound to the proximal hsp70 promoter.

Parkinson's disease and cancer: insights for pathogenesis from epidemiology .

Epidemiological evidence suggests a reduced incidence of many common types of cancers in individuals with Parkinson's disease (PD). Parkinson's disease and cancer are two diseases that result from an excessive signaling by one of two forces driving cells to opposite directions. PD results from the excessive death of dopaminergic neurons in the substantia nigra pars compacta (SNc) in the brain, while uncontrolled growth is the key property of cancer.

Hsp70 localizes differently from chaperone Hsc70 in mouse mesoangioblasts under physiological growth conditions.

Mouse A6 mesoangioblasts express Hsp70 even in the absence of cellular stress. Its expression and its intracellular localization were investigated under normal growth conditions and under hyperthermic stress. Immunofluorescence assays indicated that without any stress a fraction of Hsp70 co-localized with actin microfilaments, in the cell cortex and in the contractile ring of dividing cells, while the Hsc70 chaperone did not.

Nickel, lead, and cadmium induce differential cellular responses in sea urchin embryos by activating the synthesis of different HSP70s.

Treatment with heavy metals, such as nickel, lead or cadmium, elicits different cellular stress responses according to the metal used and the length of treatment. In Paracentrotus lividus embryos the inducible forms of HSP70 (HSP70/72) are different in molecular mass from the constitutively expressed HSP75, and they can be used as markers of cellular stress. Even a short treatment with each metal induces the synthesis of HSP70/72 which remain stable for at least 20h and differ little in their isoelectric points.

Localization of HSP70, Cdc2, and cyclin B in sea urchin oocytes in non-stressed conditions.

In Paracentrotus lividus embryos, a Mediterranean sea urchin species, HSP70 is present in all the cells. During cell division it localizes under normal growth conditions on the centrosomes and on the whole isolated mitotic apparatus. Now, in situ hybridization, Western blot analyses, and immunohistochemistry show that the HSP70 mRNA is present in both small and large P.

A study on the effect of the inhibition of polyadenylylation on the production of giant cytoplasmic RNA in sea urchin embryos.

It is suggested that inhibition of RNA polyadenylylation in sea urchin mesenchyme blastulae causes a disturbance of the transport of all the size classes of newly synthesized RNA from the nucleus to the cytoplasm.

Effect of chemical animalization and vegetalization on the synthesis of ribosomal RNA in sea urchin embryos.

Treatment of embryos of Paracentrotus lividus with a concentration of ZnSO which causes animalization, strongly inhibits the initiation of ribosomal RNA synthesis.The vegetalizing agent LiCl does not seem clearly to affect the synthesis of this RNA.