Search results for "Cell Movement"
showing 10 items of 396 documents
Defective Postnatal Neurogenesis and Disorganization of the Rostral Migratory Stream in Absence of theVax1Homeobox Gene
2004
The subventricular zone (SVZ) is one of the sources of adult neural stem cells (ANSCs) in the mouse brain. Precursor cells proliferate in the SVZ and migrate through the rostral migratory stream (RMS) to the olfactory bulb (OB), where they differentiate into granule and periglomerular cells. Few transcription factors are known to be responsible for regulating NSC proliferation, migration, and differentiation processes; even fewer have been found to be responsible for the organization of the SVZ and RMS. For this reason, we studied the ventral anterior homeobox (Vax1) gene in NSC proliferation and in SVZ organization. We found thatVax1is strongly expressed in the SVZ and in the RMS and that,…
Sustained activation of mTOR pathway in embryonic neural stem cells leads to development of tuberous sclerosis complex-associated lesions
2011
SummaryTuberous Sclerosis Complex (TSC) is a multisystem genetic disorder characterized by hamartomatous neurological lesions that exhibit abnormal cell proliferation and differentiation. Hyperactivation of mTOR pathway by mutations in either the Tsc1 or Tsc2 gene underlies TSC pathogenesis, but involvement of specific neural cell populations in the formation of TSC-associated neurological lesions remains unclear. We deleted Tsc1 in Emx1-expressing embryonic telencephalic neural stem cells (NSCs) and found that mutant mice faithfully recapitulated TSC neuropathological lesions, such as cortical lamination defects and subependymal nodules (SENs). These alterations were caused by enhanced gen…
LAAE-14, a new in vitro inhibitor of intracellular calcium mobilization, modulates acute and chronic inflammation.
2003
Abstract A new lipidic acid-amido ether derivative (LAAE-14) able to reduce dose-dependently the calcium increases mediated either by calcium ionophore ionomycin, by the endoplasmic reticular Ca 2+ -ATPase inhibitor thapsigargin, or by the chemotactic tripeptide N -formyl- l -methionyl- l -leucyl- l -phenylalanine (fMLP), in human neutrophils as well as in murine peritoneal macrophages, but not ATP, has been evaluated as a potential anti-inflammatory drug. This compound attenuated leukocyte activation by means of its inhibitory effect on the respiratory burst elicited in both types of cells by 12- O -tetradecanoyl phorbol 13-acetate, by inhibition of the degranulation process induced by cyt…
NG2 regulates directional migration of oligodendrocyte precursor cells via Rho GTPases and polarity complex proteins.
2013
The transmembrane proteoglycan NG2 is expressed by oligodendrocyte precursor cells (OPC), which migrate to axons during developmental myelination and remyelinate in the adult after migration to injured sites. Highly invasive glial tumors also express NG2. Despite the fact that NG2 has been implicated in control of OPC migration, its mode of action remains unknown. Here, we show in vitro and in vivo that NG2 controls migration of OPC through the regulation of cell polarity. In stab wounds in adult mice we show that NG2 controls orientation of OPC toward the wound. NG2 stimulates RhoA activity at the cell periphery via the MUPP1/Syx1 signaling pathway, which favors the bipolar shape of migrat…
Cytotoxicity and bioactivity of various pulpotomy materials on stem cells from human exfoliated primary teeth.
2017
Aims To investigate the cytotoxicity and bioactivity of several pulpotomy materials: Biodentine (Septodont, Saint-Maur-des-Fosses, France) MTA (Angelus, Londrina, PR, Brazil), Theracal LC (Bisco Inc., Schamburg, IL, USA) and IRM (Dentsply DeTrey GmbH, Konstanz, Germany), after contact with stem cells isolated from human exfoliated primary teeth (SHEDs). Methodology SHEDs were cultured in the presence of the eluates of various pulpotomy materials for 24, 48 and 72 h. Cell viability was determined by mitochondrial dehydrogenase enzymatic (MTT) assay. Apoptosis and changes in cell phenotype were evaluated by flow cytometry. Also, an in vitro scratch wound-healing assay was used to determine th…
Let-7d miRNA Shows Both Antioncogenic and Oncogenic Functions in Osteosarcoma-Derived 3AB-OS Cancer Stem Cells
2015
Osteosarcoma (OS), an aggressive highly invasive and metastatic bone-malignancy, shows therapy resistance and recurrence, two features that likely depend on cancer stem cells (CSCs), which hold both self-renewing and malignant potential. So, effective anticancer therapies against OS should specifically target and destroy CSCs. We previously found that the let-7d microRNA was downregulated in the 3AB-OS-CSCs, derived from the human OS-MG63 cells. Here, we aimed to assess whether let-7d modulation affected tumorigenic and stemness properties of these OS-CSCs. We found that let-7d-overexpression reduced cell proliferation by decreasing CCND2 and E2F2 cell-cycle-activators and increasing p21 an…
Profilin1 regulates sternum development and endochondral bone formation.
2012
Bone development is a dynamic process that requires cell motility and morphological adaptation under the control of actin cytoskeleton. This actin cytoskeleton system is regulated by critical modulators including actin-binding proteins. Among them, profilin1 (Pfn1) is a key player to control actin fiber structure, and it is involved in a number of cellular activities such as migration. During the early phase of body development, skeletal stem cells and osteoblastic progenitor cells migrate to form initial rudiments for future skeletons. During this migration, these cells extend their process based on actin cytoskeletal rearrangement to locate themselves in an appropriate location within mic…
In human endothelial cells rapamycin causes mTORC2 inhibition and impairs cell viability and function.
2008
Aim Drug-eluting stents are widely used to prevent restenosis but are associated with late endothelial damage. To understand the basis for this effect, we have studied the consequences of a prolonged incubation with rapamycin on the viability and functions of endothelial cells. Methods and results Human umbilical vein or aorta endothelial cells were exposed to rapamycin in the absence or in the presence of tumour necrosis factor α (TNFα). After a 24 h-incubation, rapamycin (100 nM) caused a significant cell loss associated with the increase of both apoptosis and necrosis, as quantified by propidium iodide staining, caspase 3 activity, and lactate dehydrogenase release. Rapamycin also impair…
Multipotent Neural Stem Cells Reside into the Rostral Extension and Olfactory Bulb of Adult Rodents
2002
The lateral walls of the forebrain lateral ventricles are the richest source of stem cells in the adult mammalian brain. These stem cells give rise to new olfactory neurons that are renewed throughout life. The neurons originate in the subventricular zone (SVZ), migrate within the rostral extension (RE) of the SVZ along the rostral migratory stream (RMS) within tube-like structures formed of glial cells, to eventually reach the olfactory bulb (OB). We demonstrate that, contrary to the current view, multipotential (neuronal-astroglial-oligodendroglial) precursors with stem cell features can be isolated not only from the SVZ but also from the entire RE, including the distal portion within the…
Damping excessive inflammation and tissue damage in Mycobacterium tuberculosis infection by Toll IL-1 receptor 8/single Ig IL-1-related receptor, a n…
2007
Abstract Toll IL-1R 8/single Ig IL-1-related receptor (TIR8/SIGIRR) is a member of the IL-1R family, expressed by epithelial tissues and immature dendritic cells, and is regarded as a negative regulator of TLR/IL-1R signaling. Tir8-deficient mice were rapidly killed by intranasal administration of low doses of Mycobacterium tuberculosis, despite controlling efficiently the number of viable bacilli in different organs. Tir8−/−-infected mice showed an increased number of neutrophils and macrophages in the lungs; however, mycobacteria-specific CD4 and CD8 T cells were similar in Tir8−/− and Tir8+/+ mice. Exaggerated mortality of Tir8−/− mice was due to massive liver necrosis and was accompanie…