Search results for "differentiation"
showing 10 items of 1605 documents
Cyclin-Dependent Kinase 4 Regulates Adult Neural Stem Cell Proliferation and Differentiation in Response to Insulin
2017
Abstract Insulin is one of the standard components used to culture primary neurospheres. Although it stimulates growth of different types of cells, the effects of insulin on adult neural stem cells (NSCs) have not been well characterized. Here, we reveal that insulin stimulates proliferation, but not survival or self-renewal, of adult NSCs. This effect is mediated by insulin receptor substrate 2 (IRS2) and subsequent activation of the protein kinase B (or Akt), leading to increased activity of the G1-phase cyclin-dependent kinase 4 (Cdk4) and cell cycle progression. Neurospheres isolated from Irs2-deficient mice are reduced in size and fail to expand in culture and this impaired proliferati…
Aryl Hydrocarbon Receptor in Keratinocytes Is Essential for Murine Skin Barrier Integrity.
2016
The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor involved in adaptive cell functions, and it is highly active in the epidermis. AhR ligands can accelerate keratinocyte differentiation, but the precise role of AhR in the skin barrier is unknown. Our study showed that transepidermal water loss, a parameter of skin barrier integrity, is high in AhR-deficient mice. Experiments with conditionally AhR-deficient mouse lines identified keratinocytes as the primary cell population responsible for high transepidermal water loss. Electron microscopy showed weaker intercellular connectivity in the epidermis of keratinocytes in AhR-knockout mice, and gene expression analysi…
Electrospun poly(hydroxybutyrate) scaffolds promote engraftment of human skin equivalents via macrophage M2 polarization and angiogenesis.
2018
Human dermo-epidermal skin equivalents (DE) comprising in vitro expanded autologous keratinocytes and fibroblasts are a good option for massive burn treatment. However, the lengthy expansion time required to obtain sufficient surface to cover an extensive burn together with the challenging surgical procedure limits their clinical use. The integration of DE and biodegradable scaffolds has been proposed in an effort to enhance their mechanical properties. Here, it is shown that poly(hydroxybutyrate) electrospun scaffolds (PHB) present good biocompatibility both in vitro and in vivo and are superior to poly-epsilon-caprolactone electrospun scaffolds as a substrate for skin reconstruction. Impl…
Dermal CD207-Negative Migratory Dendritic Cells Are Fully Competent to Prime Protective, Skin Homing Cytotoxic T-Lymphocyte Responses
2018
Dendritic cells (DCs) are important inducers and regulators of T-cell responses. They are able to activate and modulate the differentiation of CD4+ and CD8+ T cells. In the skin, there are at least five phenotypically distinct DC subpopulations that can be distinguished by differential expression of the cell surface markers CD207, CD103, and CD11b. Previous studies have suggested that dermal CD11b−CD207+ conventional type 1 DCs are indispensable for the priming of a skin homing cytotoxic T-lymphocyte response. However, conventional type 1 DCs are also the only skin DC subset capable of cross-presenting exogenous antigens on major histocompatibility complex class I. Thus, it remained unclear…
Early endocrine disruptors exposure acts on 3T3-L1 differentiation and endocrine activity
2017
International audience; Introduction: Data from last years suggested that early exposure to endocrine disruptors (EDs) can predispose newborns to endocrine dysfunction of adipocytes, obesity, and associated disorders. The implication of EDs at low doses on adipocyte development has been poorly investigated. For instance, vinclozolin (V) is a dicarboximide fungicide widely used in agriculture since the 90's, alone or in mixture with genistein (G), an isoflavonoid from Leguminosae. This study aims to identify the effect of vinclozolin alone or with genistein, on adipose tissue properties using cell culture.Methods: In steroid-free conditions, 3T3-L1 pre-adipocytes were induced to differentiat…
Diversity in the Oligodendrocyte Lineage: Current Evidence
2019
Summary Oligodendrocyte progenitor cells (OPCs), which differentiate into myelinating oligodendrocytes during CNS development, are the main proliferative cells in the adult brain. OPCs are conventionally considered a homogeneous population, particularly with respect to their electrophysiological properties, but this has been debated. We show, by using single-cell electrophysiological recordings, that OPCs start out as a homogeneous population but become functionally heterogeneous, varying both within and between brain regions and with age. These electrophysiological changes in OPCs correlate with the differentiation potential of OPCs; thus, they may underlie the differentiational difference…
Transforming growth factor β (CiTGF-β) gene expression is induced in the inflammatory reaction of Ciona intestinalis.
2016
Transforming growth factor (TGF-β) is a well-known component of a regulatory cytokines superfamily that has pleiotropic functions in a broad range of cell types and is involved, in vertebrates, in numerous physiological and pathological processes. In the current study, we report on Ciona intestinalis molecular characterisation and expression of a transforming growth factor β homologue (CiTGF-β). The gene organisation, phylogenetic tree and modelling supported the close relationship with the mammalian TGF suggesting that the C. intestinalis TGF-β gene shares a common ancestor in the chordate lineages. Functionally, real-time PCR analysis showed that CiTGF-β was transcriptionally upregulated …
Macrophage-induced reactive oxygen species promote myometrial contraction and labor-associated mechanisms
2020
AbstractAt labor, the myometrium is infiltrated by a massive influx of macrophages that secrete high levels of pro-inflammatory cytokines inducing the expression of specific labor-associated markers. However, the interactions between myocytes and macrophages and the role of macrophages in the myometrium at labor remain to be elucidated. In this work, we studied the role of myometrium-infiltrated macrophages and their interaction with myocytes in lipopolysaccharide-induced preterm labor. A co-culture model of human primary myometrial cells and macrophages was developed and validated. Collagen lattices were used to evaluate myocyte contraction. Differentiation steps were assessed by (i) phall…
Amphiregulin contained in NSCLC-exosomes induces osteoclast differentiation through the activation of EGFR pathway
2017
AbstractNon-small cell lung cancer (NSCLC) remains the leading cause of cancer-related deaths worldwide. The majority of patients are diagnosed in advanced disease stage. Bone metastasis is the most frequent complication in NSCLC resulting in osteolytic lesions. The perfect balance between bone-resorbing osteoclasts and bone-forming osteoblasts activity is lost in bone metastasis, inducing osteoclastogenesis. In NSCLC, the epidermal growth factor receptor (EGFR) pathway is constitutively activated. EGFR binds Amphiregulin (AREG) that is overexpressed in several cancers such as colon, breast and lung. Its levels in plasma of NSCLC patients correlate with poor prognosis and AREG was recently …
Plasma phospholipid transfer protein (PLTP) modulates adaptive immune functions through alternation of T helper cell polarization
2016
International audience; Objective: Plasma phospholipid transfer protein (PLTP) is a key determinant of lipoprotein metabolism, and both animal and human studies converge to indicate that PLTP promotes atherogenesis and its thromboembolic complications. Moreover, it has recently been reported that PLTP modulates inflammation and immune responses. Although earlier studies from our group demonstrated that PLTP can modify macrophage activation, the implication of PLTP in the modulation of T-cell-mediated immune responses has never been investigated and was therefore addressed in the present study. Approach and results: In the present study, we demonstrated that PLTP deficiency in mice has a pro…