Search results for "Reverse transcriptase"
showing 10 items of 715 documents
Acute activation of cannabinoid receptors by anandamide reduces gastrointestinal motility and improves postprandial glycemia in mice.
2015
International audience; The endocannabinoid system (ECS) is associated with an alteration of glucose homeostasis dependent on cannabinoid receptor-1 (CB1R) activation. However, very little information is available concerning the consequences of ECS activation on intestinal glucose absorption. Mice were injected intraperitoneally with anandamide, an endocannabinoid binding both CB1R and CB2R. We measured plasma glucose and xylose appearance after oral loading, gastrointestinal motility, and glucose transepithelial transport using the everted sac method. Anandamide improved hyperglycemia after oral glucose charge whereas glucose clearance and insulin sensitivity were impaired, pointing out so…
Eicosapentaenoic acid modulates fatty acid metabolism and inflammation in Psammomys obesus.
2015
Abstract The desert gerbil, Psammomys obesus, is a unique polygenic animal model of metabolic syndrome (insulin resistance, obesity and type 2 diabetes), and these pathological conditions resemble to those in human beings. In this study, the animals were fed ad libitum either a natural diet (ND) which contained desertic halophile plants or a standard laboratory diet (STD) or a diet which contained eicosapentaenoic acid (EPA), hence, termed as EPA diet (EPAD). In EPAD, 50% of total lipid content was replaced by EPA oil. By employing real-time PCR, we assessed liver expression of key genes involved in fatty acid metabolism such as PPAR-α, SREBP-1c, LXR-α and CHREBP. We also studied the expres…
Differentiative pathway activated by 3-aminobenzamide, an inhibitor of PARP, in human osteosarcoma MG-63 cells
2004
AbstractThis study describes the molecular mechanism by which treatment with 3-AB, a potent inhibitor of PARP, allows human osteosarcoma MG-63 cells to restrict growth and enter differentiation. Our findings show that in MG-63 cells, aberrant gene expression keeps Rb protein constitutively inactivated through hyperphosphorylation and this promotes uncontrolled proliferation of the cells. After 3-AB-treatment, the poly(ADP-ribosyl)ation of nuclear proteins markedly decreases and this results in an increase in both the hypophosphorylated active form of Rb and pRb/E2F complexes. These effects are accompanied by G1 arrest, downregulation of gene products required for proliferation (cyclin D1, β…
The transcriptional programme of contact-inhibition.
2010
Proliferation of non-transformed cells is regulated by cell-cell contacts, which are referred to as contact-inhibition. Vice versa, transformed cells are characterised by a loss of contact-inhibition. Despite its generally accepted importance for cell-cycle control, little is known about the intracellular signalling pathways involved in contact-inhibition. Unravelling the molecular mechanisms of contact-inhibition and its loss during tumourigenesis will be an important step towards the identification of novel target genes in tumour diagnosis and treatment. To better understand the underlying molecular mechanisms we identified the transcriptional programme of contact-inhibition in NIH3T3 fib…
The down-regulation of miR-125b in chronic lymphocytic leukemias leads to metabolic adaptation of cells to a transformed state
2012
AbstractMiR-125b-1 maps at 11q24, a chromosomal region close to the epicenter of 11q23 deletions in chronic lymphocytic leukemias (CLLs). Our results establish that both aggressive and indolent CLL patients show reduced expression of miR-125b. Overexpression of miR-125b in CLL-derived cell lines resulted in the repression of many transcripts encoding enzymes implicated in cell metabolism. Metabolomics analyses showed that miR-125b overexpression modulated glucose, glutathione, lipid, and glycerolipid metabolism. Changes on the same metabolic pathways also were observed in CLLs. We furthermore analyzed the expression of some of miR-125b–target transcripts that are potentially involved in the…
Altered expression of nonclassical HLA class Ib antigens in human renal cell carcinoma and its association with impaired immune response
2003
Abstract An optimal antitumoral immune response requires the activation of both CD8 + and CD4 + T lymphocytes by the peptide antigen presentation via the human leukocyte antigen (HLA) class I and class II molecules, respectively. Downregulation or loss of HLA molecules has been found in human renal cell carcinoma (RCC) and provides a strategy of these tumors to evade T-cell mediated immunosurveillance. In addition, a tumor-specific upregulation of HLA-G has been recently described in RCC, which also leads to an impaired immune response. We here summarize the frequency of the constitutive and/or interferon-γ (IFN-γ) inducible expression of nonclassical HLA class Ib antigens in RCC cell lines…
Exposure to cadmium chloride influences astrocyte-elevated gene-1 (AEG-1) expression in MDA-MB231 human breast cancer cells
2011
Abstract It is known that cadmium (Cd) is able to regulate gene expression, drastically affecting the pattern of transcriptional activity and intracellular signalization in normal and pathological human cells. We have already shown that Cd exerts a cytotoxic effect on neoplastic MDA-MB231 cells from the human breast, which is characterized by the onset of a “non-classical” apoptotic kind of death, impairment of mitochondrial activity and drastic changes in gene expression pattern. In the present study, employing a combination of conventional and differential display-PCR techniques, immunocytochemical, ELISA and Western analyses, we extended the knowledge on the transcriptional modulation ex…
Cigarette smoke alters IL-33 expression and release in airway epithelial cells
2014
AbstractAirway epithelium is a regulator of innate immune responses to a variety of insults including cigarette smoke. Cigarette smoke alters the expression and the activation of Toll Like Receptor 4 (TLR4), an innate immunity receptor. IL-33, an alarmin, increases innate immunity Th2 responses. The aims of this study were to explore whether mini-bronchoalveolar lavage (mini-BAL) or sera from smokers have altered concentrations of IL-33 and whether cigarette smoke extracts (CSE) alter both intracellular expression (mRNA and protein) and release of IL-33 in bronchial epithelial cells. The role of TLR4 in the expression of IL-33 was also explored.Mini-BALs, but not sera, from smokers show red…
Rapamycin stimulates arginine influx through CAT2 transporters in human endothelial cells
2007
In endothelial cells Tumor Necrosis Factor-alpha (TNFalpha) stimulates arginine transport through the increased expression of SLC7A2/CAT2 transcripts. Here we show that also rapamycin, an inhibitor of mTOR kinase, stimulates system y(+)-mediated arginine uptake in human endothelial cells derived from either saphenous (HSVECs) or umbilical veins (HUVECs). When used together with TNFalpha, rapamycin produces an additive stimulation of arginine transport in both cell models. These effects are observed also upon incubation with AICAR, a stimulator of Adenosine-Monophosphate-dependent-Protein Kinase (AMPK) that produces a rapamycin-independent inhibition of the mTOR pathway. Rapamycin increases …
The Cytokine GM-CSF Drives the Inflammatory Signature of CCR2+ Monocytes and Licenses Autoimmunity.
2015
Granulocyte-macrophage colony-stimulating factor (GM-CSF) has emerged as a crucial cytokine produced by auto-reactive T helper (Th) cells that initiate tissue inflammation. Multiple cell types can sense GM-CSF, but the identity of the pathogenic GM-CSF-responsive cells is unclear. By using conditional gene targeting, we systematically deleted the GM-CSF receptor (Csf2rb) in specific subpopulations throughout the myeloid lineages. Experimental autoimmune encephalomyelitis (EAE) progressed normally when either classical dendritic cells (cDCs) or neutrophils lacked GM-CSF responsiveness. The development of tissue-invading monocyte-derived dendritic cells (moDCs) was also unperturbed upon Csf2r…