Search results for "Expression"
showing 10 items of 5168 documents
Nitric oxide synthase: expression and expressional control of the three isoforms.
1995
Three isozymes of nitric oxide synthase (NOS) have been identified. Their cDNA- and protein structures as well as their genomic DNA structures have been described. NOS I (ncNOS, originally discovered in neurons) and NOS III (ecNOS, originally discovered in endothelial cells) are low output, Ca(2+)-activated enzymes whose physiological function is signal transduction. NOS II (iNOS, originally discovered in cytokine-induced macrophages) is a high output enzyme which produces toxic amounts of NO that represent an important component of the antimicrobial, antiparasitic and antineoplastic activity of these cells. Depending on the species, NOS II activity is largely (human) or completely (mouse a…
Inhibiting proliferation in KB cancer cells by RNA interference-mediated knockdown of nicotinamide N-methyltransferase expression.
2011
The enzyme Nicotinamide N-methyltransferase (NNMT) catalyzes the methylation of nicotinamide and other pyridines, playing a pivotal role in the biotransformation and detoxification of many drugs and xenobiotic compounds. Several tumours have been associated with abnormal NNMT expression, however its role in tumour development remains largely unknown. In this study we investigated expression levels of Nicotinamide N-methyltransferase in a cancer cell line and we evaluated the effect of shRNA-mediated silencing of NNMT on cell proliferation. Cancer cells were examined for NNMT expression by semiquantitative RT-PCR and Western blot analysis. A HPLC-based catalytic assay was performed to asses…
Genetics of the variable expression of CYP3A in humans.
2004
CYP3A isozymes participate in the metabolism of 45-60% of currently used drugs and of a variety of other compounds such as steroid hormones, toxins, and carcinogens. The CYP3A expression status is a major determinant of drug efficacy and safety, and it may also affect an individual's predisposition to certain cancers. The inter- and intraindividual expression of CYP3A is variable because of a complex interplay between genetic and environmental factors. Markers predictive of the individual CYP3A activity could improve therapies with CYP3A substrates by personalised dose adjustments, but their development has been slower than for other drug-metabolizing enzymes. Here we summarize the recent p…
Murine embryonic stem cell line CGR8 expresses all subtypes of muscarinic receptors and multiple nicotinic receptor subunits: Down-regulation of α4- …
2015
Non-neuronal acetylcholine mediates its cellular effects via stimulation of the G-protein-coupled muscarinic receptors and the ligand-gated ion channel nicotinic receptors. The murine embryonic stem cell line CGR8 synthesizes and releases non-neuronal acetylcholine. In the present study a systematic investigation of the expression of nicotinic receptor subunits and muscarinic receptors was performed, when the stem cells were grown in the presence or absence of LIF, as the latter condition induces early differentiation. CGR8 cells expressed multiple nicotinic receptor subtypes (α3, α4, α7, α9, α10, β1, β2, β3, β4, γ, δ, e) and muscarinic receptors (M1, M3, M4, M5); M2 was detected only in 2 …
Recent progress in revealing the biological and medical significance of the non-neuronal cholinergic system.
2015
This special issue of International Immunopharmacology is the proceedings of the Fourth International Symposium on Non-neuronal Acetylcholine that was held on August 28-30, 2014 at the Justus Liebig University of Giessen in Germany. It contains original contributions of meeting participants covering the significant progress in understanding of the biological and medical significance of the non-neuronal cholinergic system extending from exciting insights into molecular mechanisms regulating this system via miRNAs over the discovery of novel cholinergic cellular signaling circuitries to clinical implications in cancer, wound healing, immunity and inflammation, cardiovascular, respiratory and …
Effects of Glyburide-Cyclosporin A Interaction on Interleukin-2 Production in Rats1
1999
The effects of simultaneous administrations of Cyclosporin A (CsA) and Glyburide on the immune system of rats has been evaluated in terms of Interleukin-2 (IL-2) production by Concanavalin A (ConA) stimulated splenocytes and exogenous IL-2 binding capacity. The inhibitory effect of Cyclosporin A on IL-2 production of lymphoid cells is well known. Spleen cells from rats receiving CsA had reduced levels of IL-2 when compared to untreated controls or rats receiving Glyburide only. Splenocytes from rats receiving both drugs had reduced levels of IL-2 when they were sacrificed 24 hours after one or three CsA administrations; instead when the animals were sacrificed 6 days after three CsA adminis…
Cytokine induction of NO synthase II in human DLD-1 cells: roles of the JAK-STAT, AP-1 and NF-κB-signaling pathways
1998
1. In human epithelial-like DLD-I cells, nitric oxide synthase (NOS) II expression was induced by interferon-gamma (100 u ml(-1)) alone and, to a larger extent, by a cytokine mixture (CM) consisting of interferon-gamma, interleukin-1beta (50 u ml(-1)) and tumor necrosis factor-alpha (10 ng ml(-1)). 2. CM-induced NOS II expression was inhibited by tyrphostin B42 (mRNA down to 1%; nitrite production down to 0.5% at 300 microM) and tyrphostin A25 (mRNA down to 24%, nitrite production down to 1% at 200 microM), suggesting the involvement of janus kinase 2 (JAK-2). Tyrphostin B42 also blocked the CM-induced JAK-2 phosphorylation (kinase assay) and reduced the CM-stimulated STAT1alpha binding act…
Autoimmune biomarkers in glaucoma patients.
2013
There is growing evidence showing an autoimmune involvement in the pathogenesis of glaucoma, and that alterations in natural occurring autoantibody levels play a key role. The upregulation of autoantibodies can be associated with fatal conditions, but several studies demonstrate that natural autoantibodies entail also protective characteristics and influence the protein expression of neuroretinal cells. A disbalance of natural occurring autoantibodies may shift the physiological equilibrium of protective immunity leading to a predisposition for developing glaucoma. This article highlights recent advances in understanding of autoimmune mechanisms in the pathogenesis of glaucoma.
Transcriptional regulation and expression of CYP3A4 in hepatocytes.
2007
CYP3A4 is the most abundantly expressed drug-metabolizing P450 enzyme in human liver and contributes to the metabolism of a large number of drugs in use today. CYP3A4 is constitutively expressed in adult hepatocytes but it can also be transcriptionally induced by a variety of structurally diverse xenochemicals. CYP3A4 strongly contributes to the important variability in the therapeutic and toxic effects of drugs owing to the major role it plays in xenobiotic metabolism and the large intra- and inter-individual variability to which it is subjected. The functional examination of up to 13 kb of the CYP3A4 5'-flanking region has revealed that the regulation of this gene is a complex issue, with…
The carbon monoxide-releasing molecule CORM-2 inhibits the inflammatory response induced by cytokines in Caco-2 cells
2007
Background and purpose: Recent evidence indicates that carbon monoxide-releasing molecules (CO-RMs) exhibit potential anti-inflammatory properties. In the present study, we have investigated whether tricarbonyl dichloro ruthenium(II) dimer (CORM-2) can control the inflammatory response induced by cytokines in a human colonic epithelial cell line, Caco-2. Experimental approach: Caco-2 cells were preincubated with CORM-2 for 30 minutes and then stimulated with interleukin (IL)-1β, tumor necrosis factor-α and interferon-γ for different times. Gene expression was analyzed by real-time PCR. Protein expression was investigated by Western blot and ELISA. Transcription factor activation was determi…