Search results for "Down-Regulation"
showing 10 items of 310 documents
Molecular mechanisms of Id2 down-regulation in rat liver after acetaminophen overdose. Protection by N-acetyl-L-cysteine.
2010
Id2 is a pleiotropic protein whose function depends on its expression levels. Id2-deficient cells show increased cell death. This study explored the molecular mechanisms for the modulation of Id2 expression elicited by GSH and oxidative stress in the liver of acetaminophen (APAP)-intoxicated rats. APAP-overdose induced GSH depletion, Id2 promoter hypoacetylation, RNApol-II released and, therefore, Id2 down-regulation. Id2 expression depends on c-Myc binding to its promoter. APAP-overdose decreased c-Myc content and binding to Id2 promoter. Reduction of c-Myc was not accompanied by decreased c-myc mRNA, suggesting a mechanism dependent on protein stability. Administration of N-acetyl-cystein…
Enhanced characterization of serum autoantibody reactivity following HSP 60 immunization in a rat model of experimental autoimmune glaucoma.
2010
Antibodies against heat shock proteins have been identified in sera of human glaucoma patients in several studies and immunization with heat shock protein 60 (HSP 60) causes retinal ganglion cell (RGC) loss in an animal model of experimental autoimmune glaucoma. The aim of this study was to observe the time course of increased anti-retina antibody appearance in the serum and characterize the identification of prominent autoantibodies that accompany HSP 60 immunization in a rat model of experimental autoimmune glaucoma.Eight weeks after immunization with HSP 60 retinal flatmounts were prepared and RGCs were counted in eight predefined areas and compared to controls. Serum collected before, a…
Anti-inflammatory and joint protective effects of extra-virgin olive-oil polyphenol extract in experimental arthritis
2014
The consumption of extra virgin olive oil (EVOO) in Mediterranean countries has shown beneficial effects. A wide range of evidence indicates that phenolic compounds present in EVOO are endowed with anti-inflammatory properties. In this work, we evaluated the effects of EVOO-polyphenol extract (PE) in a model of rheumatoid arthritis, the collagen-induced arthritis model in mice. On day 0, DBA-1/J mice were immunized with bovine type II collagen. On day 21, mice received a booster injection. PE (100 and 200 mg/kg) was orally administered once a day from days 29 to 41 to arthritic mice. We have demonstrated that PE decreases joint edema, cell migration, cartilage degradation and bone erosion. …
Down regulation of CD11b and CD18 expression in children with hypercholesterolemia: A preliminary report.
2009
BACKGROUND AND AIM: Cell adhesion molecules play an important role in the development of atherosclerosis mediating the attachment of monocytes to the endothelium. The aim of our study was to assess the cell surface expression of CD11b/CD18 integrin on the phagocytes of children affected by hypercholesterolemia. METHODS AND RESULTS: Twenty-six children with hypercholesterolemia (15 males, mean age 8.3, range 2-18) with a family history of early cardiovascular disease, as well as 26 children with normocholesterolemia matched for gender and age (15 males, mean age 8.3) were studied. Cell surface expression of CD11b/CD18 on peripheral blood mononuclear cells (PBMC) were analyzed by flow cytomet…
Changes in the expression of cation-Cl- cotransporters, NKCC1 and KCC2, during cortical malformation induced by neonatal freeze-lesion.
2007
Focal cortical malformations comprise a heterogeneous group of disturbances in brain development, often associated with intractable epilepsy. A focal freeze-lesion of cerebral cortex in newborn rat produces a cortical malformation that resembles human polymicrogyria, clinical conditions that results from abnormal neuronal migration. The change in GABAergic functions that occurs during early brain development is induced by an alteration in Cl(-) homeostasis and plays important roles in neocortical development by modulating such events as laminar organization and synaptogenesis. We therefore investigated the relationship between pathogenesis of polymicrogyria and ontogeny of Cl(-) homeostasis…
Nitric oxide- and cGMP-active compounds affect the discharge of substantia nigra pars reticulata neurons: in vivo evidences in the rat
2009
The nitric oxide (NO)-active drugs influence on the bioelectric activity of neurons of the pars reticulata of the substantia nigra was studied in urethane-anesthetized rats. A first group of animals was treated with 7-nitro-indazole (7-NI), a preferential inhibitor of neuronal NO synthase. In a second group of rats, electrophysiological recordings were coupled with microiontophoretic administration of Nomega-nitro-L-arginine methyl ester (L-NAME, a NO synthase inhibitor), 3-morpholino-sydnonimin-hydrocloride (SIN-1, a NO donor) and 8-Br-cGMP (a cell-permeable analogue of cGMP, the main second-messenger of NO neurotransmission). 7-NI and L-NAME caused a statistically significant decrease in …
Downregulation of β2-microglobulin in human cord blood somatic stem cells after transplantation into livers of SCID-mice: an escape mechanism of stem…
2002
Adherently growing, non-hematopoietic somatic stem cells isolated from human cord blood were stained with the fluorescent dye PKH26 and transplanted into livers of SCID-mice to examine a possible cell fate transition. Already 7 days after transplantation stem cells were well integrated into the liver tissue. Human albumin that was not expressed by the stem cells before transplantation was detectable in the host's livers after injection of cord blood stem cells. Human alpha1-antitrypsin was detectable in stem cells already before transplantation and remained positive in the mouse liver. The most interesting observation in this study was the downregulation of human beta2-microglobulin (beta2M…
Chronic lithium salt treatment reduces CRE/CREB-directed gene transcription and reverses its upregulation by chronic psychosocial stress in transgeni…
2007
The molecular mechanism of action of the mood stabilizer lithium is assumed to involve changes in gene expression leading to neuronal adaptation. The transcription factor CREB (cAMP-responsive element binding protein) regulates the expression of many genes and has been implicated in important brain functions and the action of psychogenic agents. We here investigated the effect of lithium on cAMP-responsive element (CRE)/CREB-mediated gene transcription in the brain, using transgenic reporter mice that express the luciferase reporter gene under the control of four copies of the rat somatostatin gene promoter CRE. Chronic (21 days) but not acute (24 h) treatment with lithium (7.5 mmol/kg) sig…
Glucocorticoid receptor knockdown decreases the antioxidant protection of B16 melanoma cells: an endocrine system-related mechanism that compromises …
2014
We previously reported an interorgan system in which stress-related hormones (corticosterone and noradrenaline), interleukin-6, and glutathione (GSH) coordinately regulate metastatic growth of highly aggressive B16-F10 melanoma cells. Corticosterone, at levels measured in tumor-bearing mice, also induces apoptotic cell death in metastatic cells with low GSH content. In the present study we explored the potential role of glucocorticoids in the regulation of metastatic cell death/survival during the early stages of organ invasion. Glucocorticoid receptor (GCR) knockdown decreased the expression and activity of γ-glutamylcysteine synthetase (γ-GCS), the rate-limiting step in GSH synthesis, in …
Activation of a ΔFOSB dependent gene expression pattern in the dorsolateral prefrontal cortex of patients with major depressive disorder
2010
Abstract Background A ΔFOSB mediated transcriptional response in the nucleus accumbens (NAc) is induced by chronic social stress in rodent and a 50% down-regulation of ΔFOSB has been also reported in the NAc of eight depressed subjects. To evaluate the role of ΔFOSB in the prefrontal cortex which is critically involved in negative cognitive bias associated with major depressive disorder (MDD) we have quantified the mRNA levels of ΔFOSB and of five of its major target genes in the Brodmann area 46 from 24 patients with MDD (11 with psychotic symptoms) and 12 controls. Method Expression of the six genes has been quantified by a real-time quantitative PCR method: ΔFOSB , GRIA2 (encoding the Gl…