Search results for "Gene Expression"
showing 10 items of 4085 documents
Differential regulation of interleukin-6 expression in human fibroblasts by tumor necrosis factor-alpha and lymphotoxin.
1990
The treatment of human diploid fibroblasts with tumor necrosis factor (TNF)-alpha and with lymphotoxin (LT) is associated with induction of interleukin-6 (IL-6) transcripts with TNF-alpha being 10-fold more potent than LT. Here we report on the TNF-alpha/LT-induced signaling mechanisms responsible for the regulation of IL-6 gene expression in these cells. Run-on assays demonstrated that both TNF-alpha and LT increase IL-6 mRNA levels by transcriptional activation of this gene. Stability studies of IL-6 transcripts in fibroblasts showed that TNF-alpha delayed IL-6 mRNA decay but not LT. The induction of IL-6 transcripts by TNF-alpha and LT was not inhibited by the isoquinoline sulfonamide de…
Zoledronate, ibandronate and clodronate enhance osteoblast differentiation in a dose dependent manner – A quantitative in vitro gene expression analy…
2010
Bisphosphonates are widely used in the clinical treatment of bone diseases with increased bone resorption. In terms of side effects, they are known to be associated with osteonecrosis of the jaw (BONJ). There are two groups of bisphosphonates: the nitrogen-containing bisphosphonates, e.g. zoledronate and ibandronate, and the non-nitrogen-containing bisphosphonates, e.g. clodronate. Their impact on bone metabolism seems to differ. The objective of this study was to compare the osteogenic differentiation potency of these two pharmacologic groups. Human osteoblasts were stimulated with zoledronate and ibandronate at concentrations of 5×10(-5) M, 5×10(-6) M and 5×10(-7) M over the experimental …
Regulation of glomerular basement membrane collagen expression by LMX1B contributes to renal disease in nail patella syndrome.
2001
Basement membrane (BM) morphogenesis is critical for normal kidney function. Heterotrimeric type IV collagen, composed of different combinations of six alpha-chains (1-6), is a major matrix component of all BMs (ref. 2). Unlike in other BMs, glomerular BM (GBM) contains primarily the alpha 3(IV) and alpha 4(IV) chains, together with the alpha 5(IV) chain. A poorly understood, coordinated temporal and spatial switch in gene expression from ubiquitously expressed alpha 1(IV) and alpha 2(IV) collagen to the alpha 3(IV), alpha 4(IV) and alpha 5(IV) chains occurs during normal embryogenesis of GBM (ref. 4). Structural abnormalities of type IV collagen have been associated with diverse biological…
A common mechanism of action of the selective serotonin reuptake inhibitors citalopram and fluoxetine: Reversal of chronic psychosocial stress-induce…
2010
The transcription factor CREB regulates adaptive responses like memory consolidation, addiction, and synaptic refinement. Recently, chronic psychosocial stress as animal model of depression has been shown to stimulate CREB transcriptional activity in the brain; this stimulation was prevented by treatment with the antidepressant imipramine, which inhibits both noradrenaline and serotonin reuptake. However, it was unknown whether the selective inhibition of serotonin reuptake is sufficient for inhibition of stress-induced CREB activation, as it is for the clinical antidepressant effect. Therefore, the effect of two selective serotonin reuptake inhibitors (SSRIs), citalopram and fluoxetine, wa…
Regulation of PTHrP and PTH/PTHrP receptor by extracellular Ca2+ concentration and hormones in the breast cancer cell line 8701-BC.
2000
AbstractIt was previously reported that 8701-BC breast tumour cells express the gene for parathyroid hormonerelated peptide (PTHrP) and PTH/PTHrP receptor (PTHrPR) and release immunoreactive PTHrP (iPTHrP) into the extracellular medium. Since the regulation of PTHrP and PTHrPR by breast cancer cells has been poorly investigated so far, we have chosen the 8701- BC cell line as a model system to investigate whether alterations in the extracellular Ca[2+] concentration ([Ca[2+]]) and treatment with some wellknown differentiation agents for breast cells, such as dimethyl sulfoxide, hydrocortisone, progesterone, prolactin, alltrans retinoic acid and transforming growth factorβ1 might (i) modulat…
Liver specific deletion of CYLDexon7/8 induces severe biliary damage, fibrosis and increases hepatocarcinogenesis in mice
2012
Background & Aims CYLD is a tumor suppressor gene that is mutated in familial cylindromatosis, an autosomal dominant predisposition to tumors of skin appendages. Reduced CYLD expression has been observed in other tumor entities, including hepatocellular carcinoma. In the present study, we analyzed the role of CYLD in liver homeostasis and hepatocarcinogenesis in vivo . Methods Mice with liver-specific deletion of CYLDexon7/8 ( CYLD FF xAlbCre ) were generated. Liver tissues were histologically analyzed and oval cell activation was investigated. Hepatocarcinogenesis was induced by diethylnitrosamine/phenobarbital (DEN/PB). Microarray expression profiling of livers was performed in untreated …
Progestogens reduce thromboxane production by cultured human endothelial cells.
2011
Objectives Progestogens have been poorly studied concerning their roles in endothelial physiology. Prostanoids are vasoactive compounds, such as thromboxane A2, a potent vasoconstrictor, and prostacyclin, a vasodilator. We examined the effects of two progestogens used clinically, progesterone and medroxyprogesterone acetate, on thromboxane A2 production by cultured human umbilical vein endothelial cells (HUVEC) and investigated the role of progesterone receptors and the enzymes involved in production of thromboxane A2 and prostacyclin. Methods Cells were exposed to 1‐100 nmol/l of either progesterone or medroxyprogesterone acetate, and thromboxane A2 production was measured in culture mediu…
Estradiol Stimulates Vasodilatory and Metabolic Pathways in Cultured Human Endothelial Cells
2009
Vascular effects of estradiol are being investigated because there are controversies among clinical and experimental studies. DNA microarrays were used to investigate global gene expression patterns in cultured human umbilical vein endothelial cells (HUVEC) exposed to 1 nmol/L estradiol for 24 hours. When compared to control, 187 genes were identified as differentially expressed with 1.9-fold change threshold. Supervised principal component analysis and hierarchical cluster analysis revealed the differences between control and estradiol-treated samples. Physiological concentrations of estradiol are sufficient to elicit significant changes in HUVEC gene expression. Notch signaling, actin cyt…
Potential role of the neuropeptide CGRP in the induction of differentiation of rat hepatic portal vein wall.
2005
The media of the rat hepatic portal vein is composed of an internal circular muscular layer (CL) and an external longitudinal muscular layer (LL). These two perpendicular layers differentiate progressively from mesenchymal cells within the first month after birth. In this paper, we studied the development of calcitonin gene-related peptide (CGRP) innervation during post-natal differentiation of the vessel. We show that CGRP innervation is already present around the vessel at birth in the future adventitia but far from the lumen of the vessel. Progressively, CGRP immunoreactive fibers reached first LL then CL. CL by itself become only innervated at day 14 after birth. This corresponds to the…
The hypothalamic magnocellular neurosecretory system in developing rats
2009
Studies concerning the development of the magnocellular system are scarce and discordant in literature. We carried out an immunohistochemical study on supraotic and paraventricular hypothalamic nuclei using antivasopressin and antioxytocin antibodies in developing rats between the 15th day of intrauterine life and the 6th day of postnatal life. In addition, we performed RT-PCR experiments to establish the stage at which these hormones appear and neurosecretory activity commences. The results showed that supraoptic and paraventricular nuclei appear, respectively, on the 16th and the 18th day of intrauterine life and both immediately synthetize vasopressin neurohormone. By contrast, synthesis…