Search results for "messenger"
showing 10 items of 1493 documents
LPS challenge regulates gene expression and tissue localization of a Ciona intestinalis gene through an alternative polyadenylation mechanism.
2013
A subtractive hybridization strategy for the identification of differentially expressed genes was performed between LPS-challenged and naive Ciona intestinalis. This strategy allowed the characterization of two transcripts (Ci8short and Ci8long) generated by the use of two Alternative Polyadenylation sites. The Ci8long transcript contains a protein domain with relevant homology to several components of the Receptor Transporting Protein (RTP) family not present in the Ci8short mRNA. By means of Real Time PCR and Northern Blot, the Ci8short and Ci8long transcripts showed a different pattern of gene expression with the Ci8short mRNA being strongly activated after LPS injection in the pharynx. …
The RNA binding protein tristetraprolin influences the activation state of murine dendritic cells
2010
Abstract Dendritic cells (DCs) serve to maintain peripheral tolerance under steady state conditions. Upon triggering by activation signals they initiate strong immune responses. The activation of DCs is accompanied by a rapid upregulation of proinflammatory cytokines, which were shown in other cell types to be regulated by mechanisms at the transcriptional and posttranscriptional level. Tristetraprolin (TTP), an important RNA binding protein, is involved in the regulation of mRNA stability of such cytokines. In this study we analyzed the significance of TTP for mouse DCs, which were derived from TTP −/− and WT bone marrow progenitor cells (BM-DCs). Unstimulated BM-DCs of TTP −/− mice expres…
Regulation of hematopoietic growth factor production by genetically modified human bone marrow stromal cells expressing interleukin-1beta antisense R…
2001
Interleukin-1 (IL-1) plays a major role in the regulation of bone marrow stromal cell function and hematopoiesis. It is known to induce secretion of the hematopoietic growth factors granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage CSF (GM-CSF), IL-6, and IL-8 as well as IL-1 itself in stromal cells. We investigated the role of IL-1beta-mediated growth factor production in the human stromal cell line L88/5. Using liposome-mediated DNA transfer, two stromal cell transfectants that constitutively express IL-1beta antisense (AS) RNA were generated. Expression of IL-1beta AS RNA and IL-1beta RNA was determined by RT-PCR. The stromal cell transfectants were strongly impaired …
Effect of indomethacin on the kinetics of tumour necrosis factor alpha release and tumour necrosis factor alpha gene expression by human blood monocy…
1991
Summary In this investigation we have examined the effects of indomethacin, an inhibitor of the cyclooxygenase pathway of arachidonic acid, upon the kinetics of the release of tumour necrosis factor alpha (TNF) and of the expression of TNF gene by lipopolysaccharide (LPS)-stimulated human blood monocytes (BM). Following stimulation of BM with LPS, TNF was released within 2 h, reached peak values at 8 h and declined at subsequent time-points (24 and 48 h). Indomethacin (10−5 m ) slightly stimulated the production of TNF at 2, 4, and 8 h and prevented the decline of TNF observed at 24 and 48 h. This effect was related to the persistence of TNF synthesis, as demonstrated by kinetics evaluation…
Characterization of two alternative Interleukin(IL)-10 5′UTR mRNA sequences, induced by lipopolysaccharide (LPS) stimulation of peripheral blood mono…
2009
Abstract IL-10 production shows a broad-spectrum of individual response, suggesting a genetic component of approximately 75%. Different polymorphisms located close to, or within the IL-10 gene has been demonstrated to influence its transcription rate whereas the post-transcriptional regulation of IL-10 production has not well elucidated. The main responsible elements at this control level are both the 5′- and 3′-untranslated regions (UTR's) of mRNAs, and as the 3′-UTR regions are mainly involved in the stability and decay rate of mRNAs, the 5′-UTR regions mediate the binding rate of the molecule with ribosomal 40S subunit as a cis-acting element. Herein are report data on the identification…
Tissue inhibitor of metalloproteinases-2 (TIMP-2) in rat liver cells is increased by lipopolysaccharide and prostaglandin E2
1995
AbstractTo explore the functional role of TIMP-2 in liver, we determined TIMP-2 mRNA levels in primary rat hepatocytes and in total rat liver. Rat hepatocytes constitutively express TIMP-2 mRNA at a low level. Incubation with dexamethasone, prostaglandin E2 and a combination of inflammatory cytokines leads to an up-regulation of TIMP-2 mRNA. In rats in vivo we found a dramatic increase of TIMP-2 expression after intraperitoneal injection of lipopolysaccharide. Compared to our previous findings on TIMP-1 we conclude that TIMP-2 mRNA expression is regulated in a distinct and partially opposite manner. Over-production of TIMP-2 could inhibit the activity of metalloproteinases and thus lead to …
MERTK rs4374383 polymorphism affects the severity of fibrosis in non-alcoholic fatty liver disease
2015
Background & Aim Homozygosity for a common non-coding rs4374383 G>A polymorphism in MERTK (myeloid-epithelial-reproductive tyrosine kinase) has been associated with the protection against fibrosis progression in chronic hepatitis C. The main study objective was to assess whether MERTK AA genotype influences liver fibrosis, and secondarily MERTK expression in patients with non-alcoholic fatty liver disease (NAFLD). We also investigated whether MERTK is expressed in human hepatic stellate cells (HSC) and in murine models of fibrogenesis. Methods We considered 533 consecutive patients who underwent liver biopsy for suspected non-alcoholic steatohepatitis (NASH) without severe obesity from two …
The lipid lowering drug lovastatin protects against doxorubicin-induced hepatotoxicity.
2012
Liver is the main detoxifying organ and therefore the target of high concentrations of genotoxic compounds, such as environmental carcinogens and anticancer drugs. Here, we investigated the usefulness of lovastatin, which is nowadays widely used for lipid lowering purpose, as a hepatoprotective drug following the administration of the anthracycline derivative doxorubicin in vivo. To this end, BALB/c mice were exposed to either a single high dose or three consecutive low doses of doxorubicin. Acute and subacute hepatotoxicities were analyzed with or without lovastatin co-treatment. Lovastatin protected the liver against doxorubicin-induced acute pro-inflammatory and pro-fibrotic stress respo…
Reduced mRNA abundance of the main enzymes involved in methionine metabolism in human liver cirrhosis and hepatocellular carcinoma
2000
Abstract Background/Aims: It has been known for at least 50 years that alterations in methionine metabolism occur in human liver cirrhosis. However, the molecular basis of this alteration is not completely understood. In order to gain more insight into the mechanisms behind this condition, mRNA levels of methionine adenosyltransferase ( MAT1A ), glycine methyltransferase ( GNMT ), methionine synthase ( MS ), betaine homocysteine methyltransferase ( BHMT ) and cystathionine β-synthase ( CBS ) were examined in 26 cirrhotic livers, five hepatocellular carcinoma (HCC) tissues and ten control livers. Methods: The expression of the above-mentioned genes was determined by quantitative RT-PCR analy…
Fibroblast Growth Factor 21 Limits Lipotoxicity by Promoting Hepatic Fatty Acid Activation in Mice on Methionine and Choline-Deficient Diets
2014
Background & Aims Nonalcoholic fatty liver disease is a common consequence of human and rodent obesity. Disruptions in lipid metabolism lead to accumulation of triglycerides and fatty acids, which can promote inflammation and fibrosis and lead to nonalcoholic steatohepatitis. Circulating levels of fibroblast growth factor (FGF)21 increase in patients with nonalcoholic fatty liver disease or nonalcoholic steatohepatitis; therefore, we assessed the role of FGF21 in the progression of murine fatty liver disease, independent of obesity, caused by methionine and choline deficiency. Methods C57BL/6 wild-type and FGF21-knockout (FGF21-KO) mice were placed on methionine- and choline-deficient (MCD)…