Search results for "Liver Regeneration"
showing 10 items of 40 documents
Combined interleukin 6 and soluble interleukin 6 receptor accelerates murine liver regeneration.
2000
Abstract Background & Aims: Liver regeneration after loss of hepatic tissue leads to hepatocyte and nonparenchymal cell proliferation and rapid restoration of liver parenchyma. Interleukin (IL)-6 is a key inducer of transcription factors involved in liver regeneration. Whenever IL-6 activates target cells, it binds to a specific IL-6 receptor (IL-6R). The IL-6/IL-6R complex then associates with the signal transducer gp130, leading to activation of intracellular signaling. Methods: We have recently constructed the designer cytokine Hyper-IL-6 consisting of soluble IL-6R covalently linked to IL-6, which directly stimulates gp130 even in the absence of membrane-bound IL-6R. We compared the inf…
Intracellular accumulation of incompletely processed transforming growth factor-alpha polypeptides in ground glass hepatocytes of chronic hepatitis B…
1996
Abstract Background: Transforming growth factor-alpha is an intracellularly processed and secreted polypeptide that induces a proliferative response in epithelial target cells and represents a potential regulatory factor in embryonic development, liver regeneration, and also hepatocarcinogenesis. We have observed focal transforming growth factor-alpha expression in liver tissues with chronic hepatitis B virus infection. Methods: To further elucidate the nature of this focal transforming growth factor-alpha accumulation were have analyzed overall 23 different liver tissues with chronic hepatitis B virus and hepatitis C virus infection as well as normal liver tissues by immunohistology, ELISA…
Trichinella spiralisThymidylate Synthase: Developmental Pattern, Isolation, Molecular Properties, and Inhibition by Substrate and Cofactor Analogues
1996
Abstract Thymidylate synthase specific activity was found to remain at a constant level in crude extracts from muscle larvae, isolated (1-15 months after infection) by pepsin-HCl digestion, as well as from adult worms ofTrichinella spiralis.The enzyme was purified and its molecular (monomer mol. wt 35 kD) and kinetic (sequential mechanism with the Kmvalues 3.1 and 19 μM for dUMP and N5,10-methylenetetrahydrofolate, respectively) properties determined. 5-Fluoro-dUMP was a competitive, slow-binding inhibitor of the parasite enzyme. N5,10-methylenetetrahydrofolate analogues 10-propargyl-5,8-dideazafolate (CB3717), ZD1694, BW1843U89, and AG337 were weaker inhibitors of the parasite than regener…
Nucleosome-specific, Time-dependent Changes in Histone Modifications during Activation of the Early Growth Response 1 (Egr1) Gene
2014
Histone post-translational modifications and nucleosome remodeling are coordinate events involved in eukaryotic transcriptional regulation. There are relatively few data on the time course with which these events occur in individual nucleosomes. As a contribution to fill this gap, we first describe the nature and time course of structural changes in the nucleosomes -2, -1, and +1 of the murine Egr1 gene upon induction. To initiate the transient activation of the gene, we used the stimulation of MLP29 cells with phorbol esters and the in vivo activation after partial hepatectomy. In both models, nucleosomes -1 and +1 are partially evicted, whereas nucleosomes +1 and -2 slide downstream durin…
Improving the Techniques for Human Hepatocyte Transplantation: Report from a Consensus Meeting in London
2012
On September 6 and 7, 2009 a meeting was held in London to identify and discuss what are perceived to be current roadblocks to effective hepatocyte transplantation as it is currently practiced in the clinics and, where possible, to offer suggestions to overcome the blocks and improve the outcomes for this cellular therapy. Present were representatives of most of the active clinical hepatocyte transplant programs along with other scientists who have contributed substantial basic research to this field. Over the 2-day sessions based on the experience of the participants, numerous roadblocks or challenges were identified, including the source of cells for the transplants and problems with tra…
p38 MAPK: A dual role in hepatocyte proliferation through reactive oxygen species
2013
p38 MAPKs are important mediators of signal transduction that respond to a wide range of extracellular stressors such as UV radiation, osmotic shock, hypoxia, pro-inflammatory cytokines, and oxidative stress. The most abundant family member is p38α, which helps to couple cell proliferation and growth in response to certain damaging stimuli. In fact, increased proliferation and impaired differentiation are hallmarks of p38α-deficient cells. It has been reported that reactive oxygen species (ROS) play a critical role in cytokine-induced p38α activation. Under physiological conditions, p38α can function as a mediator of ROS signaling and either activate or suppress cell cycle progression depen…
Management of liver failure: from transplantation to cell-based therapy
2011
The severe shortage of deceased donor organs has driven a search for alternative methods of treating liver failure. In this context, cell-based regenerative medicine is emerging as a promising interdisciplinary field of tissue repair and restoration, able to contribute to improving health in a minimally invasive fashion. Several cell types have allowed long-term survival in experimental models of liver injury, but their therapeutic potential in humans should be regarded with deep caution, because few clinical trials are currently available and the number of patients enrolled so far is too small to assess benefits versus risks. This review summarizes the current literature on the physiologi…
Beta-2-glycoprotein I is growth regulated and plays a role as survival factor for hepatocytes
2004
Beta-2-glycoprotein I (beta(2)GPI) is mainly produced by the liver and is found in plasma partially associated to lipoproteins. Although various properties have been attributed to this protein, its physiological role remains still unclear. We investigated its expression in cultured liver cells and in regenerating liver. Expression studies in HepG2 cells demonstrate that beta(2)GPI mRNA is regulated in a cell cycle-dependent manner, with very low expression in low cycling conditions and increasing levels in proliferating cells. p21 WAF-dependent growth arrest, induced by butyrate treatment, down-regulate beta(2)GPI mRNA levels. Immunolocalization in normal rat liver shows a non-homogeneous p…
Formation of Venous Collaterals and Regeneration in the Donor Remnant Liver: Volumetric Analysis and Three-Dimensional Visualization
2009
Abstract Purpose We sought was to quantify and visualize the regeneration of the remnant liver after living donor liver transplantation using computed tomographic (CT) data. Methods For the evaluation of preoperative and follow-up data, we developed a software assistant that was able to compute the volume growth of the remnant liver and liver territories as well as visualize the individual growth of hepatic vessels over time. The software was applied to CT data of 20 donors who underwent right hepatectomy including the middle hepatic vein with at least 3 follow-up examinations in the first year after transplantation. Results After donation of a right lobe graft, the remnant liver regenerate…
Hepatocyte growth factor induces MAT2A expression and histone acetylation in rat hepatocytes: role in liver regeneration 1
2001
SPECIFIC AIMSWe have studied the molecular mechanisms and mediators behind the induction of methionine adenosyltransferase 2 A (MAT2A) gene expression in the regenerating rat liver after partial he...