The control of DNA synthesis in primary cultures of hepatocytes from adult and young rats: Interactions of extracellular matrix components, epidermal growth factor, and the cell cycle

Tomomura, Akito; Sawada, Norimasa; Sattler, Gerald L.; Kleinman, Hynda K.; Pitot, Henry C.

doi:10.1002/jcp.1041300208

Cited by 61 publications

(26 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…EGF effectively stimulated DNA synthesis in the primary cultures of hepatocytes at the low cell density (4 • 104 cells/cm2), showing the maximal effect at a concentration of 10 ng/ml, as reported by others [20] (Table 1). Therefore, in the following experiments, EGF was added to the cultures at an optimal concentration of 10 ng/ml.…”

Section: Resultssupporting

confidence: 67%

Enhancing effect of S-(1,2-dicarboxyethyl)glutathione on epidermal growth factor-stimulated DNA synthesis in primary cultures of adult rat hepatocytes

et al. 1990

View full text Add to dashboard Cite

A tripeptide S-(1,2-dicarboxyethyl)glutathione (DCE-GS) has been reported to be present in the lens, liver, and heart. Effects of DCE-GS and its derivatives and analogues on hepatocyte deoxyribonucleic acid (DNA) synthesis were examined using primary cultures of adult-rat hepatocytes. DCE-GS alone had no effect on DNA synthesis of hepatocytes. However, when DCE-GS was added with epidermal growth factor (EGF), the tripeptide effectively enhanced EGF-stimulated DNA synthesis of hepatocytes under the culture conditions of low cell density, but not high cell density. On the other hand, some esters and amides of DCE-GS and DCE-GS analogues showed a suppressive effect on DNA synthesis of hepatocytes in the absence of EGF. The derivatives and analogues together with EGF had no effect or rather a suppressive effect on stimulation of hepatocyte DNA synthesis by EGF. Therefore, the two carboxy groups in the substituent probably play an important role in the stimulative activity of DCE-GS. In addition, it seems likely that one of in vivo physiological roles of DCE-GS is related to liver regeneration.

show abstract

Section: Resultssupporting

confidence: 67%

Enhancing effect of S-(1,2-dicarboxyethyl)glutathione on epidermal growth factor-stimulated DNA synthesis in primary cultures of adult rat hepatocytes

et al. 1990

View full text Add to dashboard Cite

show abstract

“…Several reports have shown an ECM-dependent phenotype of hepatocytes in vitro and an effect of different ECM-molecules on gene expression in hepatocytes. [48][49][50][51][52][53][54][55] The signal transduction of ECM molecules controlling gene expression in hepatocytes are not well understood. Only recently Mooney et al 56 have shown that inhibition as well as support of hepatocyte cell extension by ECM molecules is involved in this regulation.…”

Section: Discussionmentioning

confidence: 99%

Differential regulation of extracellular matrix synthesis during liver regeneration after partial hepatectomy in rats

et al. 1999

View full text Add to dashboard Cite

Little is known about the modulation of the extracellular matrix (ECM) during liver regeneration. We studied the temporospatial expression of procollagens and of matrix metalloproteinases (MMPs) and their physiological antagonists, the tissue inhibitors of metalloproteinases (TIMPs) after two-thirds partial hepatectomy (PH) by Northern blot analysis and in situ hybridization. The entry of hepatocytes into the S-phase at 24 hours after PH was accompanied by a peak (sixfold induction) of hepatic TIMP-1 RNA levels that steadily declined thereafter to reach normal levels 144 hours after PH. Moderate MMP-2 and TIMP-2 RNA levels remained constant up to 144 hours after PH, and MMP-1 and -13 RNA were always undetectable. In situ hybridization showed a dramatic upregulation of TIMP-1 RNA transcripts in mesenchymal cells of portal, perisinusoidal and, to a lesser extent, pericentral areas. In contrast, scattered hepatocytes represented only a minor fraction (below 10%) of TIMP-1 RNA positive cells. When hepatocytes stopped DNA synthesis at 72 hours after PH, an upregulation of procollagen ␣1(I) and ␣2(III) transcripts was observed paralleled by threefold increased PIIINP levels in the sera. Our data reveal a tightly regulated program of de novo matrix synthesis after PH. Whereas interstitial procollagens appear to participate in the induction and maintenance of the quiescent hepatocyte phenotype, the early and localized expression of TIMP-1 indicates a role unrelated to its function as a general MMP-antagonist, e.g., as a growth promoting agent for hepatocytes. (HEPATOL-OGY 1999;30:1159-1166.)The liver can restore tissue loss by regeneration. This capacity is of physiological relevance in numerous liver diseases such as viral and alcoholic hepatitis, metabolic disorders, or after liver surgery. One of the best-studied animal models of liver regeneration is two-thirds partial hepatectomy (PH), which was originally described by Higgins and Anderson. 1 In this model hepatocytes enter the cell cycle in a controlled process. DNA-synthesis starts 12 to 16 hours after hepatectomy and peaks at 24 to 48 hours. The onset of mitosis follows 6 to 8 hours later reaching its maximum 48 hours after surgery. Three days after PH, the original organ-mass is almost restored. 2,3 However, at this stage of liver regeneration hepatic histology differs substantially from normal. Hepatocytes are grouped into nonvascularized clusters of 12 to 15 cells, and the amount of extracellular matrix is clearly reduced as a consequence of hepatocyte proliferation without concomitant ECM-synthesis. 4 After this time point, hepatocyte proliferation decreases and stellate cells migrate into the clusters. At the same time, new vascular branches are formed. Finally, normal liver histology is reestablished 8 to 10 days after surgery.During liver regeneration, the synthesis of extracellular matrix (ECM) might play an important role in re-establishing the quiescent and differentiated phenotype of hepatocytes. Several in vitro studies showed that the extracellular ...

show abstract

“…This includes insulin and glucagon, 32 somatostatin, 33 epidermal growth factor (EGF), 34 and hepatocyte growth factor (HGF). 35 The stimulatory effects of these factors on DNA synthesis, for example, are diverse: EGF 36 and HGF 12 upregulated hepatocyte DNA synthesis. Insulin acted as a co-mitogen, 37 whereas somatostatin acted as an inhibitor.…”

Section: How To Explain the Effects In Our Hepatocyte-hlet Co-cultures?mentioning

confidence: 99%

Influence of Pancreatic Islets on Growth and Differentiation of Hepatocytes in Co-Culture

Kaufmann¹,

Fiegel²,

Kneser³

et al. 1999

Tissue Engineering

View full text Add to dashboard Cite

Improvement of cell culture conditions in hepatic tissue engineering may permit cell/tissue banking and the generation of liver tissue equivalents for transplantation. In these systems, continuous hepatotrophic stimulation is still necessary. We investigated the stimulatory effects of pancreatic islets on hepatocytes in co-culture and characterized the stimulatory mechanisms. Hepatocytes and pancreatic islets were harvested from Lewis rats. Cells were cultured on collagen dishes either with nonstimulated media (controls and co-cultures with low or high islet rate) or stimulated media (controls and co-cultures). To characterize stimulatory mechanisms, additional co-cultures with membrane separation, with antiinsulin, antiglucagon, and with both antibodies were examined. Hepatocyte numbers, albumin secretion rate by enzyme-linked immunoadsorbent assay, and monoethylglycinxylidid biotransformation values by fluorescence polarization immunoassay were assessed. A radioimmunoassay measured insulin and glucagon concentrations. In groups with nonstimulated media, cell number was higher in co-cultures with low islet rate, and albumin secretion rate was increased in co-cultures with high islet rate compared to controls. MEGX biotransformation was decreased in co-cultures. In groups with stimulated media, co-culture had no impact on cell number or albumin secretion rate. Hepatocyte numbers and albumin secretion rates were not changed in co-cultures after membrane separation. Islet effects on hepatocytes were reduced in co-cultures with antiinsulin, antiglucagon, or both antibodies. Pancreatic islets provide stimulation for hepatocytes in vitro. Islet effects were mediated by soluble factors, and are dependent on insulin and glucagon. These results permit further investigations towards three-dimensional transplantable hepatocyte-islet devices for continuous in vitro and in vivo stimulation.

show abstract

The control of DNA synthesis in primary cultures of hepatocytes from adult and young rats: Interactions of extracellular matrix components, epidermal growth factor, and the cell cycle

Cited by 61 publications

References 38 publications

Enhancing effect of S-(1,2-dicarboxyethyl)glutathione on epidermal growth factor-stimulated DNA synthesis in primary cultures of adult rat hepatocytes

Enhancing effect of S-(1,2-dicarboxyethyl)glutathione on epidermal growth factor-stimulated DNA synthesis in primary cultures of adult rat hepatocytes

Differential regulation of extracellular matrix synthesis during liver regeneration after partial hepatectomy in rats

Influence of Pancreatic Islets on Growth and Differentiation of Hepatocytes in Co-Culture

Contact Info

Product

Resources

About