scholarly journals Constitutive and inducible profile of glutathione S-transferase subunits in biliary epithelial cells and hepatocytes isolated from rat liver

1993 ◽  
Vol 291 (2) ◽  
pp. 641-647 ◽  
Author(s):  
M Parola ◽  
M E Biocca ◽  
G Leonarduzzi ◽  
E Albano ◽  
M U Dianzani ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Rat Liver ◽  
Cell Types ◽  
Glutathione S Transferase ◽  
Biliary Epithelial Cells ◽  
Cytosolic Glutathione ◽  
Fold Induction ◽  
Quantitative Manner ◽  
Parenchymal Cells ◽  
First Time

The constitutive and inducible cytosolic glutathione S-transferase (EC 2.5.1.18) subunit compositions of parenchymal cells (hepatocytes) and biliary epithelial cells (BEC) from rat liver have been quantitatively analysed using reverse-phase h.p.l.c. Hepatocytes, analysed in the absence of non-parenchymal cells, expressed constitutively the following subunits, in order of their concentration: 3, 4, 2, 1a, 1b, 8, 6 and 10. BEC express constitutively only four of the GST subunits expressed by hepatocytes and these are, in order of their concentration: subunits 2, 7, 4 and 3. Notable differences from hepatocytes are that BEC completely lack the Alpha-class subunits 1a and 1b that are major subunits in hepatocytes, Mu-class subunits make up a very low proportion of the total, and the Pi-class subunit 7 is a major subunit in BEC, whereas it is essentially absent from hepatocytes. For the first time, the effects of the inducing agents phenobarbitone (PB), beta-naphthoflavone (beta-NF) and ethoxyquin (EQ) have been characterized in a comprehensive and quantitative manner in both cell types. PB, beta-NF and EQ increased total GST protein in hepatocytes by approx. 2-fold, 3-fold and 4-fold respectively. Subunits significantly induced in hepatocytes were (in order of fold-induction): by PB, 1b > 8 > 3 > 2 > 4; by beta-NF, 1b > 8 > 2 > 3 > 4; and by EQ, 7 > 1b > 10 > 8 > 3 > 2 > 1a > 4. In BEC, neither PB nor beta-NF had significant effects on the total amount of GST protein, although PB did significantly induce subunit 3 at the expense of other subunits. EQ increased total GST protein nearly 5-fold in BEC, subunits 7 and 3 being induced dramatically above constitutive levels.

scholarly journals The distribution, induction and isoenzyme profile of glutathione S-transferase and glutathione peroxidase in isolated rat liver parenchymal, Kupffer and endothelial cells

1989 ◽  
Vol 264 (3) ◽  
pp. 737-744 ◽  
Author(s):  
P Steinberg ◽  
H Schramm ◽  
L Schladt ◽  
L W Robertson ◽  
H Thomas ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Glutathione Peroxidase ◽  
Rat Liver ◽  
Peroxidase Activity ◽  
Cell Types ◽  
Transferase Activity ◽  
Glutathione Peroxidase Activity ◽  
Glutathione S Transferase ◽  
Liver Parenchymal ◽  
Parenchymal Cells

The distribution and inducibility of cytosolic glutathione S-transferase (EC 2.5.1.18) and glutathione peroxidase (EC 1.11.1.19) activities in rat liver parenchymal, Kupffer and endothelial cells were studied. In untreated rats glutathione S-transferase activity with 1-chloro-2,4-dinitrobenzene and 4-hydroxynon-2-trans-enal as substrates was 1.7-2.2-fold higher in parenchymal cells than in Kupffer and endothelial cells, whereas total, selenium-dependent and non-selenium-dependent glutathione peroxidase activities were similar in all three cell types. Glutathione S-transferase isoenzymes in parenchymal and non-parenchymal cells isolated from untreated rats were separated by chromatofocusing in an f.p.l.c. system: all glutathione S-transferase isoenzymes observed in the sinusoidal lining cells were also detected in the parenchymal cells, whereas Kupffer and endothelial cells lacked several glutathione S-transferase isoenzymes present in parenchymal cells. At 5 days after administration of Arocolor 1254 glutathione S-transferase activity was only enhanced in parenchymal cells; furthermore, selenium-dependent glutathione peroxidase activity decreased in parenchymal and non-parenchymal cells. At 13 days after a single injection of Aroclor 1254 a strong induction of glutathione S-transferase had taken place in all three cell types, whereas selenium-dependent glutathione peroxidase activity remained unchanged (endothelial cells) or was depressed (parenchymal and Kupffer cells). Hence these results clearly establish that glutathione S-transferase and glutathione peroxidase are differentially regulated in rat liver parenchymal as well as non-parenchymal cells. The presence of glutathione peroxidase and several glutathione S-transferase isoenzymes capable of detoxifying a variety of compounds in Kupffer and endothelial cells might be crucial to protect the liver from damage by potentially hepatotoxic substances.

Glutathione S-transferase in chemotherapy resistance and in carcinogenesis

1992 ◽  
Vol 70 (5) ◽  
pp. 349-353 ◽  
Author(s):  
Robyn L. Schecter ◽  
Moulay A. Alaoui-Jamali ◽  
Gerald Batist
Keyword(s):  
Rat Liver ◽  
Alkylating Agents ◽  
Chemotherapy Resistance ◽  
Gene Families ◽  
Cell Types ◽  
Environmental Chemicals ◽  
Glutathione S Transferase ◽  
Cytosolic Glutathione ◽  
Glutathione S Transferases ◽  
Relationship Of

Cytosolic glutathione S-transferases are composed of two monomeric subunits. These monomers are the products of different gene families designated alpha, mu, and pi. Dimerization yields either homodimeric or heterodimeric holoenzymes within the same family. The members of this complex group of proteins have been linked to the detoxification of environmental chemicals and carcinogens, and have been shown to be overexpressed in normal and tumor cells following exposure to cytotoxic drugs. They also are overexpressed in carcinogen-induced rat liver preneoplastic nodules in rat liver. In all of these cases, the changes in exprssion of glutathione S-transferases are paralleled by increased resistance to cytotoxic chemicals. The degree of resistance is related to the substrate specificity of the isozyme. The relationship of the glutathione S-transferase genes to drug resistance has been directly demonstrated by gene transfer studies, where cDNAs encoding the various subunits of glutathione S-transferase have been transfected into a variety of cell types. This review discusses the results of numerous studies that associate resistance to alkylating agents with overexpression of protective detoxifying glutathione S-transferase enzymes.Key words: glutathione S-transferase, chemotherapy, carcinogenesis, alkylating agents, DNA damage.

scholarly journals The variation with age of the structure of chromatin in three cell types from rat liver

1979 ◽  
Vol 179 (2) ◽  
pp. 291-298 ◽  
Author(s):  
V Zongza ◽  
A P Mathias
Keyword(s):  
Rat Liver ◽  
Cell Types ◽  
Repeat Length ◽  
Micrococcal Nuclease ◽  
Dna Repeat ◽  
Old Rats ◽  
Parenchymal Cells ◽  
Kinetics Of

The organization of chromatin in three rat liver nuclear populations, namely diploid stromal, diploid parenchymal, and tetraploid parenchymal nuclei, which were separated by zonal centrifugation, was studied by digestion with micrococcal nuclease and pancreatic deoxyribonuclease in 3-week-old rats in which the parenchymal cells contain diploid nuclei and in 2-and 4-month-old rats with a high proportion of tetraploid nuclei. Digestion by micrococcal nuclease allowed the estimation of DNA-repeat length in chromatin. Parenchymal nuclei have shorter repeat length than stromal nuclei and DNA-repeat length increases with the age in all three nuclei populations. The kinetics of digestion by micrococcal nuclease showed that nuclei with shorter repeat length are more sensitive to micrococcal nuclease and that the sensitivity of chromatin decreases with age for all the types of nuclei in this study. The kinetics of digestion by pancreatic deoxyribonuclease showed that sensitivity of chromatin is related to the repeat length and that the sensitivity decreases with the ages.

scholarly journals Induction of glutathione S-transferase P-form in primary cultured rat liver parenchymal cells by co-planar polychlorinated biphenyl congeners

1992 ◽  
Vol 281 (2) ◽  
pp. 539-543 ◽  
Author(s):  
Y Aoki ◽  
K Satoh ◽  
K Sato ◽  
K T Suzuki
Keyword(s):  
Protein Synthesis ◽  
Rat Liver ◽  
Polychlorinated Biphenyl ◽  
Glutathione S Transferase ◽  
Liver Parenchymal ◽  
Pcb Congeners ◽  
Parenchymal Cells

Alterations in protein synthesis in primary cultured rat liver parenchymal cells were examined after their exposure to the potent carcinogens, polychlorinated biphenyl (PCB) congeners. Co-planar PCB congeners (3,4,5,3′,4′-PCB and 3,4,5,3′,4′,5′-PCB) (10 nM) induced a protein, the Mr of which was 25,000 (25 k protein) under denaturing conditions. However, non-co-planar PCB congeners and several xenobiotics, which induce microsomal proteins, did not induce the 25 k protein. By using immunoblotting, the 25 k protein was identified as glutathione S-transferase P-form (GST-P, 7-7, EC 2.5.1.18).

Ultrastructure of the Celis of a Fish Tastebud

1976 ◽  
Vol 34 ◽  
pp. 128-129
Author(s):  
Gary E. Korte
Keyword(s):  
T Cells ◽  
Epithelial Cells ◽  
Basement Membrane ◽  
B Cell ◽  
Cell Types ◽  
Afferent Nerve ◽  
The Other ◽  
Nerve Plexus ◽  
The Subject ◽  
First Time

Four types of specialized epithelial cells have been observed in the fish tastebud, within the capsule formed by the flattened epidermal cells. However, only two or three of these have been previously noted in any one species, including the glass catfish Kryptopterus bicirrhis, the subject of this investigation (1,2). For the first time, all four types of specialized cells have been observed,and an artifact of fixation relevant to the identification of these cell types has been uncovered.A single basal, or B cell lies on the basement membrane of the epidermis (Fig. 1). It makes many synapses with the afferent nerve plexus, which lies just above it. The other three cell types, designated S,L and T cells (Fig. 2A) are external to the nerve plexus, and only rarely make synapses onto nerves, confirming the observations of several other investigations.

scholarly journals Identification of an enhancer element of class Pi glutathione S-transferase gene required for expression by a co-planar polychlorinated biphenyl

1999 ◽  
Vol 338 (3) ◽  
pp. 599-605 ◽  
Author(s):  
Michi MATSUMOTO ◽  
Masayoshi IMAGAWA ◽  
Yasunobu AOKI
Keyword(s):  
Rat Liver ◽  
Polychlorinated Biphenyl ◽  
Signal Transduction Pathway ◽  
Flanking Sequence ◽  
Glutathione S Transferase ◽  
Enhancer Element ◽  
Liver Parenchymal ◽  
Gstp1 Gene ◽  
Responsive Element ◽  
Parenchymal Cells

3,3´,4,4´,5-Pentachlorobiphenyl (PenCB), one of the most toxic co-planar polychlorinated biphenyl congeners, specifically induces class Pi glutathione S-transferase (GSTP1) as well as cytochrome P-450 1A1 in primary cultured rat liver parenchymal cells [Aoki, Matsumoto and Suzuki (1993) FEBS Lett. 333, 114–118]. However, the 5´-flanking sequence of the GSTP1 gene does not contain a xenobiotic responsive element, to which arylhydrocarbon receptor binds. Using a chloramphenicol acetyltransferase assay we demonstrate here that the enhancer termed GSTP1 enhancer I (GPEI) is necessary for the stimulation by PenCB of GSTP1 gene expression in primary cultured rat liver parenchymal cells. GPEI is already known to contain a dyad of PMA responsive element-like elements oriented palindromically. It is suggested that a novel signal transduction pathway activated by PenCB contributes to the stimulation of GSTP1 expression.

scholarly journals Immunocytochemical studies on the localization of plasma and of cellular retinol-binding proteins and of transthyretin (prealbumin) in rat liver and kidney.

1984 ◽  
Vol 98 (5) ◽  
pp. 1696-1704 ◽  
Author(s):  
M Kato ◽  
K Kato ◽  
D S Goodman
Keyword(s):  
Rat Liver ◽  
Binding Protein ◽  
Cell Types ◽  
Retinol Binding Protein ◽  
Specific Staining ◽  
Intense Staining ◽  
Cytoplasmic Staining ◽  
Liver And Kidney ◽  
Diffuse Cytoplasmic Staining ◽  
Parenchymal Cells

The immunocytochemical localization of cellular retinol-binding protein (CRBP), of plasma retinol-binding protein (RBP), and of plasma transthyretin (TTR) was studied in rat liver and kidney. The studies employed normal rats, retinol-deficient rats, and rats fed excess retinol. Antisera were prepared in rabbits against purified rat CRBP, RBP, and TTR. The primary antibodies and goat anti-rabbit IgG were purified by immunosorbent affinity chromatography, using the respective pure antigen coupled to Sepharose as the immunosorbent. This procedure effectively removed cross-reactive and heterophile antibodies, which permitted the specific staining and localization of each antigen by the unlabeled peroxidase-antiperoxidase method. CRBP was found to be localized in two cell types in the liver, the parenchymal cells and the fat-storing cells. Diffuse cytoplasmic staining for CRBP was seen in all the parenchymal cells. Much more intense staining for CRBP was seen in the fat-storing cells. The prominence of the CRBP-positive fat-storing cells changed markedly with vitamin A status. Thus, these cells were most prominent, and appeared most numerous, in liver from rats fed excess retinol. Both RBP and TTR were localized within liver parenchymal cells. The intensity of RBP staining increased markedly in retinol-deficient rat liver, consistent with previous biochemical observations. With the methods employed, specific staining for RBP or TTR was not seen in cells other than the parenchymal cells. In the kidney, all three proteins (CRBP, RBP, and TTR) were localized in the proximal convoluted tubules of the renal cortex. Staining for RBP was much more intense in normal kidney than in kidney from retinol-deficient rats. These findings reflect the fact that RBP in the tubules represents filtered and reabsorbed RBP. The pattern of specific staining for CRBP among the various tubules was very similar to that seen for RBP on adjacent, serial sections of kidney. The function of CRBP in the kidney is not known.

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