Interactions of deoxynivalenol and lipopolysaccharides on cytokine excretion and mRNA expression in porcine hepatocytes and Kupffer cell enriched hepatocyte cultures

P-Glycoprotein transporters encoded by mdr1 (multidrug resistance) genes mediate extrusion of an array of lipophilic xenobiotics from the cell. In rat liver, mdr transcripts have been shown to be expressed mainly in hepatocytes of the periportal region. Since gradients in oxygen tension (pO2) may contribute towards zonated gene expression, the influence of arterial and venous pO2 on mRNA expression of the mdr1b isoform was examined in primary rat hepatocytes cultured for up to 3 days. Maximal mdr1b mRNA levels (100%) were observed under arterial pO2 after 72h, whereas less than half-maximal mRNA levels (40%) were attained under venous pO2. Accordingly, expression of mdr protein and extrusion of the mdr1 substrate rhodamine 123 were maximal under arterial pO2 and reduced under venous pO2. Oxygen-dependent modulation of mdr1b mRNA expression was prevented by actinomycin D, indicating transcriptional regulation. Inhibition of haem synthesis by 25µM CoCl2 blocked mdr1b mRNA expression under both oxygen tensions, whereas 80µM desferrioxamine abolished modulation by O2. Haem (10µM) increased mdr1b mRNA levels under arterial and venous pO2. In hepatocytes treated with 50µM H2O2, mdr1b mRNA expression was elevated by about 1.6-fold at venous pO2 and 1.5-fold at arterial pO2. These results support the conclusion that haem proteins are crucial for modulation of mdr1b mRNA expression by O2 in hepatocyte cultures and that reactive oxygen species may participate in O2-dependent signal transduction. Furthermore, the present study suggests that oxygen might be a critical modulator for zonated secretion of mdr1 substrates into the bile.

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Hormonal control of insulin-like growth factor-I and growth hormone receptor mRNA expression by porcine hepatocytes in culture

Journal of Endocrinology ◽

10.1677/joe.0.1460239 ◽

1995 ◽

Vol 146 (2) ◽

pp. 239-245 ◽

Cited By ~ 25

Author(s):

J M Brameld ◽

P A Weller ◽

J C Saunders ◽

P J Buttery ◽

R S Gilmour

Keyword(s):

Growth Factor ◽

Thyroid Hormones ◽

Mrna Expression ◽

Culture Medium ◽

Insulin Like Growth Factor ◽

Factor I ◽

Igf I ◽

Class 1 ◽

Growth Factor I ◽

Porcine Hepatocytes

Abstract The effects of various hormones commonly added to hepatocyte culture media upon the expression of the GH receptor (GHR) and insulin-like growth factor-I (IGF-I) genes in cultured porcine hepatocytes were investigated. Preliminary investigations indicated that there was an absolute requirement only for insulin, with high losses of cell viability upon long term exclusion of insulin from the culture medium. The decline in GHR expression with time in culture was found to be less when high levels of glucose were included in the medium. Therefore the basal culture medium used in these studies was Williams' medium E supplemented with 0·2% (w/v) BSA, 5000 mg glucose/l and 100 nmol porcine insulin/l. The addition of dexamethasone (100 nmol/l) increased the expression of both GHR and IGF-I (class 1 transcripts only) mRNA (P<0·001 and P<0·05 respectively), and resulted in an increased responsiveness of IGF-I mRNA expression to GH (1 μg/ml), when the two were added in combination (although only class 1 transcripts were shown to be statistically significant, P<0·01). The addition of either thyroid hormone (1 nmol/l T3 or T4) alone also increased the expression of GHR mRNA (P<0·01) in addition to the dexamethasone stimulated expression, with T4 appearing to decrease IGF-I expression slightly (P<0·05) (either on its own or with T3). As with dexamethasone, the thyroid hormones increased the response of IGF-I mRNA expression to GH (1 μg/ml) when added in combination with GH (P<0·001). These observations demonstrate one possible mechanism for the interactions of glucocorticoids and thyroid hormones with the GH–IGF axis. Journal of Endocrinology (1995) 146, 239–245

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Regulation of Heme Oxygenase-1 Gene Expression by Anoxia and Reoxygenation in Primary Rat Hepatocyte Cultures

Experimental Biology and Medicine ◽

10.1177/15353702-0322805-51 ◽

2003 ◽

Vol 228 (5) ◽

pp. 584-589 ◽

Cited By ~ 15

Author(s):

Andreas Ohlmann ◽

Susanne Giffhorn-Katz ◽

Ivonne Becker ◽

Norbert Katz ◽

Stephan Immenschuh

Keyword(s):

Gene Expression ◽

Mrna Expression ◽

Heme Oxygenase ◽

Heme Oxygenase 1 ◽

Protein Synthesis Inhibitor ◽

Mrna Levels ◽

Rat Hepatocyte ◽

Hsp70 Mrna ◽

Hepatocyte Cultures ◽

Antioxidant Agents

Heme oxygenase (HO) catalyzes the rate-limiting enzymatic step of heme degradation and regulates the cellular heme content. Gene expression of the inducible isoform of HO, HO-1, is upregulated in response to various oxidative stress stimuli. To investigate the regulatory role of anoxia and reoxygenation (A/R) on hepatic HO-1 gene expression, primary cultures of rat hepatocytes were exposed after an anoxia of 4 hr to normal oxygen tension for various lengths of time. For comparison, gene expression of the noninducible HO isoform, HO-2, and that of the heat-shock protein 70 (HSP70) were determined. During reoxygenation, a marked increase of HO-1 and HSP70 steady-state mRNA levels was observed, whereas no alteration of HO-2 mRNA levels occurred. Corresponding to HO-1 mRNA, an increase of HO-1 protein expression was determined by Western blot analysis. The anoxia-dependent induction of HO-1 was prevented by pretreatment with the transcription inhibitor, actinomycin D, but not by the protein synthesis inhibitor, cycloheximide, suggesting a transcriptional regulatory mechanism. After exposure of hepatocytes to anoxia, the relative levels of oxidized glutathione increased within the first 40 min of reoxygenation. Pretreament of cell cultures with the antioxidant agents, β-carotene and allopurinol, before exposure to A/R led to a marked decrease of HO-1 and HSP70 mRNA expression during reoxygenation. An even more pronounced reduction of mRNA expression was observed after exposure to desferrioxamine. Taken together, the data demonstrate that HO-1 gene expression in rat hepatocyte cultures after A/R is upregulated by a transcriptional mechanism that may be, in part, mediated via the generation of ROS and the glutathione system.

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Kupffer cell-derived cytokines induce the synthesis of a leukocyte chemotactic peptide, interleukin-8, in human hepatoma and primary hepatocyte cultures

Hepatology ◽

10.1016/0270-9139(91)90137-k ◽

1991 ◽

Vol 14 (6) ◽

pp. 1112-1122 ◽

Cited By ~ 8

Author(s):

A Thornton

Keyword(s):

Kupffer Cell ◽

Interleukin 8 ◽

Primary Hepatocyte ◽

Human Hepatoma ◽

Chemotactic Peptide ◽

Hepatocyte Cultures ◽

Primary Hepatocyte Cultures

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Dominant Negative Effect of TGF-β1 and TNF-α on Basal and IL-6–Induced Lipoprotein(a) and Apolipoprotein(a) mRNA Expression in Primary Monkey Hepatocyte Cultures

Arteriosclerosis Thrombosis and Vascular Biology ◽

10.1161/01.atv.18.6.984 ◽

1998 ◽

Vol 18 (6) ◽

pp. 984-990 ◽

Cited By ~ 52

Author(s):

Randy Ramharack ◽

Derek Barkalow ◽

Mark A. Spahr

Keyword(s):

Mrna Expression ◽

Dominant Negative ◽

Dominant Negative Effect ◽

Lipoprotein A ◽

Hepatocyte Cultures ◽

Apolipoprotein A ◽

Tnf Α ◽

Negative Effect ◽

Tgf Β1

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S-allyl-glutathione improves experimental liver fibrosis by regulating Kupffer cell activation in rats

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.00023.2017 ◽

2018 ◽

Vol 314 (2) ◽

pp. G150-G163 ◽

Cited By ~ 7

Author(s):

Shigekazu Takemura ◽

Hideki Azuma ◽

Mayuko Osada-Oka ◽

Shoji Kubo ◽

Toshihiko Shibata ◽

...

Keyword(s):

Heat Shock ◽

Liver Fibrosis ◽

Heat Shock Protein ◽

Mrna Expression ◽

Primary Culture ◽

Kupffer Cell ◽

Hepatic Stellate Cells ◽

Stellate Cells ◽

Diallyl Sulfide ◽

M2 Phenotype

S-allyl-glutathione (SAG) is one of the metabolites of diallyl sulfide (DAS), a component of garlic. DAS has shown preventative effects on carcinogenesis in animal models. However, whether synthetic SAG can improve liver fibrosis has not been investigated. We examined the potential preventive effects of SAG on acute and chronic models of liver fibrosis by chronic carbon tetrachloride (CCl4) administration. SAG inhibited liver fibrogenesis induced by CCl4 in a dose-dependent manner and reduced heat shock protein-47 (HSP47), a collagen-specific chaperone, and other fibrosis markers. In fibrosis regression models, after administration of either CCl4 for 9 wk or dimethyl nitrosamine (DMN) for 6 wk, SAG markedly accelerated fibrolysis in both models. In the regression stage of DMN-treated liver, SAG normalized the ratio of M2 phenotype (expression of mannose receptor) in Kupffer cells (KCs). Consistent with these results, the culture supernatants of SAG-treated M2-phenotype KCs inhibited collagen-α1(I) chain (COL1A1) mRNA expression in primary culture-activated rat hepatic stellate cells (HSCs). However, SAG did not directly inhibit HSC activation. In an acute model of CCl4 single injection, SAG inhibited hepatic injury dose dependently consistent with the inhibited the elevation of the bilirubin and ALT levels. These findings suggest that SAG could improve the fibrogenic and fibrolysis cascade via the regulation of excess activated and polarized KCs. SAG may also serve as a preventive and therapeutic agent in fibrosis of other organs for which current clinical therapy is unavailable. NEW & NOTEWORTHY S-allyl-glutathione (SAG) is a metabolite of diallyl sulfide, a component of garlic. SAG increased hepatic glutathione levels and GSH-to-GSSG ratio in normal rats. SAG treatment before or after liver fibrosis from chronic CCl4 administration improved liver fibrosis and regression. SAG decreased heat shock protein-47 (HSP47), a collagen-specific chaperone, and other fibrosis markers in CCl4-treated livers. SAG-treated Kupffer cell conditioned medium also inhibited collagen-α1(I) chain (COL1A1) mRNA expression and other markers in primary culture hepatic stellate cells.

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