Limits...
Recent advances in 2D and 3D in vitro systems using primary hepatocytes, alternative hepatocyte sources and non-parenchymal liver cells and their use in investigating mechanisms of hepatotoxicity, cell signaling and ADME.

Godoy P, Hewitt NJ, Albrecht U, Andersen ME, Ansari N, Bhattacharya S, Bode JG, Bolleyn J, Borner C, Böttger J, Braeuning A, Budinsky RA, Burkhardt B, Cameron NR, Camussi G, Cho CS, Choi YJ, Craig Rowlands J, Dahmen U, Damm G, Dirsch O, Donato MT, Dong J, Dooley S, Drasdo D, Eakins R, Ferreira KS, Fonsato V, Fraczek J, Gebhardt R, Gibson A, Glanemann M, Goldring CE, Gómez-Lechón MJ, Groothuis GM, Gustavsson L, Guyot C, Hallifax D, Hammad S, Hayward A, Häussinger D, Hellerbrand C, Hewitt P, Hoehme S, Holzhütter HG, Houston JB, Hrach J, Ito K, Jaeschke H, Keitel V, Kelm JM, Kevin Park B, Kordes C, Kullak-Ublick GA, LeCluyse EL, Lu P, Luebke-Wheeler J, Lutz A, Maltman DJ, Matz-Soja M, McMullen P, Merfort I, Messner S, Meyer C, Mwinyi J, Naisbitt DJ, Nussler AK, Olinga P, Pampaloni F, Pi J, Pluta L, Przyborski SA, Ramachandran A, Rogiers V, Rowe C, Schelcher C, Schmich K, Schwarz M, Singh B, Stelzer EH, Stieger B, Stöber R, Sugiyama Y, Tetta C, Thasler WE, Vanhaecke T, Vinken M, Weiss TS, Widera A, Woods CG, Xu JJ, Yarborough KM, Hengstler JG - Arch. Toxicol. (2013)

Bottom Line: When isolating liver cells, some pathways are activated, e.g., the RAS/MEK/ERK pathway, whereas others are silenced (e.g. HNF-4α), resulting in up- and downregulation of hundreds of genes.One key message is that despite our enthusiasm for in vitro systems, we must never lose sight of the in vivo situation.Although hepatocytes have been isolated for decades, the hunt for relevant alternative systems has only just begun.

View Article: PubMed Central - PubMed

Affiliation: Leibniz Research Centre for Working Environment and Human Factors (IFADO), 44139, Dortmund, Germany.

ABSTRACT
This review encompasses the most important advances in liver functions and hepatotoxicity and analyzes which mechanisms can be studied in vitro. In a complex architecture of nested, zonated lobules, the liver consists of approximately 80 % hepatocytes and 20 % non-parenchymal cells, the latter being involved in a secondary phase that may dramatically aggravate the initial damage. Hepatotoxicity, as well as hepatic metabolism, is controlled by a set of nuclear receptors (including PXR, CAR, HNF-4α, FXR, LXR, SHP, VDR and PPAR) and signaling pathways. When isolating liver cells, some pathways are activated, e.g., the RAS/MEK/ERK pathway, whereas others are silenced (e.g. HNF-4α), resulting in up- and downregulation of hundreds of genes. An understanding of these changes is crucial for a correct interpretation of in vitro data. The possibilities and limitations of the most useful liver in vitro systems are summarized, including three-dimensional culture techniques, co-cultures with non-parenchymal cells, hepatospheres, precision cut liver slices and the isolated perfused liver. Also discussed is how closely hepatoma, stem cell and iPS cell-derived hepatocyte-like-cells resemble real hepatocytes. Finally, a summary is given of the state of the art of liver in vitro and mathematical modeling systems that are currently used in the pharmaceutical industry with an emphasis on drug metabolism, prediction of clearance, drug interaction, transporter studies and hepatotoxicity. One key message is that despite our enthusiasm for in vitro systems, we must never lose sight of the in vivo situation. Although hepatocytes have been isolated for decades, the hunt for relevant alternative systems has only just begun.

Show MeSH

Related in: MedlinePlus

Lobular zonation of different metabolic pathways. The length and thickness of the colored fields represents the localization and activity gradients of individual metabolic pathways along the porto-central axis
© Copyright Policy - OpenAccess
Related In: Results  -  Collection


getmorefigures.php?uid=PMC3753504&req=5

Fig5: Lobular zonation of different metabolic pathways. The length and thickness of the colored fields represents the localization and activity gradients of individual metabolic pathways along the porto-central axis

Mentions: In the past, parenchymal heterogeneity has been extensively characterized with respect to the major metabolic pathways, namely carbohydrate, lipid, amino acid and drug metabolism. The most frequently used techniques for investigating the microdiversity of hepatocytes in liver parenchyma were immunocytochemistry or immunofluorescence and in situ hybridization which all provided a comprehensive overview about the exact lobular expression and localization of many enzymes of these metabolic pathways (reviewed by Meijer et al. 1990; Gebhardt 1992; Jungermann and Kietzmann 1996). For example, studies suggest that gluconeogenesis is present in all hepatocytes, but predominates in the periportal zone (Fig. 5). By contrast, glycolysis is most active in part of the pericentral zone, but generally shows a relatively low activity in hepatocytes. This distribution is dynamic and varies with feeding conditions. The zonation of other major metabolic pathways is schematically illustrated in Fig. 5. The immunochemical approach was also used for localizing hepatocytes involved in the synthesis of major serum proteins usually revealing shallow gradients in protein expression (Racine et al. 1995).Fig. 5


Recent advances in 2D and 3D in vitro systems using primary hepatocytes, alternative hepatocyte sources and non-parenchymal liver cells and their use in investigating mechanisms of hepatotoxicity, cell signaling and ADME.

Godoy P, Hewitt NJ, Albrecht U, Andersen ME, Ansari N, Bhattacharya S, Bode JG, Bolleyn J, Borner C, Böttger J, Braeuning A, Budinsky RA, Burkhardt B, Cameron NR, Camussi G, Cho CS, Choi YJ, Craig Rowlands J, Dahmen U, Damm G, Dirsch O, Donato MT, Dong J, Dooley S, Drasdo D, Eakins R, Ferreira KS, Fonsato V, Fraczek J, Gebhardt R, Gibson A, Glanemann M, Goldring CE, Gómez-Lechón MJ, Groothuis GM, Gustavsson L, Guyot C, Hallifax D, Hammad S, Hayward A, Häussinger D, Hellerbrand C, Hewitt P, Hoehme S, Holzhütter HG, Houston JB, Hrach J, Ito K, Jaeschke H, Keitel V, Kelm JM, Kevin Park B, Kordes C, Kullak-Ublick GA, LeCluyse EL, Lu P, Luebke-Wheeler J, Lutz A, Maltman DJ, Matz-Soja M, McMullen P, Merfort I, Messner S, Meyer C, Mwinyi J, Naisbitt DJ, Nussler AK, Olinga P, Pampaloni F, Pi J, Pluta L, Przyborski SA, Ramachandran A, Rogiers V, Rowe C, Schelcher C, Schmich K, Schwarz M, Singh B, Stelzer EH, Stieger B, Stöber R, Sugiyama Y, Tetta C, Thasler WE, Vanhaecke T, Vinken M, Weiss TS, Widera A, Woods CG, Xu JJ, Yarborough KM, Hengstler JG - Arch. Toxicol. (2013)

Lobular zonation of different metabolic pathways. The length and thickness of the colored fields represents the localization and activity gradients of individual metabolic pathways along the porto-central axis
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3753504&req=5

Fig5: Lobular zonation of different metabolic pathways. The length and thickness of the colored fields represents the localization and activity gradients of individual metabolic pathways along the porto-central axis
Mentions: In the past, parenchymal heterogeneity has been extensively characterized with respect to the major metabolic pathways, namely carbohydrate, lipid, amino acid and drug metabolism. The most frequently used techniques for investigating the microdiversity of hepatocytes in liver parenchyma were immunocytochemistry or immunofluorescence and in situ hybridization which all provided a comprehensive overview about the exact lobular expression and localization of many enzymes of these metabolic pathways (reviewed by Meijer et al. 1990; Gebhardt 1992; Jungermann and Kietzmann 1996). For example, studies suggest that gluconeogenesis is present in all hepatocytes, but predominates in the periportal zone (Fig. 5). By contrast, glycolysis is most active in part of the pericentral zone, but generally shows a relatively low activity in hepatocytes. This distribution is dynamic and varies with feeding conditions. The zonation of other major metabolic pathways is schematically illustrated in Fig. 5. The immunochemical approach was also used for localizing hepatocytes involved in the synthesis of major serum proteins usually revealing shallow gradients in protein expression (Racine et al. 1995).Fig. 5

Bottom Line: When isolating liver cells, some pathways are activated, e.g., the RAS/MEK/ERK pathway, whereas others are silenced (e.g. HNF-4α), resulting in up- and downregulation of hundreds of genes.One key message is that despite our enthusiasm for in vitro systems, we must never lose sight of the in vivo situation.Although hepatocytes have been isolated for decades, the hunt for relevant alternative systems has only just begun.

View Article: PubMed Central - PubMed

Affiliation: Leibniz Research Centre for Working Environment and Human Factors (IFADO), 44139, Dortmund, Germany.

ABSTRACT
This review encompasses the most important advances in liver functions and hepatotoxicity and analyzes which mechanisms can be studied in vitro. In a complex architecture of nested, zonated lobules, the liver consists of approximately 80 % hepatocytes and 20 % non-parenchymal cells, the latter being involved in a secondary phase that may dramatically aggravate the initial damage. Hepatotoxicity, as well as hepatic metabolism, is controlled by a set of nuclear receptors (including PXR, CAR, HNF-4α, FXR, LXR, SHP, VDR and PPAR) and signaling pathways. When isolating liver cells, some pathways are activated, e.g., the RAS/MEK/ERK pathway, whereas others are silenced (e.g. HNF-4α), resulting in up- and downregulation of hundreds of genes. An understanding of these changes is crucial for a correct interpretation of in vitro data. The possibilities and limitations of the most useful liver in vitro systems are summarized, including three-dimensional culture techniques, co-cultures with non-parenchymal cells, hepatospheres, precision cut liver slices and the isolated perfused liver. Also discussed is how closely hepatoma, stem cell and iPS cell-derived hepatocyte-like-cells resemble real hepatocytes. Finally, a summary is given of the state of the art of liver in vitro and mathematical modeling systems that are currently used in the pharmaceutical industry with an emphasis on drug metabolism, prediction of clearance, drug interaction, transporter studies and hepatotoxicity. One key message is that despite our enthusiasm for in vitro systems, we must never lose sight of the in vivo situation. Although hepatocytes have been isolated for decades, the hunt for relevant alternative systems has only just begun.

Show MeSH
Related in: MedlinePlus