Protein kinase C–dependent distribution of the multidrug resistance protein 2 from the canalicular to the basolateral membrane in human HepG2 cells

Kubitz, Ralf; Huth, Clemens; Schmitt, Marcus; Horbach, Axel; Kullak‐Ublick, Gerd A.; Häussinger, Dieter

doi:10.1053/jhep.2001.25959

Cited by 108 publications

(73 citation statements)

References 59 publications

(74 reference statements)

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“…9D-F), which is in line with an involvement of PKC-isoforms in bile secretion. 21,26,46,47 The identification of the responsible isoform needs further investigation.…”

Section: Discussionmentioning

confidence: 99%

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Short-term feedback regulation of bile salt uptake by bile salts in rodent liver

et al. 2012

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The sodium taurocholate cotransporting polypeptide (Ntcp) is the major bile salt uptake transporter at the sinusoidal membrane of hepatocytes. Short-term feedback regulation of Ntcp by primary bile salts has not yet been investigated in vivo. Subcellular localization of Ntcp was analyzed in Ntcp-transfected HepG2-cells by flow cytometry and in immunofluorescence images from tissue sections by a new automated image analysis method. Net bile salt uptake was investigated in perfused rat liver by a pulse chase technique. In Flag-Ntcp-EGFP (enhanced green fluorescent protein) expressing HepG2-cells, taurochenodeoxycholate (TCDC), but not taurocholate (TC), induced endocytosis of Ntcp. TCDC, but not TC, caused significant internalization of Ntcp in perfused rat livers, as shown by an increase in intracellular Ntcp immunoreactivity, whereas Bsep distribution remained unchanged. These results correlate with functional studies. Rat livers were continuously perfused with 100 mu mol/L of TC. 25 mu mol/L of TCDC, taurodeoxycholate (TDC), tauroursodeoxycholate (TUDC), or TC were added for 30 minutes, washed out, followed by a pulse of (3)[H]-TC. TCDC, but not TDC, TUDC, or TC significantly increased the amount of (3)[H]-TC in the effluent, indicating a reduced sinusoidal net TC uptake. This effect was sensitive to chelerythrine (protein kinase C inhibitor) and cypermethrin (protein phosphatase 2B inhibitor). Phosphoinositide 3-kinase (PI3K) inhibitors had an additive effect, whereas Erk1/2 (extracellular signal activated kinase 1/2), p38MAPK, protein phosphatase 1/2A (PP1/2A), and reactive oxygen species (ROS) were not involved. Conclusion: TCDC regulates bile salt transport at the sinusoidal membrane by protein kinase C-and protein phosphatase 2B-mediated retrieval of Ntcp from the plasma membrane. During increased portal bile salt load this mechanism may adjust bile salt uptake along the acinus and protect periportal hepatocytes from harmful bile salt concentrations

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“…9D-F), which is in line with an involvement of PKC-isoforms in bile secretion. 21,26,46,47 The identification of the responsible isoform needs further investigation.…”

Section: Discussionmentioning

confidence: 99%

“…Phorbolesters activate the MAP kinase kinase MEK1 by way of PKC. 26 To test whether MEK1 is a downstream effector of TCDC, livers were perfused with the MEK1 inhibitor PD98059. An effect on TC* recovery in the effluent or secretion into bile was not observed.…”

Section: Tcdc Induces Redistribution Of Ntcp In Perfusedmentioning

confidence: 99%

Short-term feedback regulation of bile salt uptake by bile salts in rodent liver

et al. 2012

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“…A cell type-dependent localization, as detected for ABCC4, which is present in the basolateral membrane of human hepatocytes [140] and in the apical membrane of kidney proximal tubule epithelial cells [174], has not been observed for ABCC2. Under certain experimental conditions, ABCC2 may be redistributed to the basolateral membrane, e.g., in rat hepatocyte couplets shortly after their isolation [142] and in human HepG2 cells after protein kinase C activation [100].…”

Section: Localization Of Abcc2 In Polarized Cells and Tissuesmentioning

confidence: 99%

The apical conjugate efflux pump ABCC2 (MRP2)

Nies

Keppler

2006

Pflugers Arch - Eur J Physiol

352

255

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ABCC2 is a member of the multidrug resistance protein subfamily localized exclusively to the apical membrane domain of polarized cells, such as hepatocytes, renal proximal tubule epithelia, and intestinal epithelia. This localization supports the function of ABCC2 in the terminal excretion and detoxification of endogenous and xenobiotic organic anions, particularly in the unidirectional efflux of substances conjugated with glutathione, glucuronate, or sulfate, as exemplified by leukotriene C 4 , bilirubin glucuronosides, and some steroid sulfates. The hepatic ABCC2 pump contributes to the driving forces of bile flow. Acquired or hereditary deficiency of ABCC2, the latter known as Dubin-Johnson syndrome in humans, causes an increased concentration of bilirubin glucuronosides in blood because of their efflux from hepatocytes via the basolateral ABCC3, which compensates for the deficiency in ABCC2-mediated apical efflux. In this article we provide an overview on the molecular characteristics of ABCC2 and its expression in various tissues and species. We discuss the transcriptional and posttranscriptional regulation of ABCC2 and review approaches to the functional analysis providing information on its substrate specificity. A comprehensive list of sequence variants in the human ABCC2 gene summarizes predicted and proven functional consequences, including variants leading to Dubin-Johnson syndrome. Keywords

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“…The function of several human transport proteins is regulated by PKC activation. For example, PKC activation downregulates transport function of organic anion transporter (OAT) 1 (Zhang et al, 2008), OAT3 (Duan et al, 2010), and OAT4 (Zhou et al, 2007;Zhang et al, 2010); OATP2B1 (Köck et al, 2010) and OATP1A2 (Zhou et al, 2011); efflux transport protein P-glycoprotein (P-gp) (Miller et al, 1998); and multidrug resistance protein (MRP)2 (Kubitz et al, 2001). OATP1B3 has putative PKC phosphorylation sites as predicted by Scansite 3 (Obenauer et al, 2003).…”

Section: Introductionmentioning

confidence: 99%

Novel Mechanism of Impaired Function of Organic Anion-Transporting Polypeptide 1B3 in Human Hepatocytes: Post-Translational Regulation of OATP1B3 by Protein Kinase C Activation

et al. 2014

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The organic anion-transporting polypeptide (OATP) 1B3 is a membrane transport protein that mediates hepatic uptake of many drugs and endogenous compounds. Currently, determination of OATP-mediated drug-drug interactions in vitro is focused primarily on direct substrate inhibition. Indirect inhibition of OATP1B3 activity is under-appreciated. OATP1B3 has putative protein kinase C (PKC) phosphorylation sites. Studies were designed to determine the effect of PKC activation on OATP1B3-mediated transport in human hepatocytes using cholecystokinin-8 (CCK-8), a specific OATP1B3 substrate, as the probe. A PKC activator, phorbol-12-myristate-13-acetate (PMA), did not directly inhibit [ 3 H]CCK-8 accumulation in human sandwich-cultured hepatocytes (SCH). However, pretreatment with PMA for as little as 10 minutes rapidly decreased [ 3 H]CCK-8 accumulation. Treatment with a PKC inhibitor bisindolylmaleimide (BIM) I prior to PMA treatment blocked the inhibitory effect of PMA, indicating PKC activation is essential for downregulating OATP1B3 activity. PMA pretreatment did not affect OATP1B3 mRNA or total protein levels. To determine the mechanism(s) underlying the indirect inhibition of OATP1B3 activity upon PKC activation, adenoviral vectors expressing FLAG-Myc-tagged OATP1B3 (Ad-OATP1B3) were transduced into human hepatocytes; surface expression and phosphorylation of OATP1B3 were determined by biotinylation and by an anti-phosphor-Ser/Thr/Tyr antibody, respectively. PMA pretreatment markedly increased OATP1B3 phosphorylation without affecting surface or total OATP1B3 protein levels. In conclusion, PKC activation rapidly decreases OATP1B3 transport activity by posttranslational regulation of OATP1B3. These studies elucidate a novel indirect inhibitory mechanism affecting hepatic uptake mediated by OATP1B3, and provide new insights into predicting OATP-mediated drug interactions between OATP substrates and kinase modulator drugs/endogenous compounds.

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Protein kinase C–dependent distribution of the multidrug resistance protein 2 from the canalicular to the basolateral membrane in human HepG2 cells

Cited by 108 publications

References 59 publications

Short-term feedback regulation of bile salt uptake by bile salts in rodent liver

Short-term feedback regulation of bile salt uptake by bile salts in rodent liver

The apical conjugate efflux pump ABCC2 (MRP2)

Novel Mechanism of Impaired Function of Organic Anion-Transporting Polypeptide 1B3 in Human Hepatocytes: Post-Translational Regulation of OATP1B3 by Protein Kinase C Activation

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