Ca(2+)-dependent protein kinase C isoforms are critical to estradiol 17beta-D-glucuronide-induced cholestasis in the rat.
Ca(2+)-dependent protein kinase C isoforms are critical to estradiol 17beta-D-glucuronide-induced cholestasis in the rat.
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DOI：
10.1002/hep.22532
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发表时间：
2008-12
期刊：
影响因子：
13.5
通讯作者：
Vore, Mary
中科院分区：
文献类型：
--
作者：
Crocenzi, Fernando A.;Pozzi, Enrique J. Sanchez;Ruiz, Maria Laura;Zucchetti, Andres E.;Roma, Marcelo G.;Mottino, Aldo D.;Vore, Mary
内源性雌二醇代谢物雌二醇17β- d -葡萄糖醛酸酯（E217G）诱导大鼠肝脏急性胆汁淤滞，同时小管转运体Bsep （Abcc11）和Mrp2 （Abcc2）的恢复及其相关功能丧失。我们评估了Ca2+依赖性PKC异构体（cPKC）参与灌注大鼠肝脏（PRL）和分离大鼠肝细胞偶联（IRHC）中E217G的胆汁淤积表现。在PRL中，E217G （2 μmol/肝，门静脉内，单次注射）最大限度地减少了胆汁流量、总谷胱甘肽和[3H]牛磺胆酸盐的排泄量，分别减少了61%、62%和79%；在灌注液中掺入特异性cPKC抑制剂Gö6976 （500 nM）几乎完全阻止了这些下降。在IRHC的剂量效应研究中，E217G （3.75-800 μM）降低了Bsep底物胆酰赖基荧光素的微管液泡积累，IC50为54.9±7.9 μM。Gö6976 （1 μM）使IC50增加到178.4±23.1 μM，同样阻止了Mrp2底物谷胱甘肽甲基荧光素小管空泡积累的减少。正如在PRL和IRHC中检测到的那样，Gö6976对这些变化的预防与对e217g诱导的Bsep和Mrp2从管膜上的回收的完全保护相一致。E217G也增加了IRHC的细胞旁通透性，Gö6976仅部分阻止了这一作用。原代培养的大鼠肝细胞经E217G处理后，cPKC异构体PKCα易位到质膜上，而非与Ca2+无关的PKC异构体PKCε易位；Gö6976完全阻止了这种易位，从而表明cPKC的特异性激活。这与western blotting检测到的E217G增加cPKC的自磷酸化一致。我们的研究结果支持cPKC异构体在e217g诱导的胆汁淤滞中发挥核心作用，通过诱导从管膜转运体的恢复和细胞旁通路的打开。
The endogenous estradiol metabolite estradiol 17β-D-glucuronide (E217G) induces an acute cholestasis in rat liver coincident with retrieval of the canalicular transporters Bsep (Abcc11) and Mrp2 (Abcc2) and their associated loss of function. We assessed the participation of Ca2+-dependent PKC isoforms (cPKC) in the cholestatic manifestations of E217G in the perfused rat liver (PRL) and in isolated rat hepatocyte couplets (IRHC). In the PRL, E217G (2 μmol/liver; intraportal, single injection) maximally decreased bile flow, total glutathione and [3H] taurocholate excretion by 61, 62, and 79%, respectively; incorporation of the specific cPKC inhibitor Gö6976 (500 nM) in the perfusate almost totally prevented these decreases. In dose-response studies using IRHC, E217G (3.75–800 μM) decreased the canalicular vacuolar accumulation of the Bsep substrate cholyl-lysylfluorescein with an IC50 of 54.9 ± 7.9 μM. Gö6976 (1 μM) increased the IC50 to 178.4 ± 23.1 μM, and similarly prevented the decrease in the canalicular vacuolar accumulation of the Mrp2 substrate, glutathione methylfluorescein. Prevention of these changes by Gö6976 coincided with complete protection against E217G-induced retrieval of Bsep and Mrp2 from the canalicular membrane, as detected both in the PRL and IRHC. E217G also increased paracellular permeability in IRHC, which was only partially prevented by Gö6976. The cPKC isoform PKCα, but not the Ca2+-independent PKC isoform, PKCε, translocated to the plasma membrane after E217G administration in primary cultured rat hepatocytes; Gö6976 completely prevented this translocation, thus indicating specific activation of cPKC. This is consistent with increased autophosphorylation of cPKC by E217G, as detected by western blotting. Our findings support a central role for cPKC isoforms in E217G-induced cholestasis, by inducing both transporter retrieval from the canalicular membrane and opening of the paracellular route.
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DOI：
10.1124/jpet.103.054544
发表时间：
2003-10-01
影响因子：
3.5
作者：
Mottino, AD;Veggi, LM;Vore, M
通讯作者：
Vore, M
DOI：
10.1152/ajpgi.00496.2006
发表时间：
2007-07-01
影响因子：
4.5
作者：
Mottino, Aldo D.;Hoffman, Tim;Vore, Mary
通讯作者：
Vore, Mary
影响因子：
10.6
作者：
Haussinger, Dieter;Kubitz, Ralf;Schliess, Freimut
通讯作者：
Schliess, Freimut
影响因子：
13.5
作者：
Kubitz, R;Huth, C;Häussinger, D
通讯作者：
Häussinger, D
影响因子：
4.1
作者：
MITCHELL, FE;MARAIS, RM;PARKER, PJ
通讯作者：
PARKER, PJ