Progressive familial intrahepatic cholestasis type 2 (PFIC2) is a severe autosomal recessive cholestatic liver disease due to variations in ATP-binding cassette subfamily B member 11 (ABCB11) gene. The clinical and molecular consequences of two missense variations affecting the same ABCB11 residue (T463) were characterized, and pharmacological strategies were investigated. Clinical and genetic data were collected from two PFIC2 patients carrying p.T463I or p.T463P substitutions. A three-dimensional (3-D) structure analysis was performed to predict substitution impacts. ABCB11T463I and ABCB11T463P variants were expressed in HepG2 and Madin-Darby canine kidney cells to assess their subcellular localization and functional activity. Pharmacological modulators were tested to correct the defects. The patient carrying ABCB11T463I exhibited a mild phenotype and responded to surgical biliary diversion. Conversely, the patient carrying ABCB11T463P required a liver transplantation before age one. 3-D structure and in vitro analyses predicted a functional defect in both variants and a folding defect for the T463P variant. In vitro, ursodeoxycholic acid combined with glycerol phenylbutyrate increased ABCB11T463P canalicular expression (40.2 ± 7.7% of the wild type, P < 0.0001) and improved transport activity (32.4 ± 10.3% of the wild type, P < 0.0001). VX-770 and SBC040 increased ABCB11T463I function from 37.9 ± 2.5% (DMSO) to 73.2 ± 12.3% and 76.1 ± 17.5%, respectively, of the wild-type activity (P < 0.0001). ABCB11 missense variations, even affecting the same residue, can cause various molecular defects, resulting in mild to severe phenotypes. 3-D structure and in vitro analyses could be used to predict the severity of missense variants and guide the treatment of PFIC2 patients with pharmacological modulators.NEW & NOTEWORTHY Patients with progressive familial intrahepatic cholestasis type 2 (PFIC2) due to ATP-binding cassette subfamily B member 11 (ABCB11) missense variations may present various phenotypes and exhibit different response patterns to treatments. This study exemplifies this variability and provides an in silico and in vitro framework for characterizing and classifying ABCB11 missense variants. This classification could serve to guide treatment strategies, stratify patients with missense variants in clinical trials, and predict patient outcomes.

Background & Aims P2X4R is a lysosomal ATP-gated cation channel receptor, playing roles in liver pathophysiology through poorly understood mechanisms. We aim at defining the role of P2X4R in macroautophagy and lipid droplet (LD) homeostasis. Methods We used P2X4R-KO, LC3-GFP transgenic and WT mice, a specific P2X4R antagonist (BAY1797), and three experimental models of steatosis (n = 5–10 mice per group). Autophagic flux was measured in human embryonic kidney reporter cell line, and Atg5-/- mouse embryonic fibroblasts. Oleic acid cell loading, Oil Red O and LipidTox cell and tissue staining, and LC3-II Western blotting were performed. Results The autophagic flux in the liver and in primary isolated hepatocytes was decreased in P2X4R-KO mice compared with WT mice, as well as in BAY1797 (compared with vehicle)-treated WT animals and hepatocytes. P2X4R overexpression stimulated the autophagic flux, indicating an impact of P2X4R on lysosome-autophagosome fusion. BAY1797 treatment in fasted mice as well as in both methionine- and choline-deficient diet and high-fat, high-sucrose, cholesterol-containing diet models resulted in small LD instead of large LD steatosis (vehicle-treated mice) and stimulated cytosolic lipolysis. Similarly, BAY1797 inhibited lipophagy and stimulated cytosolic lipolysis in vitro in oleic acid-loaded primary hepatocytes and in mouse embryonic fibroblasts, resulting in smaller LDs. Lysosome position analysis upon starvation revealed that P2X4R inhibition interfered with lysosomal trafficking in vitro. In patients with metabolic dysfunction-associated steatotic liver disease (n = 24), we found a correlation between LD size, autophagic flux, and P2X4R expression. Conclusions P2X4R inhibition decreased the autophagic flux in hepatocytes, resulting in LD size reduction, during fasting- as well as diet-induced steatosis in mice. P2X4R is proposed as a new therapeutic target to modulate lipophagy in the liver. Impact and implications We provide in vitro and in vivo evidence that P2X4R is a regulator of macroautophagy, and thereby affects LD homeostasis in the liver. Both genetic deletion and specific pharmacological inhibition of P2X4R results in LD size reduction in three murine models of fatty liver, in association with inhibition of lipophagy, stimulation of lipolysis, and reduction of liver inflammation. Finally, in a series of human patients with MASLD, we found that P2X4R expression correlated with autophagic flux and LD size. Thus, based on our data, we report that P2X4R inhibition is hepatoprotective in the context of MASLD.

To control capillary bleeding, surgeons may use absorbable hemostatic agents, such as Surgicel® and TachoSil®. Due to their slow resorption, their persistence in situ can have a negative impact on tissue repair in the resected organ. To avoid complications and obtain a hemostatic agent that promotes tissue repair, a zinc-supplemented calcium alginate compress was developed: HEMO-IONIC®. This compress is non-absorbable and is therefore removed once hemostasis has been achieved. After demonstrating the hemostatic efficacy and stability of the blood clot obtained with HEMO-IONIC, the impact of Surgicel, TachoSil, and HEMO-IONIC on cell activation and tissue repair were compared (i) in vitro on endothelial cells, which are essential to tissue repair, and (ii) in vivo in a mouse skin excision model. In vitro, only HEMO-IONIC maintained the phenotypic and functional properties of endothelial cells and induced their migration. In comparison, Surgicel was found to be highly cytotoxic, and TachoSil inhibited endothelial cell migration. In vivo, only HEMO-IONIC increased angiogenesis, the recruitment of cells essential to tissue repair (macrophages, fibroblasts, and epithelial cells), and accelerated maturation of the extracellular matrix. These results demonstrate that a zinc-supplemented calcium alginate, HEMO-IONIC, applied for 10 min at the end of surgery and then removed has a long-term positive effect on all phases of tissue repair.

During liver injury and cholestasis, the mechanisms allowing the organ to protect itself with the aim of maintaining biliary homeostasis are not completely understood. Central to their biological roles, bile acids (BAs) and their receptors constitute a signaling network with multiple molecular and cellular impacts on both liver repair and protection from BA overload. BA signal through nuclear [mainly farnesoid X receptor (FXR)] and membrane [mainly G protein-coupled BA receptor 1 (GPBAR-1), aka Takeda G protein-coupled receptor 5 (TGR5)] receptors, in which activation elicits a wide array of biological responses. So far, most of the studies have been focused on FXR signaling as hepato-protective, TGR5 being less explored to this regard. While the liver faces massive and potentially harmful BA overload during cholestasis, it is crucial to understand that BAs induce also protective responses contributing not only to reduce the inflammatory burden, but also to spare liver cells and their repair capacities. Based on the available literature, the TGR5 BA receptor protects the liver in the cholestatic context and counteracts BA overload with the aim of restoring biliary homeostasis mainly through the control of inflammatory processes, biliary epithelial barrier permeability, and BA pool composition. Mouse experimental models of cholestasis reveal that the lack of TGR5 was associated with exacerbated inflammation and necrosis, leaky biliary epithelium, and excessive BA pool hydrophobicity, resulting in biliary cell and parenchymal insult, and compromising optimal restoration of biliary homeostasis and liver repair. There are thus widely opened translational perspectives with the aim of targeting TGR5-related signaling or biological responses to trigger protection of the cholestatic liver.

A bstract Background & aim ABCB4 is expressed at the canalicular membrane of hepatocytes. This ATP‐binding cassette (ABC) transporter is responsible for the secretion of phosphatidylcholine into bile canaliculi. Missense genetic variations of ABCB4 are correlated with several rare cholestatic liver diseases, the most severe being progressive familial intrahepatic cholestasis type 3 (PFIC3). In a repurposing strategy to correct intracellularly retained ABCB4 variants, we tested 16 compounds previously validated as cystic fibrosis transmembrane conductance regulator (CFTR) correctors. Methods The maturation, intracellular localization and activity of intracellularly retained ABCB4 variants were analyzed in cell models after treatment with CFTR correctors. In addition, in silico molecular docking calculations were performed to test the potential interaction of CFTR correctors with ABCB4. Results We observed that the correctors C10, C13, and C17, as well as the combinations of C3 + C18 and C4 + C18, allowed the rescue of maturation and canalicular localization of four distinct traffic‐defective ABCB4 variants. However, such treatments did not permit a rescue of the phosphatidylcholine secretion activity of these defective variants and were also inhibitory of the activity of wild type ABCB4. In silico molecular docking analyses suggest that these CFTR correctors might directly interact with transmembrane domains and/or ATP‐binding sites of the transporter. Conclusion Our results illustrate the uncoupling between the traffic and the activity of ABCB4 because the same molecules can rescue the traffic of defective variants while they inhibit the secretion activity of the transporter. We expect that this study will help to design new pharmacological tools with potential clinical interest.

During liver repair after injury, bile secretion has to be tightly modulated in order to preserve liver parenchyma from bile acid (BA)-induced injury. The mechanisms allowing the liver to maintain biliary homeostasis during repair after injury are not completely understood. Besides their historical role in lipid digestion, bile acids (BA) and their receptors constitute a signalling network with multiple impacts on liver repair, both stimulating regeneration and protecting the liver from BA overload. BA signal through nuclear (mainly Farnesoid X Receptor, FXR) and membrane (mainly G Protein-coupled BA Receptor 1, GPBAR-1 or TGR5) receptors to elicit a wide array of biological responses. While a great number of studies have been dedicated to the hepato-protective impact of FXR signalling, TGR5 is by far less explored in this context. Because the liver has to face massive and potentially harmful BA overload after partial ablation or destruction, BA-induced protective responses crucially contribute to spare liver repair capacities. Based on the available literature, the TGR5 BA receptor protects the remnant liver and maintains biliary homeostasis, mainly through the control of inflammation, biliary epithelial barrier permeability, BA pool hydrophobicity and sinusoidal blood flow. Mouse experimental models of liver injury reveal that in the lack of TGR5, excessive inflammation, leaky biliary epithelium and hydrophobic BA overload result in parenchymal insult and compromise optimal restoration of a functional liver mass. Translational perspectives are thus opened to target TGR5 with the aim of protecting the liver in the context of injury and BA overload.

Backgrounds & Aims As the bile acid (BA) pool composition is of major impact on liver pathophysiology, we studied its regulation by the BA receptor TGR5, promoting hepatoprotection against BA overload. Methods WT, total and hepato-specific TGR5-KO, and TGR5-overexpressing mice were used in: partial and 90% extended hepatectomies (EH) upon normal, ursodeoxycholic acid (UDCA)- or cholestyramine (CT)-enriched diet, bile duct ligation (BDL), cholic acid (1%)-enriched diet, and TGR5 agonist (RO) treatments. We thereby studied TGR5 impact on: BA pool composition, liver injury, regeneration and survival. Particular focus was made on gut microbiota (GM) and gallbladder (GB) function analysis. BA pool composition was analyzed in patients undergoing major hepatectomy. Results The TGR5-KO hyperhydrophobic BA pool was not related to BA synthesis alteration, nor to the TGR5-KO GM dysbiosis, as supported by hepatocyte-specific KO mice and cohousing experiments. The TGR5-dependent control of GB dilatation was crucial for BA pool composition, as determined by experiments including RO treatment +/− cholecystectomy. The poor TGR5-KO post-EH survival rate, related with exacerbated peribiliary necrosis and BA overload, was improved by shifting the BA pool towards a more hydrophilic composition (CT and UDCA treatments). After either BDL or CA-enriched diet +/− cholecystectomy, we found that GB dilatation had strong TGR5-dependent hepatoprotective properties. In patients, a more hydrophobic BA pool was correlated with an unfavorable outcome after hepatectomy. Conclusion BA pool composition is crucial for hepatoprotection in mice and humans. We point TGR5 as a key regulator of BA profile and thereby as a potential hepatoprotective target under BA overload conditions. Lay summary Through multiple in vivo experimental approaches in mice, together with a patients study, this work brings some new light on the relationships between biliary homeostasis, gallbladder function and liver protection. We showed that the bile acid pool composition is crucial for optimal liver repair, not only in mice but also in human patients undergoing major hepatectomy.

BACKGROUND & AIMS:Liver fibrosis is characterized by the accumulation of extracellular matrix produced by hepatic myofibroblasts (hMF), the activation of which is critical to the fibrogenic process. Extracellular ATP, released by dying or stressed cells, and its purinergic receptors, constitute a powerful signaling network after injury. Although the purinergic receptor P2X4 (P2RX4) is highly expressed in the liver, its functions in hMF had never been investigated during liver fibrogenesis.METHODS:In vivo, bile duct ligation was performed and methionine- and choline-deficient diet administered in wild-type and P2x4 knock-out (P2x4-KO) mice. In vitro, hMF were isolated from mouse (wild-type and P2x4-KO) and human liver. P2X4 pharmacological inhibition (in vitro and in vivo) and P2X4 siRNAs (in vitro) were used. Histological, biochemical and cell culture analysis allowed us to study P2X4 expression and its involvement in the regulation of fibrogenic and fibrolytic factors, as well as of hMF activation markers and properties.RESULTS:P2X4 genetic invalidation or pharmacological inhibition protected mice from liver fibrosis and hMF accumulation after bile duct ligation or methionine- and choline-deficient diet. Human and mouse hMFs expressed P2X4, mainly in lysosomes. Invalidation of P2X4 in human and mouse hMFs blunted their activation marker expression and their fibrogenic properties. Finally, we showed that P2X4 regulates calcium entry and lysosomal exocytosis in hMF, impacting on ATP release, profibrogenic secretory profile, and transcription factor activation.CONCLUSION:P2X4 expression and activation is critical for hMF to sustain their activated and fibrogenic phenotype. Therefore, the inactivation of P2X4 may be of therapeutic interest during liver fibrotic diseases.LAY SUMMARY:During chronic injury, the liver often repairs with fibrotic tissue, which impairs liver function, and for which there is currently no treatment. We found that a previously unexplored pathway involving the purinergic receptor P2X4, can modulate fibrotic liver repair. Therefore, this receptor could be of interest in the development of novel therapies for fibrotic liver diseases.

Many regulatory pathways are involved in liver regeneration after partial hepatectomy (PH), to initiate growth, protect liver cells, and sustain remnant liver functions. Extracellular adenosine triphosphate rises in blood and bile after PH and contributes to liver regeneration, although purinergic receptors and mechanisms remain to be precisely explored. In this work we analyzed during regeneration after PH the involvement of P2X4 purinergic receptors, highly expressed in the liver. P2X4 receptor expression in the liver, liver histology, hepatocyte proliferation, plasma bile acid concentration, bile flow and composition, and lysosome distribution in hepatocytes were studied in wild‐type and P2X4 knockout (KO) mice, before and after PH. P2X4 receptors were expressed in hepatocytes and Kupffer cells; in hepatocytes, P2X4 was concentrated in subcanalicular areas closely costained with lysosomal markers. After PH, delayed regeneration, hepatocyte necrosis, and cholestasis were observed in P2X4‐KO mice. In P2X4‐KO mice, post‐PH biliary adaptation was impaired with a smaller increase in bile flow and HCO3− biliary output, as well as altered biliary composition with reduced adenosine triphosphate and lysosomal enzyme release. In line with these data, lysosome distribution and biogenesis were altered in P2X4‐KO compared with wild‐type mice. Conclusion: During liver regeneration after PH, P2X4 contributes to the complex control of biliary homeostasis through mechanisms involving pericanalicular lysosomes, with a resulting impact on hepatocyte protection and proliferation. (Hepatology 2016;64:941‐953)

Many regulatory pathways are involved in liver regeneration after partial hepatectomy (PH) to initiate growth, protect liver cells, and sustain functions of the remnant liver. Bile acids (BAs), whose levels rise in the blood early after PH, stimulate both hepatocyte proliferation and protection, in part through their binding to the nuclear farnesoid X receptor (FXR). However, the effect of the BA receptor, TGR5 (G‐protein‐coupled BA receptor 1) after PH remains to be studied. Liver histology, hepatocyte proliferation, BA concentrations (plasma, bile, liver, urine, and feces), bile flow and composition, and cytokine production were studied in wild‐type (WT) and TGR5 KO (knockout) mice before and after PH. BA composition (plasma, bile, liver, urine, and feces) was more hydrophobic in TGR5 KO than in WT mice. After PH, severe hepatocyte necrosis, prolonged cholestasis, exacerbated inflammatory response, and delayed regeneration were observed in TGR5 KO mice. Although hepatocyte adaptive response to post‐PH BA overload was similar in WT and TGR5 KO mice, kidney and biliary adaptive responses were strongly impaired in TGR5 KO mice. Cholestyramine treatment, as well as Kupffer cell depletion, significantly improved the post‐PH TGR5 KO mice phenotype. After bile duct ligation or upon a cholic acid–enriched diet, TGR5 KO mice exhibited more severe liver injury than WT as well as impaired BA elimination in urine. Conclusion: TGR5 is crucial for liver protection against BA overload after PH, primarily through the control of bile hydrophobicity and cytokine secretion. In the absence of TGR5, intrahepatic stasis of abnormally hydrophobic bile and excessive inflammation, in association with impaired bile flow adaptation and deficient urinary BA efflux, lead to BA overload‐induced liver injury and delayed regeneration. (Hepatology 2013;58:1451–1460)

After partial hepatectomy (PH) the initial mass of the organ is restored through a complex network of cellular interactions that orchestrate both proliferative and hepatoprotective signalling cascades. Among agonists involved in this network many of them drive Ca2+ movements. During liver regeneration in the rat, hepatocyte cytosolic Ca2+ signalling has been shown on the one hand to be deeply remodelled and on the other hand to enhance progression of hepatocytes through the cell cycle. Mechanisms through which cytosolic Ca2+ signals impact on hepatocyte cell cycle early after PH are not completely understood, but at least they include regulation of immediate early gene transcription and ERK and CREB phosphorylation. In addition to cytosolic Ca2+, there is also evidence that mitochondrial Ca2+ and also nuclear Ca2+ may be critical for the regulation of liver regeneration. Finally, Ca2+ movements in hepatocytes, and possibly in other liver cells, not only impact hepatocyte progression in the cell cycle but more generally may regulate cellular homeostasis after PH.

Background & Aims: Early neuroendocrine pathways contribute to liver regeneration after partial hepatectomy (PH). We investigated one of these pathways involving acute cholestasis, immediate portal hyperpressure, and arginine vasopressin (AVP) secretion.Methods: Surgical procedure (PH, Portal vein stenosis (PVS), bile duct ligation (BDL), spinal cord lesion (SCL)) and treatments (capsaicin, bile acids (BA), oleanolic acid (OA)) were performed on rats and/or wild type or TGR5 (GPBAR1) knock-out mice. In these models, the activation of AVP-secreting supraoptic nuclei (SON) was analyzed, as well as plasma BA, AVP, and portal vein pressure (PVP). Plasma BA, AVP, and PVP were also determined in human living donors for liver transplantation.Results: Acute cholestasis (mimicked by BDL or BA injection) as well as portal hyperpressure (mimicked by PVS) independently activated SON and AVP secretion. BA accumulated in the brain after PH or BDL, and TGR5 was expressed in SON. SON activation was mimicked by the TGR5 agonist OA and inhibited in TGR5 KO mice after BDL. An afferent nerve pathway also contributed to post-PH AVP secretion, as capsaicin treatment or SCL resulted in a weaker SON activation after PH.Conclusions: After PH in rodents, acute cholestasis and portal hypertension, via the nervous and endocrine routes, stimulate the secretion of AVP that may protect the liver against shear stress and bile acids overload. Data in living donors suggest that this pathway may also operate in humans. (C) 2010 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

Liver regeneration is regulated by growth factors, cytokines, and other endocrine and metabolic factors. Calcium is important for cell division, but its role in liver regeneration is not known. The purpose of this study was to understand the effects of cytosolic calcium signals in liver growth after partial hepatectomy (PH). The gene encoding the calcium-binding protein parvalbumin (PV) targeted to the cytosol using a nuclear export sequence (NES), and using a discosoma red fluorescent protein (DsR) marker, was transfected into rat livers by injecting it, in recombinant adenovirus (Ad), into the portal vein. We performed two-thirds PH 4 days after Ad-PV-NES-DsR or Ad-DsR injection, and liver regeneration was analyzed. Calcium signals were analyzed with fura-2-acetoxymethyl ester in hepatocytes isolated from Ad-infected rats and in Ad-infected He la cells. Also, isolated hepatocytes were infected with Ad-DsR or Ad-PV-NES-DsR and assayed for bromodeoxyuridine incorporation. Ad-PV-NES-DsR injection resulted in PV expression in the hepatocyte cytosol. Agonist-induced cytosolic calcium oscillations were attenuated in both PV-NES-expressing Hela cells and hepatocytes, as compared to DsR-expressing cells. Bromodeoxyuridine incorporation (S phase), phosphorylated histone 3 immunostaining (mitosis), and liver mass restoration after PH were all significantly delayed in PV-NES rats. Reduced cyclin expression and retinoblastoma protein phosphorylation confirmed this observation. PV-NES rats exhibited reduced c-fos induction and delayed extracellular signal-regulated kinase 1/2 phosphorylation after PH. Finally, primary PV-NES expressing hepatocytes exhibited less proliferation and agonist-induced cyclic adenosine monophosphate responsive element binding and extracellular signal-regulated kinase 1/2 phosphorylation, as compared with control cells. Conclusion: Cytosolic calcium signals promote liver regeneration by enhancing progression of hepatocytes through the cell cycle. (HEPATOLOGY 201052:602-611)

Objective— Relationships between intracellular Ca 2+ concentration ([Ca 2+ ] cyt ) and apoptotic events, such as mitochondrial depolarization (ΔΨm loss) and Bcl-2 and Bad phosphorylation, were analyzed in platelets and Jurkat cells in relation to rapid procoagulant phosphatidylserine (PS) exposure. Methods and Results— Platelets were stimulated with A23187, thapsigargin (TG) and thrombin plus convulxin (Thr/Cvx), and Jurkat cells with ionomycin, in the presence or absence of cyclosporin A (CsA), a mitochondrial permeability transition pore inhibitor. ΔΨm loss occurred when platelets were stimulated in Ca 2+ medium in conditions exposing PS, but also in EGTA medium. CsA inhibited PS exposure, [Ca 2+ ] cyt increase, and ΔΨm loss in platelets stimulated with TG and Thr/Cvx, but had no inhibitory effect on A23187 stimulation. CsA reduced TG-induced Ca 2+ release from the endoplasmic reticulum and, consequently, external Ca 2+ influx. In ionomycin-stimulated Jurkat cells, rapid PS exposure was evidenced but not ΔΨm loss, and CsA did not inhibit the process. The status of phosphorylated Bad and Bcl-2 in both cell types remained unchanged on stimulation. Conclusions— Whether ΔΨm loss occurs or not, PS exposure is triggered by a high [Ca 2+ ] cyt increase. Data further demonstrate that CsA prevents membrane scrambling by inhibiting the high [Ca 2+ ] cyt increase, independently of its effect on mitochondrial permeability transition pore.

Background & Aims: Paracrine interactions are critical to liver physiology, particularly during regeneration, although physiological involvement of extracellular ATP, a crucial intercellular messenger, remains unclear. The physiological release of ATP into extracellular milieu and its impact on regeneration after partial hepatectomy were investigated in this study.Methods: Hepatic ATP release after hepatectomy was examined in the rat and in human living donors for liver transplantation. Quinacrine was used for in vivo staining of ATP-enriched compartments in rat liver sections and isolated hepatocytes. Rats were treated with an antagonist for purinergic receptors (Phosphate-6-azo(benzene-2,4-disulfonic acid), PPADS), and liver regeneration after hepatectomy was analyzed.Results: A robust and transient ATP release due to acute portal hyperpressure was observed immediately after hepatectomy in rats and humans. Clodronate liposomal pre-treatment partly inhibited ATP release in rats. Quinacrine-stained vesicles, co-labeled with a lysosomal marker in liver sections and isolated hepatocytes, were predominantly detected in periportal areas. These vesicles significantly disappeared after hepatectomy, in parallel with a decrease in liver ATP content. PPADS treatment inhibited hepatocyte cell cycle progression after hepatectomy, as revealed by a reduction in bromodeoxyuridine incorporation, phosphorylated histone 3 immunostaining, cyclin D1 and A expression and immediate early gene induction.Conclusion: Extracellular ATP is released immediately after hepatectomy from hepatocytes and Kupffer cells under mechanical stress and promotes liver regeneration in the rat. We suggest that in hepatocytes, ATP is released from a lysosomal compartment. Finally, observations made in living donors suggest that purinergic signalling could be critical for human liver regeneration. (C) 2009 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

Conclusions: Our data show that the stimulation of non-parenchymal liver cells by TLR agonists leads to induction or activation of cytokines or transcription factors that are known to have proand anti-regenerative properties. Therefore, the administration of TLR agonists with favorable ratios of proand anti-regenerative mediators before liver resection may be used for optimizing liver regeneration postoperatively.