The role of bile salts in liver regeneration

Aminodihydrophthalazinedione Sodium Transdermal Therapeutic System Specific Activity on an ExperimentalModel of Extensive Liver Resection

Previously, the authors showed that the application of the aminodihydrophthalazinedione sodium (ADPS) immunomodulator transdermal therapeutic system (TTS) to laboratory animals provides bioavailability analogous to the intramuscular administration of this drug at the same dose. At the same time, its maximum blood concentration is significantly reduced, and the retention time of the drug in the body is increased more than 10-fold, which can contribute to prolonging the drug effect. The aim of the work was to identify a possible positive effect of the transdermal administration of the ADPS immunomodulator on reparative liver regeneration on an experimental model of extensive liver resection (ELR). It has been shown that at a period of 48 h after ELR, the percutaneous administration of the immunomodulator has a pronounced stimulating effect on the mitotic activity of rat liver cells; by 72 h after ELR, an accelerated rate of recovery of hepatic homeostasis in the body was observed in laboratory animals in groups with the application of the ADPS TTS versus the control group.

Influence of cholestasis on portal vein embolization-induced hypertrophy of the future liver remnant

PURPOSE

In the pre-clinical setting, hepatocellular bile salt accumulation impairs liver regeneration following partial hepatectomy. Here, we study the impact of cholestasis on portal vein embolization (PVE)-induced hypertrophy of the future liver remnant (FLR).

METHODS

Patients were enrolled with perihilar cholangiocarcinoma (pCCA) or colorectal liver metastases (CRLM) undergoing PVE before a (extended) right hemihepatectomy. Volume of segments II/III was considered FLR and assessed on pre-embolization and post-embolization CT scans. The degree of hypertrophy (DH, percentual increase) and kinetic growth rate (KGR, percentage/week) were used to assess PVE-induced hypertrophy.

RESULTS

A total of 50 patients (31 CRLM, 19 pCCA) were included. After PVE, the DH and KGR were similar in patients with CRLM and pCCA (5.2 [3.3-6.9] versus 5.7 [3.2-7.4] %, respectively, p = 0.960 for DH; 1.4 [0.9-2.5] versus 1.9 [1.0-2.4] %/week, respectively, p = 0.742 for KGR). Moreover, pCCA patients with or without hyperbilirubinemia had comparable DH (5.6 [3.0-7.5] versus 5.7 [2.4-7.0] %, respectively, p = 0.806) and KGR (1.7 [1.0-2.4] versus 1.9 [0.8-2.4] %/week, respectively, p = 1.000). For patients with pCCA, unilateral drainage in FLR induced a higher DH than bilateral drainage (6.7 [4.9-7.9] versus 2.7 [1.5-4.2] %, p = 0.012). C-reactive protein before PVE was negatively correlated with DH (ρ = - 0.539, p = 0.038) and KGR (ρ = - 0.532, p = 0.041) in patients with pCCA.

CONCLUSIONS

There was no influence of cholestasis on FLR hypertrophy in patients undergoing PVE. Bilateral drainage and inflammation appeared to be negatively associated with FLR hypertrophy. Further prospective studies with larger and more homogenous patient cohorts are desirable.

Re-thinking of T-tube use in whole liver transplantation: an analysis on the risk of delayed graft function

The liver–gut axis has been identified as crucial mediator of liver regeneration. Thus, the use of a T-tube in liver transplantation (LT), which interrupts the enterohepatic bile circulation, may potentially have a detrimental effect on the early allograft functional recovery. We retrospectively analyzed a cohort of 261 patients transplanted with a whole liver graft, with a duct-to-duct biliary anastomosis, who did not develop any surgical complication within postoperative day 14. Early allograft dysfunction (EAD) was defined according to the criteria of Olthoff et al. (EAD-O), and graded according to the Model for Early Allograft Function (MEAF) score. EAD-O developed in 24.7% of recipients and the median MEAF score was 4.0 [interquartile range 2.9–5.5]. Both MEAF and EAD predicted 90-day post-LT mortality. A T-tube was used in 49.4% of cases (n = 129). After a propensity score matching for donor age, cold and warm ischemia time, donor risk index, balance of risk score, Child–Pugh class C, and MELD score, the T-tube group showed a significantly higher prevalence of EAD-O and value of MEAF than the no-T-tube group (EAD-O: 29 [34.1%] vs 16 [19.0%], p = 0.027; MEAF 4.5 [3.5–5.7] vs 3.7 [2.9–5.0], p = 0.014). In conclusion, T-tube use in LT may be a risk factor for EAD and higher MEAF, irrespective of graft quality and severity of pre-LT liver disease.

Prediction of Liver Weight Recovery by an Integrated Metabolomics and Machine Learning Approach After 2/3 Partial Hepatectomy

Liver has an ability to regenerate itself in mammals, whereas the mechanism has not been fully explained. Here we used a GC/MS-based metabolomic method to profile the dynamic endogenous metabolic change in the serum of C57BL/6J mice at different times after 2/3 partial hepatectomy (PHx), and nine machine learning methods including Least Absolute Shrinkage and Selection Operator Regression (LASSO), Partial Least Squares Regression (PLS), Principal Components Regression (PCR), k-Nearest Neighbors (KNN), Support Vector Machines (SVM), Random Forest (RF), eXtreme Gradient Boosting (xgbDART), Neural Network (NNET) and Bayesian Regularized Neural Network (BRNN) were used for regression between the liver index and metabolomic data at different stages of liver regeneration. We found a tree-based random forest method that had the minimum average Mean Absolute Error (MAE), Root Mean Squared Error (RMSE) and the maximum R square (R²) and is time-saving. Furthermore, variable of importance in the project (VIP) analysis of RF method was performed and metabolites with VIP ranked top 20 were selected as the most critical metabolites contributing to the model. Ornithine, phenylalanine, 2-hydroxybutyric acid, lysine, etc. were chosen as the most important metabolites which had strong correlations with the liver index. Further pathway analysis found Arginine biosynthesis, Pantothenate and CoA biosynthesis, Galactose metabolism, Valine, leucine and isoleucine degradation were the most influenced pathways. In summary, several amino acid metabolic pathways and glucose metabolism pathway were dynamically changed during liver regeneration. The RF method showed advantages for predicting the liver index after PHx over other machine learning methods used and a metabolic clock containing four metabolites is established to predict the liver index during liver regeneration.

Hepatoprotective Plants from Bangladesh: A Biophytochemical Review and Future Prospect

Liver diseases are quite prevalant in many densely populated countries, including Bangladesh. The liver and its hepatocytes are targeted by virus and microbes, as well as by chemical environmental toxicants, causing wide-spread disruption of metabolic fuctions of the human body, leading to death from end-stage liver diseases. The aim of this review is to systematically explore and record the potential of Bangladeshi ethnopharmacological plants to treat liver diseases with focus on their sources, constituents, and therapeutic uses, including mechanisms of actions (MoA). A literature survey was carried out using Pubmed, Google Scholar, ScienceDirect, and Scopus databases with articles reported until July, 2020. A total of 88 Bangladeshi hepatoprotective plants (BHPs) belonging to 47 families were listed in this review, including Euphorbiaceae, Cucurbitaceae, and Compositae families contained 20% of plants, while herbs were the most cited (51%) and leaves were the most consumed parts (23%) as surveyed. The effect of BHPs against different hepatotoxins was observed via upregulation of antioxidant systems and inhibition of lipid peroxidation which subsequently reduced the elevated liver biomarkers. Different active constituents, including phenolics, curcuminoids, cucurbitanes, terpenoids, fatty acids, carotenoids, and polysaccharides, have been reported from these plants. The hepatoameliorative effect of these constituents was mainly involved in the reduction of hepatic oxidative stress and inflammation through activation of Nrf2/HO-1 and inhibition of NF-κB signaling pathways. In summary, BHPs represent a valuable resource for hepatoprotective lead therapeutics which may offer new alternatives to treat liver diseases.

Bile Salt and FGF19 Signaling in the Early Phase of Human Liver Regeneration

The involvement of bile salt-fibroblast growth factor 19 (FGF19) signaling in human liver regeneration (LR) is not well studied. Therefore, we studied aspects of bile salt-FGF19 signaling shortly after liver resection in patients. We compared plasma bile salt and FGF19 levels in arterial, portal and hepatic venous blood, calculated venous-arterial differences (ΔVA), and determined hepatic transcript levels on two intra-operative time points: before (< 1 hour) and immediately after (> 2-3 hours) liver resection (i.e., following surgery). Postoperative bile salt and FGF19 levels were assessed on days 1, 2, and 3. LR was studied by computed tomography (CT)-liver volumetry. Following surgery, the liver, arterial, and portal bile salt levels were elevated (P < 0.05). Furthermore, an increased amount of bile salts was released in portal blood and extracted by the remnant liver (P < 0.05). Postoperatively, bile salt levels were elevated from day 1 onward (P < 0.001). For FGF19, intra-operative or postoperative changes of ΔVA or plasma levels were not observed. The bile salt-homeostatic regulator farnesoid X receptor (FXR) was markedly up-regulated following surgery (P < 0.001). Cell-cycle re-entry priming factors (interleukin 6 [IL-6], signal transducer and activator of transcription 3 [STAT3], and cJUN) were up-regulated following surgery and were positively correlated with FXR expression (P < 0.05). Postoperative hyperbilirubinemia was preceded by postsurgery low FXR and high Na+/Taurocholate cotransporting polypeptide (NTCP) expression in the remnant liver coupled with higher liver bile salt content (P < 0.05). Finally, bile salt levels on postoperative day 1 were an independent predictor of LR (P < 0.05). Conclusion: Systemic, portal, and liver bile salt levels are rapidly elevated after liver resection. Postoperative bile salts were positively associated with liver volume gain. In the studied time frame, FGF19 levels remained unaltered, suggesting that FGF19 plays a minor role in human LR. These findings indicate a more relevant role of bile salts in human LR.

Protection of liver sinusoids by intravenous administration of human Muse cells in a rat extra-small partial liver transplantation model

Small-for-size syndrome (SFSS) has a poor prognosis due to excessive shear stress and sinusoidal microcirculatory disturbances in the acute phase after living-donor liver transplantation (LDLT). Multilineage-differentiating stress enduring (Muse) cells are reparative stem cells found in various tissues and currently under clinical trials. These cells selectively home to damaged sites via the sphingosine-1-phosphate (S1P)-S1P receptor 2 system and repair damaged tissue by pleiotropic effects, including tissue protection and damaged/apoptotic cell replacement by differentiating into tissue-constituent cells. The effects of intravenously administered human bone marrow-Muse cells and -mesenchymal stem cells (MSCs) (4 × 105 ) on liver sinusoidal endothelial cells (LSECs) were examined in a rat SFSS model without immunosuppression. Compared with MSCs, Muse cells intensively homed to the grafted liver, distributed to the sinusoids and vessels, and delivered improved blood chemistry and Ki-67(+) proliferative hepatocytes and -LSECs within 3 days. Tissue clearing and three-dimensional imaging by multiphoton laser confocal microscopy revealed maintenance of the sinusoid continuity, organization, and surface area, as well as decreased sinusoid interruption in the Muse group. Small-interfering RNA-induced knockdown of hepatocyte growth factor and vascular endothelial growth factor-A impaired the protective effect of Muse cells on LSECs. Intravenous injection of Muse cells might be a feasible approach for LDLT with less recipient burden.

Bile acids as novel enhancers of CNS targeting antitumor drugs: a comprehensive review

Despite a relatively low prevalence of primary brain tumors, they continuously attract scientific interest because of the complexity of their treatment due to their location behind the blood-brain barrier. The main challenge in treatment of brain tumors is not the efficacy of the drugs, per se, but the low efficiency of drug delivery to malignant cells. At the core of the problem is the complex structure of the blood-brain barrier. Nowadays, there is evidence supporting the claim that bile acids have the ability to cross the blood-brain barrier. That ability can be exploited by taking a part in novel drug carrier designs. Bile acids represent a drug carrier system as a part of a mixed micelle composition, bilosomes and conjugates with various drugs. This review discusses the current knowledge related to bile acid molecules as drug penetration modifying agents, with the focus on central nervous system antitumor drug delivery.

An Italian survey on the use of T-tube in liver transplantation: old habits die hard!

There is enough clinical evidence that a T-tube use in biliary reconstruction at adult liver transplantation (LT) does not significantly modify the risk of biliary stricture/leak, and it may even sustain infective and metabolic complications. Thus, the policy on T-tube use has been globally changing, with progressive application of more restrictive selection criteria. However, there are no currently standardized indications in such change, and many LT Centers rely only on own experience and routine. A nation-wide survey was conducted among all the 20 Italian adult LT Centers to investigate the current policy on T-tube use. It was found that 20% of Centers completely discontinued the T-tube use, while 25% Centers used it routinely in all LT cases. The remaining 55% of Centers applied a selective policy, based on criteria of technical complexity of biliary reconstruction (72.7%), followed by low-quality graft (63.6%) and high-risk recipient (36.4%). A T-tube use > 50% of annual caseload was not associated with high-volume Center status (> 70 LT per year), an active pediatric or living-donor transplant program, or use of DCD grafts. Only 10/20 (50%) Centers identified T-tube as a potential risk factor for complications other than biliary stricture/leak. In these cases, the suspected pathogenic mechanism comprised bacterial colonization (70%), malabsorption (70%), interruption of the entero-hepatic bile-acid cycle (50%), biliary inflammation due to an indwelling catheter (40%) and gut microbiota changes (40%). In conclusion, the prevalence of T-tube use among the Italian LT Centers is still relatively high, compared to the European trend (33%), and the potential detrimental effect of T-tube, beyond biliary stricture/leak, seems to be somehow underestimated.

Molecular pathways of liver regeneration: A comprehensive review

The liver is a unique parenchymal organ with a regenerative capacity allowing it to restore up to 70% of its volume. Although knowledge of this phenomenon dates back to Greek mythology (the story of Prometheus), many aspects of liver regeneration are still not understood. A variety of different factors, including inflammatory cytokines, growth factors, and bile acids, promote liver regeneration and control the final size of the organ during typical regeneration, which is performed by mature hepatocytes, and during alternative regeneration, which is performed by recently identified resident stem cells called “hepatic progenitor cells”. Hepatic progenitor cells drive liver regeneration when hepatocytes are unable to restore the liver mass, such as in cases of chronic injury or excessive acute injury. In liver maintenance, the body mass ratio is essential for homeostasis because the liver has numerous functions; therefore, a greater understanding of this process will lead to better control of liver injuries, improved transplantation of small grafts and the discovery of new methods for the treatment of liver diseases. The current review sheds light on the key molecular pathways and cells involved in typical and progenitor-dependent liver mass regeneration after various acute or chronic injuries. Subsequent studies and a better understanding of liver regeneration will lead to the development of new therapeutic methods for liver diseases.

Liver regeneration observed across the different classes of vertebrates from an evolutionary perspective

The liver is a key organ that performs diverse functions such as metabolic processing of nutrients or disposal of dangerous substances (xenobiotics). Accordingly, it seems to be protected by several mechanisms throughout the life of organisms, one of which is compensatory hyperplasia, also known as liver regeneration. This review is a recapitulation of the scientific reports describing the different ways in which the various classes of vertebrates deal with liver injuries, where since mammals have an improved molecular toolkit, exhibit optimized regeneration of the liver compared to lower vertebrates. The main molecules involved in the compensatory process, such as proinflammatory and inhibitory cytokines, are analyzed across vertebrates with an evolutionary perspective. In addition, the possible significance of this mechanism is discussed in the context of the long life span of vertebrates, especially in the case of mammals.

[Liver regeneration: resolved and problem issues]

Liver is an exceptional organ due to unique anatomical and physiological features, as well as advanced regenerative ability. Discovery of molecular mechanisms governing liver regeneration allowed researchers to use them to enhance liver regeneration. However, significant progress in this area was achieved through the introduction of gene therapy. In this manuscript, the authors consider stem cells for cell therapy and tissue engineering, as well as an alternative to liver transplantation.

Liver Regeneration after Hepatectomy and Partial Liver Transplantation

The liver is a unique organ with an abundant regenerative capacity. Therefore, partial hepatectomy (PHx) or partial liver transplantation (PLTx) can be safely performed. Liver regeneration involves a complex network of numerous hepatotropic factors, cytokines, pathways, and transcriptional factors. Compared with liver regeneration after a viral- or drug-induced liver injury, that of post-PHx or -PLTx has several distinct features, such as hemodynamic changes in portal venous flow or pressure, tissue ischemia/hypoxia, and hemostasis/platelet activation. Although some of these changes also occur during liver regeneration after a viral- or drug-induced liver injury, they are more abrupt and drastic following PHx or PLTx, and can thus be the main trigger and driving force of liver regeneration. In this review, we first provide an overview of the molecular biology of liver regeneration post-PHx and -PLTx. Subsequently, we summarize some clinical conditions that negatively, or sometimes positively, interfere with liver regeneration after PHx or PLTx, such as marginal livers including aged or fatty liver and the influence of immunosuppression.

RNA-seq Used to Explore circRNA Expression and Identify Key circRNAs During the DNA Synthesis Phase of Mice Liver Regeneration

The liver has an excellent capacity for regeneration when faced with external injury and the damage differs from that of other organs in the body. Our aim was to identify the role of circular RNA (circRNA) during the DNA synthesis phase (36 h) of mice liver regeneration. High-throughput RNA sequencing was conducted to explore circRNA and messenger RNA (mRNA) expression in three pairs of mice liver tissue at 0 and 36 h after 2/3 partial hepatectomy. One hundred differentially expressed circRNAs were detected, including 66 upregulated and 34 downregulated circRNAs. We also explored 2483 differentially expressed mRNAs, including 1422 upregulated and 1061 downregulated mRNAs. Gene ontology and Kyoto Encyclopedia of Genes and Genomes indicated that cell cycle regulation, material metabolism, and multiple classical pathways were involved in the DNA synthesis process. A competing endogenous RNA (ceRNA) network containing 5 circRNAs, 28 target genes, and 533 microRNAs (miRNAs) was constructed, and we selected the top 5 miRNAs to map it. Potential key circRNAs were validated with the quantitative real-time PCR technique and their regeneration curves, including consecutive time points, were produced. Finally, a cell counting kit-8 assay on key circRNAs of ceRNA network was performed to further confirm their roles in the DNA synthesis phase of liver regeneration. This study provides a circRNA expression profile for liver regeneration and contributes valuable information for future research.

Bile Composition as a Diagnostic and Prognostic Tool in Liver Transplantation

Bile secretion and composition reflects the functional status of hepatocytes and cholangiocytes. Bile composition can have a role in the assessment of donor grafts before implantation in the recipient. In addition, changes in bile composition after liver transplantation can serve as a diagnostic and prognostic tool to predict posttransplant complications, such as primary nonfunction, acute cellular rejection, or nonanastomotic biliary strictures. With the popularization of liver machine perfusion preservation in the clinical setting, there is a revisited interest in biliary biomarkers to assess graft viability before implantation. This review discusses current literature on biliary biomarkers that could predict or assess liver graft and bile duct viability. Bile composition offers an exciting and novel perspective in the search for reliable hepatocyte and cholangiocyte viability biomarkers.

Coordinated cytochrome P450 expression in mouse liver and intestine under different dietary conditions during liver regeneration after partial hepatectomy

Liver resection is performed to remove tumors in patients with liver cancer, but the procedure's suitability depends on the regenerative ability of the liver. It is important to consider the effects of exogenous factors, such as diets, on liver regeneration for the recovery of function. The evaluation of drug metabolism during liver regeneration is also necessary because liver dysfunction is generally observed after the operation. Here, we investigated the influence of a purified diet (AIN-93G) on liver regeneration and changes in the mRNA expression of several cytochrome P450 (CYP) isoforms in the liver and small intestine using a two-thirds partial hepatectomy (PH) mouse model fed with a standard diet (MF) and a purified diet. Liver regeneration was significantly delayed in the purified diet group relative to that in the standard diet group. The liver Cyp2c55 and Cyp3a11 expression was increased at 3 day after PH especially in the purified diet group. Bile acid may partly cause the differences in liver regeneration and CYP expression between two types of diets. On the other hand, Cyp3a13 expression in the small intestine was transiently increased at day 1 after PH in both diet groups. The findings suggest that compensatory induction of the CYP expression occurred in the small intestine after attenuation of drug metabolism potential in the liver. The present results highlight the importance of the relationship between liver regeneration, drug metabolism, and exogenous factors for the effective treatment, including surgery and medication, in patients after liver resection or transplantation.

Endoscopic versus percutaneous biliary drainage in patients with resectable perihilar cholangiocarcinoma: a multicentre, randomised controlled trial

BACKGROUND

In patients with resectable perihilar cholangiocarcinoma, biliary drainage is recommended to treat obstructive jaundice and optimise the clinical condition before liver resection. Little evidence exists on the preferred initial method of biliary drainage. We therefore investigated the incidence of severe drainage-related complications of endoscopic biliary drainage or percutaneous transhepatic biliary drainage in patients with potentially resectable perihilar cholangiocarcinoma.

METHODS

We did a multicentre, randomised controlled trial at four academic centres in the Netherlands. Patients who were aged at least 18 years with potentially resectable perihilar cholangiocarcinoma requiring major liver resection, and biliary obstruction of the future liver remnant (defined as a bilirubin concentration of >50 μmol/L [2·9 mg/dL]), were randomly assigned (1:1) to receive endoscopic biliary drainage or percutaneous transhepatic biliary drainage through the use of computer-generated allocation. Randomisation, done by the trial coordinator, was stratified for previous (attempted) biliary drainage, the extent of bile duct involvement, and enrolling centre. Patients were enrolled by clinicians of the participating centres. The primary outcome was the number of severe complications between randomisation and surgery in the intention-to-treat population. The trial was registered at the Netherlands National Trial Register, number NTR4243.

FINDINGS

From Sept 26, 2013, to April 29, 2016, 261 patients were screened for participation, and 54 eligible patients were randomly assigned to endoscopic biliary drainage (n=27) or percutaneous transhepatic biliary drainage (n=27). The study was prematurely closed because of higher mortality in the percutaneous transhepatic biliary drainage group (11 [41%] of 27 patients) than in the endoscopic biliary drainage group (three [11%] of 27 patients; relative risk 3·67, 95% CI 1·15-11·69; p=0·03). Three of the 11 deaths among patients in the percutaneous transhepatic biliary drainage group occurred before surgery. The proportion of patients with severe preoperative drainage-related complications was similar between the groups (17 [63%] patients in the percutaneous transhepatic biliary drainage group vs 18 [67%] in the endoscopic biliary drainage group; relative risk 0·94, 95% CI 0·64-1·40). 16 (59%) patients in the percutaneous transhepatic biliary drainage group and ten (37%) patients in the endoscopic biliary drainage group developed preoperative cholangitis (p=0·1). 15 (56%) patients required additional percutaneous transhepatic biliary drainage after endoscopic biliary drainage, whereas only one (4%) patient required endoscopic biliary drainage after percutaneous transhepatic biliary drainage.

INTERPRETATION

The study was prematurely stopped because of higher all-cause mortality in the percutaneous transhepatic biliary drainage group. Post-drainage complications were similar between groups, but the data should be interpreted with caution because of the small sample size. The results call for further prospective studies and reconsideration of indications and strategy towards biliary drainage in this complex disease.

FUNDING

Dutch Cancer Foundation.

Hepatic Regeneration and Reno-Protection by Fish oil, Nigella sativa Oil and Combined Fish Oil/Nigella sativa Volatiles in CCl4 Treated Rats

The aim of the present research was to investigate the effect of fish oil, crude Nigella sative oil and combined fish oil/Nigella sative volatile oil as hepato-regenerative and renal protective supplements. The oils were administered as emulsions to rat model with liver injury induced by CCl₄. Plasma activities of transaminases (AST and ALT) were evaluated as liver function indicators, while plasma creatinine and urea and creatinine clearance were determined as markers of kidney function. Plasma malondialdehyde (MDA), nitrite (NO) and tumor necrosis factor-α (TNF-α) were estimated to assess the exposure to oxidative stress and subsequent inflammation. Liver fat was extracted and their fatty acids´ methyl esters were determined using gas chromatography. Results showed that plasma activities of AST and ALT were significantly higher in CCl₄ control group compared to control healthy group. Plasma levels of creatinine and urea increased significantly in CCl₄ control, while creatinine clearance was reduced significantly in the same group. All rat treated groups given the three oil emulsions showed improvement in liver function pointing to the initiation of liver regeneration. The combination of fish oil/Nigella sative volatiles showed the most promising regenerative activity. Oxidative stress and inflammation which were increased significantly in CCl₄ control group showed improvement on administration of the three different oil emulsions. Fatty acids methyl ester of liver fat revealed that rats treated with fish oil/Nigella sative volatile oil presented the highest content of unsaturated fatty acids (45.52% ± 0.81) while fish oil showed the highest saturated fatty acids (53.28% ± 1.68). Conclusion; Oral administration of oil emulsions of native fish oil, Nigella sative crude oil and combined fish oil/Nigella sative volatile oil reduced liver and kidney injury in rat model of CCl₄ through exerting anti-inflammatory and antioxidant activity. Fish oil/Nigella sative volatile oil emulsion was the most promising hepato-regenerative and reno-protective formula among the different groups.

Functional shift with maintained regenerative potential following portal vein ligation

Selective portal vein ligation (PVL) allows the two-stage surgical resection of primarily unresectable liver tumours by generating the atrophy and hypertrophy of portally ligated (LL) and non-ligated lobes (NLL), respectively. To evaluate critically important underlying functional alterations, present study characterised in vitro and vivo liver function in male Wistar rats (n = 106; 210-250 g) before, and 24/48/72/168/336 h after PVL. Lobe weights and volumes by magnetic resonance imaging confirmed the atrophy-hypertrophy complex. Proper expression and localization of key liver transporters (Ntcp, Bsep) and tight junction protein ZO-1 in isolated hepatocytes demonstrated constantly present viable and well-polarised cells in both lobes. In vitro taurocholate and bilirubin transport, as well as in vivo immunohistochemical Ntcp and Mrp2 expressions were bilaterally temporarily diminished, whereas LL and NLL structural acinar changes were divergent. In vivo bile and bilirubin-glucuronide excretion mirrored macroscopic changes, whereas serum bilirubin levels remained unaffected. In vivo functional imaging (indocyanine-green clearance test; ^99mTc-mebrofenin hepatobiliary scintigraphy; confocal laser endomicroscopy) indicated transitionally reduced global liver uptake and -excretion. While LL functional involution was permanent, NLL uptake and excretory functions recovered excessively. Following PVL, functioning cells remain even in LL. Despite extensive bilateral morpho-functional changes, NLL functional increment restores temporary declined transport functions, emphasising liver functional assessment.

Bioenergetic adaptations of the human liver in the ALPPS procedure - how liver regeneration correlates with mitochondrial energy status

BACKGROUND

The Associating Liver Partition and Portal Ligation for Staged Hepatectomy (ALPPS) depends on a significant inter-stages kinetic growth rate (KGR). Liver regeneration is highly energy-dependent. The metabolic adaptations in ALPPS are unknown.

AIMS

i) Assess bioenergetics in both stages of ALPPS (T1 and T2) and compare them with control patients undergoing minor (miHp) and major hepatectomy (MaHp), respectively; ii) Correlate findings in ALPPS with volumetric data; iii) Investigate expression of genes involved in liver regeneration and energy metabolism.

METHODS

Five patients undergoing ALPPS, five controls undergoing miHp and five undergoing MaHp. Assessment of remnant liver bioenergetics in T1, T2 and controls. Analysis of gene expression and protein content in ALPPS.

RESULTS

Mitochondrial function was worsened in T1 versus miHp; and in T2 versus MaHp (p < 0.05); but improved from T1 to T2 (p < 0.05). Liver bioenergetics in T1 strongly correlated with KGR (p < 0.01). An increased expression of genes associated with liver regeneration (STAT3, ALR) and energy metabolism (PGC-1α, COX, Nampt) was found in T2 (p < 0.05).

CONCLUSION

Metabolic capacity in ALPPS is worse than in controls, improves between stages and correlates with volumetric growth. Bioenergetic adaptations in ALPPS could serve as surrogate markers of liver reserve and as target for energetic conditioning.

Animal Models for Associating Liver Partition and Portal Vein Ligation for Staged Hepatectomy (ALPPS): Achievements and Future Perspectives

Background: Since 2012, Associated Liver Partition and Portal vein ligation for Staged hepatectomy (ALPPS) has been standing in the limelight of modern liver surgery and numerous questions have been raised regarding this novel approach. On the one hand, ALPPS has proved to be a valuable method in the treatment of hepatic tumors, while on the other hand, there are many controversies, such as high mortality and morbidity rates. Further surgical research is essential for a better understanding of underlying mechanisms and for enhancing patient safety. Summary: Until recently, only 8 animal models have been created with the purpose to mimic ALPPS-induced liver regeneration. From these 7 are rodent (6 rat and 1 mouse) models, while only 1 is a large animal model, which uses pigs. In case of rodent models, portal flow deprivation of 75-90% is achieved via portal vein ligation leaving only the right (20-25%) or left median (10-15%) lobes portally perfused, while liver splitting in general is carried out positioned according to the falciform ligament. As for the swine model, the left lateral and medial lobes (70-75% of total liver volume) are portally ligated, and the right lateral lobe (accounting for 20-24% of the parenchyma) is partially resected in order to reach critical liver volume. Each model is capable of reproducing the accelerated liver regeneration seen in human cases. However, all species have significantly different liver anatomy compared with the human anatomic situation, making clinical translation somewhat difficult. Key Messages: Unfortunately, there are no perfect animal models available for ALPPS research. Small animal models are inexpensive and well suited for basic research, but may only provide limited translational potential to humans. Clinically large animal models may provide more relevant data, but currently no suitable one exists.