Hepatic regeneration and functional recovery following partial liver resection in an experimental model of hepatic steatosis treated with omega-3 fatty acids

Effects of Omega-3 Polyunsaturated Fatty Acids, Docosahexaenoic Acid and Eicosapentaenoic Acid, on Post-Surgical Complications in Surgical Trauma Patients: Mechanisms, Nutrition, and Challenges

This paper aims to provide an in-depth review of the specific outcomes associated with omega-3 polyunsaturated fatty acids (PUFAs), focusing on their purported effects on post-surgical complications in trauma patients. A comprehensive investigation of omega-3 polyunsaturated fatty acids was conducted until February 2023 using the PubMed database. Surgical trauma is characterized by a disruption in immune response post surgery, known to induce systemic inflammation. Omega-3 PUFAs are believed to offer potential improvements in multiple post-surgical complications because of their anti-inflammatory and antioxidant properties. Inconsistent findings have emerged in the context of cardiac surgeries, with the route of administration playing a mediating role in these outcomes. The effects of omega-3 PUFAs on post-operative atrial fibrillation have exhibited variability across various studies. Omega-3 PUFAs have demonstrated positive effects in liver surgery outcomes and in patients with acute respiratory distress syndrome. Omega-3 is suggested to offer potential benefits, particularly in the perioperative care of patients undergoing traumatic procedures. Incorporating omega-3 in such cases is hypothesized to contribute to a reduction in certain surgical outcomes, such as hospitalization duration and length of stay in the intensive care unit. Therefore, comprehensive assessments of adverse effects can aid in identifying the presence of subtle or inconspicuous side effects associated with omega-3.

Dysfunctional Cori and Krebs cycle and inhibition of lactate transporters constitute a mechanism of primary nonfunction of fatty liver allografts

Orthotopic liver transplantation (OLT) is a lifesaving procedure. However, grafts may fail due to primary nonfunction (PNF). In the past, we demonstrated PNFs to be mainly associated with fatty allografts, and given its unpredictable nature, the development of a disease model is urgently needed. In an effort to investigate mechanism of fatty allograft-associated PNFs, we induced fatty liver disease in donor animals by feeding rats a diet deficient in methionine and choline (MCD). We performed OLT with allografts of different grades of hepatic steatosis and compared the results to healthy ones. We assessed liver function by considering serum biochemistries, and investigated genome wide responses following OLT of healthy and fatty allograft-associated PNFs. Furthermore, we performed immunohistochemistry to evaluate markers of oxidative stress and reperfusion injury, inflammation, glycolysis and gluconeogenesis, lactate transport, and its utilization as part of the Cori cycle. Strikingly, PNFs are strictly lipid content dependent. Nonetheless, a fat content of ≤17% and an increase in the size of hepatocytes of ≤11% (ballooning) greatly improved outcome of OLTs and the hepatic microcirculation. Mechanistically, PNFs arise from a dysfunctional Cori cycle with complete ablation of the lactate transporter SLC16A1. Thus, lipid-laden hepatocytes fail to perform gluconeogenesis via lactate reutilization, and the resultant hyperlactatemia and lactic acidosis causes cardiac arrhythmogenicity and death. Furthermore, the genomic and immunohistochemistry investigations underscore a dysfunctional Krebs cycle with impaired energy metabolism in lipid-burdened mitochondria. Together, we show fatty allografts to be highly vulnerable towards ischemia/reperfusion-injury, and stabilizing the Cori cycle is of critical importance to avert PNFs.

Effect of Hepatic Pathology on Liver Regeneration: The Main Metabolic Mechanisms Causing Impaired Hepatic Regeneration

Liver regeneration has been studied for many decades, and the mechanisms underlying regeneration of normal liver following resection are well described. However, no less relevant is the study of mechanisms that disrupt the process of liver regeneration. First of all, a violation of liver regeneration can occur in the presence of concomitant hepatic pathology, which is a key factor reducing the liver's regenerative potential. Understanding these mechanisms could enable the rational targeting of specific therapies to either reduce the factors inhibiting regeneration or to directly stimulate liver regeneration. This review describes the known mechanisms of normal liver regeneration and factors that reduce its regenerative potential, primarily at the level of hepatocyte metabolism, in the presence of concomitant hepatic pathology. We also briefly discuss promising strategies for stimulating liver regeneration and those concerning methods for assessing the regenerative potential of the liver, especially intraoperatively.

Clearing Steatosis Prior to Liver Surgery for Colorectal Metastasis: A Narrative Review and Case Illustration

Over recent years, non-alcoholic fatty liver disease (NAFLD) has become the most common liver disorder in the developed world, accounting for 20% to 46% of liver abnormalities. Steatosis is the hallmark of NAFLD and is recognized as an important risk factor for complication and death after general surgery, even more so after liver resection. Similarly, liver steatosis also impacts the safety of live liver donation and transplantation. We aim to review surgical outcomes after liver resection for colorectal metastases in patients with steatosis and discuss the most common pre-operative strategies to reduce steatosis. Finally, as illustration, we report the favorable effect of a low-caloric, hyper-protein diet during a two-stage liver resection for colorectal metastases in a patient with severe steatosis.

Exercise, Diet and Sleeping as Regenerative Medicine Adjuvants: Obesity and Ageing as Illustrations

Regenerative medicine uses the biological and medical knowledge on how the cells and tissue regenerate and evolve in order to develop novel therapies. Health conditions such as ageing, obesity and cancer lead to an impaired regeneration ability. Exercise, diet choices and sleeping pattern have significant impacts on regeneration biology via diverse pathways including reducing the inflammatory and oxidative components. Thus, exercise, diet and sleeping management can be optimized towards therapeutic applications in regenerative medicine. It could allow to prevent degeneration, optimize the biological regeneration and also provide adjuvants for regenerative medicine.

Risk factors of delayed recovery from general anesthesia in patients undergoing radical biliary surgery: What can we prevent

Delayed recovery (DR) is very commonly seen in the patients undergoing laparoscopic radical biliary surgery, we aimed to investigate the potential risk factors of DR in the patients undergoing radical biliary surgery, to provide evidences into the management of DR.Patients who underwent radical biliary surgery from January 1, 2018 to August 31, 2020 were identified. The clinical characteristics and treatment details of DR and no-DR patients were compared and analyzed. Multivariable logistic regression analyses were conducted to identify the potential influencing factors for DR in patients with laparoscopic radical biliary surgery.We included a total of 168 patients with laparoscopic radical biliary surgery, the incidence of postoperative DR was 25%. There were significant differences on the duration of surgery, duration of anesthesia, and use of intraoperative combined sevoflurane inhalation (all P < .05), and there were not significant differences on American Society of Anesthesiologists, New York Heart Association, tumor-lymph node- metastasis, and estimated blood loss between DR group and control group (all P > .05). Multivariable logistic regression analyses indicated that age ≥70 years (odd ratio [OR] 1.454, 95% confidence interval [CI] 1.146-1.904), body mass index ≥25 kg/m2 (OR 1.303, 95% CI 1.102-1.912), alcohol drinking (OR 2.041, 95% CI 1.336-3.085), smoking (OR 1.128, 95% CI 1.007-2.261), duration of surgery ≥220 minutes (OR 1.239, 95% CI 1.039-1.735), duration of anesthesia ≥230 minutes (OR 1.223, 95% CI 1.013-1.926), intraoperative combined sevoflurane inhalation (OR 1.207, 95% CI 1.008-1.764) were the independent risk factors for DR in patients with radical biliary surgery (all P < .05).It is clinically necessary to take early countermeasures against various risk factors to reduce the occurrence of DR, and to improve the prognosis of patients.

Perioperative omega-3 fatty acids for liver surgery: A meta-analysis of randomized controlled trials

INTRODUCTION

The effect of perioperative omega-3 fatty acids for liver surgery remained controversial. We conducted a systematic review and meta-analysis to explore the influence of omega-3 fatty acids versus placebo in patients undergoing liver surgery.

METHODS

We have searched PubMed, EMbase, Web of science, EBSCO, and Cochrane library databases through May 2020, and included randomized controlled trials (RCTs) assessing the effect of omega-3 fatty acids versus placebo for liver surgery. This meta-analysis was performed using the random-effect model.

RESULTS

Five RCTs were included in the meta-analysis. Overall, compared with control group for liver surgery, omega-3 fatty acids were associated with substantially reduced incidence of infection (odd ratio [OR]=0.56; 95% confidence interval [CI] =0.34-0.91; P = .02), but revealed no remarkable influence on complications (OR = 0.60; 95% CI = 0.29-1.24; P = .17), mortality (OR = 0.76; 95% CI = 0.06-9.37; P = .83), liver failure (OR = 0.72; 95% CI = 0.10 to 5.00; P = 0.74), biliary leakage (OR=1.24; 95% CI = 0.41 to 3.76; P = .70), bleeding (OR = 1.76; 95% CI = 0.63-4.95; P = .28), or ileus (OR = 0.39; 95% CI = 0.07-2.05; P = .27).

CONCLUSION

Perioperative omega-3 fatty acids may be beneficial to reduce the incidence of infection after liver surgery.

Unaltered Liver Regeneration in Post-Cholestatic Rats Treated with the FXR Agonist Obeticholic Acid

In a previous study, obeticholic acid (OCA) increased liver growth before partial hepatectomy (PHx) in rats through the bile acid receptor farnesoid X-receptor (FXR). In that model, OCA was administered during obstructive cholestasis. However, patients normally undergo PHx several days after biliary drainage. The effects of OCA on liver regeneration were therefore studied in post-cholestatic Wistar rats. Rats underwent sham surgery or reversible bile duct ligation (rBDL), which was relieved after 7 days. PHx was performed one day after restoration of bile flow. Rats received 10 mg/kg OCA per day or were fed vehicle from restoration of bile flow until sacrifice 5 days after PHx. Liver regeneration was comparable between cholestatic and non-cholestatic livers in PHx-subjected rats, which paralleled liver regeneration a human validation cohort. OCA treatment induced ileal Fgf15 mRNA expression but did not enhance post-PHx hepatocyte proliferation through FXR/SHP signaling. OCA treatment neither increased mitosis rates nor recovery of liver weight after PHx but accelerated liver regrowth in rats that had not been subjected to rBDL. OCA did not increase biliary injury. Conclusively, OCA does not induce liver regeneration in post-cholestatic rats and does not exacerbate biliary damage that results from cholestasis. This study challenges the previously reported beneficial effects of OCA in liver regeneration in cholestatic rats.

Perioperative omega-3 fatty acids fail to confer protection in liver surgery: Results of a multicentric, double-blind, randomized controlled trial

BACKGROUND & AIMS

In a variety of animal models, omega-3 polyunsaturated fatty acids (Ω3-FAs) conferred strong protective effects, alleviating hepatic ischemia/reperfusion injury and steatosis, as well as enhancing regeneration after major tissue loss. Given these benefits along with its safety profile, we hypothesized that perioperative administration of Ω3-FAs in patients undergoing liver surgery may ameliorate the postoperative course. The aim of this study was to investigate the perioperative use of Ω3-FAs to reduce postoperative complications after liver surgery.

METHODS

Between July 2013 and July 2018, we carried out a multicentric, double-blind, randomized, placebo-controlled trial designed to test whether 2 single intravenous infusions of Omegaven® (Ω3-FAs) vs. placebo may decrease morbidity. The primary endpoints were postoperative complications by severity (Clavien-Dindo classification) integrated within the comprehensive complication index (CCI).

RESULTS

A total of 261 patients (132 in the Omegaven and 129 in the placebo groups) from 3 centers were included in the trial. Most cases (87%, n = 227) underwent open liver surgery and 56% (n = 105) were major resections (≥3 segments). In an intention-to-treat analysis including the dropout cases, the mortality rate was 4% and 2% in the Omegaven and placebo groups (odds ratio0.40;95% CI 0.04-2.51; p = 0.447), respectively. Any complications and major complications (Clavien-Dindo ≥ 3b) occurred in 46% vs. 43% (p = 0.709) and 12% vs. 10% (p = 0.69) in the Omegaven and placebo groups, respectively. The mean CCI was 17 (±23) vs.14 (±20) (p = 0.417). An analysis excluding the dropouts provided similar results.

CONCLUSIONS

The routine perioperative use of 2 single doses of intravenous Ω3-FAs (100 ml Omegaven) cannot be recommended in patients undergoing liver surgery (Grade A recommendation).

LAY SUMMARY

Despite strong evidence of omega-3 fatty acids having liver-directed, anti-inflammatory and pro-regenerative action in various rodent models, 2 single omega-3 fatty acid infusions given to patients before and during liver surgery failed to reduce complications. Because single omega-3 fatty acid infusions failed to confer liver protection in this trial, they cannot currently be recommended.

TRIAL REGISTRATION

ClinicalTrial.gov: ID: NCT01884948; Institution Ethical Board Approval: KEK-ZH-Nr. 2010-0038; Swissmedic Notification: 2012DR3215.

New Insights into the Liver-Visceral Adipose Axis During Hepatic Resection and Liver Transplantation

In the last decade, adipose tissue has emerged as an endocrine organ with a key role in energy homeostasis. In addition, there is close crosstalk between the adipose tissue and the liver, since pro- and anti-inflammatory substances produced at the visceral adipose tissue level directly target the liver through the portal vein. During surgical procedures, including hepatic resection and liver transplantation, ischemia–reperfusion injury induces damage and regenerative failure. It has been suggested that adipose tissue is associated with both pathological or, on the contrary, with protective effects on damage and regenerative response after liver surgery. The present review aims to summarize the current knowledge on the crosstalk between the adipose tissue and the liver during liver surgery. Therapeutic strategies as well as the clinical and scientific controversies in this field are discussed. The different experimental models, such as lipectomy, to evaluate the role of adipose tissue in both steatotic and nonsteatotic livers undergoing surgery, are described. Such information may be useful for the establishment of protective strategies aimed at regulating the liver–visceral adipose tissue axis and improving the postoperative outcomes in clinical liver surgery.

Dietary chia seeds (Salvia hispanica) improve acute dyslipidemia and steatohepatitis in rats

Chia seeds (Salvia hispanica L.) are rich in omega fatty acids. Dyslipidemia and steatohepatitis are diseases that require effective treatments in obese and non-obese patients. The aim was to evaluate the effect of chia intake on acute tyloxapol (TI)-induced dyslipidemia, on acute carbon tetrachloride (TC)-induced steatohepatitis, and on mixed damage (TC+TI) in non-obese rats. Four experimental groups were fed for 4 weeks a diet with established rodent food (DE), and four groups were fed a diet with 15% added chia (DC). Plasma samples were analyzed for total cholesterol, triglycerides, glucose, biochemical liver damage markers, and tumor necrosis factor-α (TNF-α). Liver samples were used to quantify glycogen, catalase, lipid peroxidation, and TNF-α. A histopathological analysis was performed. DC intake partially or totally prevented steatohepatitis, and reduced lipids in the dyslipidemic groups. The hypolipidemic and hepatoprotective effects of chia may be correlated to its high content of α-linolenic acid (omega-3) and phenolics. PRACTICAL APPLICATIONS: Metabolic syndrome is associated with non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH), which are currently the most common causes of chronic liver disease, cirrhosis, and hepatocellular carcinoma (HCC) worldwide. Dyslipidemia is a significant risk factor for NAFLD and NASH. Non-obese patients may have NAFLD or NASH. Metabolic syndrome and dyslipidemia are more strongly associated with NAFLD in non-obese than in obese patients. This is the first study evaluating the hypolipidemic and hepatoprotective effects of chia seed intake on acute dyslipidemia and/or steatohepatitis caused by the individual or combined administration of the inducers tyloxapol and carbon tetrachloride, respectively, in non-obese rats. The pharmacological effects of dietary chia are correlated to its high content of omega-3 and omega-6 (1:1), protein, dietary fiber, and phenolics. The results suggest that inclusion of chia in diets of non-obese patients with dyslipidemia and/or NAFLD/NASH may improve their health state and preventing cirrhosis or HCC.

Preventive effect of omega-3 fatty acids in a rat model of stress-induced liver injury

Omega-3 fatty acids are gaining attention as a therapeutic agent of many diseases. Their protective effect in a variety of diseases has been demonstrated. To the best of our knowledge, this is the first study on omega-3 fatty acids related to acute cold-restraint stress (CRS) induced hepatic dysfunction in rats. Forty adult male Sprague-Dawley albino rats were used and classified into: control, omega-3 group, each rat was pretreated with omega-3 fatty acids; CRS group, rats were subjected to acute CRS for 6 hr; and CRS group pretreated with omega-3 fatty acids. Serum was obtained to determine corticosterone (CORT), alanine aminotransferase (ALT), aspartate aminotransferase (AST), and tumor necrosis factor-α (TNF-α) levels. Hepatic malondialdehyde (MDA) and total antioxidant capacity (TAC) levels were measured. Also, liver tissues were taken for histological examination and immunohistochemical assessment of the apoptotic marker, caspase-3. Results showed that pretreatment of stressed rats with omega-3 fatty acids led to significant decrease in hepatic MDA and increase in TAC levels. They reduced serum levels of CORT, ALT, AST, and TNF-α. Also, they improved liver damage and suppressed hepatic caspase-3 expression. In conclusion, pretreatment of stressed rats with omega-3 fatty acids has ameliorated stress-induced liver damage due to their antioxidant, anti-inflammatory, and antiapoptotic effects. So, they can be used to minimize stress complications on the liver.

Use of Steatotic Grafts in Liver Transplantation: Current Status

In the field of liver transplantation, the demand for adequate allografts greatly exceeds the supply. Therefore, expanding the donor pool to match the growing demand is mandatory. The present review summarizes current knowledge of the pathophysiology of ischemia/reperfusion injury in steatotic grafts, together with recent pharmacological approaches aimed at maximizing the utilization of these livers for transplantation. We also describe the preclinical models currently available to understand the molecular mechanisms controlling graft viability in this specific type of donor, critically discussing the heterogeneity in animal models, surgical methodology, and therapeutic interventions. This lack of common approaches and interventions makes it difficult to establish the pathways involved and the relevance of isolated discoveries, as well as their transferability to clinical practice. Finally, we discuss how new therapeutic strategies developed from experimental studies are promising but that further studies are warranted to translate them to the bedside.

Effect of ω-3 polyunsaturated fatty acids on liver function and inflammatory reaction in patients undergoing hepatectomy: a systematic review and meta-analysis of randomized control trials

Several studies have investigated the relationship between ω-3 polyunsaturated fatty acids (PUFAs) administration and liver function and inflammatory reaction in patients undergoing liver resection, but the results remain conflicting and inconclusive. Areas covered: In this meta-analysis, a relevant database search was performed to retrieve all the randomized controlled trials (RCTs) exploring the effect of ω-3 PUFAs administration in patients undergoing hepatectomy until the end of April 2018. A random effect model was used to conduct this meta-analysis with RevMan 5.3.5 software. The quality of evidence for each postoperative outcome was assessed using the GRADEpro analysis. Expert opinion: 4 RCTs including 553 patients (277 with and 276 without ω-3 PUFAs) were identified. ω-3 PUFAs significantly reduced alanine aminotransferase [Mean difference (MD): -68.82, 95% confidence interval (CI): -108.55 to - 29.08; p = 0.0007]; aspartate aminotransferase (MD: -64.92, 95% CI: -112.87 to -16.98; p = 0.008), white blood cell count (MD: -1.22, 95% CI: -2.15 to -0.29; p = 0.01) and increased the level of pre-albumin on postoperative day 3 (MD: 10.42, 95% CI: 4.84 to 15.99; p = 0.0002). The results indicate that ω-3 PUFAs administration has a positive impact on the liver function and inflammatory reaction in patients undergoing liver resection.

Omega-3 fatty acid supplementation does not influence liver regeneration in rats after partial hepatectomy

Aim of the study

In the initiation of liver regeneration, multiple stimulatory and inhibitory factors participate. In this study, we aimed to evaluate the effects of omega-3 fatty acids on liver regeneration after 30% partial hepatectomy in rats.

Material and methods

A total of 14 male Wistar Albino rats were included in this study. The animals were randomly allocated to two groups: the control group (n = 7) and the omega-3 group (n = 7). Rats in the control group were fed a standard rat chow and rats in the omega-3 group received 10 mg/kg/day omega-3 supplementation in addition to normal rat chow in the perioperative period. Rats were investigated seven days after 1/3 partial hepatectomy by liver weight change and hepatocyte proliferation.

Results

The mean liver regeneration rate was found to be slightly higher (p = 0.061) in the omega-3 group compared the control group. In addition, no significant difference was observed regarding binuclear hepatocyte ratio in pericentral and periportal areas between the two groups. However, livers from rats given omega-3 supplementation have less inflammatory cellular infiltrate in the portal space than livers from the control group.

Conclusions

Supplementation with omega-3 fatty acids showed no influence on the liver regeneration in rats undergoing 1/3 partial hepatectomy.

The impact of steatosis on liver regeneration

Alcoholic and non-alcoholic fatty liver diseases are the leading causes of cirrhosis in Western countries. These chronic liver diseases share common pathological features ranging from steatosis to steatohepatitis. Fatty liver is associated with primary liver graft dysfunction, a higher incidence of complications/mortality after surgery, in correlation with impaired liver regeneration. Liver regeneration is a multistep process including a priming phase under the control of cytokines followed by a growth factor receptor activation phase leading to hepatocyte proliferation. This process ends when the initial liver mass is restored. Deficiency in epidermal growth factor receptor (EGFR) liver expression, reduced expression of Wee1 and Myt1 kinases, oxidative stress and alteration in hepatocyte macroautophagy have been identified as mechanisms involved in the defective regeneration of fatty livers. Besides the mechanisms, we will also discuss in this review various treatments that have been investigated in the reversal of the regeneration defect, for example, omega-3 fatty acids, pioglitazone, fibroblast growth factor (FGF)19-based chimeric molecule or growth hormone (GH). Since dysbiosis impedes liver regeneration, targeting microbiota could also be an interesting therapeutic approach.

FXR agonist obeticholic acid induces liver growth but exacerbates biliary injury in rats with obstructive cholestasis

Cholestasis impairs liver regeneration following partial liver resection (PHx). Bile acid receptor farnesoid X-receptor (FXR) is a key mediator of liver regeneration. The effects of FXR agonist obeticholic acid (OCA) on liver (re)growth were therefore studied in cholestatic rats. Animals underwent sham surgery or reversible bile duct ligation (rBDL). PHx with concurrent internal biliary drainage was performed 7 days after rBDL. Animals were untreated or received OCA (10 mg/kg/day) per oral gavage from rBDL until sacrifice. After 7 days of OCA treatment, dry liver weight increased in the rBDL + OCA group, indicating OCA-mediated liver growth. Enhanced proliferation in the rBDL + OCA group prior to PHx concurred with a rise in Ki67-positive hepatocytes, elevated hepatic Ccnd1 and Cdc25b expression, and an induction of intestinal fibroblast growth factor 15 expression. Liver regrowth after PHx was initially stagnant in the rBDL + OCA group, possibly due to hepatomegaly prior to PHx. OCA increased hepatobiliary injury markers during BDL, which was accompanied by upregulation of the bile salt export pump. There were no differences in histological liver injury. In conclusion, OCA induces liver growth in cholestatic rats prior to PHx but exacerbates biliary injury during cholestasis, likely by forced pumping of bile acids into an obstructed biliary tree.

DHA attenuates hepatic ischemia reperfusion injury by inhibiting pyroptosis and activating PI3K/Akt pathway

Hepatic ischemia reperfusion (I/R) injury is very common in liver transplantation and major liver surgeries and may cause liver failure or even death. Docosahexaenoic acid (DHA) has displayed activities in reducing oxidative stress and inflammatory reaction in many disorders. In the present study, we investigated the protective effects of DHA against I/R-induced injury and the underlying mechanisms. Here, we show that DHA protected hepatic I/R injury by reducing aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels and decreasing the oxidative stress in liver tissues. The viability of Buffalo rat liver (BRL) cells was reduced by hypoxia/restoration (H/R) but restored by DHA. DHA significantly downregulated the expression of pyroptosis-related proteins including NLR pyrin domain containing 3 (NLRP3), apoptotic speck-like protein containing CARD (ASC) and cleaved caspase-1 and reduced the secretion of pro-inflammatory cytokines. The above results were supported by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining. However, incubation with LY294002, a specific inhibitor of phosphatidylinositol-3-kinase (PI3K), abolished the effects of DHA, since it increased the expression of cleaved caspase-1 and the production of inflammatory cytokines. The present results have demonstrated that DHA ameliorated I/R-induced injury by inhibiting pyroptosis of hepatocytes induced in liver I/R injury in vivo and in vitro through the PI3K/Akt pathway, providing a potential therapeutic option to prevent liver injury by I/R.

Preserved liver regeneration capacity after partial hepatectomy in rats with non-alcoholic steatohepatitis

AIM

To evaluate the liver regeneration capacity (LRC) after partial hepatectomy (PH) in experimental non-alcoholic steatohepatitis (NASH).

METHODS

Fifty-four female rats were fed a high-fat, high-cholesterol diet (HFCD, 65% fat, 1% cholesterol) or standard diet (STD) for 16 wk. A 70% PH was performed and the animals were euthanised before PH or 2 or 5 d post-PH. LRC was evaluated using: The total number of Ki-67 positive hepatocytes in the caudate lobe, N(Ki-67, lobe) evaluated in a stereology-based design, the regenerated protein ratio (RPR), prothrombin-proconvertin ratio (PP), and mRNA expression of genes related to regeneration.

RESULTS

The HFCD NASH model showed significant steatosis with ballooning and inflammation, while no fibrosis was present. Mortality was similar in HFCD and STD animals following PH. HFCD groups were compared to respective STD groups and HFCD animals had a significantly elevated alanine transaminase at baseline (P < 0.001), as well as a significantly elevated bilirubin at day 2 after PH (P < 0.05). HFCD animals had a higher N(Ki-67, lobe) at baseline, (P < 0.0001), day 2 after PH (P = 0.06) and day 5 after PH (P < 0.025). We found no significant difference in RPR or PP neither 2 or 5 d post-PH. Expression of liver regeneration genes (e.g., hepatic growth factor) was higher at both day 2 and 5 post-PH in HFCD groups (P < 0.05).

CONCLUSION

NASH rats had a preserved LRC after hepatectomy when compared to STD rats. The methods and models of NASH are essential in understanding and evaluating LRC.

Pretreatment with intravenous fish oil reduces hepatic ischemia reperfusion injury in a murine model

BACKGROUND

Ischemia reperfusion injury is a barrier to liver surgery and transplantation, particularly for steatotic livers. The purpose of this study was to determine if pretreatment with a single dose of intravenous fish oil decreases hepatic ischemia reperfusion injury and improves recovery of injured livers.

METHODS

Sixty adult male C57BL/6 mice received 1 g/kg intravenous fish oil (Omegaven, Fresenius Kabi) or isovolumetric 0.9% NaCl (saline) via tail vein 1 hour before 30 minutes of 70% hepatic ischemia. Animals were killed 4, 8, or 24 hours postreperfusion, and livers were harvested for histologic analysis.

RESULTS

Four hours postreperfusion, saline-treated livers demonstrated marked ischemia diffusely around the central veins, while intravenous fish oil-treated livers demonstrated only patchy necrosis with intervening normal parenchyma. Eight hours postreperfusion, all livers demonstrated pale areas of cell loss with surrounding regenerating hepatocytes. Ki67 staining confirmed 14.4/10 high-powered field (95% confidence interval, 3.2-25.6) more regenerating hepatocytes around areas of necrosis in intravenous fish oil-treated livers. Twenty-four hours postreperfusion, all livers demonstrated patchy areas of necrosis, with an 89% (95% confidence interval, 85-92) decrease in the area of necrosis in intravenous fish oil-treated livers.

CONCLUSION

Intravenous fish oil treatment prior to hepatic ischemia reperfusion injury decreased the area of hepatic necrosis and increased hepatocyte regeneration compared to saline treatment in a mouse model.

Hypothermic oxygenated perfusion (HOPE) for fatty liver grafts in rats and humans

BACKGROUND & AIMS

Pretreatment of marginal organs by perfusion is a promising opportunity to make more organs available for transplantation. Protection of human donation after cardiac death (DCD) livers by a novel machine perfusion technique, hypothermic oxygenated perfusion (HOPE), was recently established. Herein, we tested whether HOPE is also useful for fatty liver grafts, using a rodent transplant model.

METHODS

Rats were fed over three weeks with a special methionine-choline-deficient diet (MCDD) to induce severe hepatic macrosteatosis (≥60%). Afterwards, livers were transplanted with either minimal or 12h cold storage. Additional liver grafts were treated after 12h cold storage with 1h HOPE before transplantation. Graft injury after orthotopic liver transplantation (OLT) was assessed in terms of oxidative stress, damage-associated molecular patterns release, toll-like receptor-4 activation, cytokine release, endothelial activation, and the development of necrosis and fibrosis.

RESULTS

Implantation of cold stored macrosteatotic liver grafts induced massive reperfusion injury after OLT, compared to controls (non-fatty livers). HOPE treatment after cold storage failed to change the degree of steatosis itself, but markedly decreased reperfusion injury after OLT, as detected by less oxidative stress, less nuclear injury, less Kupffer- and endothelial cell activation, as well as less fibrosis within one week after OLT. Protective effects were lost in the absence of oxygen in the HOPE perfusate.

CONCLUSION

HOPE after cold storage of fatty livers prevents significant reperfusion injury and improves graft function, comparable to the effects of HOPE in DCD livers and DCD kidneys. HOPE treatment is easy and may become a universal concept to further expand the donor pool.

LAY SUMMARY

An increasing number of donor livers contain fat. It is important to harness marginal livers, which may contain fat, as the stock of donor livers is limited. Hypothermic oxygenated perfusion (HOPE) prevents reperfusion injury and improves liver graft function. HOPE offers a simple and low-cost option for treating liver grafts in transplant centers, even after cold storage, instead of transporting machines to the place of procurement. HOPE could be used globally to expand the donor pool.

Enhanced recovery program versus traditional care after hepatectomy: A meta-analysis

To assess the safety and efficacy of enhanced recovery after surgery (ERAS) as compared with the traditional care in patients undergoing liver surgery and optimization of enhanced recovery programs.Literature, until August 2016, was searched to identify the comparative studies evaluating preoperative hospital stay time, complications, and C-reactive protein (CRP). Pooled odds ratios (OR) or weighted mean differences (WMDs) were calculated with either the fixed or random effect model.These studies included a total of 524 patients: 254 treated with ERAS and 270 with traditional care. The postoperative recovery time and length of hospital stay were significantly better than the control group (WMD -2.72; 95% confidence interval [CI] -3.86 to -1.57; WMD -2.67; 95% CI -3.68 to -1.65, respectively). The overall complications, grade I, and Grand II-V complications were significantly favorable to the ERAS group (OR, 0.45 [95% CI, 0.30-0.67]; OR, 0.55 [95% CI, 0.31-0.98]; OR, 0.49 [95% CI, 0.32-0.76], respectively). The concentration of CRP in the control group was significantly higher than that in the ERAS group on postoperative day 5 (WMD -21.68; 95% CI -29.30 to -14.05). Time to first flatus (WMD -0.93; 95% CI -1.41 to -0.46) was significantly shortened in the ERAS group.The evidence indicates that ERAS following liver surgery is safe, effective, and feasible. Therefore, further are essential for optimizing the ERAS protocols.

Omega-3 fatty acids inhibit oxidative stress in a rat model of liver regeneration

Purpose

Lipid peroxidation and consequent reactive oxygen species in the setting of oxidative stress have crucial roles in liver regeneration, which may adversely affect the regeneration itself and lead to liver failure. The aim of the current study is to investigate whether omega-3 fatty acid supplementation inhibits oxidative stress in an experimental model of liver regeneration.

Methods

Forty rats were allocated to four groups. Rats in group A received a sham operation. Rats in group B were subjected to right portal vein ligation (RPVL) and saline infusion. Rats in groups C and D were subjected to RPVL and total parenteral nutrition (TPN) with an all-in-one admixture containing a soybean oil based lipid emulsion. Rats in group D were additionally supplemented with omega-3 fatty acid infusion. Oxidative stresses in the blood and liver were measured by glutathione, superoxide dismutase, catalase, glutathione peroxidase, malondialdehyde, and nitric oxide.

Results

Omega-3 supplementation to the TPN solution significantly corrected alterations in the blood and tissue concentrations of oxidants and anti-oxidants during regeneration (P < 0.05).

Conclusion

Omega-3 fatty acid supplementation to the TPN solution revealed promising results in removal of oxidative stress that emerges during liver regeneration.

Effect of obeticholic acid on liver regeneration following portal vein embolization in an experimental model

Background

The bile salt-activated transcription factor farnesoid X receptor (FXR) is a key mediator of proliferative bile salt signalling, which is assumed to play a role in the early phase of compensatory liver growth. The aim of this study was to evaluate the effect of a potent FXR agonist (obeticholic acid, OCA) on liver growth following portal vein embolization (PVE).

Methods

Rabbits were allocated to receive daily oral gavage with OCA (10 mg/kg) or vehicle (control group) starting 7 days before PVE (n = 18 per group), and continued until 7 days after PVE. PVE of the cranial liver lobes was performed using polyvinyl alcohol particles and coils on day 0. Caudal liver volume (CLV) was analysed by CT volumetry on days –7, –1, +3 and +7. Liver function was determined by measuring mebrofenin uptake using hepatobiliary scintigraphy. Additional parameters analysed were plasma aminotransferase levels, and histological scoring of haematoxylin and eosin- and Ki-67-stained liver sections.

Results

Three days after PVE of the cranial lobes, the increase in CLV was 2·2-fold greater in the OCA group than in controls (mean(s.d.) 56·1(20·3) versus 26·1(15·4) per cent respectively; P &lt; 0·001). This increase remained greater 7 days after PVE (+1·5-fold; P = 0·020). The increase in caudal liver function at day +3 was greater in OCA-treated animals (+1·2-fold; P = 0·017). The number of Ki-67-positive hepatocytes was 1·6-fold higher in OCA-treated animals 3 days after PVE (P = 0·045). Plasma aminotransferase levels and histology did not differ significantly between groups.

Conclusion

OCA accelerated liver regeneration after PVE in a rabbit model. OCA treatment might increase the efficacy of PVE and, thereby, resectability.

Hepatic parenchymal transection increases liver volume but not function after portal vein embolization in rabbits

BACKGROUND

Associating liver partition with portal vein ligation for staged hepatectomy induces more extensive liver hypertrophy than ligation alone; however, the mechanisms underlying the accelerated liver regrowth and the functional quality of the hypertrophic liver are presently elusive. This study, therefore, investigated the effect of parenchymal transection on liver volume and function after portal vein embolization in a standardized rabbit model.

METHODS

Twelve rabbits were subjected to portal vein embolization of the cranial liver lobes and randomized between parenchymal transection of the left lateral liver lobe versus no transection (portal vein embolization only). Liver volume of the nonembolized liver lobe was assessed using computed tomography-volumetry, and liver uptake function was determined by ^99mTc-mebrofenin hepatobiliary scintigraphy before and 3 and 7 days after portal vein embolization.

RESULTS

The increase in nonembolized liver volume 3 days after portal vein embolization was 2.7-fold greater in the transected group compared with the portal vein embolization only group (56 ± 16% vs 21 ± 12%, respectively, P < .01) and 1.7-fold greater 7 days after portal vein embolization (113 ± 34% vs 68 ± 24%, P < .01). Liver uptake function did not differ between groups before portal vein embolization (8.4 ± 3.7%/min in the transection group vs 8.9 ± 1.6%/min) on day 3 (33.2 ± 4.7% after transection vs 30.3 ± 4.6%/min, respectively) and day 7 after portal vein embolization (42.6 ± 8.4% vs 39.1 ± 5.3%/min, respectively).

CONCLUSION

Parenchymal transection after portal vein embolization increases liver growth in terms of volume but not function. These results indicate that the rapid volume increase observed after associating liver partition with portal vein ligation for staged hepatectomy does not coincide with the clinically more relevant functional increase. Quantitative liver function tests might be essential in associating liver partition with portal vein ligation for staged hepatectomy to better assess the hypertrophy response and improve clinical decision-making.

Effectiveness of ω-3 Polyunsaturated Fatty Acids Based Lipid Emulsions for Treatment of Patients after Hepatectomy: A Prospective Clinical Trial

Objective: The present study aimed to investigate the effectiveness of parenteral nutritional support with ω-3 PUFAs–based lipid emulsions in patients after liver resection. Methods: A total of 119 patients were randomly assigned to the immunonutrition (IM) group (n = 59) and control group (n = 60). The IM group was continuously given Omegaven^® 10% 100 mL/day rather than regular nutrition for five days postoperatively. Venous blood samples were obtained from all subjects before surgery and D1, D3 and D7 after surgery. Results: No significant difference was found in baseline characteristics of the two groups. On D1 after surgery, no statistically significant differences were observed in the blood sample tests between the two groups. On D3 after surgery, the levels of white blood cell count (WBC), alanine aminotransferase (ALT), aspartate transaminase (AST) and total bilirubin (TBil) were dramatically decreased in the IM group (t = 3.065, p = 0.003; t = 2.149, p = 0.034; t = 5.313, p= 0.001; and t = 2.419, p = 0.017, respectively). Furthermore, on D7 after surgery, not only could a significant decrease be observed in the IM group concerning the levels of WBC, ALT and TBil (t = 3.025, p = 0.003; t = 2.094, p = 0.038; and t = 2.046, p = 0.043, respectively), but it was also seen in the level of Δprothrombintime (PT) (t = 2.450, p = 0.016). An increase in the level of prealbumin (Pre-Alb) in the IM group was observed on D7 after surgery (t = 2.237, p = 0.027). The frequency of total complications in the IM group were significantly lower than in the control group (χ² = 4.225, p = 0.040 and χ² = 3.174, p = 0.075). The trend favored the IM group in reducing the total infective complications rate (χ² = 3.174, p = 0.075). A significant decrease in the duration of the hospital stay after surgery was also observed in the IM group (t = 2.012, p = 0.047).Conclusion: ω-3 PUFAs–based lipid emulsions for treatment of patients after hepatectomy are safe and effective in controlling inflammation, protecting liver function, and consequently reducing the rate of total complications and the duration of the hospital stay.

Obesity and colorectal liver metastases: Mechanisms and management

INTRODUCTION

Colorectal cancer (CRC) is the third commonest malignancy after lung and breast cancer. The most common cause of mortality from CRC is from distant metastases. Obesity is a known risk factor for primary CRC development. However, its role in metastatic disease progression is not fully understood. The article aims to provide an overview of the role of obesity in colorectal liver metastases (CRLM). Furthermore, possible strategies to minimise this effect are discussed. An electronic search of MedLine, EMBASE, CINAHL and google scholar was performed. Relevant articles were included in the article. Obesity causes localised inflammation within the liver microenvironment which may predispose to metastases development. Furthermore, obesity causes systemic inflammation leading to release of protumourigenic growth factors. Several studies demonstrated the effects of lifestyle modification, medications, bariatric surgery and omega-3 fatty acids on steatosis within the context of liver surgery. It is currently unclear whether obesity directly leads to metastatic disease via chronic systemic inflammation or whether obesity induced steatosis provides a fertile microenvironment for metastases deposition. With a global increase in obesity useful strategies to minimise the effects of obesity on the liver include life-style modification, pre-operative dietary regimes and omega-3 fatty acids intake. Pre-operative optimisation of the patient is a key concept. Further randomised control trials are needed to guide management strategies.

Preoperative selection of patients with colorectal cancer liver metastasis for hepatic resection

Surgical resection of colorectal liver metastases (CRLM) has a well-documented improvement in survival. To benefit from this intervention, proper selection of patients who would be adequate surgical candidates becomes vital. A combination of imaging techniques may be utilized in the detection of the lesions. The criteria for resection are continuously evolving; currently, the requirements that need be met to undergo resection of CRLM are: the anticipation of attaining a negative margin (R0 resection), whilst maintaining an adequate functioning future liver remnant. The timing of hepatectomy in regards to resection of the primary remains controversial; before, after, or simultaneously. This depends mainly on the tumor burden and symptoms from the primary tumor. The role of chemotherapy differs according to the resectability of the liver lesion(s); no evidence of improved survival was shown in patients with resectable disease who received preoperative chemotherapy. Presence of extrahepatic disease in itself is no longer considered a reason to preclude patients from resection of their CRLM, providing limited extra-hepatic disease, although this currently is an area of active investigations. In conclusion, we review the indications, the adequate selection of patients and perioperative factors to be considered for resection of colorectal liver metastasis.

Effect of omega-3 on hepatic regeneration in adult living donors undergoing hepatic resections for liver transplantation: A randomized controlled trial

BACKGROUND

Omega-3 polyunsaturated fatty acids (ω-3 PUFAs) have been shown to improve liver regeneration in experimental models. Aim was to evaluate the effects of ω-3 PUFAs on hepatic regeneration in adult living donors undergoing partial hepatectomy for liver transplantation (LDLT).

METHODS

Forty LDLT donors were categorized into 2 groups: received either intravenous ω-3 PUFA-enriched lipid emulsion 20% infusion 7 mL/kg once a day for 2 days before surgery and postoperative day (POD) 0 (S group) or glucose 5% (C group). Hepatic regeneration was assessed by volume of the liver after 1 month using computed tomography, and serial serum levels of hepatocyte growth factor were measured at POD 1, 3, and 5.

RESULTS

Liver volume after 1 month was significantly larger in the S group than the C group (1286.75 ± 122.781 cm(3) vs 1169.15 ± 128.3, respectively; P = .00). Both the regeneration index and the regeneration percentage were significantly higher in the S group than the C group (P = .02 and P = .00, respectively). Serum levels of hepatocyte growth factor were significantly higher in the S group on POD 1, 3, and 5 than the C group ([in pg/mL] 188.10 ± 74.25 vs 123.30 ± 13.56, P = .00; 127.55 ± 32.40 vs 109.25 ± 8.89, P = .02; and 109.45 ± 21.44 vs 96.70 ± 5.57, P = .01; respectively).

CONCLUSION

Omega-3 polyunsaturated fatty acids effectively promoted liver regeneration and functional recovery following portal hypertension in the setting of LDLT.

"A randomized, double-blind study of the effects of omega-3 fatty acids (Omegaven) on outcome after major liver resection"

Background

The body is dependent on the exogenous supply of omega-3 polyunsaturated fatty acids (n3-PUFA). These essential fatty acids are key players in regulating metabolic signaling but also exert anti-inflammatory and anti-carcinogenic properties. The liver is a major metabolic organ involved in fatty acid metabolism. Under experimental conditions, n3-PUFA exert beneficial effect on hepatic steatosis, regeneration and inflammatory insults such as ischemic injury after surgery. Some of these effects have also been observed in human subjects. However, it is unclear whether perioperative administration of n3-PUFA is sufficient to protect the liver from ischemic injury. Therefore, we designed a randomized controlled trial (RCT) assessing n3-PUFA (pre-) conditioning strategies in patients scheduled for liver surgery.

Methods/Design

The Omegaven™ trial is a multi-centric, double-blind, randomized, placebo- controlled trial applying two single doses of Omegaven™ or placebo on 258 patients undergoing major liver resection. Primary endpoints are morbidity and mortality one month after hospital discharge, defined by the Clavien- Dindo classification of surgical complications (Ann Surg 240(2):205–13, 2004) as well as the Comprehensive Complication Index (CCI) (Ann Surg 258(1):1–7, 2013). Secondary outcome variables include length of Intensive Care Unit (ICU) and hospital stay, postoperative liver function tests, fatty acid and eicosanoid concentration, inflammatory markers in serum and in liver tissue. An interim analysis is scheduled after the first 30 patients per randomization group.

Discussion

Long-term administration of n3-PUFA have a beneficial effect on metabolism and hepatic injury. Patients often require surgery without much delay, thus long-term n3-PUFA uptake is not possible. Also, lack of compliance may lead to incomplete n3-PUFA substitution. Hence, perioperative Omegaven™ may provide an easy and controllable way to ensure hepaative application of tic protection.

Trial registration

ClinicalTrial.gov: ID: NCT01884948, registered June 14, 2013; Institution Ethical Board Approval: KEK-ZH-Nr. 2010–0038; Swissmedic Notification: 2012DR3215.

Omega-3 Polyunsaturated Fatty Acids Intake to Regulate Helicobacter pylori-Associated Gastric Diseases as Nonantimicrobial Dietary Approach

Omega-3 polyunsaturated fatty acids (n-3 PUFAs), commonly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), have been acknowledged as essential long-chain fatty acids imposing either optimal health promotion or the rescuing from chronic inflammatory diseases such as atherosclerosis, fatty liver, and various inflammatory gastrointestinal diseases. Recent studies dealing with EPA and DHA have sparked highest interests because detailed molecular mechanisms had been documented with the identification of its receptor, G protein coupled receptor, and GPR120. In this review article, we have described clear evidences showing that n-3 PUFAs could reduce various Helicobacter pylori- (H. pylori-) associated gastric diseases and extended to play even cancer preventive outcomes including H. pylori-associated gastric cancer by influencing multiple targets, including proliferation, survival, angiogenesis, inflammation, and metastasis. Since our previous studies strongly concluded that nonantimicrobial dietary approach for reducing inflammation, for instance, application of phytoceuticals, probiotics, natural products including Korean red ginseng, and walnut plentiful of n-3 PUFAs, might be prerequisite step for preventing H. pylori-associated gastric cancer as well as facilitating the rejuvenation of precancerous atrophic gastritis, these beneficial lipids can restore or modify inflammation-associated lipid distortion and correction of altered lipid rafts to send right signaling to maintain healthy stomach even after chronic H. pylori infection.

A clinical perspective of the link between metabolic syndrome and hepatocellular carcinoma

Metabolic syndrome (MS), which is defined as a constellation of clinico-biological features closely related to insulin-resistance has reached epidemic levels in Western Europe and Northern America. Non-alcoholic fatty liver disease (NAFLD) represents the hepatic manifestation of MS. As its incidence parallels that of MS, NAFLD is currently becoming one of the most frequent chronic liver diseases in Western countries. On one hand, MS favors the development of hepatocellular carcinoma (HCC) either through NAFLD liver parenchymal alterations (steatosis; steatohepatitis; fibrosis), or in the absence of significant underlying liver parenchyma changes. In this setting, HCC are often diagnosed incidentally, tend to be larger than in patients developing HCC on cirrhosis and therefore frequently require major liver resections. On the other hand, MS patients are at increased risk of both liver-related postoperative complications and increased cardiorespiratory events leading to non-negligible mortality rates following liver surgery. These deleterious effects seem to be related to the existence of impaired liver function even in the absence of severe fibrosis but also higher cardiorespiratory sensitivity in a setting of MS/NAFLD. Hence, specific medical and surgical improvements in the perioperative management of these patients are required. These include complete preoperative cardiorespiratory work-up and the wide use of preoperative liver volume modulation. Finally, the long-term prognosis after curative surgery for MS-related HCC does not seem to be worse than for other HCC occurring on classical chronic liver diseases. This is probably related to less aggressive tumor behavior with lower micro vascular invasion and decreased rates of poorly differentiated lesions. In this setting, several medical therapies including metformin could be of value in the prevention of both occurrence and recurrence of HCC.

Rodent models and imaging techniques to study liver regeneration

The liver has the unique capability of regeneration from various injuries. Different animal models and in vitro methods are used for studying the processes and mechanisms of liver regeneration. Animal models were established either by administration of hepatotoxic chemicals or by surgical approach. The administration of hepatotoxic chemicals results in the death of liver cells and in subsequent hepatic regeneration and tissue repair. Surgery includes partial hepatectomy and portal vein occlusion or diversion: hepatectomy leads to compensatory regeneration of the remnant liver lobe, whereas portal vein occlusion leads to atrophy of the ipsilateral lobe and to compensatory regeneration of the contralateral lobe. Adaptation of modern radiological imaging technologies to the small size of rodents made the visualization of rodent intrahepatic vascular anatomy possible. Advanced knowledge of the detailed intrahepatic 3D anatomy enabled the establishment of refined surgical techniques. The same technology allows the visualization of hepatic vascular regeneration. The development of modern histological image analysis tools improved the quantitative assessment of hepatic regeneration. Novel image analysis tools enable us to quantify reliably and reproducibly the proliferative rate of hepatocytes using whole-slide scans, thus reducing the sampling error. In this review, the refined rodent models and the newly developed imaging technology to study liver regeneration are summarized. This summary helps to integrate the current knowledge of liver regeneration and promises an enormous increase in hepatological knowledge in the near future.

Metabolic syndrome and non-alcoholic fatty liver disease in liver surgery: The new scourges?

The aim of this topic highlight is to review relevant evidence regarding the influence of the metabolic syndrome (MS) and its associated liver manifestation, non-alcoholic fatty liver disease (NAFLD), on the development of liver cancer as well as their impact on the results of major liver surgery. MS and NAFLD, whose incidences are significantly increasing in Western countries, are leading to a changing profile of the patients undergoing liver surgery. A MEDLINE search was performed for relevant articles using the key words "metabolic syndrome", "liver resection", "liver transplantation", "non alcoholic fatty liver disease", "non-alcoholic steatohepatitis" and "liver cancer". On one hand, the MS favors the development of primary liver malignancies (hepatocellular carcinoma and cholangiocarcinoma) either through NAFLD liver parenchymal alterations (steatosis, steatohepatitis, fibrosis) or in the absence of significant underlying liver parenchyma changes. Also, the existence of NAFLD may have a specific impact on colorectal liver metastases recurrence. On the other hand, the postoperative period following partial liver resection and liver transplantation is at increased risk of both postoperative complications and mortality. These deleterious effects seem to be related to the existence of liver specific complications but also higher cardio-vascular sensitivity in a setting of MS/NAFLD. Finally, the long-term prognosis after curative surgery joins that of patients operated on with other types of underlying liver diseases. An increased rate of patients with MS/NAFLD referred to hepatobiliary units has to be expected. The higher operative risk observed in this subset of patients will require specific improvements in their perioperative management.