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Extracellular cold-inducible RNA-binding protein (CIRP) is a proinflammatory mediator that aggravates ischaemia-reperfusion injury (IRI). Normothermic machine perfusion (NMP) could effectively alleviate the IRI of the liver, but the underlying mechanism remains to be explored. We show that human DCD livers secreted a large amount of CIRP during static cold storage (CS), which is released into the circulation after reperfusion. The expression of CIRP was related to postoperative IL-6 levels and liver function. In a rat model, the CIRP expression was upregulated during warm ischaemia and cold storage. Then, rat DCD livers were preserved using CS, hypothermic oxygenated machine perfusion (HOPE) and NMP. C23, a CIRP inhibitor, was administrated in the HOPE group. Compared with CS, NMP significantly inhibited CIRP expression and decreased oxidative stress by downregulating NADPH oxidase and upregulating UCP2. NMP markedly inhibited the mitochondrial fission-related proteins Drp-1 and Fis-1. Further, NMP increased the mitochondrial biogenesis-related protein, TFAM. NMP significantly reduced inflammatory reactions and apoptosis after reperfusion, and NMP-preserved liver tissue had higher bile secretion and ICG metabolism compared to the CS group. Moreover, C23 administration attenuated IRI in the HOPE group. Additionally, HL-7702 cells were stimulated with rhCIRP and C23. High rhCIRP levels increased oxidative stress and apoptosis. In summary, NMP attenuates the IRI of DCD liver by inhibiting CIRP-mediated oxidative stress and mitochondrial fission., (© 2021 The Authors. Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd.)

An aged liver has decreased reparative capacity during ischemia-reperfusion (IR) injury. A recent study showed that plasma irisin levels predict telomere length in healthy adults. The aim of the present study is to clarify the role of irisin, telomerase activity, and autophagy during hepatic IR in the elderly. To study this, hepatic IR was established in 22-month- and 3-month-old rats and primary hepatocytes were isolated. The results showed that the old rats exhibited more serious liver injury and lower levels of irisin expression, telomerase activity, autophagy ability, and mitochondrial function than young rats during hepatic IR. Irisin activated autophagy and improved mitochondrial function via increasing telomerase activity in aged hepatocytes. Inhibition of telomerase activity by BIBP1532 abolished the protective role of irisin in hepatocytes during hypoxia and reoxygenation. Additionally, this study proved irisin increased the telomerase activity via inhibition of the phosphorylation of JNK during hepatic IR. Administration of exogenous irisin significantly mitigated the inflammation, oxidative stress, apoptosis, and liver injury in an old rat model of hepatic IR. In conclusion, irisin improves autophagy of aged hepatocytes via increasing telomerase activity in hepatic IR. Irisin exhibits conspicuous benefits in increasing reparative capacity of an aged liver during hepatic IR., Competing Interests: The authors declare no competing financial interests., (Copyright © 2020 Jianbin Bi et al.)

Liver transplantation (LTx) is currently the most powerful treatment for end-stage liver disease. Although liver allograft is more tolerogenic compared to other solid organs, the majority of LTx recipients still require long-term immune suppression (IS) to control the undesired alloimmune responses, which can lead to severe side effects. Thus, understanding the mechanism of liver transplant tolerance and crosstalk between immune cells, especially alloreactive T cells and liver cells, can shed light on more specific tolerance induction strategies for future clinical translation. In this review, we focus on alloreactive T cell mediated immune responses and their crosstalk with liver sinusoidal endothelial cells (LSECs), hepatocytes, hepatic stellate cells (HSCs), and cholangiocytes in transplant setting. Liver cells mainly serve as antigen presenting cells (APCs) to T cells, but with low expression of co-stimulatory molecules. Crosstalk between them largely depends on the different expression of adhesion molecules and chemokine receptors. Inflammatory cytokines secreted by immune cells further elaborate this crosstalk and regulate the fate of naïve T cells differentiation within the liver graft. On the other hand, regulatory T cells (Tregs) play an essential role in inducing and keeping immune tolerance in LTx. Tregs based adoptive cell therapy provides an excellent therapeutic option for clinical transplant tolerance induction. However, many questions regarding cell therapy still need to be solved. Here we also address the current clinical trials of adoptive Tregs therapy and other tolerance induction strategies in LTx, together with future challenges for clinical translation from bench to bedside., (Copyright © 2019 Lei, Reinke, Volk, Lv and Wu.)

Objective: To introduce a novel laparoscopic training system with a continuously perfused ex-vivo porcine liver for hepatobiliary surgery., Background: Existing models for laparoscopic training, such as box trainers and virtual reality simulators, often fail to provide holistic training and real haptic feedback. We have formulated a new training system that addresses these problems., Methods: Real-Liver Laptrainer consists of a porcine liver, customized mannequin, ex-vivo machine perfusion system, and monitoring software. We made a detailed comparison of Real-Liver Laptrainer with the LapSim virtual reality simulator and the FLS Trainer Box systems. Five laparoscopic surgeons assessed the new system on multiple features. We assessed the performances of 43 trainees who used the new system to perform laparoscopic cholecystectomy (LC) three times., Results: Real-Liver Laptrainer offered more functions and better tactile feedback than the FLS or LapSim system. All five surgeons graded the quality of the new system as realistic. The utility of the system for training was scored as 3.6 ± 1.1 on a scale of 1-5. Between the first and third attempts, the number of successfully performed LCs increased (9 vs 14 vs 23; P = .011), while the numbers of liver damage incidents (25 vs. 21 vs. 18, P = .303) and gallbladder perforations decreased (17 vs. 12 vs. 9, P = .163). The mean LC operation time significantly decreased (63 vs. 50 vs. 44, P < .0001)., Conclusion: Real-Liver Laptrainer is a feasible, stable, and practical training model that has potential for improving the laparoscopic skills of surgeons.

Background: Hepatic ischemia-reperfusion (I/R) injury is a serious clinical complication that may compromise liver function because of extensive hepatocyte loss. Therefore, the development of novel and effective therapies for hepatic I/R is critical for the improvement of patient outcome. It has been previously shown that administration of milk fat globule-EGF factor VIII (MFG-E8), a membrane-associated secretory glycoprotein, exerts significant beneficial effects under acute inflammatory conditions through multiple physiological processes associated with tissue remodeling., Methods: To determine whether administration of recombinant human (rh) MFG-E8 attenuates liver injury in an animal model of hepatic I/R, male adult rats were subjected to 70% hepatic ischemia for 90 min, followed by reperfusion. At the beginning of reperfusion, rats were treated intravenously with normal saline (vehicle) or rhMFG-E8 (160 μg/kg) over a period of 30 min. MFG-E8 levels and various measurements were assessed 4 h after reperfusion. In addition, survival study was conducted in MFG-E8(-/-) and rhMFG-E8-treated wild-type (WT) mice using a total hepatic ischemia model., Results: Liver and plasma MFG-E8 protein levels were significantly decreased after hepatic I/R. Administration of rhMFG-E8 significantly improved liver injury, suppressed apoptosis, attenuated inflammation and oxidative stress, and downregulated NF-κB pathway. We also noticed that rhMFG-E8 treatment restored the downregulated PPAR-γ expression after hepatic I/R. MFG-E8(-/-) mice showed deterioration on survival and, in contrast, rhMFG-E8-treated WT mice showed a significant improvement of survival compared with vehicle-treated WT mice., Conclusions: MFG-E8-mediated multiple physiological events may represent an effective therapeutic option in tissue injury following an episode of hepatic I/R., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Background: The liver is a major organ that is susceptible to injury after blunt or penetrating trauma to the abdomen. No specific nonoperative treatment exists for traumatic hepatic injury (THI). Adrenomedullin (AM), a vasoactive peptide, combined with its binding protein, AM protein (AMBP-1), is beneficial in various disease conditions. In this study, we propose to analyze whether human AM combined with human AMBP-1 provides benefit in a model of THI in the rat., Methods: Male adult rats were subjected to trauma hemorrhage by resection of ∼50% of total liver tissues and allowed bleeding for 15 minutes. Immediately thereafter, human AM (48 μg/kg birth weight) plus human AMBP-1 (160 μg/kg birth weight) were given intravenously over 30 minutes in 1-mL normal saline. After 4 hours, the rats were killed, blood was collected, and tissue injury indicators were assessed. A 10-day survival study was also conducted., Results: At 4 hours after THI, plasma AMBP-1 levels were markedly decreased. Plasma levels of liver injury indicators (i.e., aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase) were significantly increased after THI. Similarly, lactate, creatinine, and tumor necrosis factor-α levels were significantly increased after THI. Administration of human AM/AMBP-1 after THI produced significant decreases of 64%, 23%, and 19% of plasma aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase levels, respectively. Similarly, plasma levels of lactate, creatinine, and tumor necrosis factor-α were also decreased by 42%, 28%, and 46% after human AM/AMBP-1 treatment, respectively. In a 10-day survival study, although vehicle treatment produced 41% survival, human AM/AMBP-1 treatment improved the survival rate to 81%., Conclusions: Administration of human AM/AMBP-1 significantly attenuated tissue injury and inflammation and improved survival after THI. Thus, human AM/AMBP-1 can be developed as a novel treatment for victims with uncontrolled traumatic hemorrhage.

Objective: To determine whether administration of a vasoactive peptide, human adrenomedullin (AM), in combination with its binding protein (ie, AMBP-1), prevents or minimizes hepatic ischemia-reperfusion (I/R) injury., Summary Background Data: Hepatic I/R injury results from tissue hypoxia and subsequent inflammatory responses. Even though numerous pharmacological modalities and substances have been studied to reduce I/R-induced mortality, none have been entirely successful. We have shown that administration of AM/AMBP-1 produces significant beneficial effects under various pathophysiological conditions. However, it remains unknown if human AM/AMBP-1 has any protective effects on hepatic I/R-induced tissue damage and mortality., Methods: Seventy percent hepatic ischemia was induced in male adult rats by placing a microvascular clip across the hilum of the left and median lobes for 90 minutes. After removing the clip, human AM alone, human AMBP-1 alone, human AM in combination with human AMBP-1 or vehicle was administered intravenously over a period of 30 minutes. Blood and tissue samples were collected 4 hours after reperfusion for various measurements. In additional groups of animals, the nonischemic liver lobes were resected at the end of 90-minute ischemia. The animals were monitored for 7 days and survival was recorded., Results: After hepatic I/R, plasma levels of AM were significantly increased, whereas AMBP-1 levels were markedly decreased. Likewise, gene expression of AM in the liver was increased significantly, whereas AMBP-1 expression was markedly decreased. Administration of AM in combination with AMBP-1 immediately after the onset of reperfusion down-regulated inflammatory cytokines, decreased hepatic neutrophil infiltration, inhibited liver cell apoptosis and necrosis, and reduced liver injury and mortality in a rat model of hepatic I/R. On the other hand, administration of human AM alone or human AMBP-1 alone after hepatic I/R failed to produce significant protection., Conclusions: Human AM/AMBP-1 may be a novel treatment to attenuate tissue injury after an episode of hepatic ischemia.

Background: Norepinephrine (NE) modulates the responsiveness of macrophages to proinflammatory stimuli through the activation of adrenergic receptors (ARs). Being part of the stress response, early increases of NE in sepsis sustain adverse systemic inflammatory responses. The intestine is an important source of NE release in the early stage of cecal ligation and puncture (CLP)-induced sepsis in rats, which then stimulates TNF-alpha production in Kupffer cells (KCs) through the activation of the alpha(2)-AR. It is important to know which of the three alpha(2)-AR subtypes (i.e., alpha(2A), alpha(2B) or alpha(2C)) is responsible for the upregulation of TNF-alpha production. The aim of this study was to determine the contribution of alpha(2A)-AR in this process., Methodology/principal Findings: Adult male rats underwent CLP and KCs were isolated 2 h later. Gene expression of alpha(2A)-AR was determined. In additional experiments, cultured KCs were incubated with NE with or without BRL-44408 maleate, a specific alpha(2A)-AR antagonist, and intraportal infusion of NE for 2 h with or without BRL-44408 maleate was carried out in normal animals. Finally, the impact of alpha(2A)-AR activation by NE was investigated under inflammatory conditions (i.e., endotoxemia and CLP). Gene expression of the alpha(2A)-AR subtype was significantly upregulated after CLP. NE increased the release of TNF-alpha in cultured KCs, which was specifically inhibited by the alpha(2A)-AR antagonist BRL-44408. Equally, intraportal NE infusion increased TNF-alpha gene expression in KCs and plasma TNF-alpha which was also abrogated by co-administration of BRL-44408. NE also potentiated LPS-induced TNF-alpha release via the alpha(2A)-AR in vitro and in vivo. This potentiation of TNF-alpha release by NE was mediated through the alpha(2A)-AR coupled Galphai protein and the activation of the p38 MAP kinase. Treatment of septic animals with BRL-44408 suppressed TNF-alpha, prevented multiple organ injury and significantly improved survival from 45% to 75%., Conclusions/significance: Our novel finding is that hyperresponsiveness to alpha(2)-AR stimulation observed in sepsis is primarily due to an increase in alpha(2A)-AR expression in KCs. This appears to be in part responsible for the increased proinflammatory response and ensuing organ injury in sepsis. These findings provide important feasibility information for further developing the alpha(2A)-AR antagonist as a new therapy for sepsis.

Objective: To study the gene expression of adhesion molecules in pulmonary and hepatic microvascular endothelial cells during sepsis in mice., Methods: Male mice were subjected to cecal ligation and puncture (CLP) and microvascular endothelial cells in pulmonary and hepatic tissues were harvested at 3 hours (early sepsis) and 12 hours (late sepsis) after CLP, respectively. Gene expression of the adhesion molecules was assessed by reverse transcription polymerase chain reaction (RT-PCR). Simultaneously, the alterations of myeloperoxidase (MPO) activity in pulmonary and hepatic tissues were also examined., Results: E-selectin mRNA levels markedly increased at 3 hours after CLP in both pulmonary and hepatic microvascular endothelial cells, then they returned to the normal level at 12 hours after CLP. Increases in intercellular adhesion molecule-1 (ICAM-1) mRNA levels were found at 3 hours after CLP in both pulmonary and hepatic microvascular endothelial cells, and these levels became higher at 12 hours after CLP. Adhesion molecule-1 (VCAM-1) mRNA expression of vascular cells also increased significantly at 3 hours and 12 hours after CLP in both pulmonary and hepatic microvascular endothelial cells. The level of VCAM-1 mRNA in hepatic microvascular endothelial cells was higher at 3 hours than that at 12 hours after CLP, while the level of VCAM-1 mRNA in pulmonary microvascular endothelial cells was higher at 12 hours than that at 3 hours after CLP. The MPO activity in pulmonary and hepatic tissues increased at 3 hours after CLP, compared with that of the sham group. They both declined significantly at 12 hours after CLP, but they were still higher than that of the sham group., Conclusions: The up-regulation of the gene expression of adhesion molecules in pulmonary and hepatic microvascular endothelial cells is an important step for the migration and accumulation of leukocytes at the site of inflammation, which plays a critical role in organ damage during sepsis. And the contribution of the heterogeneity of endothelial cells in organs' vulnerability during sepsis is worth a further investigation.

Background: Sepsis remains a major health issue without an effective therapy. Ferroptosis, an iron‐dependent programmed cell death, has been proposed to be related to the pathogenesis of sepsis. Irisin, a myokine released during exercise, improves mitochondrial function under various conditions. Ferroptosis is closely related to mitochondrial function. However, the role of irisin in sepsis‐induced ferroptosis and mitochondrial dysfunction in the liver remained unknown. Thus, we hypothesize that irisin treatment suppresses ferroptosis and improves mitochondrial function in sepsis. Methods: To study this, we first explored the role of serum irisin levels in patients with sepsis, and then determined the effect of irisin administration on ferroptosis and mitochondrial function in the liver of septic mice. Results: Serum irisin levels were decreased and negatively correlated with the APACHE II scores in patients with sepsis. In mice subjected to cecal ligation and puncture (CLP), exogenous irisin administration suppressed ferroptosis, inhibited inflammatory response, decreased reactive oxygen species (ROS) production, restored abnormal mitochondrial morphology, and increased mtDNA copy number and adenosine triphosphate (ATP) content. The effect of irisin on ferroptosis was confirmed in LPS‐treated hepatocytes and CLP‐induced septic mice. Inhibition of glutathione peroxidase 4 (GPX4), a central regulator of ferroptosis, reduced irisin's protective effects in LPS‐treated hepatocytes and CLP‐induced septic mice, while blocking the irisin receptor with RGD peptide or Echistain decreased irisin‐induced GPX4 expression. Conclusions: Serum irisin levels are decreased and negatively correlated with disease severity in patients with sepsis, and irisin treatment suppresses ferroptosis and restores mitochondrial function in experimental sepsis. Irisin may offer therapeutic potential in the management of sepsis. [ABSTRACT FROM AUTHOR]

Background: Despite advances in our understanding of excessive alcohol-intake-related tissue injury and modernization of the management of septic patients, high morbidity and mortality caused by infectious diseases in alcohol abusers remain a prominent challenge. Our previous studies have shown that milk fat globule epidermal growth factor-factor VIII (MFG-E8), a protein required to opsonize apoptotic cells for phagocytosis, is protective in inflammation. However, it remains unknown whether MFG-E8 ameliorates sepsis-induced apoptosis and organ injury in alcohol-intoxicated rats. The purpose of this study was to determine whether recombinant murine MFG-E8 (rmMFG-E8) attenuates organ injury after acute alcohol exposure and subsequent sepsis. Methods: Acute alcohol intoxication was induced in male adult rats by a bolus injection of intravenous alcohol at 1.75 g/kg BW, followed by an intravenous infusion of 300 mg/kg BW/h of alcohol for 10 hours. Sepsis was induced at the end of 10-hour alcohol infusion by cecal ligation and puncture (CLP). rmMFG-E8 or vehicle (normal saline) was administered intravenously 3 times (i.e., at the beginning of alcohol injection, the beginning of CLP, and 10 hours post-CLP) at a dose of 20 μg/kg BW each. Blood and tissue samples were collected 20 hours after CLP in alcoholic animals for various measurements. Results: Acute alcohol exposure per se did not affect the production of MFG-E8; however, it primed the animal and enhanced sepsis-induced MFG-E8 downregulation in the spleen. Administration of rmMFG-E8 reduces alcohol/sepsis-induced apoptosis in the spleen, lungs, and liver. In addition, administration of rmMFG-E8 after alcohol exposure and subsequent sepsis decreases circulating levels of TNF-α and interleukin-6 and attenuates organ injury. Conclusions: rmMFG-E8 attenuates sepsis-induced apoptosis and organ injury in alcohol-intoxicated rats. [ABSTRACT FROM AUTHOR]

Background: The “double-hit” model of hemorrhage and sepsis mimics the critically ill patient admitted to the surgical intensive care unit. Although the protein expression of a cytochrome (CYP) P-450 isoform CYP1A2 is reduced in the late stage of sepsis, the effect of hemorrhage on CYP isoforms and the anti-inflammatory nuclear receptor peroxisome proliferator-activated receptor-γ (PPAR-γ) has not been investigated. We hypothesized that hemorrhage down-regulates CYP isoforms and PPAR-γ in the liver, which plays an important role in producing tissue injury and proinflammatory responses after the subsequent sepsis (i.e., double-hit). Materials and methods: Male Sprague Dawley rats were divided into four groups. Animals in the double-hit group underwent hemorrhage (40 ± 2 mmHg for 90 min) followed by fluid resuscitation. Polymicrobial sepsis was induced by cecal ligation and puncture (CLP) 20 h after hemorrhage, and the animals were sacrificed 4 h after CLP. Rats in the hemorrhage-alone group were sacrificed 20 h after the insult. Rats in the CLP-alone group were sacrificed 4 h after the onset of sepsis. Animals in the sham-operated group underwent neither hemorrhage nor CLP. The gene expression of P-450 isoforms (i.e., CYP1A2 and 2C11) and PPAR-γ in the liver was determined using RT-PCR. Serum concentrations of alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate, and proinflammatory cytokines (i.e., IL-6, TNF-α) were also assessed. Results: In the hemorrhage-alone group, hepatic mRNA expression of CYP1A2, CYP2C11, and PPAR-γ was significantly down-regulated 20 h after the initial stress compared with sham-operated rats. Double-hit did not appear to further decrease CYP and PPAR-γ gene expression. In contrast, serum levels of AST, ALT, lactate, IL-6, and TNF-α did not change significantly in either hemorrhaged or septic animals. Those organ injury indicators and cytokines, however, were significantly elevated after the double-hit of hemorrhage and sepsis. Conclusions: Hepatic CYP1A2, CYP2C11, and PPAR-γ were down-regulated after the initial stress (hemorrhage). These down-regulated CYPs and PPAR-γ seem to work as important factors contributing to the progression of organ injury and proinflammatory responses after the second stress (CLP). [Copyright &y& Elsevier]

Sex affects the risk, treatment responses and outcome of many types of cancers. The mechanism of gender disparity in development of hepatocellular carcinoma (HCC) remains obscure. Sex-determining region on Y chromosome (SRY) was overexpressed in approximate 84% male patient HCC. Moreover, we are the first to generate a liver-specific transgenic (TG) murine model with overexpression of the male specific gene SRY. Subject to a single intraperitoneal injection N-nitrosodiethylamine (DEN) at day 14, TG and wildtype (WT) mice of both genders were sacrificed at different time points (6-13.5 months). Overexpression of SRY in male TG and ectopic expression of SRY in female TG livers promoted DEN-induced hepatocarcinogenesis compared to age- and sex-matched WT. This accelerated tumorigenesis in TG of both genders was a consequence of increased injury and inflammation, fibrosis, and compensatory enhancement in hepatocytes proliferation secondary to activation of downstream targets Sox9 and platelet-derived growth factor receptor α (PDGFRα)/phosphoinositide 3-kinase (PI3K)/Akt and c-myc/CyclinD1. In conclusion, activation of SRY and its downstream Sox9 and PDGFRα pathways are commonly involved in male hepatocarcinogenesis, which provides novel insights into gender disparity and sex-specific therapeutic strategies of HCC. [ABSTRACT FROM AUTHOR]