COVID-19 and hepatic injury: cellular and molecular mechanisms in diverse liver cells

The coronavirus disease 2019(COVID-19)represents a global health and economic challenge.Hepatic injuries have been approved to be associated with severe acute respiratory syndrome coronavirus(SARS-CoV-2)infection.The viral tropism pattern of SARS-CoV-2 can induce hepatic injuries either by itself or by worsening the conditions of patients with hepatic diseases.Besides,other factors have been reported to play a crucial role in the pathological forms of hepatic injuries induced by SARS-CoV-2,including cytokine storm,hypoxia,endothelial cells,and even some treatments for COVID-19.On the other hand,several groups of people could be at risk of hepatic COVID-19 complications,such as pregnant women and neonates.The present review outlines and discusses the interplay between SARS-CoV-2 infection and hepatic injury,hepatic illness comorbidity,and risk factors.Besides,it is focused on the vaccination process and the role of developed vac-cines in preventing hepatic injuries due to SARS-CoV-2 infection.

Ex vivo-expanded bone marrow stem cells home to the liver and ameliorate functional recovery in a mouse model of acute hepatic injury

BACKGROUND:Stem cell transplantation provides a theoretical approach for liver regeneration medicine;it may promote liver regeneration and self-repair.However,the transplantation of bone marrow-mesenchymal stem cells expanded ex vivo as a therapy for liver disease has rarely been investigated.This study aimed to explore whether bone marrow stem cells expanded ex vivo home to the liver and foster hepatic recovery after CCl 4 injury.METHODS:Bone marrow cells from BALB/c mice were expanded ex vivo by multiple-passage cultivation,characterized by cytoflow immunofluorescence,and pre-labeled with PKH26 before intravenous infusion into animals treated with CCl 4.The integration of bone marrow cells into the liver was examined microscopically,and plasma hepatic enzymes were determined biochemically.RESULTS:Cultured bone marrow cells exhibited antigenic profiles comparable to those of primary medullary stem cells.Double immunofluorescence showed colocalization of these cells with proliferative activity and albumin expression in the liver of CCl 4 -treated mice.Densitometry showed increased in situ cell proliferation (50±14 vs 20±3 cells/high-power field,P<0.05) and albumin expression (149±25 vs 20±5 cells/high-power field,P<0.05) in the liver,as well as reduced serum aminotransferase levels (P<0.05) and better survival rates (P<0.05) in animals receiving cultured bone marrow cells relative to controls.CONCLUSIONS:Ex vivo-expanded bone marrow cells are capable of relocating to and proliferating in the chemically- injured liver.Transplantation of these pluripotent stem cells appears to improve serum indices of liver function and survival rate in mice after CCl4-induced hepatic damage.

Dimethylacetamide-induced Hepatic Injury in Vitro: Mechanism and Potential Preventive Strategy

N,N-Dimethylacetamide （DMAc） is a widely used organic solvent in modern chemical industry with low to moderate hepatotoxicity to occupational health of employees. But so far, there are fewer and less conclusive data concerning its pathogenic mechanism in detail. In current study, the toxicity of DMAc was firstly investigated on human normal hepatocytes （LO-2）, using a series of molecular biology measurements to ananlyze the effect and mechanism of DMAc-induced hepatic cell injury and explore effective prophylactic measures. We found that DMAc triggered LO-2 apoptosis in a obviously dose-dependent manner, caused by increased ROS generation and activation of Bcl-2 pathway. Significantly, glutathione （GSH） rather than vitamin C （Vit C） could partially inhibit DMAc-induced apoptosis thus showing potential as a effective precaution for workers.

Kupffer cells contribute to concanavalin A-induced hepatic injury through a Th1 but not Th17 type response-dependent pathway in mice

BACKGROUND:Increasing evidence suggests that a close interaction of Kupffer cells with T cells plays a central role in concanavalin A-induced hepatic injury in mice,but the underlying mechanisms remain obscure.The present study aimed to determine the relative roles of Th1 and Th17 type responses in concanavalin A-induced hepatic injury in mice, and to investigate whether or not Kupffer cells contribute to hepatic injury via a Th1 or Th17 type response-dependent pathway. METHODS:Immune-mediated hepatic injury was induced in C57BL/6 mice by intravenous injection of concanavalin A. Kupffer cells were inactivated by pretreatment with gadolinium chloride 24 hours before the concanavalin A injection.The interferon-gamma(IFN-γ)and interleukin-17(IL-17)pathways were blocked by specific neutralizing antibodies.Hepatic injury was assessed using serum transferase activity and pathological analysis.Expression of inflammatory cytokines within the liver was detected by real-time polymerase chain reaction and immunohistochemistry. RESULTS:Neutralization of IFN-γsignificantly attenuated concanavalin A-induced hepatic injury.However,neutralization of IL-17 failed to suppress the injury.Inactivation of Kupffer cells by gadolinium chloride pretreatment protected against concanavalin A-induced injury and significantly reduced hepatic cytokine levels including TNF-α,IL-6 and IFN-γbut not IL-17.CONCLUSION:Our findings suggest that Kupffer cells contribute to concanavalin A-induced hepatic injury via a Th1 type response-dependent pathway and production of inflammatory cytokines including TNF-α,IL-6 and IFN-γ.

Research status of the mechanism and treatment for acute pancreatitis complicated with hepatic injury

Acute pancreatitis（AP） is characterized by its sudden onset and rapid progression and is often complicated by liver injury. APinduced liver injury may develop into hepatic failure and even result in death. Thus, it is of importance to protect liver function and block injury-related pathways. In the pathogenesis of liver injury in AP, inflammatory cytokines, nuclear factor-kappa B（NF- κB） and oxygen free radicals play important roles. The complexity of the mechanism underlying the development of liver injury exerts, to some extent, a contribution to the difficulties in the treatment of this disease. Currently, the drugs used to treat the disease include L-arginine （L-Arg）, calcium ion antagonists, somatostatin and a variety of inflammatory mediator inhibitors. Additionally, some traditional Chinese medicines such as tfipterygium, wilfordii, rhubarb and salvia milfiorrhizae may also have some effects. In this article, the pathogenesis of liver injury in AP and its therapy are reviewed.

The new antioxidant 1-benzoyl-6-hydroxy-2,2,4-trimethyl-1,2- dihydroquinoline has a protective effect against carbon tetrachloride-induced hepatic injury in rats

Liver diseases with the central pathogenetic mechanism of oxidative stress are one of the main causes of mortality worldwide.Therefore,dihydroquinoline derivatives,which are precursors of hepatoprotectors and have antioxidant activity,are of interest.We have previously found that some compounds in this class have the ability to normalize redox homeostasis under experimental conditions.Here,we initially analyzed the hepatoprotective potential of the dihydroquinoline derivative 1-benzoyl-6-hydroxy-2,2,4-trimethyl-1,2-dihydroquinoline(BHDQ)for carbon tetrachloride(CCl4)-induced liver injury in rats.Results suggested that BHDQ normalized the alanine aminotransferase,aspartate aminotransferase,and gamma-glutamyl transpeptidase in serum.We also observed an improvement in liver tissue morphology related to BHDQ.Animals with CCl4-induced liver injuries treated with BHDQ had less oxidative stress compared to animals with CCl4-induced liver injury.BHDQ promoted activation changes in superoxide dismutase,catalase,glutathione peroxidase,glutathione reductase,and glutathione transferase on control values in animals with CCl4-induced liver injury.BHDQ also activated gene transcription in Sod1 and Gpx1 via nuclear factor erythroid 2-related factor 2 and forkhead box protein O1 factors.Therefore,the compound of concern has a hepatoprotective effect by inhibiting the development of necrotic processes in the liver tissue,through antioxidation.

Roles of Protein Kinase C and Fructose in Hepatic Injury Caused by Obstructive Jaundice

Summary： The regulating mechanism in hepatic injury caused by obstructive jaundice （OJ） was examined in this study. Rat hepatocytes were harvested by in situ collagenase perfusion and subjected to primary culture. The heptocytes were pre-treated with various concentrations of protein kinase C （PKC） agonist PMA and its inhibitor chelerythrine and cultured for 20 min. After the treatment, 50μmol/L glycochenodeoxycholate （GCDC） was added and the cells were cultured for an additional 24 h. Cells were then detected by flow cytometry （FCM） and TUNEL. After hepatocytes were treated with different concentrations of fructose and 100μM GCDC, the cells were examined by FCM and TUNEL. Experimental obstructive jaundice （BDL） was induced by double ligation of the bile duct. After BDL, the rats were fed with or without fructos and sacrificed 3, 7, 14 and 21 days after the ligation. The apoptotic status was observed in liver of all rats with TUNEL and PKC protein in liver of OJ was studied by immunohistochemical method. Our results showed that PMA increased GCDC-induced apoptosis and chelerythrine decreased GCSX-induced apoptosis in a concentration-dependent manner. After the treatment with fructose of different concentrations, 100μM GCDC decreased the apoptotic rate and the apoptotic rate decreased with the increase of fructose concentration. The apoptotic rate of liver was related to the time of OJ. Without the treatment of fructose, PKC and apoptosis index （AI） were highest 14 days after the bile duct ligation. With the treatment of fructose, apoptosis index （AI） and PKC were decreased from the 14th day after the bile duct ligation. It is concluded that PKC is involved in the regulation of apoptosis in the liver cells with OJ and plays important roles in the development and progression of liver injury caused by OJ. Fructose can protect hepatocytes in the bile salt-induced apoptosis by regulating PKC.

Polydatin ameliorates hepatic ischemia-reperfusion injury by modulating macrophage polarization

Background:Polydatin,a glucoside of resveratrol,has shown protective effects against various diseases.However,little is known about its effect on hepatic ischemia-reperfusion(I/R)injury.This study aimed to elucidate whether polydatin protects liver against I/R-induced injury and to explore the underlying mechanism.Methods:After gavage feeding polydatin once daily for a week,mice underwent a partial hepatic I/R procedure.Serum alanine aminotransferase(ALT)/aspartate aminotransferase(AST),hematoxylin-eosin(H&E)and TdT-mediated dUTP nick-end labeling(TUNEL)staining were used to evaluate liver injury.The severity related to the inflammatory response and reactive oxygen species(ROS)production was also investigated.Furthermore,immunofluorescence and Western blotting were used to detect macrophage polarization and the NF-κB signaling pathway in macrophages.Results:Compared with the I/R group,polydatin pretreatment significantly attenuated I/R-induced liver damage and apoptosis.The oxidative stress marker(dihydroethidium fluorescence,malondialdehyde,superoxide dismutase and glutathione peroxidase)and I/R related inflammatory cytokines(interleukin1β,interleukin-10 and tumor necrosis factor-α)were significantly suppressed after polydatin treatment.In addition,the result of immunofluorescence indicated that polydatin reduced the polarization of macrophages toward M1 macrophages both in vivo and in vitro.Western blotting showed that polydatin inhibited the pro-inflammatory function of RAW264.7 via down-regulating the NF-κB signaling pathway.Conclusions:Polydatin protects the liver from I/R injury by remodeling macrophage polarization via NFκB signaling.

Research progress of lncRNA and miRNA in hepatic ischemia-reperfusion injury

Background:Hepatic ischemia-reperfusion injury(HIRI)is a common complication of liver surgeries,such as hepatectomy and liver transplantation.In recent years,several non-coding RNAs(nc RNAs)including long non-coding RNAs(lnc RNAs)and micro RNAs(mi RNAs)have been identified as factors involved in the pathological progression of HIRI.In this review,we summarized the latest research on lnc RNAs,mi RNAs and the lnc RNA-mi RNA regulatory networks in HIRI.Data sources:The Pub Med and Web of Science databases were searched for articles published up to December 2021 using the following keywords:“hepatic ischemia-reperfusion injury”,“lnc RNA”,“long noncoding RNA”,“mi RNA”and“micro RNA”.The bibliography of the selected articles was manually screened to identify additional studies.Results:The mechanism of HIRI is complex,and involves multiple lnc RNAs and mi RNAs.The roles of lnc RNAs such as AK139328,CCAT1,MALAT1,TUG1 and NEAT1 have been established in HIRI.In addition,numerous mi RNAs are associated with apoptosis,autophagy,oxidative stress and cellular inflammation that accompany HIRI pathogenesis.Based on the literature,we conclude that four lnc RNA-mi RNA regulatory networks mediate the pathological progression of HIRI.Furthermore,the expression levels of some lnc RNAs and mi RNAs undergo significant changes during the progression of HIRI,and thus are potential prognostic markers and therapeutic targets.Conclusions:Complex lnc RNA-mi RNA-m RNA networks regulate HIRI progression through mutual activation and antagonism.It is necessary to screen for more HIRI-associated lnc RNAs and mi RNAs in order to identify novel therapeutic targets.

Non-coding RNAs:The potential biomarker or therapeutic target in hepatic ischemia-reperfusion injury

Hepatic ischemia-reperfusion injury(HIRI)is the major complication of liver surgery and liver transplantation,that may increase the postoperative morbidity,mortality,tumor progression,and metastasis.The underlying mechanisms have been extensively investigated in recent years.Among these,oxidative stress,inflammatory responses,immunoreactions,and cell death are the most studied.Non-coding RNAs(ncRNAs)are defined as the RNAs that do not encode proteins,but can regulate gene expressions.In recent years,ncRNAs have emerged as research hotspots for various diseases.During the progression of HIRI,ncRNAs are differentially expressed,while these dysregulations of ncRNAs,in turn,have been verified to be related to the above pathological processes involved in HIRI.ncRNAs mainly contain microRNAs,long ncRNAs,and circular RNAs,some of which have been reported as biomarkers for early diagnosis or assessment of liver damage severity,and as therapeutic targets to attenuate HIRI.Here,we briefly summarize the common pathophysiology of HIRI,describe the current knowledge of ncRNAs involved in HIRI in animal and human studies,and discuss the potential of ncRNA-targeted therapeutic strategies.Given the scarcity of clinical trials,there is still a long way to go from pre-clinical to clinical application,and further studies are needed to uncover their potential as therapeutic targets.

Protective effects of emodin and astragalus polysaccharides on chronic hepatic injury in rats

Background Chinese medicine plays an important role in hepatoprotective treatment. This study was conducted to investigate the protective effects of emodin and astragalus polysaccharides （APS） in a rat model of chronic hepatic injury. Methods Chronic hepatic injury was induced by hypodermic injection of an olive oil solution containing 40% carbon tetrachlodde （CCI4） twice a week, in addition to a diet of 79.5% maizena, 20% fat, 0.5% cholesterol, and 10% alcohol in the drinking water ad libitum for 12 weeks. Meanwhile, the rats were exposed to different concentrations of emodin （40 mg·kg^-1·d^-1）, APS （200 mg·kg^-1·d^-1）, combination drug （emodin 40 mg·kg^-1·d^-1 combined with APS 200 mg·kg^-1·d^-1） and colchicine （0.1 mg·kg^-1·d^-1） in parallel by oral gavage （once a day for 12 weeks）. At the end of 12 weeks, blood serum and liver tissue were taken. Serum was collected to determine the levels of total bilirubin （TBIL）, alanine transaminase （ALT）, aspartate transaminose （AST）, and albumin （ALB）. Liver and spleen indexes were assayed, followed by the measurements of the liver associated enzyme superoxide dismutase （SOD） and malondialdehyde （MDA）. Histopathological changes were studied using optical microscopy. Results Splenohepatomegalia was alleviated and serum levels of TBIL and ALT were reduced in the groups treated with emodin and APS when compared to the control group. In addition, the ALB level in the APS and combination groups was higher. Similarly, the SOD activity of liver homogenates was significantly higher in the groups treated with emodin and APS, while administration of the herbal derivatives prevented the elevation in MDA levels. Histological analysis showed that the APS and combination groups significantly ameliorated the hepatic injury. Conclusions Co-administration of emodin and APS demonstrated a synergistic action in reducing ALT and restoring ALB in the serum from a rat model of chronic hepatic injury. Emodin and APS may ameliorate the CCI4-induced hepatic injury in rats by elevating antioxidant-enzyme activities and reducing lipid peroxidation.

Comparative pharmacokinetics of bergenin,a main active constituent of Saxifraga stolonifera Curt.,in normal and hepatic injury rats after oral administration

Bergenin, isolated from the herb of Saxifrage stolonifera Curt.(Hu-Er-Cao) has hepatoprotective, anti-inflammatory, antitussive, and neuroprotective activities. The aim of the present study was to establish a simple, rapid, and sensitive RP-HPLC method for determination of bergenin in rat plasma and compare its oral pharmacokinetic behaviors in normal and CCl_4-induced hepatic injury rats. With norisoboldine as an internal standard, chromatographic separation was performed on a C_(18) analytical column with acetonitrile and water(11 : 89, V/V) containing 0.1% formic acid as the mobile phase. A good linearity was obtained over the range of 100^(–1)0 000 ng·m L^(–1). The lower limit of quantification was 50 ng·m L~(^(–1)). The developed method was successfully applied to a study of the pharmacokinetic difference of bergenin(100 mg·kg^(–1)) between normal and hepatic injury rats after oral administration. Marked alterations of pharmacokinetic parameters in hepatic injury rats were observed. Compared to normal rats, the AUC_((0–∞)) of bergenin in hepatic injury rats was elevated to 2.11-fold and C_(max) was increased by 130%, whereas CL value was only 55% of the normal rats, suggesting that the systemic exposure of bergenin was significantly increased under hepatic injury status.

Decreased serum albumin level indicates poor prognosis of COVID-19 patients: hepatic injury analysis from 2,623 hospitalized cases

Coronavirus disease 2019(COVID-19) is a global pandemic which has caused numerous deaths worldwide. The present study investigated the roles of hypoproteinemia in the clinical outcome and liver dysfunction of COVID-19 patients. In this retrospective study, we extracted data from 2,623 clinically confirmed adult COVID-19 patients(≥18 years old) between January 29,2020 and March 6, 2020 in Tongji Hospital, Wuhan, China. The patients were divided into three groups—non-critically ill,critically ill, and death groups—in accordance with the Chinese Clinical Guideline for COVID-19. Serum albumin, low-density lipoproteins cholesterol(LDL-C), and high-density lipoproteins cholesterol(HDL-C) concentrations and inflammatory cytokines levels were measured and compared among these three groups. The median age of these 2,623 patients was 64 years old(interquartile range(IQR), 52–71). Among the patients enrolled in the study, 2,008(76.6%) were diagnosed as non-critically ill and 615(23.4%) were critically ill patients, including 383(14.6%) critically ill survivors and 232(8.8%) critically ill deaths in the hospital. Marked hypoalbuminemia occurred in 38.2%, 71.2%, and 82.4% patients in non-critically ill, critically ill, and death groups, respectively, on admission and 45.9%, 77.7%, and 95.6% of these three groups, respectively, during hospitalization. We also discovered that serum low-density lipoprotein(LDL) and HDL levels were significantly lower in critically ill and death groups compared to non-critically ill group. Meanwhile, the patients displayed dramatically elevated levels of serum inflammatory factors, while a markedly prolonged activated partial thromboplastin time(APTT) in critically ill patients reflected coagulopathy. This study suggests that COVID-19-induced cytokine storm causes hepatotoxicity and subsequently critical hypoalbuminemia, which are associated with exacerbation of disease-associated inflammatory responses and progression of the disease and ultimately leads to death for some critically ill patients.

Changes of Pharmacokinetics of 6,7-Dimethoxycoumarin in A Rat Model of Alpha-Naphthylisothiocyanate-Induced Experimental Hepatic Injury after Yinchenhao Decoction(茵陈蒿汤) Treatment

Objective： To study the changes of pharmacokinetics of 6,7-dimethoxycoumarin in a rat model of alpha-naphthyiisothiocyanate （ANIT）-induced experimental hepatic injury after oral administration of Yinchenhao Decoction （茵陈蒿汤, YCHD） using an ultra pressure liquid chromatography （UPLC） method. Methods： Rats were divided into a normal group and a model group, after modeled by 4% ANIT （75 mg/kg） for 48 h, they were orally administrated with YCHD extract at the dose of 0.324 g/kg, and then blood was collected from their orbital sinus after different intervals. Changes in liver function were monitored by the levels of liver enzymes [alanine aminotransferase （ALl＇）, aspartate aminotransferase （AST）] and bilirubins [total bilirubin （TBIL）, direct bilirubin （DBIL）], the concentration of 6,7-dimethoxycoumarin in plasma were measured by UPLC, and the pharmaceutical parameters were calculated with DAS2.1.1 software. Results： The concentration-time curve of both normal and modeled rats after oral administration of YCHD was obtained. Their time to maximum plasma concentration （tmax were both 0.25 h, the maximum concentration （Cmax） were 4.533 iμ g/mL and 6.885 μg/mL, and their area under concentration-time curve （AUC）o→24h were 16.272 and 32.981, respectively. There was a 51.88% and 100.46% increase in Cmax and AUCo-t （P〈0.05）, but there showed a 45.52% and 92.93% reduction in clearance of drug and volum of distribution （P〈0.05）, respectively. Conclusions： Hepatic injury could significantly influence the pharmacokinetics of 6,7-dimethoxycoumarin after oral administration of YCHD, the absorption and distribution process was accelerated in liver injured rats, but the metabolism and elimination process was slowed. And this may lead to a significant accumulation of 6,7-dimethoxycoumarin in the body.

Effects of cefodizime on chemokines of liver tissues in mice with immunological hepatic injury

Background Chronic hepatic inflammation is characterized by the accumulation of lymphocytes as a consequence of increased recruitment from the blood and retention within the tissue at sites of infection. CXC chemokine ligand 16 （CXCL16） mRNA has been detected in both inflamed and normal liver tissues and is strongly upregulated in the injured liver tissues in a murine model. The aim of this study was to investigate the effect of cefodizime on CXCL16 mRNA of liver tissues in mice with immunological hepatic injury.Methods The murine model of immunological hepatic injury was induced by Bacillus Calmette Guerin and Lipoposaccharide. The mice with immunological hepatic injury were randomly assigned to the model group, the cefodizime group and the ceftriaxone group. The three groups were continuously given agents for seven days and CXCL16 mRNA of liver tissue was determined and contrasted with the control group treated by normal saline. Reverse transcription-polymerase chain reaction was used to assay CXCL16 mRNA levels in liver tissues.Results The expressions of CXCL16 mRNA were significantly higher in the model group and the ceftriaxone group than in the control group and the cefodizime group （P〈0.05）, indicating the mice in the model group and the ceftriaxone group were immunodeficient. There was no statistical difference in the expressions of CXCL16 mRNA between the control group and the cefodizime group. Similarly, no statistical difference in the expressions of CXCL16 mRNA between the model group and the ceftriaxone group was detected （P 〉0.05）. Conclusion Cefodizime effectively reduces the infiltration of lymphocytes into liver tissues and alleviates the liver damage by decreasing CXCL16 rnRNA in liver tissues in mice with immunological hepatic injury.

Characteristics and Outcome of Exertional Heatstroke Patients Complicated by Acute Hepatic Injury:A Cohort Study

Background and Aims:Exertional heatstroke(EHS)is associated with strenuous physical activity in hot environments.The present study aimed to investigate dynamic changes of hepatic function indices in EHS patients and determine risk factors for death.Methods:This single-center retrospective cohort study considered all patients with EHS admitted to the intensive care unit at the General Hospital of Southern Theater Command of PLA from October 2008 to May 2019.Data on general characteristics,organ function parameters,and the 90-day outcome of enrolled patients were collected.Hepatic indices were collected dynamically,and patients with acute hepatic injury(AHI)were identified by plasma total bilirubin(TBIL)≥34.2μmol/L and an international normalized ratio≥1.5,or with any grade of hepatic encephalopathy.Results:In patients who survived,TBIL,alanine aminotransferase and aspartate aminotransferase were increased at 24 h,peaked at 2–3 days,and began to decrease at 5 days.In non-survivors,TBIL continuously increased post-admission.The area under the receiver operating characteristic curve for the prediction of mortality based on sequential organ failure assessment(SOFA)scores was 89.8%,and the optimal cutoff value was 7.5.Myocardial injury and infection were identified as independent risk factors for death in EHS patients with AHI.Conclusions:In EHS patients,hepatic dysfunction usually occurred within 24 h.Patients with AHI had more severe clinical conditions,and significantly increased 90-day mortality rates.SOFA scores over 7.5,complicated with myocardial injury or infection,were found to be risk factors for death in EHS patients with AHI.

Fisetin mitigates hepatic ischemia-reperfusion injury by regulating GSK3β/AMPK/NLRP3 inflammasome pathway

Background: Hepatic ischemia-reperfusion(I/R) injury(IRI) represents a crucial challenge in liver transplantation. Fisetin has anti-inflammatory, anti-aging and anti-oxidative properties. This study aimed to examine whether fisetin mitigates hepatic IRI and examine its underlying mechanisms. Methods: Sham or warm hepatic I/R operated mice were pretreated with fisetin(5, 10 or 20 mg/kg). Hepatic histological assessments, TUNEL assays and serum aminotransferase measurements were performed. An in vitro hypoxia/reoxygenation(H/R) model using RAW264.7 macrophages pretreated with fisetin(2.5, 5 or 10 μmol/L) was also used. Serum and cell supernatant concentrations of interleukin-1 β(IL-1 β), IL-18 and tumor necrosis factor-α(TNF-α) were determined by enzyme-linked immunosorbent assay(ELISA). Protein levels of p-GSK3 β, p-AMPK and NLR family pyrin domain-containing 3(NLRP3)-associated proteins were detected by Western blotting. Results: Compared with the I/R group, fisetin pretreatment reduced pathological liver damage, serum aminotransferase levels, serum concentrations of IL-1 β, IL-18 and TNF-α in the murine IRI model. Fisetin also reduced the expression of NLRP3 inflammasome-associated proteins(NLRP3, cleaved caspase-1, IL-1 β and IL-18) in I/R-operated liver. The experiments in vitro showed that fisetin decreased the release of IL-1 β, IL-18 and TNF-α, and reduced the expression of NLRP3 inflammasome-associated proteins in H/R-treated RAW264.7 cells. Moreover, fisetin increased the expressions of p-GSK3 β and p-AMPK in both models, indicating that its anti-inflammatory effects were dependent on GSK3 β/AMPK signaling. The antiinflammatory effects of fisetin were partially inhibited by the AMPK specific inhibitor compound C. Conclusions: Fisetin showed protective effects against hepatic IRI, countering inflammatory responses through mediating the GSK3 β/AMPK/NLRP3 inflammasome pathway.

Hypoxia inducible factor 1α promotes interleukin-1 receptor antagonist expression during hepatic ischemia-reperfusion injury

BACKGROUND Ischemia-reperfusion injury(IRI) is a major risk associated with liver surgery and transplantation,and its pathological mechanism is complex.Interleukin-1 receptor antagonist(IL-1ra) can protect the liver from IRI.However,the regulatory mechanism of IL-1ra expression is still unclear.AIM To identify the mechanism that could protect the liver in the early stage of IRI.METHODS To screen the key genes in hepatic IRI,we performed RNA sequencing and gene enrichment analysis on liver tissue from mice with hepatic IRI.Subsequently,we verified the expression and effect of IL-1ra in hepatic IRI.We also used promoter mutagenesis and chromatin immunoprecipitation assay to search for the transcriptional regulatory sites of hypoxia-inducible factor(HIF)-1α.Finally,to explore the protective mechanism of ischemic preconditioning(IP),we examined the expression of HIF-1α and IL-1ra after IP.RESULTS We identified IL-1ra as a key regulator in hepatic IRI.The expression of IL-1ra was significantly upregulated after hepatic IRI both in vivo and in vitro.Furthermore,we found that HIF-1αregulated Il-1ra transcription in response to hypoxia.Increased HIF-1α accumulation promoted IL-1ra expression,whereas inhibition of HIF-1α exhibited the opposite effect.We also confirmed a predominant role for hypoxia response element in the regulation of Il1ra transcription by HIF-1αactivation.Of note,we demonstrated that IP protects against hepatic IRI by inducing IL-1ra expression,which is mediated through HIF-1α.CONCLUSION We demonstrated that ischemia or hypoxia leads to increased expression of IL-1ra through HIF-1α.Importantly,IP protects the liver from IRI via the HIF-1α–IL-1ra pathway.

New progress in understanding roles of nitric oxide during hepatic ischemia-reperfusion injury

Hepatic ischemia-reperfusion injury(HIRI)is a major clinical cause of morbidity and mortality in liver surgery and transplantation.Many studies have found that nitric oxide(NO)plays an important role in the HIRI and its increase or decrease can affect the progression and outcome of HIRI.However,the role of NO in HIRI is controversial and complicated.NO derived by endothelial NO synthase(eNOS)shows a protective role in HIRI,while excessive NO derived by inducible NO synthase(iNOS)accelerates inflammation and increases oxidative stress,further aggravating HIRI.Nevertheless,the overexpression of eNOS may exacerbate HIRI and iNOS-derived NO in some cases reduces HIRI.Here we review the new progress in the understanding of the roles of NO during HIRI:(1)NO possesses different roles in HIRI by increasing NO bioavailability,down-regulating leukotriene C4 synthase,inhibiting the activation of the nuclear factorκB(NFκB)pathway,enhancing cell autophagy,and reducing inflammatory cytokines and reactive oxygen species(ROS).And NO has both protective and deleterious effects by regulating apoptotic factors;(2)eNOS promotes NO production and suppresses its own overexpression,exerting a hepatoprotective effect reversely.Its activation is regulated by the PI3K/Akt and KLF2/AMPK pathways;and(3)iNOS derived NO mainly has deteriorating effects on HIRI,while it may have a protective function under some conditions.Their expression should reach a balance to reduce the adverse side and make NO protective in the treatment of HIRI.Thus,it can be inferred that NO modulating drugs may be a new direction in the treatment of HIRI or may be used as an adjunct to mitigate HIRI for the purpose of protecting the liver.

Effects of Shenqi Fuzheng injection on oxidative stress after hepatic ischemia-reperfusion injury

Objective:In order to determine Shenqi Fuzheng injection’s clinical effects and explore the impact on the SOD、MDA and liver function of patients,who underwent Hepatic ischemiareperfusion injury during the surgical operation.Methods:Forty patients were collected who were treated in Oncology Surgery of Bayi Hospital from January 2019 to August 2019.These patients were divided into control group and therapy group(Shenqi Fuzheng Injection)randomly,with 20 cases in each group.In the control group,one was switched to RF treatment during operation,one was only partially blocked during operation,and the remaining 38 cases completed the study.These remained patients were all operated with Pringle maneuver,then were treated with anti-infection,liver protection,acid suppression,fluid replacement,intravenous nutrition support and other symptomatic treatment after surgery.In addition,for the patients in the therapy group,the treatment of Shenqi Fuzheng injection were added once a day,which lasted 5 days.During the perioperative period,we would record their general conditions,SOD and MDA levels;liver function(ALT、AST、LDH).These data were analyzed statistically by SPSS 21.0 statistical software.Results:There was no statistically significant difference in general indicators related to the perioperative period between the two groups of patients(P>0.05).There was no significant difference in SOD and MDA levels between the two groups(P>0.05).,but at 1d,3d,and 5d after operation,the SOD level in the observation group was significantly higher than that in the control group(both P<0.05)and The MDA level in the observation group was significantly lower than the control group.The differences were statistically significant(all P<0.05).There was no significant difference in ALT and AST levels between the two groups before and after surgery(P>0.05),while the LDH levels in the two groups were not statistically different before surgery,on the first day after surgery,and on the third day after surgery(P>0.05),while there were statistical differences on the fifth day after surgery(P<0.05).Conclusions:For the pathients who received hepatectomy with Pringle maneuver,using Shenqi Fuzheng injection could improve the activity of antioxidant enzymes in the body,reduce the production of lipid peroxides,inhibit the oxidative stress response in the process of HIRI,thus it played a role in protecting the liver and accelerated the recovery.