Management of sepsis in patients with liver failure. Curr Opin Crit Care. 2008;14:189-197. [PMID: 18388682 DOI: 10.1097/MCC.0b013e3282f6a435]

Immune checkpoint molecule Tim-3 promotes NKT cell apoptosis and predicts poorer prognosis in Sepsis

BACKGROUND

Sepsis is a leading cause of death among critically ill patients, which is defined as life-threatening organ dysfunction caused by a deregulated host immune response to infection. Immune checkpoint molecule Tim-3 plays important and complex roles in regulating immune responses and in inducing immune tolerance. Although immune checkpoint blockade would be expected as a promising therapeutic strategy for sepsis, but the underlying mechanism remain unknown, especially under clinical conditions.

METHODS

Tim-3 expression and apoptosis in NKT cells were compared in septic patients (27 patients with sepsis and 28 patients with septic shock). Phenotypic and functional characterization of Tim-3+ NKT cells were analysed, and then the relationship between Tim-3 + NKT cells and clinical prognosis were investigated in septic patients. α-lactose (Tim-3/Galectin-9 signalling inhibitor) and Tim-3 mutant mice (targeting mutation of the Tim-3 cytoplasmic domain) were utilized to evaluate the protective effect of Tim-3 signalling blockade following septic challenge.

RESULTS

There is a close correlation between Tim-3 expression and the functional status of NKT cells in septic patients, Upregulated Tim-3 expression promoted NKT cell activation and apoptosis during the early stage of sepsis, and it was associated with worse disease severity and poorer prognosis in septic patients. Blockade of the Tim-3/Galectin-9 signal axis using α-lactose inhibited in vitro apoptosis of NKT cells isolated from septic patients. Impaired activity of Tim-3 protected mice following septic challenge.

CONCLUSIONS

Overall, these findings demonstrated that immune checkpoint molecule Tim-3 in NKT cells plays a critical role in the immunopathogenesis of septic patients. Blockade of immune checkpoint molecule Tim-3 may be a promising immunomodulatory strategy in future clinical practice for the management of sepsis.

Roquin-1 resolves sepsis-associated acute liver injury by regulating inflammatory profiles via miRNA cargo in extracellular vesicles

Sepsis-associated acute liver injury (SALI) is an independent risk for sepsis-induced death orchestrated by innate and adaptive immune responses. Here, we found that Roquin-1 was decreased during SALI and expressed mainly in monocyte-derived macrophages. Meanwhile, Roquin-1 was correlated with the inflammatory profiles in humans and mice. Mechanically, Roquin-1 in macrophages promoted Ago2-K258-ubiquitination and inhibited Ago2-S387/S828-phosphorylation. Ago2-S387-phosphorylation inhibited Ago2-miRNA's complex location in multivesicular bodies and sorting in macrophages-derived extracellular vesicles (MDEVs), while Ago2-S828-phosphorylation modulated the binding between Ago2 and miRNAs by special miRNAs-motifs. Then, the anti-inflammatory miRNAs in MDEVs decreased TSC22D2 expression directly, upregulated Tregs-differentiation via TSC22D2-STAT3 signaling, and inhibited M1-macrophage-polarization by TSC22D2-AMPKα-mTOR pathway. Furthermore, WT MDEVs in mice alleviated SALI by increasing Tregs ratio and decreasing M1-macrophage frequency synchronously. Our study showed that Roquin-1 in macrophages increased Tregs-differentiation and decreased M1-macrophage-polarization simultaneously via miRNA in MDEVs, suggesting Roquin-1 can be used as a potential tool for SALI treatment and MDEVs engineering.

Myristica fragrans Extract Inhibits Platelet Desialylation and Activation to Ameliorate Sepsis-Associated Thrombocytopenia in a Murine CLP-Induced Sepsis Model

Sepsis, characterized by an uncontrolled host inflammatory response to infections, remains a leading cause of death in critically ill patients worldwide. Sepsis-associated thrombocytopenia (SAT), a common disease in patients with sepsis, is an indicator of disease severity. Therefore, alleviating SAT is an important aspect of sepsis treatment; however, platelet transfusion is the only available treatment strategy for SAT. The pathogenesis of SAT involves increased platelet desialylation and activation. In this study, we investigated the effects of Myristica fragrans ethanol extract (MF) on sepsis and SAT. Desialylation and activation of platelets treated with sialidase and adenosine diphosphate (platelet agonist) were assessed using flow cytometry. The extract inhibited platelet desialylation and activation via inhibiting bacterial sialidase activity in washed platelets. Moreover, MF improved survival and reduced organ damage and inflammation in a mouse model of cecal ligation and puncture (CLP)-induced sepsis. It also prevented platelet desialylation and activation via inhibiting circulating sialidase activity, while maintaining platelet count. Inhibition of platelet desialylation reduces hepatic Ashwell-Morell receptor-mediated platelet clearance, thereby reducing hepatic JAK2/STAT3 phosphorylation and thrombopoietin mRNA expression. This study lays a foundation for the development of plant-derived therapeutics for sepsis and SAT and provides insights into sialidase-inhibition-based sepsis treatment strategies.

Immune dysregulation and RNA N6-methyladenosine modification in sepsis

Sepsis is defined as life-threatening organ dysfunction caused by the host immune dysregulation to infection. It is a highly heterogeneous syndrome with complex pathophysiological mechanisms. The host immune response to sepsis can be divided into hyper-inflammatory and immune-suppressive phases which could exist simultaneously. In the initial stage, systemic immune response is activated after exposure to pathogens. Both innate and adaptive immune cells undergo epigenomic, transcriptomic, and functional reprogramming, resulting in systemic and persistent inflammatory responses. Following the hyper-inflammatory phase, the body is in a state of continuous immunosuppression, which is related to immune cell apoptosis, metabolic failure, and epigenetic reprogramming. Immunosuppression leads to increased susceptibility to secondary infections in patients with sepsis. RNA N6-Methyladenosine (m6A) has been recognized as an indispensable epitranscriptomic modification involved in both physiological and pathological processes. Recent studies suggest that m6A could reprogram both innate and adaptive immune cells through posttranscriptional regulation of RNA metabolism. Dysregulated m6A modifications contribute to the pathogenesis of immune-related diseases. In this review, we summarize immune cell changes and the potential role of m6A modification in sepsis. This article is categorized under: RNA in Disease and Development > RNA in Disease RNA Processing > RNA Editing and Modification.

Homeodomain-interacting protein kinase 2 regulates NLRP3 inflammasome activation through endoplasmic reticulum stress in septic liver injury

OBJECTIVE

Septic liver injury is a major burden for the clinical management of sepsis. Hepatocyte cell death plays a crucial pathophysiological role in sepsis. A recent study proposed that NLRP3 inflammasome-mediated pyroptosis participates in septic liver injury. Therefore, investigating the mechanism controlling this process may help manage sepsis.

METHODS

We investigated the role of homeodomain-interacting protein kinase 2 (HIPK2) in regulating the NLRP3 inflammasome in vivo using mouse models and in vitro in primary hepatocytes.

RESULTS

HIPK2 could improve liver injury and survival in a mouse model of sepsis. Overexpression of HIPK2 could suppress NLRP3 and caspase-1-p20 expression, while HIPK2 knockdown led to higher levels of these two molecules. Importantly, HIPK2 could suppress endoplasmic reticulum (ER) stress. Pharmacologically inhibiting ER stress could abolish activation of the NLRP3 inflammasome in hepatocytes with HIPK2 knockdown.

CONCLUSION

HIPK2 can regulate ER stress and NLRP3 inflammasome activation in the liver during sepsis, and HIPK2-mediated suppression of ER stress participates in regulating NLRP3 inflammasome activation. The present study highlights the role of HIPK2 in regulating the inflammasome in septic liver injury, which may serve as a target for managing sepsis.

Thymol regulates the Endothelin-1 at gene expression and protein synthesis levels in septic rats

Sepsis is a serious systemic inflammatory response to infections. In this study, effects of thymol treatments on sepsis response were investigated. A total of 24 rats were randomly divided into 3 different treatment groups, namely as Control, Sepsis and Thymol. A sepsis model was created with a cecal ligation and perforation (CLP) in the sepsis group. For the treatment group, 100 mg/kg dose of thymol was administered via oral gavage and sepsis was established with a CLP after 1 h. All rats were sacrificed at 12 h post-opia. Blood and tissue samples were taken. ALT, AST, urea, creatinine and LDH were evaluated to assess the sepsis response in separated sera. Gene expression analysis was conducted for ET-1, TNF-α, IL-1 in lung, kidney and liver tissue samples. ET-1 and thymol interactions were determined by molecular docking studies. The ET-1, SOD, GSH-Px and MDA levels were determined by ELISA method. Genetic, biochemical and histopathological results were evaluated statistically. The pro-inflammatory cytokines and ET-1 gene expression revealed a significant decrease in the treatment groups, while there was an increase in septic groups. SOD, GSH-Px and MDA levels of rat tissues were significantly different in the thymol groups as compared to the sepsis groups (p < 0.05). Likewise, ET-1 levels were significantly reduced in the thymol groups. In terms of serum parameters, present findings were consistent with the literature. It was concluded based on present findings that thymol therapy may reduce sepsis-related morbidity, which would be beneficial in the early phase of the sepsis.

Hepatoprotective potential of gabapentin in cecal ligation and puncture-induced sepsis; targeting oxidative stress, apoptosis, and NF-kB/MAPK signaling pathways

AIMS

Sepsis is a severe inflammatory response to infection with an incidence rate exceeding 48 million cases and 11 million sepsis-related deaths yearly. Furthermore, sepsis remains the fifth most common cause of death worldwide. The present study aimed to examine, for the first time, the potential hepatoprotective activity of gabapentin on cecal ligation and puncture (CLP)-induced sepsis in rats at the molecular level.

MAIN METHODS

CLP was used as a model of sepsis in male Wistar rats. Histological examination and liver functions were evaluated. Levels of MDA, GSH, SOD, IL-6, IL-1β, and TNF-α were investigated using ELISA. mRNA levels of Bax, Bcl-2, and NF-kB were assessed by qRT-PCR. Western blotting investigated the expression of ERK1/2, JNK1/2, and cleaved caspase 3 proteins.

KEY FINDINGS

CLP resulted in liver damage, elevated serum levels of ALT, AST, ALP, MDA, TNF-α, IL-6, and IL-1β, increased expression of ERK1/2, JNK1/2, and cleaved caspase 3 proteins, and upregulated Bax and NF-κB genes expression while it down-regulated Bcl-2 gene expression. However, gabapentin treatment significantly reduced the severity of CLP-induced biochemical, molecular, and histopathological changes. Gabapentin attenuated the levels of the proinflammatory mediators, decreased the expression of JNK1/2, ERK1/2, and cleaved caspase 3 proteins, suppressed Bax and NF-κB genes expression and increased the expression of the Bcl-2 gene.

SIGNIFICANCE

Consequently, Gabapentin reduced hepatic injury resulting from CLP-induced sepsis by reducing proinflammatory mediators, attenuating apoptosis, and inhibiting the intracellular MAPK (ERK1/2, JNK1/2)-NF-kB signaling pathway.

Acute Sepsis-Induced Cholestatic Disease Presenting With Isolated Hyper-Bilirubinemia

Sepsis-induced cholestatic disease occurs in a fair amount of critically-ill patients. Although the mechanism is poorly understood, hypoperfusion to the liver is one of the most common mechanisms that lead to liver dysfunction and subsequently biliary disease. Hepatic conditions such as cirrhosis and hepatitis A may have an impact on how sepsis-induced cholestatic disease can present. Understanding the presentation of sepsis-induced cholestasis and addressing the underlying cause of sepsis can certainly lead to better outcomes without the need for procedure intervention. We explore a patient with acute sepsis-induced cholestatic disease who had recently-resolving hepatitis A infection and underlying cirrhosis.

Tidy up - The unfolded protein response in sepsis

Pathogens, their toxic byproducts, and the subsequent immune reaction exert different forms of stress and damage to the tissue of the infected host. This stress can trigger specific transcriptional and post-transcriptional programs that have evolved to limit the pathogenesis of infectious diseases by conferring tissue damage control. If these programs fail, infectious diseases can take a severe course including organ dysfunction and damage, a phenomenon that is known as sepsis and which is associated with high mortality. One of the key adaptive mechanisms to counter infection-associated stress is the unfolded protein response (UPR), aiming to reduce endoplasmic reticulum stress and restore protein homeostasis. This is mediated via a set of diverse and complementary mechanisms, i.e. the reduction of protein translation, increase of protein folding capacity, and increase of polyubiquitination of misfolded proteins and subsequent proteasomal degradation. However, UPR is not exclusively beneficial since its enhanced or prolonged activation might lead to detrimental effects such as cell death. Thus, fine-tuning and time-restricted regulation of the UPR should diminish disease severity of infectious disease and improve the outcome of sepsis while not bearing long-term consequences. In this review, we describe the current knowledge of the UPR, its role in infectious diseases, regulation mechanisms, and further clinical implications in sepsis.

HLJ1 amplifies endotoxin-induced sepsis severity by promoting IL-12 heterodimerization in macrophages

Heat shock protein (HSP) 40 has emerged as a key factor in both innate and adaptive immunity, whereas the role of HLJ1, a molecular chaperone in HSP40 family, in modulating endotoxin-induced sepsis severity is still unclear. During lipopolysaccharide (LPS)-induced endotoxic shock, HLJ1 knockout mice shows reduced organ injury and IFN-γ (interferon-γ)-dependent mortality. Using single-cell RNA sequencing, we characterize mouse liver nonparenchymal cell populations under LPS stimulation, and show that HLJ1 deletion affected IFN-γ-related gene signatures in distinct immune cell clusters. In CLP models, HLJ1 deletion reduces IFN-γ expression and sepsis mortality rate when mice are treated with antibiotics. HLJ1 deficiency also leads to reduced serum levels of IL-12 in LPS-treated mice, contributing to dampened production of IFN-γ in natural killer cells but not CD4⁺ or CD8⁺ T cells, and subsequently to improved survival rate. Adoptive transfer of HLJ1-deleted macrophages into LPS-treated mice results in reduced IL-12 and IFN-γ levels and protects the mice from IFN-γ-dependent mortality. In the context of molecular mechanisms, HLJ1 is an LPS-inducible protein in macrophages and converts misfolded IL-12p35 homodimers to monomers, which maintains bioactive IL-12p70 heterodimerization and secretion. This study suggests HLJ1 causes IFN-γ-dependent septic lethality by promoting IL-12 heterodimerization, and targeting HLJ1 has therapeutic potential in inflammatory diseases involving activated IL-12/IFN-γ axis.

The liver in sepsis: molecular mechanism of liver failure and their potential for clinical translation

Liver failure is a life-threatening complication of infections restricting the host's response to infection. The pivotal role of the liver in metabolic, synthetic, and immunological pathways enforces limits the host's ability to control the immune response appropriately, making it vulnerable to ineffective pathogen resistance and tissue damage. Deregulated networks of liver diseases are gradually uncovered by high-throughput, single-cell resolved OMICS technologies visualizing an astonishing diversity of cell types and regulatory interaction driving tolerogenic signaling in health and inflammation in disease. Therefore, this review elucidates the effects of the dysregulated host response on the liver, consequences for the immune response, and possible avenues for personalized therapeutics.

Impact of Ursodeoxycholic Acid in Critically Ill Patients With Sepsis: A Retrospective Study

Background: Using ursodeoxycholic acid (UDCA) in critically ill patients as adjunctive therapy for sepsis/septic shock in neonates and children is controversial, while it has not been extensively investigated in adults. This study aims to assess the effect of UDCA use on the early resolution of sepsis/septic shock in critically ill adult patients. Method: A retrospective study of critically ill adult patients in the intensive care unit (ICU) admitted with sepsis/septic shock at King Abdulaziz Medical City. Based on their usage of UDCA, patients were categorized into two groups. A total of 88 patients were included for analysis after matching, based on severity of illness scores within 24-hours of ICU admission. The primary outcome was to assess the effect of UDCA on the severity and resolution of shock at day three of ICU admission. The secondary outcomes were 30-day in-hospital mortality, mechanical ventilation (MV) duration, and ICU length of stay (LOS). Results: Out of the 88 patients matched, 44 patients (50%) received UDCA during the study period. Using UDCA was neither associated with improvement in Sequential Organ Failure Assessment (SOFA) score ( p-value: 0.32), inotropes/vasopressors requirement ( p-value: 0.79), Glasgow Coma Scale (GCS) ( p-value: 0.59) nor total bilirubin levels ( p-value: 0.79) at day three compared with the control. There was a significant association between using UDCA and improvement in PaO2/FiO2 ratio ( p-value: 0.01) and early extubation at day three ( p-value: 0.04). Conclusion: Using UDCA in critically ill patients with sepsis/septic shock was not associated with improvement in shock severity and resolution. However, patients who received UDCA were more likely to be extubated and not require MV on day three of ICU admission.

Octanoic acid-rich enteral nutrition prevented lipopolysaccharide-induced acute liver injury through c-Jun N-terminal kinase-dependent autophagy

BACKGROUND

Acute liver injury (ALI) is an essential component of sepsis associated with poor outcomes. Octanoic acid (OA), a medium-chain fatty acid, has a protective effect on sepsis-induced organ damage, and autophagy is an adaptive response to sepsis. However, the underlying mechanism by which OA prevents ALI remains unknown. Therefore, we investigated whether OA-rich enteral nutrition (EN) prevented lipopolysaccharide (LPS)-induced ALI through the c-Jun N-terminal kinase (JNK)-dependent autophagy.

METHODS

Firstly, Sprague Dawley rats were randomly divided into four groups (sham, LPS, LPS + EN, and LPS + EN + OA) to detect the effect of OA-rich EN on LPS-induced ALI. Then, rats were randomly divided into five groups (sham, LPS, LPS + EN + OA, LPS + EN + OA + anisomycin (AN), and LPS + SP600125) to explore the mechanism by which OA-rich EN prevented ALI. EN and OA-rich EN were conducted through gastric tubes for 3 days. The liver protective effects were measured by liver histopathological changes, enzymes, inflammatory cytokines of serum and liver, the levels of autophagy, and JNK activity.

RESULTS

OA-rich EN inhibited JNK activity, up-regulated autophagy and prevented LPS-induced ALI. Inhibition of JNK activity conferred by SP promoted autophagy and prevented LPS-induced ALI. Moreover, the protective effect of autophagy and inhibition of JNK activity conferred by OA-rich EN on ALI was counteracted by AN.

CONCLUSION

OA-rich EN prevented LPS-induced ALI through JNK-dependent autophagy. This result suggested that OA-rich EN may be a therapeutic potential for ALI in patients with sepsis.

6-Shogaol Mitigates Sepsis-Associated Hepatic Injury through Transcriptional Regulation

Sepsis-associated liver dysfunction presents a significant public health problem. 6-Shogaol is the key bioactive component in dry ginger, which has antioxidant and anti-inflammation capacity. The present study aims to investigate the preventive effect of 6-shogaol on sepsis-induced liver injury. 6-Shogaol was administered to mice for 7 consecutive days before being intraperitoneally injected with lipopolysaccharide (LPS). After 24 h, mice were sacrificed, and biochemical and transcriptomic analyses were performed. Our results demonstrated that 6-shogaol prevented LPS-induced impairment in antioxidant enzymes and elevation in malondialdehyde level in the liver. The hepatic inflammatory response was significantly suppressed by 6-shogaol through suppressing the MAPK/NFκB pathway. RNA-sequencing data analysis revealed that 41 overlapped genes between the LPS vs. control group and 6-shogaol vs. LPS group were identified, among which 36 genes were upregulated, and 5 genes were downregulated for the LPS vs. control group. These overlapped genes are enriched in inflammation-related pathways, e.g., TNF and NFκB. The mRNA expression of the overlapped genes was also verified in the LPS-induced BRL-3A cell model. In summary, 6-shogaol shows great potential as a natural chemopreventive agent to treat sepsis-associated hepatic disorders.

De Ritis Ratio as a Significant Prognostic Factor in Patients with Sepsis: A Retrospective Analysis

PURPOSE

This study was performed to investigate the relationship between the aspartate transaminase and/or alanine transaminase ratio (DRR) and long-term mortality of patients diagnosed with sepsis or septic shock.

MATERIALS AND METHODS

We conducted a retrospective study among adult septic patients who were admitted to the surgical intensive care unit (ICU) of the Chinese People's Liberation Army (PLA) General Hospital from January 2014 to December 2018. Baseline characteristics were compared between survivors and non survivors. We performed univariate and multivariate Cox regression analyses to evaluate the relation of DRR with 180-day mortality. The potential prognostic value of DRR in predicting mortality rate was assessed by receiver operating characteristic (ROC) curve analysis. In addition, we conducted subgroup analysis by the optimal DRR cutoff value.

RESULTS

We included a total of 183 patients in the current study, and 44 (24%) patients died within 180 days of hospitalization. Univariate and multivariate Cox analyses revealed that DRR was an independent predictor of 180-day mortality (hazard ratio [HR] 1.421, 95% confidence interval [CI] 1.073-1.883, P = 0.014). The predictive accuracy of DRR for 180-day mortality was presented as an ROC curve, which had an area under the curve (AUC) of 0.708 (95% CI 0.629-0.786, P < 0.001). After we stratified all enrolled patients into two groups by using the optimal cutoff value of 1.29, we observed a significantly higher mortality in patients with a relatively high DRR.

CONCLUSIONS

An elevated DRR was associated with higher 180-day mortality among septic patients, and DRR might be an optimal marker for predicting the long-term mortality of sepsis. More prospective and randomized trials are needed to confirm the prognostic value of DRR.

Sites and Causes of Infection in Patients with Sepsis-Associated Liver Dysfunction: A Population Study from the Medical Information Mart for Intensive Care III

BACKGROUND Little is known about the relationship between the site of infection, type of pathogen, and the occurrence of sepsis-associated liver dysfunction (SALD). This population study aimed to identify the sites and types of infection in SALD patients. MATERIAL AND METHODS We conducted a retrospective observational study using the Medical Information Mart for Intensive Care III. Patients with sepsis were divided into a SALD group and a control group. We evaluated the effect of the location of culture-positive specimens and the distribution of pathogens on the occurrence of SALD and then compared the clinical outcomes. RESULTS A total of 14 596 admissions were included, and the incidence of SALD was 11.96%. Positive bile culture (odds ratio [OR] 7.450, P<0.001), peritoneal fluid culture (OR 3.616, P<0.001), and blood culture (OR 1.957, P<0.001) were correlated with the occurrence of SALD. Infection with Enterococcus faecium (OR 3.065, P<0.001), Bacteroides fragilis (OR 2.061, P<0.001), Klebsiella oxytoca (OR 2.066, P<0.001), Enterobacter aerogenes (OR 1.92, P=0.001), and Aspergillus fumigatus (OR 2.144, P=0.001) were correlated with the occurrence of SALD. The Intensive Care Unit mortality and hospital mortality were higher in the SALD group than in the control group (24.7% vs 9.0%, P<0.001; 34.2% vs 13.8%, P<0.001, respectively). CONCLUSIONS SALD should be considered for patients with sepsis whose infection site is the biliary system, abdominal cavity, or blood and the pathogen is Enterococcus faecium, B. fragilis, K. oxytoca, Enterobacter aerogenes, or A. fumigatus. When SALD occurs in patients with sepsis, the above infection sites and pathogens should be considered first.

Gadolinium Chloride Inhibits the Production of Liver Interleukin-27 and Mitigates Liver Injury in the CLP Mouse Model

BACKGROUND

Liver macrophages play an important regulatory role in the inflammatory response of liver injury after severe infection. Interleukin- (IL-) 27 is an inflammatory cytokine that plays an important role in diseases caused by bacterial infection. However, the relationship between IL-27 and liver macrophages in liver injury after severe infection is not yet clear.

METHODS

A cecal ligation puncture (CLP) model was established in wild-type (WT) and IL-27 receptor- (WSX-1-) deficient (IL-27r-/-) mice, and recombinant IL-27 and gadolinium chloride (GdCl3) were injected into WT mice in the designated groups. The serum and liver IL-27, IL-6, tumor necrosis factor alpha (TNF-α), and IL-1β expression levels were evaluated by ELISA, quantitative PCR, or Western blotting; serum ALT and AST were detected by detection kits; and the severity of liver damage was evaluated by hematoxylin and eosin staining and the TUNEL assay of the liver tissue from the different groups. Liver macrophage polarization was evaluated by immunofluorescence. In addition, the polarization of peritoneal macrophage was evaluated by flow cytometry.

RESULTS

The serum and liver IL-27 expression levels were elevated in WT mice after CLP-induced severe infection, which were consistent with the changes in HE scores in the liver tissue. The levels of serum ALT, AST, liver IL-6, TNF-α, and IL-1β mRNA and liver pathological injury scores were further increased when pretreated with recombinant IL-27 in WT mice, but these levels were decreased in IL-27r-/- mice after CLP-induced severe infection compared to WT mice. In WT mice pretreated with GdCl3, liver pathological scores, serum ALT and AST, TUNEL-positive cell proportion from liver tissues, liver IL-27 expression, and the liver macrophages M1 polarization proportion decreased after CLP; however, the serum IL-27, IL-6, TNF-α, and IL-1β levels and the pathological lung and kidney scores were not significantly changed. When supplemented with exogenous IL-27, the liver pathological scores, serum ALT, AST, TUNEL-positive cell proportion of liver tissues, liver IL-27 expression, and the liver macrophage M1 polarization proportion increased. The in vitro, IL-27 expression increased in peritoneal macrophages when stimulated with LPS. Recombinant IL-27 together with LPS promoted the elevations in IL-6, TNF-α, and IL-1β levels in supernatant and the M1 polarization of peritoneal macrophages.

CONCLUSION

IL-27 is an important cytokine in the inflammatory response to liver injury after severe infection. The reduction of liver injury by gadolinium chloride in severe infection mice models may relate to the inhibition of liver IL-27 production. These changes may be mainly related to the decrease of liver macrophages M1 polarization. IL-27 may have a positive feedback on these macrophages.

P2X7 receptor deletion attenuates oxidative stress and liver damage in sepsis

Sepsis is a severe disease characterized by an uncontrolled systemic inflammation and consequent organ dysfunction generated in response to an infection. Extracellular ATP acting through the P2X7 receptor induces the maturation and release of pro-inflammatory cytokines (i.e., IL-1β) and the production of reactive nitrogen and oxygen species that lead to oxidative tissue damage. Here, we investigated the role of the P2X7 receptor in inflammation, oxidative stress, and liver injury in sepsis. Sepsis was induced by cecal ligation and puncture (CLP) in wild-type (WT) and P2X7 knockout (P2X7^-/-) mice. The oxidative stress in the liver of septic mice was assessed by 2',7'-dichlorofluorescein oxidation reaction (DCF), thiobarbituric acid-reactive substances (TBARS), and nitrite levels dosage. The status of the endogenous defense system was evaluated through catalase (CAT) and superoxide dismutase (SOD) activities. The inflammation was assessed histologically and by determining the expression of inflammatory cytokines and chemokines by RT-qPCR. We observed an increase in the reactive species and lipid peroxidation in the liver of septic WT mice, but not in the liver from P2X7^-/- animals. We found an imbalance SOD/CAT ratio, also only WT septic animals. The number of inflammatory cells and the gene expression of IL-1 β, IL-6, TNF-α, IL-10, CXCL1, and CXCL2 were higher in the liver of WT septic mice in comparison to P2X7^-/- septic animals. In summary, our results suggest that the P2X7 receptor might be a therapeutic target to limit oxidative stress damage and liver injury during sepsis.

Comparison of the trometamol-balanced solution with two other crystalloid solutions for fluid resuscitation of a rat hemorrhagic model

Currently, the optimal resuscitation fluid remains debatable. Therefore, in the present study, we designed a trometamol-balanced solution (TBS) for use as a resuscitation fluid for hemorrhagic shock. Hemorrhagic shock was induced in 18 male Wistar-Kyoto rats, which were assigned to normal saline (NS), Ringer's solution (RS), and TBS groups. During the hemorrhagic state, their hemodynamic parameters were recorded using an Abbott i-STAT analyzer with the CG4+ cartridge (for pH, pressure of carbon dioxide, pressure of oxygen, total carbon dioxide, bicarbonate, base excess, oxygen saturation, and lactate), the CG6+ cartridge (for sodium, potassium, chloride, blood glucose, blood urea nitrogen, hematocrit, and hemoglobin), and enzyme-linked immunosorbent assay kits (calcium, magnesium, creatinine, aspartate aminotransferase, alanine aminotransferase, bilirubin, and albumin). Similar trends were found for the parameters of biochemistries, electrolytes, and blood gas, and they revealed no significant changes after blood withdrawal-induced hemorrhagic shock. However, the TBS group showed more effective ability to correct metabolic acidosis than the NS and RS groups. TBS was a feasible and safe resuscitation solution in this study and may be an alternative to NS and RS for resuscitation in hemorrhagic shock patients without liver damage.

Monocyte upregulation of podoplanin during early sepsis induces complement inhibitor release to protect liver function

Multiple organ failure in sepsis is a progressive failure of several interdependent organ systems. Liver dysfunction occurs early during sepsis and is directly associated with patient death; however, the underlying mechanism of liver dysfunction is unclear. Platelet transfusion benefits patients with sepsis, and inhibition of complement activation protects liver function in septic animals. Herein, we explored the potential link between platelets, complement activation, and liver dysfunction in sepsis. We found that deletion of platelet C-type lectin-like receptor 2 (CLEC-2) exacerbated liver dysfunction in early sepsis. Platelet CLEC-2-deficient mice exhibited higher complement activation, more severe complement attack in the liver, and lower plasma levels of complement inhibitors at early time points after E. coli infection. Circulating monocytes expressed the CLEC-2 ligand podoplanin in early sepsis, and podoplanin binding induced release of complement inhibitors from platelets. Injection of complement inhibitors released from platelets reduced complement attack and attenuated liver dysfunction in septic mice. These findings indicate a new function of platelets in the regulation of complement activation during sepsis.

Puerarin Increases Survival and Protects Against Organ Injury by Suppressing NF-κB/JNK Signaling in Experimental Sepsis

Puerarin, an isoflavonoid rich in Radix Puerariae, has been reported to be a broadly effective regulator in various biological processes and clinic conditions. However, the role of puerarin in sepsis-induced mortality with multiple-organ injury remains unknown. Herein, we showed that puerarin potently attenuated organ injury and increased survival rate in both lipopolysaccharides (LPS) and cecal ligation and puncture (CLP) induced mouse sepsis models. It greatly suppressed systemic inflammation, determined by the serum levels of proinflammatory factors TNF-α, IL-6, IL-1β, IL-10, as well as monocyte chemotactic protein-1 (MCP-1) and C-reactive protein (CRP). Flow cytometry analysis indicated that puerarin settled overall inflammation mainly by normalizing expanded macrophages with limited effects on dendritic cells and CD4+T cells in the circulation of sepsis mice. In the liver, puerarin inhibited the transcription of inflammatory factor TNF-α, IL-6, and IL-1β and protected hepatocyte apoptosis in sepsis mouse models. In vitro, puerarin inhibited LPS-induced inflammation in LO2 hepatocytes, prevented TNF-α-mediated cell apoptosis and promoted an M2 phenotype revealed by M2 marker IL-10 and Arginase-1 (Arg-1) in LPS challenged Raw 264.7 macrophages, through the inhibition of TLR4/NF-κB/JNK pathway. In conclusion, puerarin reduced systemic inflammation and protected organ injury in sepsis mice, thus, it might provide a new modality for a better treatment of sepsis.

Antecedent Dietary Glutamine Supplementation Benefits Modulation of Liver Pyroptosis in Mice with Polymicrobial Sepsis

The liver is the main organ responsible for bacterial and endotoxin clearance. Pyroptosis is a form of proinflammatory programmed cell death activated by caspase-1/11 and gasdermin D (GadD). Pyroptosis protects the host against bacterial infection; however, overactive pyroptosis can lead to organ injury. Glutamine (GLN) is a specific amino acid with anti-inflammatory and immunomodulatory properties. This study investigated the effects of GLN pretreatment on liver pyroptosis in a mouse model of polymicrobial sepsis. Mice were assigned to sham, sepsis control (Sepsis-C), and sepsis GLN (Sepsis-G) groups. The sham and Sepsis-C groups were fed the AIN-93G diet. The Sepsis-G group was provided with identical diet components except that part of the casein was replaced by GLN. After feeding the respective diets for 2 weeks, a cecal ligation and puncture (CLP) procedure was performed in the sepsis groups. An antibiotic was administered after CLP. Mice were sacrificed at either 24 or 72 h after CLP. The results showed that sepsis resulted in upregulated liver caspase-1/11 expression. Compared to the Sepsis-C group, the Sepsis-G group had higher liver caspase-11 and NLRP3 gene expressions at 24 h and lower active caspase-1/11 and cleaved GadD protein levels at 72 h after sepsis. Additionally, liver inflammatory cytokine gene expressions had decreased by 72 h post-CLP. The findings suggest that prophylactic administration of GLN initially upregulated liver pyroptosis to eradicate pathogens, yet the process of pyroptosis was suppressed in the late phase of sepsis. This may have beneficially attenuated liver inflammation and injury in an antibiotic-treated septic condition.

Hepatocyte-Specific Deletion of AMPKα1 Results in Worse Outcomes in Mice Subjected to Sepsis in a Sex-Specific Manner

Alterations in the energy homeostasis contribute to sepsis-mediated multiple organ failure. The liver plays a central role in metabolism and participates to the innate immune and inflammatory responses of sepsis. Several clinical and experimental studies have suggested that females are less susceptible to the adverse outcome of sepsis. However, underlying mechanisms of organ damage in sepsis remain largely undefined. AMP-activated protein kinase (AMPK) is an important regulator of mitochondrial quality control. The AMPK catalytic α1 isoform is abundantly expressed in the liver. Here, we determined the role of hepatocyte AMPKα1 in sepsis by using hepatocyte-specific AMPKα1 knockout mice (H-AMPKα1 KO) generated with Cre-recombinase expression under the control of the albumin promoter. Using a clinically relevant model of polymicrobial sepsis by cecal ligation and puncture (CLP), we observed that male H-AMPKα1 KO mice had higher plasma levels of tumor necrosis factor-α and interleukin-6 and exhibited a more severe liver and lung injury than male H-AMPKα1 WT mice, as evaluated by histology and neutrophil infiltration at 18 h after CLP. Plasma levels of interleukin-10 and the keratinocyte-derived chemokine were similarly elevated in both KO and WT male mice. At transmission electron microscopy analysis, male H-AMPKα1 KO mice exhibited higher liver mitochondrial damage, which was associated with a significant decrease in liver ATP levels when compared to WT mice at 18 h after sepsis. Mortality rate was significantly higher in the male H-AMPKα1 KO group (91%) when compared to WT mice (60%) at 7 days after CLP. Female H-AMPKα1 WT mice exhibited a similar degree of histological liver and lung injury, but significantly milder liver mitochondrial damage and higher autophagy when compared to male WT mice after CLP. Interestingly, H-AMPKα1 KO female mice had lower organ neutrophil infiltration, lower liver mitochondrial damage and lower levels of cytokines than WT female mice. There was no significant difference in survival rate between WT and KO mice in the female group. In conclusion, our study demonstrates that AMPKα1 is a crucial hepatoprotective enzyme during sepsis. Furthermore, our results suggest that AMPK-dependent liver metabolic functions may influence the susceptibility to multiple organ injury in a sex-dependent manner.

NF-κB RelA Is Required for Hepatoprotection during Pneumonia and Sepsis

Pneumonia and sepsis are distinct but integrally linked public health concerns. The hepatic acute-phase response (APR), which is largely dependent on transcription factors NF-κB RelA and STAT3, is a hallmark of these pathologies and other injurious conditions. Inactivation of the APR can promote liver injury, a frequently observed organ dysfunction during sepsis. However, whether or how the acute-phase changes promote liver tissue resilience during infections is unclear. To determine the hepatoprotective role of the hepatic APR, we utilized mice bearing hepatocyte-specific deletions of either RelA or STAT3. Mice were challenged intratracheally (i.t.), intravenously (i.v.), or intraperitoneally (i.p.) with Escherichia coli, Klebsiella pneumoniae, Streptococcus pneumoniae, lipopolysaccharide (LPS), or alpha-galactosylceramide (αGalCer) to induce pneumonia, sepsis, or NKT cell activation. Liver injury was observed in RelA-null (hepRelAΔ/Δ) mice but not STAT3-null (hepSTAT3Δ/Δ) mice during pneumonia. The absence of RelA resulted in hepatotoxicity across several models of pneumonia, sepsis, and NKT cell activation. Injury was associated with increased levels of activated caspase-3 and -8 and substantial alteration of the hepatic transcriptome. Hepatotoxicity in the absence of RelA could be reversed by neutralization of tumor necrosis factor alpha (TNF-α). These results indicate the requirement of RelA-dependent inducible hepatoprotection during pneumonia and sepsis. Further, the results demonstrate that RelA-dependent gene programs are critical for maintaining liver homeostasis against TNF-α-driven immunotoxicity.

Multimorbidity states associated with higher mortality rates in organ dysfunction and sepsis: a data-driven analysis in critical care

BACKGROUND

Sepsis remains a complex medical problem and a major challenge in healthcare. Diagnostics and outcome predictions are focused on physiological parameters with less consideration given to patients' medical background. Given the aging population, not only are diseases becoming increasingly prevalent but occur more frequently in combinations ("multimorbidity"). We hypothesized the existence of patient subgroups in critical care with distinct multimorbidity states. We further hypothesize that certain multimorbidity states associate with higher rates of organ failure, sepsis, and mortality co-occurring with these clinical problems.

METHODS

We analyzed 36,390 patients from the open source Medical Information Mart for Intensive Care III (MIMIC III) dataset. Morbidities were defined based on Elixhauser categories, a well-established scheme distinguishing 30 classes of chronic diseases. We used latent class analysis to identify distinct patient subgroups based on demographics, admission type, and morbidity compositions and compared the prevalence of organ dysfunction, sepsis, and inpatient mortality for each subgroup.

RESULTS

We identified six clinically distinct multimorbidity subgroups labeled based on their dominant Elixhauser disease classes. The "cardiopulmonary" and "cardiac" subgroups consisted of older patients with a high prevalence of cardiopulmonary conditions and constituted 6.1% and 26.4% of study cohort respectively. The "young" subgroup included 23.5% of the cohort composed of young and healthy patients. The "hepatic/addiction" subgroup, constituting 9.8% of the cohort, consisted of middle-aged patients (mean age of 52.25, 95% CI 51.85-52.65) with the high rates of depression (20.1%), alcohol abuse (47.75%), drug abuse (18.2%), and liver failure (67%). The "complicated diabetics" and "uncomplicated diabetics" subgroups constituted 9.4% and 24.8% of the study cohort respectively. The complicated diabetics subgroup demonstrated higher rates of end-organ complications (88.3% prevalence of renal failure). Rates of organ dysfunction and sepsis ranged 19.6-69% and 12.5-46.7% respectively in the six subgroups. Mortality co-occurring with organ dysfunction and sepsis ranges was 8.4-23.8% and 11.7-27.4% respectively. These adverse outcomes were most prevalent in the hepatic/addiction subgroup.

CONCLUSION

We identify distinct multimorbidity states that associate with relatively higher prevalence of organ dysfunction, sepsis, and co-occurring mortality. The findings promote the incorporation of multimorbidity in healthcare models and the shift away from the current single-disease paradigm in clinical practice, training, and trial design.

Plasma exchange improves outcome of sepsis-associated liver failure: A case report

RATIONALE

Sepsis-associated liver failure is characterized by increased bilirubin levels and coagulation disorders, which has a significant impact on mortality due to the insufficient understanding of its complicated pathogenesis pathophysiology and a lack of standardized treatment.

PATIENT CONCERNS

A 56-year-old woman presented signs of sepsis on the 2nd day after undergoing ureteroscopy for left ureter and laparoscopy for lysis of adhesions around left ureter due to hydronephrosis. Her condition seemed to have been improved after treatment, but the bilirubin levels suddenly increased drastically with presence of coagulation disorders.

DIAGNOSIS

Laboratory tests combined with her medical history confirmed the diagnosis as sepsis-associated liver failure.

INTERVENTIONS

Plasma exchange was applied after hepatoprotective drugs, and other supportive therapies were given which did not significantly improve the condition.

OUTCOMES

Laboratory liver function tests indicated the restoration of damaged liver function after plasma exchange was performed and the patient was soon transferred from intensive care unit back to the general ward.

LESSONS

Plasma exchange might be a vital and effective therapy to improve outcome of sepsis associated liver failure especially when conventional support therapy is ineffective.

A novel role for programmed cell death receptor ligand 2 in sepsis-induced hepatic dysfunction

The liver is an organ that, when dysfunctional in a septic patient, is strongly associated with morbidity and mortality. Understanding the pathophysiology of liver failure during sepsis may lead to improved diagnostics and potential therapeutic targets. Historically, programmed cell death receptor (PD) ligand 1 (PD-L1) has been considered the primary ligand for its checkpoint molecule counterpart, PD-1, with PD-L2 rarely in the immunopathological spotlight. PD-1 and PD-L1 contribute to liver dysfunction in a murine cecal ligation and puncture (CLP) model of sepsis, but virtually nothing is known about PD-L2's role in sepsis. Therefore, our central hypothesis was that sepsis-induced changes in hepatic PD-L2 expression contributed to worsened liver function and, subsequently, more pronounced morbidity and mortality. We found that although PD-L1 gene deficiency attenuated the hepatic dysfunction seen in wild-type mice after CLP, the loss of PD-L2 appeared to actually worsen indices of liver function along with a trend toward higher liver tissue vascular permeability. Conversely, some protective effects of PD-L2 gene deletion were noted, such as reduced liver/peritoneal bacterial load and reduced IL-6, IL-10, and macrophage inflammatory protein 2 levels following CLP. These diverse actions, as well as the unique expression pattern of PD-L2, may explain why no overt survival advantage could be witnessed in the septic PD-L2^-/- mice. Taken together, these data suggest that although PD-L2 has some selective effects on the hepatic response seen in the septic mouse, these factors are not sufficient to alter septic mortality in this adult murine model. NEW & NOTEWORTHY Our study shows not only that ligands of the checkpoint protein PD-1 respond inversely to a stressor such as septic challenge (PD-L2 declines, whereas PD-L1 rises) but also that aspects of liver dysfunction increase in septic mice lacking the PD-L2 gene. Furthermore, these differences in PD-L2 gene-deficient animals culminated in the abrogation of the survival advantage seen in the septic PD-L1-knockout mice, suggesting that PD-L2 may have roles beyond a simple immune tolerogen.

Treatment of AECHB and Severe Hepatitis (Liver Failure)

This chapter describes the general treatment and immune principles and internal management for AECHB and HBV ACLF, including ICU monitoring, general supportive medications/nutrition/nursing, immune therapy, artificial liver supportive systems, hepatocyte/stem cell, and liver transplant, management for special populations, frequently clinical complications and the utilization of Chinese traditional medicines.

Early clinical indicators of severe hepatitis B include acratia, gastrointestinal symptoms, a daily increase in serum bilirubin >1 mg/dL, toxic intestinal paralysis, bleeding tendency and mild mind anomaly or character change, and the presence of other diseases inducing severe hepatitis. Laboratory indicators include T-Bil, PTA, cholinesterase, pre-albumin and albumin. The roles of immune indicators (such as IL-6, TNF-α, and fgl2), gene polymorphisms, HBV genotypes, and gene mutations as early clinical indicators.

Intensive Care Unit monitor patients with severe hepatitis include intracranial pressure, infection, blood dynamics, respiratory function, renal function, blood coagulation function, nutritional status and blood purification process. Nursing care should not only include routine care, but psychological and special care (complications).

Nutrition support and nursing care should be maintained throughout treatment for severe hepatitis. Common methods of evaluating nutritional status include direct human body measurement, creatinine height index (CHI) and subject global assessment of nutrition (SGA). Malnourished patients should receive enteral or parenteral nutrition support.

Immune therapies for severe hepatitis include promoting hepatocyte regeneration (e.g. with glucagon, hepatocyte growth factor and prostaglandin E1), glucocorticoid suppressive therapy, and targeting molecular blocking. Corticosteroid treatment should be early and sufficient, and adverse drug reactions monitored. Treatments currently being investigated are those targeting Toll-like receptors, NK cell/NK cell receptors, macrophage/immune coagulation system, CTLA-4/PD-1 and stem cell transplantation.

In addition to conventional drugs and radioiodine, corticosteroids and artificial liver treatment can also be considered for severe hepatitis patients with hyperthyreosis. Patients with gestational severe hepatitis require preventive therapy for fetal growth restriction, and it is necessary to choose the timing and method of fetal delivery. For patients with both diabetes and severe hepatitis, insulin is preferred to oral antidiabetic agents to control blood glucose concentration. Liver toxicity of corticosteroids and immune suppressors should be monitored during treatment for severe hepatitis in patients with connective tissue diseases including SLE, RA and sicca syndrome. Patient with connective tissue diseases should preferably be started after the antiviral treatment with nucleos(t)ide analogues.

An artificial liver can improve patients’ liver function; remove endotoxins, blood ammonia and other toxins; correct amino acid metabolism and coagulation disorders; and reverse internal environment imbalances. Non-bioartificial livers are suitable for patients with early and middle stage severe hepatitis; for late-stage patients waiting for liver transplantation; and for transplanted patients with rejection reaction or transplant failure. The type of artificial liver should be determined by each patient’s condition and previous treatment purpose, and patients should be closely monitored for adverse reactions and complications. Bio- and hybrid artificial livers are still under development.

MELD score is the international standard for choosing liver transplantation. Surgical methods mainly include the in situ classic type and the piggyback type; transplantation includes no liver prophase, no liver phase or new liver phase. Preoperative preparation, management of intraoperative and postoperative complications and postoperative long-term treatment are keys to success.

Severe hepatitis belongs to the categories of “acute jaundice”, “scourge jaundice”, and “hot liver” in traditional Chinese medicine. Treatment methods include Chinese traditional medicines, acupuncture and acupoint injection, external application of drugs, umbilical compress therapy, drip, blow nose therapy, earpins, and clysis. Dietary care is also an important part of traditional Chinese medicine treatment.

Short-term use of MyD88 inhibitor TJ-M2010-5 prevents d-galactosamine/lipopolysaccharide-induced acute liver injury in mice

Excessive activation of the TLR/MyD88 signaling pathway contributes to several inflammation-related diseases. Previously, our laboratory synthesized a novel thiazaol-aminoramification MyD88 inhibitor named TJ-M2010-5. In this study, we interrogated the role of MyD88, as well as the protective effect of TJ-M2010-5, in a d-gal/LPS-induced acute liver injury mouse model. In order to induce acute liver injury, BALB/c mice received intraperitoneal injection of d-gal and LPS at a dose of 800 mg/kg and 80 μg/kg body weight, respectively. All mice died within 48 h of injection without intervention. However, pre-treatment with TJ-M2010-5 as well as knock-out (KO) of the MyD88 gene significantly improved mouse survival rate to 73.3% and 80% at 48 h, respectively, and both treatments protected liver function. These pathological results demonstrated that TJ-M2010-5 and MyD88 KO reduced the infiltration of inflammatory cells and protected hepatocytes against apoptosis. Furthermore, TJ-M2010-5 remarkably inhibited NF-κB and MAPK signaling in vivo. LPS-induced activation of macrophages as well as pro-inflammatory factors were also shown to be decreased after TJ-M2010-5 treatment in vivo and in vitro. Taken together, these results suggested that blockage of the TLR/MyD88 signaling pathway by TJ-M2010-5 has an important role in the prevention of inflammation-related acute liver injury.

Overexpression of homeodomain-interacting protein kinase 2 (HIPK2) attenuates sepsis-mediated liver injury by restoring autophagy

Sepsis is the leading cause of death in intensive care units worldwide. Autophagy has recently been shown to protect against sepsis-induced liver injury. Here, we investigated the roles of homeodomain-interacting protein kinase 2 (HIPK2) in the molecular mechanism of sepsis-induced liver injury. HIPK2 expression was reduced in sepsis-induced liver injury, and HIPK2 overexpression increased the survival rate and improved caecal ligation and puncture (CLP)-induced liver injury by reducing serum and liver aspartate transaminase (AST), alanine transaminase (ALT), and alkaline phosphatase (ALP) levels in mice with sepsis. HIPK2 overexpression significantly decreased CLP-induced release of inflammatory cytokines into the serum and attenuated oxidative stress-associated indicators in mice with CLP-induced liver injury, whereas HIPK2 knockdown produced the opposite results, suggesting that HIPK2 is a negative regulator of sepsis. Furthermore, HIPK2 overexpression inhibited lipopolysaccharide (LPS)-induced apoptosis of primary hepatocytes, increased the autophagic flux, and restored both autophagosome and autolysosome formation in the livers of CLP-induced mice by suppressing calpain signalling. Importantly, HIPK2 overexpression reduced the elevated cytosolic Ca²⁺ concentration in LPS-treated primary hepatocytes by interacting with calpain 1 and calmodulin. Finally, several anti-inflammatory drugs, including resveratrol, aspirin, vitamin E and ursolic acid, significantly increased the levels of the HIPK2 mRNA and protein by modulating promoter activity and the 3′-UTR stability of the HIPK2 gene. In conclusion, HIPK2 overexpression may improve sepsis-induced liver injury by restoring autophagy and thus might be a promising target for the clinical treatment of sepsis.

Sophocarpine Attenuates LPS-Induced Liver Injury and Improves Survival of Mice through Suppressing Oxidative Stress, Inflammation, and Apoptosis

Septic liver injury/failure that is mainly characterized by oxidative stress, inflammation, and apoptosis led to a great part of terminal liver pathology with limited effective intervention. Here, we used a lipopolysaccharide (LPS) stimulation model to simulate the septic liver injury and investigated the effect of sophocarpine on LPS-stimulated mice with endotoxemia. We found that sophocarpine increases the survival rate of mice and attenuates the LPS-induced liver injury, which is indicated by pathology and serum liver enzymes. Further research found that sophocarpine ameliorated hepatic oxidative stress indicators (H₂O₂, O₂^∙−, and NO) and enhanced the expression of antioxidant molecules such as superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH). In addition, sophocarpine also attenuated regional and systematic inflammation and further reduced apoptosis of hepatocytes. Mechanistic evidence was also investigated in the present study as sophocarpine inhibited hepatic expression of the CYP2E/Nrf2 pathway during oxidative stress, inactivated p38/JNK cascade and NF-κB pathway, and, meanwhile, suppressed PI3K/AKT signaling that reduced apoptosis. Conclusively, the present study unveiled the protective role of sophocarpine in LPS-stimulated oxidative reaction, inflammation, and apoptosis by suppressing the CYP2E/Nrf2/ROS as well as PI3K/AKT pathways, suggesting its promising role in attenuating inflammation and liver injury of septic endotoxemia.

Rational design of peptide derivatives for inhibition of MyD88-mediated toll-like receptor signaling in human peripheral blood mononuclear cells and epithelial cells exposed to Francisella tularensis

Small molecules were developed to attenuate proinflammatory cytokines resulting from activation of MyD88-mediated toll-like receptor (TLR) signaling by Francisella tularensis. Fifty-three tripeptide derivatives were synthesized to mimic a key BB-loop region involved in toll-like/interleukin-1 receptor recognition (TIR) domain interactions. Compounds were tested for inhibition of TNF-α, IFN-γ, IL-6, and IL-1β in human peripheral blood mononuclear cells (PBMCs) and primary human bronchial epithelial cells exposed to LPS extracts from F. tularensis. From 53 compounds synthesized and tested, ten compounds were identified as effective inhibitors of F. tularensisLPS-induced cytokines. Compound stability testing in the presence of human liver microsomes and human serum resulted in the identification of tripeptide derivative 7 that was a potent, stable, and drug-like small molecule. Target corroboration using a cell-based reporter assay and competition experiments with MyD88 TIR domain protein supported that the effect of 7 was through MyD88 TIR domain interactions. Compound 7 also attenuated proinflammatory cytokines in human peripheral blood mononuclear cells and bronchial epithelial cells challenged with a live vaccine strain of F. tularensis at a multiplicity of infection of 1:5. Small molecules that target TIR domain interactions in MyD88-dependent TLR signaling represent a promising strategy toward host-directed adjunctive therapeutics for inflammation associated with biothreat agent-induced sepsis.

Evaluation of an ADVanced Organ Support (ADVOS) system in a two-hit porcine model of liver failure plus endotoxemia

Background

Novel extracorporeal procedures are constantly being developed and evaluated for use in patients with sepsis. Preclinical evaluation of such procedures usually requires testing in large animal models. In the present work, the safety and efficacy of a recently developed ADVanced Organ Support (ADVOS) system in a newly developed large animal two-hit model of liver failure combined with endotoxemia were tested.

Methods

After establishing the model in more than 50 animals, a randomized study was performed. An inflammatory cholestatic liver injury was initially provoked in pigs. Three days after surgery, endotoxin was gradually administered during 7½ h. Animals were randomized to receive standard medical treatment either with (ADVOS group, n = 5) or without ADVOS (control group, n = 5). The ADVOS treatment was started 2½ h after endotoxemia and continued for 7 h. Survival, cardiovascular, respiratory, renal, liver, coagulation, and cerebral parameters were analyzed.

Results

Three days after surgery, cholestatic injury resulted in hyperbilirubinemia [5.0 mg/dl (IQR 4.3–5.9 mg/dl)], hyperammonemia [292 μg/dl (IQR 291–296 μg/dl)], leukocytosis [20.2 10³/μl (IQR 17.7–21.8 10³/μl)], and hyperfibrinogenemia [713 mg/dl (IQR 654–803 mg/dl)]. After endotoxemia, the ADVOS procedure stabilized cardiovascular, respiratory, and renal parameters and eliminated surrogate markers as bilirubin [2.3 (IQR 2.3–3.0) vs. 5.5 (IQR 4.6–5.6) mg/dl, p = 0.001] and creatinine [1.4 (IQR 1.1–1.7) vs. 2.3 (IQR 2.1–3.1) mg/dl, p = 0.01]. Mortality: All animals in the ADVOS group survived, while all animals in the control group expired during the 10-h observation period (p = 0.002). No adverse events related to the procedure were observed.

Conclusions

The ADVOS procedure showed a promising safety and efficacy profile and improved survival in a sepsis-like animal model with dysfunction of multiple organs. An amelioration of major organ functions (heart and lung) combined with removal of markers for kidney and liver function was observed.

Electronic supplementary material

The online version of this article (doi:10.1186/s40635-017-0144-3) contains supplementary material, which is available to authorized users.

Intraperitoneal gardiquimod protects against hepatotoxicity through inhibition of oxidative stress and inflammation in mice with sepsis

Many reports recapitulate the contribution of reactive oxygen species (ROS) over-accumulation to the organ damage; it is of significance to strictly target ROS production. In this study, we evaluated the potential role of TLR7 agonist gardiquimod (GDQ) in oxidative stress (OS) in liver injury induced by sepsis. Here, we observed that intraperitoneal pretreatment with GDQ dramatically elevated the septic survival rate and effectively attenuated the septic liver injury. Interestingly, the increased ROS and inflammatory factor IL-6 levels were reversed after GDQ intervention. Subsequently, Western blot was employed to determine the definite mechanism. As expected, it was showed that the upregulation of c-Jun N-terminal kinase (JNK)/c-Jun pathway in liver of septic animals was considerably suppressed by GDQ pre-exposure. Our current result highlight that pre-administration of GDQ ameliorated sepsis induced hepatotoxicity and reduced the generation of IL-6 and OS responses, which was associated with downregulation of JNK/c-Jun pathway. Our strategies might be ultimately beneficial in mitigating liver injury symptom.

Hepatic hepcidin protects against polymicrobial sepsis in mice by regulating host iron status

BACKGROUND

Hepcidin is a master regulator of iron metabolism primarily produced by the liver. Markedly increased hepcidin levels have been observed in septic individuals, while decreased hepatic hepcidin expression has been demonstrated in liver diseases that tend to develop into sepsis. However, the role of liver hepcidin in sepsis remains unknown.

METHODS

Mouse hepatic hepcidin expression was silenced using adenovirus-mediated hepcidin-specific short hairpin RNA injected via the tail vein. Sepsis was induced by cecal ligation and puncture, and the outcome (n = 23 for hepcidin knockdown mice, n = 15 for controls) and pathogenic changes (n = 5) related to sepsis were evaluated. The impact of alteration of iron status on the survival rate of hepatic hepcidin knockdown mice (n = 18 to 19) was also investigated.

RESULTS

Disruption of liver hepcidin expression increased serum iron level (537.8 ± 28.1 μg/dl [mean ± SD] vs. 235.9 ± 62.2 μg/dl; P < 0.05) and reduced iron content in the spleen macrophages at the steady state. Hepatic hepcidin knockdown mice not only showed increased 7-day mortality (73.9% vs. 46.7%; P < 0.05), but also had exacerbated organ damage and oxidative stress, as well as compromised host inflammatory responses and bacterial clearance at 24 h after polymicrobial sepsis. Treating the hepatic hepcidin knockdown mice with low-iron diet plus iron chelation decreased systemic iron content (serum level: 324.0 ± 67.4 μg/dl vs. 517.4 ± 13.4 μg/dl; P < 0.05) and rescued the mice from lethal sepsis (7-day survival: 36.8% vs. 83.3%; P < 0.01).

CONCLUSIONS

Hepatic hepcidin plays an important role in sepsis through regulation of iron metabolism. The findings may have potential therapeutic implications for liver diseases in which hepcidin expression is decreased.

Baicalein protects against polymicrobial sepsis-induced liver injury via inhibition of inflammation and apoptosis in mice

Liver dysfunction has been known to occur frequently in cases of sepsis. Baicalein, the main active ingredient of the Scutellaria root, exerts anti-inflammatory and anti-apoptotic properties in endotoxic shock. However, the role of baicalein in polymicrobial sepsis-induced liver injury and its regulatory mechanisms remain unclear. In this study, we aimed to investigate the protective effects of baicalein on polymicrobial sepsis-induced liver injury and to explore the possible mechanisms. Polymicrobial sepsis was induced by cecal ligation and puncture (CLP) in C57BL/6 mice. Mice were treated with baicalein (100mg/kg, i.p) at 1h, 6h and 12h following CLP. Baicalein significantly improved the survival of septic mice. Treatment with baicalein ameliorated the CLP-induced liver injury, as indicated by the lower serum aminotransferase levels and the fewer histopathologic abnormalities. Baicalein reduced the neutrophil infiltration and the hepatic inflammatory cytokine expression and release. It also decreased the hepatic and the serum high-mobility group box 1 and macrophage migration inhibitory factor levels in septic mice. Moreover, baicalein significantly inhibited the mitogen-activated protein kinases (MAPKs) activation and suppressed the transcriptional activity of nuclear factor-kappa B (NF-κB). In conclusion, these results suggest that baicalein treatment could protect against the sepsis-induced liver injury, and improve the survival of mice with polymicrobial sepsis. The mechanism of the protective action of baicalein seems to involve its ability to reduce inflammatory response, to inhibit hepatic apoptosis, and to suppress MAPKs and NF-κB activation.

The role of the liver in sepsis

Despite the progress made in the clinical management of sepsis, sepsis morbidity and mortality rates remain high. The inflammatory pathogenesis and organ injury leading to death from sepsis are not fully understood for vital organs, especially the liver. Only recently has the role of the liver in sepsis begun to be revealed. Pre-existing liver dysfunction is a risk factor for the progression of infection to sepsis. Liver dysfunction after sepsis is an independent risk factor for multiple organ dysfunction and sepsis-induced death. The liver works as a lymphoid organ in response to sepsis. Acting as a double-edged sword in sepsis, the liver-mediated immune response is responsible for clearing bacteria and toxins but also causes inflammation, immunosuppression, and organ damage. Attenuating liver injury and restoring liver function lowers morbidity and mortality rates in patients with sepsis. This review summarizes the central role of liver in the host immune response to sepsis and in clinical outcomes.

Severe hemodynamic instability in a patient with suspected hepatoadrenal syndrome during liver transplantation -A case report-

Adrenal insufficiency, which is related to hemodynamic instability and increased mortality, has been reported in patients with advanced liver disease regardless of the presence of septic conditions. In this regard, the hepatoadrenal syndrome has been recently proposed as adrenal insufficiency in critically ill patients with liver disease. We describe here a 67-year-old female patient with hepatic failure and adrenal insufficiency. The patient showed stable vital signs and no evidence of sepsis preoperatively. Despite hydrocortisone replacement and inotropics administration, severe intraoperative hemodynamic instability was observed. Hydrocortisone administration was continued postoperatively, nevertheless inotropics could not be tapered. On postoperative day 11, the patient died due to pneumonia and septic shock. Hepatoadrenal syndrome may have played a key role in her severe hemodynamic fluctuation and poor outcome, reinforcing the importance of adrenal function in the liver transplantation surgery.

Kupffer cells potentiate liver sinusoidal endothelial cell injury in sepsis by ligating programmed cell death ligand-1

PD-1 and PD-L1 have been reported to provide peripheral tolerance by inhibiting TCR-mediated activation. We have reported that PD-L1-/- animals are protected from sepsis-induced mortality and immune suppression. Whereas studies indicate that LSECs normally express PD-L1, which is also thought to maintain local immune liver tolerance by ligating the receptor PD-1 on T lymphocytes, the role of PD-L1 in the septic liver remains unknown. Thus, we hypothesized initially that PD-L1 expression on LSECs protects them from sepsis-induced injury. We noted that the increased vascular permeability and pSTAT3 protein expression in whole liver from septic animals were attenuated in the absence of PD-L1. Isolated LSECs taken from septic animals, which exhibited increased cell death, declining cell numbers, reduced cellular proliferation, and VEGFR2 expression (an angiogenesis marker), also showed improved cell numbers, proliferation, and percent VEGFR2(+) levels in the absence of PD-L1. We also observed that sepsis induced an increase of liver F4/80(+)PD-1(+)-expressing KCs and increased PD-L1 expression on LSECs. Interestingly, PD-L1 expression levels on LSECs decreased when PD-1(+)-expressing KCs were depleted with clodronate liposomes. Contrary to our original hypothesis, we document here that increased interactions between PD-1(+) KCs and PD-L1(+) LSECs appear to lead to the decline of normal endothelial function-essential to sustain vascular integrity and prevent ALF. Importantly, we uncover an underappreciated pathological aspect of PD-1:PD-L1 ligation during inflammation that is independent of its normal, immune-suppressive activity.

Antimicrobial therapeutic determinants of outcomes from septic shock among patients with cirrhosis

It is unclear whether practice-related aspects of antimicrobial therapy contribute to the high mortality from septic shock among patients with cirrhosis. We examined the relationship between aspects of initial empiric antimicrobial therapy and mortality in patients with cirrhosis and septic shock. This was a nested cohort study within a large retrospective database of septic shock from 28 medical centers in Canada, the United States, and Saudi Arabia by the Cooperative Antimicrobial Therapy of Septic Shock Database Research Group between 1996 and 2008. We examined the impact of initial empiric antimicrobial therapeutic variables on the hospital mortality of patients with cirrhosis and septic shock. Among 635 patients with cirrhosis and septic shock, the hospital mortality was 75.6%. Inappropriate initial empiric antimicrobial therapy was administered in 155 (24.4%) patients. The median time to appropriate antimicrobial administration was 7.3 hours (interquartile range, 3.2-18.3 hours). The use of inappropriate initial antimicrobials was associated with increased mortality (adjusted odds ratio [aOR], 9.5; 95% confidence interval [CI], 4.3-20.7], as was the delay in appropriate antimicrobials (aOR for each 1 hour increase, 1.1; 95% CI, 1.1-1.2). Among patients with eligible bacterial septic shock, a single rather than two or more appropriate antimicrobials was used in 226 (72.9%) patients and was also associated with higher mortality (aOR, 1.8; 95% CI, 1.0-3.3). These findings were consistent across various clinically relevant subgroups.

CONCLUSION

In patients with cirrhosis and septic shock, inappropriate and delayed appropriate initial empiric antimicrobial therapy is associated with increased mortality. Monotherapy of bacterial septic shock is also associated with increased mortality. The process of selection and implementation of empiric antimicrobial therapy in this high-risk group should be restructured.

Combined therapy for acute hepatic failure

Acute hepatic failure (AHF) is a devastating clinical syndrome characterized by rapid impairment of liver functions and development of encephalopathy, multiple organ failure, and in most cases cerebral edema. AHF has a high mortality rate. Although advances in drug treatment, artificial liver and liver transplantation have significantly improved the prognosis of AHF, there is still a lack of effective treatment for AHF because of its complicated etiopathogenesis, rapid progression and less clinical knowledge about managing the disease. There is an urgent need to develop effective treatments for AHF. This article aims to review recent advances in the treatment of AHF.

Variceal bleeding: consensus meeting report from the Brazilian Society of Hepatology

In the last decades, several improvements in the management of variceal bleeding have resulted in a significant decrease in morbidity and mortality of patients with cirrhosis and bleeding varices. Progress in the multidisciplinary approach to these patients has led to a better management of this disease by critical care physicians, hepatologists, gastroenterologists, endoscopists, radiologists and surgeons. In this respect, the Brazilian Society of Hepatology has, recently, sponsored a consensus meeting in order to draw evidence-based recommendations on the management of these difficult-to-treat subjects. An organizing committee comprised of four people was elected by the Governing Board and was responsible to invite 27 researchers from distinct regions of the country to make a systematic review of the subject and to present topics related to variceal bleeding, including prevention, diagnosis, management and treatment, according to evidence-based medicine. After the meeting, all participants met together for discussion of the topics and the elaboration of the aforementioned recommendations. The organizing committee was responsible for writing the final document. The meeting was held at Salvador, May 6th, 2009 and the present manuscript is the summary of the systematic review that was presented during the meeting, organized in topics, followed by the recommendations of the Brazilian Society of Hepatology.