Clinical review: The liver in sepsis

FGF1 attenuates sepsis-induced coagulation dysfunction and hepatic injury via IL6/STAT3 pathway inhibition

BACKGROUND & AIMS

Sepsis, a globally prevalent and highly lethal condition, remains a critical medical challenge. This investigation aims to assess the relevance of FGF1 as a potential therapeutic target for sepsis.

METHODS

Sepsis was induced in C57BL/6 mice through LPS administration to establish an in vivo animal model. Various in vitro assays were conducted using human umbilical vein endothelial cells to elucidate the role of FGF1 in the disruption of the coagulation system and liver injury associated with sepsis, as well as to explore its underlying molecular mechanisms.

RESULTS

In in vivo experiments, FGF1 ameliorated coagulation system disruption in septic mice by reducing the levels of pro-inflammatory and coagulation-related factors in the bloodstream. FGF1 also enhanced liver function in septic mice, mitigating liver inflammation and cell apoptosis, fostering liver vascular regeneration, increasing liver blood perfusion, and improving mouse survival. In vitro experiments demonstrated that FGF1 could inhibit LPS-induced inflammatory responses and apoptosis in endothelial cells, fortify endothelial cell barrier function, decrease endothelial cell permeability, promote endothelial cell proliferation, and restore endothelial cell tube-forming ability. Both in vivo and in vitro experiments substantiated that FGF1 improved sepsis by inhibiting the IL-6/STAT3 signaling pathway.

CONCLUSION

In summary, our study indicates that FGF1 mitigates excessive inflammatory responses in sepsis by suppressing the IL-6/STAT3 signaling pathway, thereby improving systemic blood circulation and ameliorating liver damage in septic organisms. Consequently, this research identifies FGF1 as a potential clinical target for the treatment of human sepsis.

Clinical characteristics and prognosis of patients with early sepsis-related liver injury in Northeast China

Background: Sepsis-associated liver injury (SALI) occurs in about a third of septic patients, and it is often a poor prognostic factor. However, there are few studies on early SALI and its impact on the clinical course of sepsis. Here we explored the clinical characteristics, risk factors, and prognosis of early SALI. Methods: Two hundred and one patients with confirmed sepsis were divided into those with and without early SALI (on admission) based on liver function. The clinical characteristics and prognosis were compared between groups and associated factors identified by multivariable regression analysis. Results: Sepsis-related liver injury was present in 18.9% of septic patients on admission. High aspartate transaminase (AST), high direct bilirubin, and low plasma thromboplastin antecedent (PTA, factor XI) were risk factors for sepsis with SALI: the area under the AST curve was 0.825, corresponding to a sensitivity of 0.67 and a specificity of 0.93 (cutoff 91.6 U/L), the area under the direct bilirubin curve was 0.86, corresponding to a sensitivity of 0.83 and a specificity of 0.71 (cutoff 8.35 μmol/L), and the area under the PTA curve was 0.678, corresponding to a sensitivity of 0.47 and a specificity of 0.93 (cutoff 54.0). Conclusion: Septic patients with early SALI have early-onset coagulation disorders that must be recognized to instigate early intervention and halt sepsis progression. Elevated AST, PTA, and direct bilirubin may be independent risk markers of sepsis-related liver injury, and extra clinical vigilance is required when these factors are noted in patients with sepsis.

Inhibiting CD44-ICD Attenuates LPS-Induced Initiation of Hepatic Inflammation in Septic Mice

Sepsis is a severe condition induced by microbial infection. It elicits a systemic inflammatory response, leading to multi-organ failure, and the liver, as a scavenger, plays a significant role in this process. Controlling hepatic inflammation and maintaining liver function is crucial in managing sepsis. CD44-ICD, as a CD44 signal transductor, is involved in multiple inflammatory responses. However, the role of CD44-ICD in lipopolysaccharide (LPS)-induced hepatic inflammation has not been investigated. Therefore, we aimed to examine whether CD44-ICD initiates hepatic inflammation in septic mice. We induced hepatic inflammation in mice by administering LPS. DAPT, a CD44-ICD inhibitor, was given to mice or Chang cells 30 min or 1 h before LPS administration (10 mg/kg, i.p., or 100 ng/mL, respectively). Inhibition of CD44-ICD decreased the level of aspartate aminotransferase (AST), alanine aminotransferase (ALT), hepatic necrosis, inflammatory cell infiltration, interleukin (IL)-1β, inducible NO synthase (iNOS), nitric oxide (NO) production, nuclear factor (NF)κB signaling pathway proteins, and CD44 expression in mice. CD44-ICD inhibition also decreased IL-1β and CD44 expression levels in Chang cells. CD44-ICD may be a primary regulatory function in CD44-associated LPS-induced initiation of hepatic inflammation in mice.

A simple nomogram for predicting the mortality of PICU patients with sepsis-associated encephalopathy: a multicenter retrospective study

Background

As one of the serious complications of sepsis in children, sepsis-associated encephalopathy (SAE) is associated with significantly poor prognosis and increased mortality. However, predictors of outcomes for pediatric SAE patients have yet to be identified. The aim of this study was to develop nomograms to predict the 14-day and 90-day mortality of children with SAE, providing early warning to take effective measures to improve prognosis and reduce mortality.

Methods

In this multicenter, retrospective study, we screened 291 patients with SAE admitted to the PICU between January 2017 and September 2022 in Shandong Province. A least absolute shrinkage and selector operation (LASSO) method was used to identify the optimal prognostic factors predicting the outcomes in pediatric patients with SAE. Then, multivariable logistic regression analysis was performed based on these variables, and two nomograms were built for visualization. We used the area under the curve (AUC), calibration curves and decision curves to test the accuracy and discrimination of the nomograms in predicting outcomes.

Results

There were 129 patients with SAE in the training cohort, and there were 103 and 59 patients in the two independent validation cohorts, respectively. Vasopressor use, procalcitonin (PCT), lactate and pediatric critical illness score (PCIS) were independent predictive factors for 14-day mortality, and vasopressor use, PCT, lactate, PCIS and albumin were independent predictive factors for 90-day mortality. Based on the variables, we generated two nomograms for the early identification of 14-day mortality (AUC 0.853, 95% CI 0.787-0.919, sensitivity 72.4%, specificity 84.5%) and 90-day mortality (AUC 0.857, 95% CI 0.792-0.923, sensitivity 72.3%, specificity 90.6%), respectively. The calibration plots for nomograms showed excellent agreement of mortality probabilities between the observed and predicted values in both training and validation cohorts. Decision curve analyses (DCA) indicated that nomograms conferred high clinical net benefit.

Conclusion

The nomograms in this study revealed optimal prognostic factors for the mortality of pediatric patients with SAE, and individualized quantitative risk evaluation by the models would be practical for treatment management.

Carbon Dot-Loaded Apoptotic Vesicles Improve the Liver Kupffer Cell-Mediated Antibacterial Effect to Synergistically Alleviate Sepsis

Sepsis is a lethal systemic inflammatory disease against infection that lacks effective therapeutic approaches. Liver resident macrophage Kupffer cell (KC)-initiated bacterial clearance is crucial for the host to defend against infection. However, it remains unclear whether this process also governs the antibacterial therapy of sepsis that would be used to improve therapeutic outcomes. Here, we found that copper-doped carbon dots (Cu-CDs) exhibited superior antibacterial capabilities in vitro but displayed limited therapeutic effects in septic mice due to their limited ability to target the liver and restore KC antimicrobial capacity. Thus, we developed a composite nanodrug of copper-doped carbon dot-loaded apoVs (CC-apoVs) that combined the antibacterial ability of Cu-CDs and liver KC targeting features of apoV. Moreover, intravenous injection of CC-apoVs markedly alleviated the systemic infection and decreased the mortality of septic mice compared to Cu-CD and apoV infusion alone. Mechanistically, CC-apoV injection rescued impaired liver KCs during sepsis and enhanced their ability to capture and kill bloodborne bacteria. In addition, apoV-promoted macrophage killing of bacteria could be blocked by the inhibition of small GTPase Rab5. This study reveals a liver KC-targeted therapeutic strategy for sepsis and provides a nanodrug CC-apoV to improve the host antibacterial defense and amplify the therapeutic effect of the nanodrug.

Host and fungal factors both contribute to cryptococcosis-associated hyperammonemia (cryptammonia)

Cryptococcus neoformans and Cryptococcus gattii are both known urease producers and have the potential to cause hyperammonemia. We hypothesized that the risk of hyperammonemia is increased by renal failure, burden of cryptococcal infection, and fungal strain characteristics. We performed a retrospective review of plasma ammonia levels in patients with cryptococcal infections. Risk factors for hyperammonemia were statistically compared between patients with and without hyperammonemia (>53 µmol/L). Cryptococcal cells from three patients included in the study were recovered from our biorepository. Strain characteristics including urease activity, ammonia production, growth curves, microscopy, melanin production, and M13 molecular typing were analyzed and compared with a wild-type (WT) C. neoformans strain. We included 29 patients, of whom 37.9% had hyperammonemia, 59% had disseminated cryptococcal infection (DCI), and 41% had isolated central nervous system infection. Thirty-eight percent of patients had renal failure and 28% had liver disease. Renal failure was associated with 4.4 times (95% confidence interval [CI] 1.5, 13.0) higher risk of hyperammonemia. This risk was higher in DCIs (RR 6.2, 95% CI 1.0, 40.2) versus isolated cryptococcal meningitis (RR 2.5, 95% CI, 0.40, 16.0). Liver disease and cryptococcal titers were not associated with hyperammonemia. C. neoformans from one patient with extreme hyperammonemia demonstrated a 4- to 5-fold increase in extracellular urease activity, slow growth, enlarged cell size phenotypes, and diminished virulence factors. Hyperammonemia was strongly associated with renal failure in individuals with DCI, surpassing associations with liver failure or cryptococcal titers. However, profound hyperammonemia in one patient was attributable to high levels of urease secretion unique to that cryptococcal strain. Prospective studies are crucial to exploring the significance of this association.IMPORTANCECryptococcus produces and secretes the urease enzyme to facilitate its colonization of the host. Urease breaks down urea into ammonia, overwhelming the liver's detoxification process and leading to hyperammonemia in some hosts. This underrecognized complication exacerbates organ dysfunction alongside the infection. Our study investigated this intricate relationship, uncovering a strong association between the development of hyperammonemia and renal failure in patients with cryptococcal infections, particularly those with disseminated infections. We also explore mechanisms underlying increased urease activity, specifically in strains associated with extreme hyperammonemia. Our discoveries provide a foundation for advancing research into cryptococcal metabolism and identifying therapeutic targets to enhance patient outcomes.

Liensinine alleviates sepsis-induced acute liver injury by inhibiting the NF-κB and MAPK pathways in an Nrf2-dependent manner

Sepsis remains a serious public health issue that needs to be addressed globally. Severe liver injury caused by sepsis increases the risk of death in patients with sepsis. Liensinine (Lie) is one of the primary active components in Plumula nelumbinis and has anti-inflammatory and antioxidant effects. Nevertheless, the effects of Lie on septic liver injury are unclear. This research investigated the protective effect of Lie (10, 20 and 40 mg/kg) on liver damage via intraperitoneal administration of LPS (10 mg/kg) to C57BL/6 mice. Lie was given through intraperitoneal injection once a day for five days. Mice were treated with LPS intraperitoneally for 6 h at 1 h after Lie administration on the last day. The results suggested that Lie could decrease AST and ALT levels in serum, ameliorate histopathological changes and inhibit cell apoptosis in mice with LPS-induced septic liver injury. In addition, Lie inhibited increases in the mRNA levels of TNF-α, IL-1β, iNOS and IL-6. Lie also increased the mRNA level of IL-10. Lie reduced the content of MDA, a marker of lipid peroxidation, and increased the activity of the antioxidant enzymes GSH-Px, CAT and SOD. Our results also showed that Lie could suppress the LPS-activated MAPK and NF-κB pathways and trigger the Nrf2 signaling pathway both in vitro and in vivo. Additionally, an Nrf2 inhibitor (ML385) weakened the suppressive effect of Lie on the MAPK and NF-κB pathways. Our results demonstrated that the suppressive effect of Lie on the MAPK and NF-κB pathways was partially reliant on activation of the Nrf2 pathway. In summary, these results indicate that Lie can improve inflammation and oxidative stress by activating Nrf2, which is a prospective therapeutic drug for alleviating septic liver injury.

ACE2 Expressed on Myeloid Cells Alleviates Sepsis-Induced Acute Liver Injury via the Ang-(1-7)-Mas Receptor Axis

Sepsis-induced acute liver injury (ALI) is common in intensive care units. Angiotensin-converting enzyme 2 (ACE2) plays a vital role in hepatic fibrosis and steatosis; however, its role in sepsis-induced ALI remains unclear. This study found that hepatic ACE2 expression in cecal ligation and puncture (CLP)-treated mice significantly decreased 24 h after CLP. ACE2-transgenic (TG) mice exhibited a significant improvement in CLP-induced ALI, accompanied by the inhibition of hepatocyte apoptosis, oxidative stress, and inflammation, while ACE2-knockout mice demonstrated an opposite trend. During sepsis-induced ALI, ACE2-TG could also elevate the Ang-(1-7) and Mas receptor (MasR) levels in liver tissues. Interestingly, the MasR inhibitor A779 abrogated the favorable effects of ACE2 on CLP-induced ALI. In a bone marrow transplantation experiment, the ACE2-TG transplantation group showed significantly improved inflammation and liver dysfunction, less hepatocyte apoptosis, and reduced oxidative stress after CLP compared with the wild-type transplantation group. In contrast, the ACE2-knockout group showed poor inflammatory response and liver dysfunction, significantly more hepatocyte apoptosis, and elevated oxidative stress than the wild-type transplantation group after CLP. ACE2 protects against sepsis-induced ALI by inhibiting hepatocyte apoptosis, oxidative stress, and inflammation via the Ang-(1-7)-Mas receptor axis. Thus, targeting ACE2 may be a promising novel strategy for preventing and treating sepsis-induced ALI.

Unveiling the Role of Exosomes in the Pathophysiology of Sepsis: Insights into Organ Dysfunction and Potential Biomarkers

Extracellular vesicles (EVs) are tools for intercellular communication, mediating molecular transport processes. Emerging studies have revealed that EVs are significantly involved in immune processes, including sepsis. Sepsis, a dysregulated immune response to infection, triggers systemic inflammation and multi-organ dysfunction, posing a life-threatening condition. Although extensive research has been conducted on animals, the complex inflammatory mechanisms that cause sepsis-induced organ failure in humans are still not fully understood. Recent studies have focused on secreted exosomes, which are small extracellular vesicles from various body cells, and have shed light on their involvement in the pathophysiology of sepsis. During sepsis, exosomes undergo changes in content, concentration, and function, which significantly affect the metabolism of endothelia, cardiovascular functions, and coagulation. Investigating the role of exosome content in the pathogenesis of sepsis shows promise for understanding the molecular basis of human sepsis. This review explores the contributions of activated immune cells and diverse body cells' secreted exosomes to vital organ dysfunction in sepsis, providing insights into potential molecular biomarkers for predicting organ failure in septic shock.

Design, Synthesis, and Biological Evaluation of a Novel NIK Inhibitor with Anti-Inflammatory and Hepatoprotective Effects for Sepsis Treatment

NIK plays a crucial role in the noncanonical NF-κB signaling pathway associated with diverse inflammatory and autoimmune diseases. Our study presents compound 54, a novel NIK inhibitor, designed through a structure-based scaffold-hopping approach from the previously identified B022. Compound 54 demonstrates remarkable selectivity and potency against NIK both in vitro and in vivo, effectively suppressing pro-inflammatory cytokines and nitric oxide production. In mouse models, compound 54 protected against LPS-induced systemic sepsis, reducing AST, ALT, and AKP liver injury markers. Additionally, it also attenuates sepsis-induced lung and kidney damage. Mechanistically, compound 54 blocks the noncanonical NF-κB signaling pathway by targeting NIK, preventing p100 to p52 processing. This work reveals a novel class of NIK inhibitors with significant potential for sepsis therapy.

Mitochondrial Diabetes Mellitus With Mitochondrial DNA 3316G>A Mutation: A Unique Autopsy Case Presenting With Sepsis-Associated Cholestasis

A 70-year-old female, diagnosed with mitochondrial diabetes mellitus (MDM) showing previously a point mutation at mitochondrial DNA 3316G>A, noticed urinary tract infection and diabetic gangrene of the foot with Gram-negative Bacteroides fragilis bacteremia, followed by aggressive jaundice with high serum level of direct bilirubin. She died two months after the symptom onset. At autopsy, multiple foci of bacteremia-induced hemorrhagic infarction were observed in the congestive bilateral lungs, whereas the cholestatic liver revealed no overt gross cholangiectasis. Microscopic findings characteristically showed many bile thrombi in the biliary canaliculi of hepatic lobules without any evidence of severe shock liver. Finally, we diagnosed it exclusively as sepsis-associated cholestasis due to the marked elevation of Gram-negative bacteria-derived endotoxins and inflammatory cytokines. We propose that these unique liver features in our MDM case might be one of the new clues to unveil its enigmatic etiology.

Combined metabolomic and proteomic analysis of sepsis related acute liver injury and its pathogenesis research

BACKGROUND

Sepsis-induced acute liver injury is common in patients in intensive care units. However, the exact mechanism of this condition remains unclear. The purpose of this study was to investigate the roles and mechanisms of proteins and metabolites in the liver tissue of mice after sepsis and elucidate the molecular biological mechanisms of sepsis-related liver injury.

METHODS

First, a lipopolysaccharide (LPS)-induced sepsis mouse model was established. Then, according to alanine aminotransferase (ALT) and aspartate aminotransferase (AST) detection in mouse serum and liver histopathological examination (HE) staining, the septic mice were divided into two groups: acute liver injury after sepsis and nonacute liver injury after sepsis. Metabolomics and proteomic analyses were performed on the liver tissues of the two groups of mice to identify significantly different metabolites and proteins. The metabolomics and proteomics results were further analysed to identify the biological indicators and pathogenesis related to the occurrence and development of sepsis-related acute liver injury at the protein and metabolite levels.

RESULTS

A total of 14 differentially expressed proteins and 46 differentially expressed metabolites were identified. Recombinant Erythrocyte Membrane Protein Band 4.2 (Epb42) and adenosine diphosphate (ADP) may be the key proteins and metabolites responsible for sepsis-related acute liver injury, according to the correlation analysis of proteomics and metabolomics. The expression of the differential protein Epb42 was further verified by western blot (WB) detection.

CONCLUSIONS

Our study suggests that the differential protein Epb42 may be key proteins causing sepsis-associated acute liver injury, providing new and valuable information on the possible mechanism of sepsis-associated acute liver injury.

Sepsis, Management & Advances in Metabolomics

Though there have been developments in clinical care and management, early and accurate diagnosis and risk stratification are still bottlenecks in septic shock patients. Since septic shock is multifactorial with patient-specific underlying co-morbid conditions, early assessment of sepsis becomes challenging due to variable symptoms and clinical manifestations. Moreover, the treatment strategies are traditionally based on their progression and corresponding clinical symptoms, not personalized. The complex pathophysiology assures that a single biomarker cannot identify, stratify, and describe patients affected by septic shock. Traditional biomarkers like CRP, PCT, and cytokines are not sensitive and specific enough to be used entirely for a patient's diagnosis and prognosis. Thus, the need of the hour is a sensitive and specific biomarker after comprehensive analysis that may facilitate an early diagnosis, prognosis, and drug development. Integration of clinical data with metabolomics would provide means to understand the patient's condition, stratify patients better, and predict the clinical outcome.

The Prognostic Value of a Liver Function Test Using Indocyanine Green (ICG) Clearance in Patients with Multiple Organ Dysfunction Syndrome (MODS)

BACKGROUND

Multiple organ dysfunction syndrome (MODS) is common in intensive care units (ICUs) and is associated with high mortality. Although there have been multiple investigations into a multitude of organ dysfunctions, little is known about the role of liver dysfunction. In addition, clinical and laboratory findings of liver dysfunction may occur with a significant delay. Therefore, the aim of this study was to investigate whether a liver function test, based on indocyanine green (ICG)-clearance, contains prognostic information for patients in the early phase of MODS.

METHODS

The data of this analysis were based on the MODIFY study, which included 70 critically ill patients of a tertiary medical ICU in the early phase of MODS (≤24 h after diagnosis by an APACHE II score ≥ 20 and a sinus rhythm ≥ 90 beats per minute, with the following subgroups: cardiogenic (cMODS) and septic MODS (sMODS)) over a period of 18 months. ICG clearance was characterized by plasma disappearance rate = PDR (%/min); it was measured non-invasively by using the LiMON system (PULSION Medical Systems, Feldkirchen, Germany). The PDR was determined on the day of study inclusion (baseline) and after 96 h. The primary endpoint of this analysis was 28-day mortality.

RESULTS

ICG clearance was measured in 44 patients of the MODIFY trial cohort, of which 9 patients had cMODS (20%) and 35 patients had sMODS (80%). Mean age: 59.7 ± 16.5 years; 31 patients were men; mean APACHE II score: 33.6 ± 6.3; 28-day mortality was 47.7%. Liver function was reduced in the total cohort as measured by a PDR of 13.4 ± 6.3%/min At baseline, there were no relevant differences between survivors and non-survivors regarding ICG clearance (PDR: 14.6 ± 6.1%/min vs. 12.1 ± 6.5%/min; p = 0.21). However, survivors showed better liver function than non-survivors after 96 h (PDR: 21.9 ± 6.3%/min vs. 9.2 ± 6.3%/min, p < 0.05). Consistent with these findings, survivors but not non-survivors show a significant improvement in the PDR (7.3 ± 6.3%/min vs. -2.9 ± 2.6%/min; p < 0.01) within 96 h. In accordance, receiver-operating characteristic curves (ROCs) at 96 h but not at baseline show a link between the PDR and 28-day mortality (PDR at 96 h: AUC: 0.87, 95% CI: 0.76-0.98; p < 0.01.

CONCLUSIONS

In our study, we found that ICG clearance at baseline did not provide prognostic information in patients in the early stages of MODS despite being reduced in the total cohort. However, improvement of ICG clearance 96 h after ICU admission is associated with reduced 28-day mortality.

Intragastric infusion of a liquid diet with low-methoxyl pectin alleviates fecal inconsistency and local proinflammatory cytokine expression in lipopolysaccharide-septic rats

OBJECTIVE

Diarrhea interrupts enteral nutrition management in hospitalized patients with severe illnesses, such as sepsis. Pectin, a water-soluble dietary fiber, has the potential to maintain intestinal function and may reduce inflammatory reactions. The aim of this study was to demonstrate that the addition of low-methoxyl (LM) pectin to a liquid diet suppresses softening of stool texture and reduces tissue inflammatory responses in enteral nutrition management during sepsis.

METHODS

A fat-enriched liquid diet with LM pectin (P-EN) or a liquid diet without dietary fiber (FF-EN) was given continuously to rats through a gastric catheter. Lipopolysaccharide (LPS; 10 mg/kg) was injected intraperitoneally 24 h (study 1) and 7 h (study 2) before sacrifice.

RESULTS

LPS injection significantly worsened fecal property scores in rats infused with FF-EN compared with the rats given P-EN in study 1. Whereas many myeloperoxidase-positive cells infiltrated the liver, and the hepatic expressions of chemokine genes were markedly elevated 24 h after LPS administration, these findings were clearly alleviated in the LM pectin-containing liquid diet group. In study 2, protein expressions of proinflammatory cytokines, such as small intestinal tumor necrosis factor-α and hepatic interleukin-1β, and interleukin-6, were significantly downregulated in the P-EN LPS group compared with the FF-EN LPS group.

CONCLUSIONS

A liquid diet containing LM pectin allows enteral nutrition management with a low risk for diarrhea and reduces local inflammation under septic conditions.

Organ support in sepsis: A panoramic view from infection to death

Despite significant advancements in medical research, sepsis persists as a leading cause of mortality in intensive care units (ICUs). Sepsis intricately contributes to organ failure, amplifying both morbidity and mortality. In these instances, a comprehensive comprehension of the physiology of each organ is imperative for accurate diagnosis and effective management. Within the context of an ICU clinical scenario, a meticulous evaluation and monitoring of six pivotal organ systems cardiovascular, renal, respiratory, neurological, hematological, and hepatic are essential. The primary objective in managing sepsis-induced organ failure is the early detection and intervention, encompassing timely administration of antibiotics, identification and control of the infection source, and implementation of supportive therapy. Despite the extensive body of medical literature, there is a conspicuous absence of evidence-based multi-organ management strategies for such patients. The intricate interplay between organs, commonly referred to as organ crosstalk, presents a formidable challenge in navigating the complexities of sepsis management.

(E)-2-methoxy-4-(3-(4-methoxyphenyl)prop-1-en-1-yl)phenol alleviates inflammatory responses in LPS-induced mice liver sepsis through inhibition of STAT3 phosphorylation

Sepsis is a life-threatening disease with limited treatment options, and the inflammatory process represents an important factor affecting its progression. Many studies have demonstrated the critical roles of signal transducer and activator of transcription 3 (STAT3) in sepsis pathophysiology and pro-inflammatory responses. Inhibition of STAT3 activity may therefore represent a promising treatment option for sepsis. We here used a mouse model to demonstrate that (E)-2-methoxy-4-(3-(4-methoxyphenyl)prop-1-en-1-yl)phenol (MMPP) treatment prevented the liver sepsis-related mortality induced by 30 mg/kg lipopolysaccharide (LPS) treatment and reduced LPS-induced increase in alanine transaminase, aspartate transaminase, and lactate dehydrogenase levels, all of which are markers of liver sepsis progression. These recovery effects were associated with decreased LPS-induced STAT3, p65, and JAK1 phosphorylation and proinflammatory cytokine (interleukin 1 beta, interleukin 6, and tumor necrosis factor alpha) level; expression of cyclooxygenase-2 and induced nitric oxide synthase were also reduced by MMPP. In an in vitro study using the normal liver cell line THLE-2, MMPP treatment prevented the LPS-induced increase of STAT3, p65, and JAK1 phosphorylation and inflammatory protein expression in a dose-dependent manner, and this effect was enhanced by combination treatment with MMPP and STAT3 inhibitor. The results clearly indicate that MMPP treatment prevents LPS-induced mortality by inhibiting the inflammatory response via STAT3 activity inhibition. Thus, MMPP represents a novel agent for alleviating LPS-induced liver sepsis.

Management of liver disease and portal hypertension in common variable immunodeficiency (CVID)

Patients with common variable immunodeficiency (CVID) frequently develop liver disease and associated complications, which represent an increasingly prevalent unmet medical need. The main hepatic manifestation of CVID is nodular regenerative hyperplasia (NRH), resulting in non-cirrhotic portal hypertension (NCPH). Liver disease is often underdiagnosed, leading to poor outcomes and decreased survival. The increasing numbers of patients with CVID who are diagnosed late with progressive liver disease underscores the importance of appropriate clinical management and treatment of liver complications. At the same time, specific guidelines for the clinical management of CVID-related liver disease are still lacking. Here, we review the epidemiology of CVID-related liver disease, reveal new insights into NRH and NCPH biology and highlight recently uncovered opportunities for NCPH diagnostics in CVID. Finally, we focus on current management of liver disease, portal hypertension and its complications - the key challenge in patients with CVID. Specifically, we review recent data regarding the role of transjugular intrahepatic portosystemic shunt and liver transplantation in clinical management. The role for anticoagulants and immunosuppressants targeting the pathogenesis of NRH will also be discussed. We propose an updated algorithm for the diagnostic work-up and treatment of NCPH in CVID. Finally, we consider future needs and therapeutic opportunities for CVID-related liver disease.

Fibrinogen-to-Albumin Ratio in Neonatal Sepsis

Background

Previous studies have established an association between fibrinogen-to-albumin ratio (FAR) and cancer, cardiovascular disease, and coronavirus disease 2019. However, no studies have investigated the relationship between FAR and neonatal sepsis. This study aims to evaluate the association of fibrinogen-to-albumin ratio with the presence and severity of sepsis in neonates.

Methods

A total of 1292 neonates with suspected sepsis were enrolled in this study. Clinical and laboratory data were collected from electronic medical records. Neonates with final diagnosis with sepsis were divided into the sepsis group, The remaining neonates were divided into the control group. Neonates with sepsis were further categorized into mild (n = 312) and severe (n = 425) groups based on the severity of their condition. FAR was determined by dividing the plasma fibrinogen concentration (g/L) by the serum albumin concentration (g/L). The statistical analyses were conducted using the SPSS 26.0 statistical software package, as deemed appropriate.

Results

FAR levels were significantly higher in neonates with sepsis compared to the control group. Additionally, a significant gradual increase in FAR was observed in the control, mild sepsis, and severe sepsis groups (P < 0.001). Correlation analysis showed that FAR had a positive correlation with PCT, CRP, and the length of hospital stay. Multiple logistic regression analysis showed that FAR was independently associated with the presence and severity of neonatal sepsis. Specifically, FAR was identified as an independent risk factor for both the presence of sepsis (OR = 8.641, 95% CI 5.708-13.080, P < 0.001) and severe sepsis (OR = 2.817, 95% CI 1.701-4.666, P < 0.001).

Conclusion

FAR is significantly increased in neonates with sepsis and had a correlation with the severity of sepsis. Increased FAR was an independent predictor for the presence and severity of neonatal sepsis.

Incidence of hypoxic hepatitis in patients with cardiogenic shock and association with mortality

AIMS

Shock of any cause leads to end-organ damage due to ischaemia, especially in perfusion-sensitive organs such as the liver. In septic shock, hypoxic hepatitis (S-HH) is defined as the 20-fold increase of the upper normal limit of aspartate aminotransferase (ASAT) and alanine aminotransferase (ALAT) and is associated with a mortality of up to 60%. However, as pathophysiology, dynamics, and treatment differ between septic and cardiogenic shock (CS), the S-HH definition may not be suitable for CS. Therefore, we aim to evaluate if the S-HH definition is applicable in CS patients.

METHODS AND RESULTS

This analysis was based on a registry of all-comer CS patients treated between 2009 and 2019 at a tertiary care centre with exclusion of minors and patients without all necessary ASAT and ALAT values. N = 698. During in-hospital follow-up, 386 (55.3%) patients died. The S-HH was not significantly associated with in-hospital mortality in CS patients. To define HH among patients with CS (C-HH), optimal cut-off values were found to be ≥1.34-fold increase for ASAT and ≥1.51-fold increase for ALAT in serial measurements. The incidence of C-HH was 254/698 patients (36%) and C-HH showed a strong association with in-hospital mortality (odds ratio 2.36, 95% confidence interval: 1.61, 3.49).

CONCLUSION

The C-HH is a frequent and relevant comorbidity in patients with CS, although its definition varies from the established definition of HH in patients with septic shock. As C-HH contributed to excess mortality risk, these findings emphasize the need for further investigation of therapies reducing the occurrence of C-HH and also improving the associated outcome.

Effect of cogon grass root ethanol extract on fatty acid binding protein 4 and oxidative stress markers in a sepsis mouse model

Background: Sepsis causes several immunological and metabolic alterations that induce oxidative stress. The modulation of fatty acid-binding protein 4 (FABP4) has been shown to worsen this condition. Extract of cogon grass root (ECGR) contains flavonoids and isoeugenol compounds that exhibit anti-inflammatory and antioxidant properties. This study aimed to assess the effects of ECGR on FABP4 and oxidative stress-related factors in a sepsis mouse model. Methods: Twenty-nine male mice ( Mus musculus) of the Deutsche Denken Yoken strain were divided into four groups: group 1, control; group 2, mice treated with 10 μL/kg body weight (BW) lipopolysaccharide (LPS); and groups 3 and 4, mice pre-treated with 90 and 115 mg/kg BW, respectively, and then treated with 10 μL/kg BW LPS for 14 d. Blood, liver, lymph, and cardiac tissue samples were collected and subjected to histological and complete blood examinations. Antioxidant (Glutathione peroxidase 3 (GPx3) and superoxide dismutase), FABP4 levels, and immune system-associated biomarker levels (TNF-α, IL-6 and IL-1β) were measured. Results: Significant increases in platelet levels (p = 0.03), cardiomyocyte counts (p =0.004), and hepatocyte counts (p = 0.0004) were observed in group 4 compared with those in group 2. Conversely, compared with those in group 2, there were significant decreases in TNF-α expression in group 3 (p = 0.004), white pulp length and width in group 4 (p = 0.001), FABP4 levels in groups 3 and 4 (p = 0.015 and p = 0.012, respectively), lymphocyte counts in group 4 (p = 0.009), and monocyte counts (p = 0.000) and polymorphonuclear cell counts in the livers (p = 0.000) and hearts (p = 0.000) of groups 3 and 4. Gpx3 activity was significantly higher in group 3 than in group 1 (p = 0.04). Conclusions: ECGR reduces FABP4 level and modulating oxidative stress markers in sepsis mouse model.

Prognostic Value of the AST/ALT Ratio versus Bilirubin in Patients with Cardiogenic Shock

This study investigates the prognostic value of the aspartate-to-alanine aminotransferase ratio (i.e., AST/ALT ratio) and bilirubin in patients with cardiogenic shock (CS). Despite ongoing improvements regarding the treatment of CS patients, invasive care unit (ICU) mortality in CS patients remains unacceptably high. Limited data regarding the prognostic value of the AST/ALT ratio and bilirubin in patients suffering from CS is available. The authors hypothesize the measurement of liver enzymes during the course of CS may be an easy and feasible method to assess right-heart dysfunction and prognosis in patients with CS. Consecutive patients with CS from 2019 to 2021 were included. Blood samples were retrieved from the day of disease onset (day 1), days 2, 3, 4 and 8. The prognostic value of the AST/ALT ratio and bilirubin was tested for 30-day all-cause mortality. Statistical analyses included univariable t-tests, Spearman's correlations, Kaplan-Meier analyses, as well as multivariable Cox proportional regression analyses. A total of 157 CS patients were included, with an overall rate of all-cause mortality at 30 days of 51%. The median AST/ALT ratio on day 1 was 1.4, and the median bilirubin was 0.63 mg/dL. No association of the baseline AST/ALT ratio (HR = 1.005; 95% CI 0.649-1.558; p = 0.981) and bilirubin (HR = 1.320; 95% CI 0.834-2.090; p = 0.236) with the risk of 30-day all-cause mortality was found. In contrast, the AST/ALT ratio on day 4 was associated with the risk of 30-day all-cause mortality (HR = 2.826; 95% CI 1.227-6.510; p = 0.015), which was still evident after the multivariable adjustment (HR = 2.830; 95% CI 1.054-7.690; p = 0.039). The AST/ALT ratio during the course of ICU hospitalization from day 4-but not the baseline AST/ALT ratio and bilirubin-was associated with an increased risk of 30-day all-cause mortality in CS patients.

Mesenchymal stem cell-derived exosome alleviates sepsis- associated acute liver injury by suppressing MALAT1 through microRNA-26a-5p: an innovative immunopharmacological intervention and therapeutic approach for sepsis

Background

Sepsis is a syndrome with the disturbed host response to severe infection and is a major health problem worldwide. As the front line of infection defense and drug metabolism, the liver is vulnerable to infection- or drug-induced injury. Acute liver injury (ALI) is thus common in patients with sepsis and is significantly associated with poor prognosis. However, there are still few targeted drugs for the treatment of this syndrome in clinics. Recent studies have reported that mesenchymal stem cells (MSCs) show potential for the treatment of various diseases, while the molecular mechanisms remain incompletely characterized.

Aims and Methods

Herein, we used cecal ligation puncture (CLP) and lipopolysaccharide (LPS) plus D-galactosamine (D-gal) as sepsis-induced ALI models to investigate the roles and mechanisms of mesenchymal stem cells (MSCs) in the treatment of ALI in sepsis.

Results

We found that either MSCs or MSC-derived exosome significantly attenuated ALI and consequent death in sepsis. miR-26a-5p, a microRNA downregulated in septic mice, was replenished by MSC-derived exosome. Replenishment of miR-26a-5p protected against hepatocyte death and liver injury caused by sepsis through targeting Metastasis Associated Lung Adenocarcinoma Transcript 1 (MALAT1), a long non-coding RNA highly presented in hepatocyte and liver under sepsis and inhibiting anti-oxidant system.

Conclusion

Taken together, the results of the current study revealed the beneficial effects of MSC, exosome or miR-26a-5p on ALI, and determined the potential mechanisms of ALI induced by sepsis. MALAT1 would be a novel target for drug development in the treatment of this syndrome.

Fibronectin extra domain a limits liver dysfunction and protects mice during acute inflammation

Background and aim

The primary transcript of fibronectin (FN) undergoes alternative splicing to generate different isoforms, including FN containing the Extra Domain A (FN_EDA+), whose expression is regulated spatially and temporarily during developmental and disease conditions including acute inflammation. The role of FN_EDA+ during sepsis, however, remains elusive.

Methods

Mice constitutively express the EDA domain of fibronectin (EDA^+/+); lacking the FN EDA domain (EDA^-/-) or with a conditional ablation of EDA + inclusion only in liver produced FN (alb-CRE⁺EDA floxed mice) thus expressing normal plasma FN were used. Systemic inflammation and sepsis were induced by either LPS injection (70 mg/kg) or by cecal ligation and puncture (CLP) Neutrophils isolated from septic patients were tested for neutrophil binding ability.

Results

We observed that EDA^+/+ were protected toward sepsis as compared to EDA^-/- mice. Also alb-CRE⁺EDA floxed mice presented reduced survival, thus indicating a key role for EDA in protecting toward sepsis. This phenotype was associated with improved liver and spleen inflammatory profile. Ex vivo experiments showed that neutrophils bind to a larger extent to an FN_EDA + coated surface as compared to FN, thus potentially limiting their over-reactivity.

Conclusions

Our study demonstrates that the inclusion of the EDA domain in fibronectin dampens the nflammatoryi consequences of sepsis.

Hyperbilirubinemia in a Patient With Sepsis: A Diagnostic Challenge

Cholestasis due to sepsis is commonly seen in critically ill patients; however, it is often overlooked and poses a challenge in clinical diagnosis and management. In this report, we present a 29-year-old woman who presented to the emergency department with jaundice and symptoms of a urinary tract infection. Initially suspected to be Dubin-Johnson syndrome, sepsis-induced cholestasis was eventually diagnosed after testing. Sepsis should always be considered as part of the differential diagnosis while managing a patient with jaundice. The management of sepsis-induced cholestasis involves treating the underlying infection. In most cases, liver injury improves with the resolution of the infectious process.

The combination of mesenchymal stem cell- and hepatocyte-derived exosomes, along with imipenem, ameliorates inflammatory responses and liver damage in a sepsis mouse model

Aim Sepsis is a medical emergency with no definitive treatment. Animal experiments have confirmed the therapeutic characteristics of exosomes in reducing inflammation and tissue damage. The study investigates the effect of MSC and hepatocyte-derived exosomes along with imipenem in controlling systemic and local (liver) inflammation in a mouse model of sepsis.

MAIN METHODS

To induce sepsis in C57BL/6 mice, the Cecal Ligation and Puncture (CLP) model was used. The mice were given various treatments, including imipenem, MSC-derived exosomes, hepatocyte-derived exosomes, and a mixture of exosomes. Blood and liver samples were collected and analyzed for cell blood count, liver enzymes, NO levels, cytokine concentrations, and bacterial presence. The percentages of TCD3 + CD4+/CD8+ and Treg in the spleen and mesenteric lymph nodes were also assessed using flow cytometry. The pathological changes were assessed in the liver, lung, and heart tissues. In addition, the cytokine content of exosomes was measured by ELISA.

KEY FINDINGS

Our results demonstrated that MSC-derived exosomes+imipenem could control systemic and local inflammation and increase the TCD4+ and Treg populations. Hepatocyte-derived exosomes+imipenem reduced inflammation in the liver and increased the TCD8+ and Treg populations. The mixture of exosomes+imipenem had the best function in reducing inflammation, maintaining all T lymphocyte populations, reducing liver damage, and ultimately increasing the survival rate.

SIGNIFICANCE

The mixture of exosomes derived from MSCs and hepatocytes, along with imipenem, in the inflammatory phase of sepsis could be a promising therapeutic strategy in sepsis treatment.

Diagnostic and Prognostic Performance of Plasma Albumin and Cholinesterase in Patients with Sepsis and Septic Shock

OBJECTIVE

Despite improved risk stratification tools and identification of novel biomarkers for the diagnosis and prognosis in patients with sepsis, sepsis-related mortality has not significantly improved during the past years. This study investigates the diagnostic and prognostic role of the plasma albumin and cholinesterase (ChE) in patients with sepsis and septic shock.

METHODS

Consecutive patients with sepsis and septic shock from 2019 to 2021 were included at one institution. Blood samples were obtained on the day of disease onset (day 1), and on days 2, 3, 5, and 7 thereafter. The diagnostic value of ChE for the diagnosis of a septic shock was compared to albumin and the prognostic value of the albumin and the ChE for 30-day all-cause mortality was tested.

RESULTS

239 patients were included with a median albumin level of 21.4 g/dL and a median ChE of 5004 U/L on admission. With an area under the curve (AUC) of 0.641-0.762 on days 3 and 5, the ChE was associated with moderate but better diagnostic discrimination between sepsis and septic shock than albumin. Furthermore, ChE was able to discriminate between 30-day non-survivors and survivors (range of AUC 0.612-0.686). Patients with a ChE below the median had higher rates of 30-days all-cause mortality in comparison to patients with a ChE above the median (65 vs. 42%, log rank p = 0.001; HR = 1.820; 95% CI = 1.273-2.601; p = 0.001), which was still demonstrated after multivariable adjustment.

CONCLUSION

The level of ChE was associated with moderate diagnostic and prognostic accuracy in patients with sepsis and septic shock, whereas albumin was not.

Effect of preoperative liver-directed therapy prior to hepatic resection

INTRODUCTION

Hepatobiliary malignancies present with advanced disease precluding upfront resection. Liver-directed therapy (LDT), particularly Y-90 radioembolization and transarterial chemoembolization (TACE), has become increasingly utilized to facilitate attempt at oncologic resection. However, the safety profile of preoperative LDT is limited.

METHODS

Retrospective review of the ACS NSQIP main and targeted hepatectomy registries for 2014-2016. Primary objective was evaluation of outcomes between preoperative LDT cases and those that received upfront resection.

RESULTS

A total of 8923 cases met selection criteria. 192 cases (2.15%) received either Y-90 or TACE prior to hepatectomy. Multivariate analysis for all study patients revealed preoperative LDT significantly increased the risk of perioperative transfusion (OR 2.19, 95% CI 1.445-3.328, P < 0.0001), sepsis (OR 2.21, 95% CI 1.104-4.411, P = 0.022), and liver failure (OR 2.72, 95% CI 1.562-4.747, P < 0.0001). Subgroup analysis found for primary hepatobiliary malignancies LDT only increased the risk for liver failure. While for secondary hepatic tumors LDT significantly increased perioperative transfusion, sepsis, cardiac failure, renal failure, liver failure, and mortality. The complication profile also significantly increased with advanced T stage. Conversely, on propensity score matching preoperative LDT did not significantly increase perioperative complications.

CONCLUSION

Preoperative LDT has the potential to convert inoperable hepatic tumors into resectable disease but there is a general increased risk for significant postoperative complications, most notable liver failure. However, on controlled analysis preoperative LDT does not increase perioperative complications and should not be considered a contraindication to resection.

Diagnostic and prognostic value of the AST/ALT ratio in patients with sepsis and septic shock

OBJECTIVE

The study investigates the diagnostic and prognostic value of the aspartate aminotransferase (AST) to alanine aminotransferase (ALT) ratio in patients with sepsis and septic shock. Limited data regarding the prognostic value of the AST/ALT ratio in patients suffering from sepsis or septic shock is available.

METHODS

Consecutive patients with sepsis and septic shock from 2019 to 2021 were included monocentrically. Blood samples were retrieved from day of disease onset (day 1), day 2, 3, 5 and 7. First, the diagnostic value of the AST/ALT ratio was tested for septic shock compared to sepsis. Second, the prognostic value of the AST/ALT ratio was tested for 30-d all-cause mortality. Statistical analyses included univariable t-test, Spearman's correlation, C-statistics, Kaplan-Meier analyses, as well as multivariable mixed analysis of variance (ANOVA), Cox proportional regression analyses and propensity score matching.

RESULTS

A total of 289 patients were included, of which 55% had sepsis and 45% septic shock. The overall rate of all-cause mortality at 30 d was 53%. With an area under the curve (AUC) of 0.651 on day 1 and 0.794 on day 7, the AST/ALT ratio revealed moderate but better diagnostic discrimination of septic shock compared to bilirubin. Furthermore, the AST/ALT ratio was able to discriminate 30-d all-cause mortality (AUC = 0.624; 95% CI 0.559 - 0.689; p = 0.001). Patients with an AST/ALT ratio above the median (>1.8) had higher rates of 30-d all-cause mortality compared to lower values (mortality rate 63 vs. 43%; log-rank p = 0.001), even after multivariable adjustment (HR = 1.703; 95% CI 1.182 - 2.453; p = 0.004) and propensity score matching.

CONCLUSIONS

The AST/ALT was a reliable diagnostic tool for the diagnosis of septic shock as well as a reliable tool to predict 30-d all-cause mortality in patients suffering from sepsis and septic shock.

Mortality rates of severe COVID-19-related respiratory failure with and without extracorporeal membrane oxygenation in the Middle Ruhr Region of Germany

The use of extracorporeal membrane oxygenation (ECMO) is discussed to improve patients' outcome in severe COVID-19 with respiratory failure, but data on ECMO remains controversial. The aim of the study was to determine the characteristics of patients under invasive mechanical ventilation (IMV) with or without veno-venous ECMO support and to evaluate outcome parameters. Ventilated patients with COVID-19 with and without additional ECMO support were analyzed in a retrospective multicenter study regarding clinical characteristics, respiratory and laboratory parameters in day-to-day follow-up. Recruitment of patients was conducted during the first three COVID-19 waves at four German university hospitals of the Ruhr University Bochum, located in the Middle Ruhr Region. From March 1, 2020 to August 31, 2021, the charts of 149 patients who were ventilated for COVID-19 infection, were included (63.8% male, median age 67 years). Fifty patients (33.6%) received additional ECMO support. On average, ECMO therapy was initiated 15.6 ± 9.4 days after symptom onset, 10.6 ± 7.1 days after hospital admission, and 4.8 ± 6.4 days after the start of IMV. Male sex and higher SOFA and RESP scores were observed significantly more often in the high-volume ECMO center. Pre-medication with antidepressants was more often detected in survivors (22.0% vs. 6.5%; p = 0.006). ECMO patients were 14 years younger and presented a lower rate of concomitant cardiovascular diseases (18.0% vs. 47.5%; p = 0.0004). Additionally, cytokine-adsorption (46.0% vs. 13.1%; p < 0.0001) and renal replacement therapy (76.0% vs. 43.4%; p = 0.0001) were carried out more frequently; in ECMO patients thrombocytes were transfused 12-fold more often related to more than fourfold higher bleeding complications. Undulating C-reactive protein (CRP) and massive increase in bilirubin levels (at terminal stage) could be observed in deceased ECMO patients. In-hospital mortality was high (Overall: 72.5%, ECMO: 80.0%, ns). Regardless of ECMO therapy half of the study population deceased within 30 days after hospital admission. Despite being younger and with less comorbidities ECMO therapy did not improve survival in severely ill COVID-19 patients. Undulating CRP levels, a massive increase of bilirubin level and a high use of cytokine-adsorption were associated with worse outcomes. In conclusion, ECMO support might be helpful in selected severe cases of COVID-19.

Long Noncoding RNA U90926 Is Induced in Activated Macrophages, Is Protective in Endotoxic Shock, and Encodes a Novel Secreted Protein

Thousands of long noncoding RNAs are encoded in mammalian genomes, yet most remain uncharacterized. In this study, we functionally characterized a mouse long noncoding RNA named U90926. Analysis of U90926 RNA levels revealed minimal expression across multiple tissues at steady state. However, the expression of this gene was highly induced in macrophages and dendritic cells by TLR activation, in a p38 MAPK- and MyD88-dependent manner. To study the function of U90926, we generated U90926-deficient (U9-KO) mice. Surprisingly, we found minimal effects of U90926 deficiency in cultured macrophages. Given the lack of macrophage-intrinsic effect, we investigated the subcellular localization of U90926 transcript and its protein-coding potential. We found that U90926 RNA localizes to the cytosol, associates with ribosomes, and contains an open reading frame that encodes a novel glycosylated protein (termed U9-ORF), which is secreted from the cell. An in vivo model of endotoxic shock revealed that, in comparison with wild type mice, U9-KO mice exhibited increased sickness responses and mortality. Mechanistically, serum levels of IL-6 were elevated in U9-KO mice, and IL-6 neutralization improved endotoxemia outcomes in U9-KO mice. Taken together, these results suggest that U90926 expression is protective during endotoxic shock, potentially mediated by the paracrine and/or endocrine actions of the novel U9-ORF protein secreted by activated myeloid cells.

Combined Multiomics and In Silico Approach Uncovers PRKAR1A as a Putative Therapeutic Target in Multi-Organ Dysfunction Syndrome

Despite all epidemiological, clinical, and experimental research efforts, therapeutic concepts in sepsis and sepsis-induced multi-organ dysfunction syndrome (MODS) remain limited and unsatisfactory. Currently, gene expression data sets are widely utilized to discover new biomarkers and therapeutic targets in diseases. In the present study, we analyzed MODS expression profiles (comprising 13 sepsis and 8 control samples) retrieved from NCBI-GEO and found 359 differentially expressed genes (DEGs), among which 170 were downregulated and 189 were upregulated. Next, we employed the weighted gene co-expression network analysis (WGCNA) to establish a MODS-associated gene co-expression network (weighted) and identified representative module genes having an elevated correlation with age. Based on the results, a turquoise module was picked as our hub module. Further, we constructed the PPI network comprising 35 hub module DEGs. The DEGs involved in the highest-confidence PPI network were utilized for collecting pathway and gene ontology (GO) terms using various libraries. Nucleotide di- and triphosphate biosynthesis and interconversion was the most significant pathway. Also, 3 DEGs within our PPI network were involved in the top 5 significantly enriched ontology terms, with hypercortisolism being the most significant term. PRKAR1A was the overlapping gene between top 5 significant pathways and GO terms, respectively. PRKAR1A was considered as a therapeutic target in MODS, and 2992 ligands were screened for binding with PRKAR1A. Among these ligands, 3 molecules based on CDOCKER score (molecular dynamics simulated-based score, which allows us to rank the binding poses according to their quality and to identify the best pose for each system) and crucial interaction with human PRKAR1A coding protein and protein kinase-cyclic nucleotide binding domains (PKA RI alpha CNB-B domain) via active site binding residues, viz. Val283, Val302, Gln304, Val315, Ile327, Ala336, Ala337, Val339, Tyr373, and Asn374, were considered as lead molecules.

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.

Aetiology, clinical parameters and outcome in 113 dogs surgically treated for septic peritonitis (2004-2020)

BACKGROUND

Septic peritonitis (SP) is a common life-threatening condition. The aims of this study were to describe the aetiology, clinicopathological abnormalities, complications, treatment, outcome and prognosis of dogs with SP.

METHODS

Records of 113 dogs diagnosed and surgically treated for SP between 2004 and 2020 were reviewed.

RESULTS

Overall survival rate was 74.3%. Parameters at presentation that were significantly associated with mortality were lateral recumbency (p = 0.001) and elevated respiratory rate (p = 0.045). Hypotension during or after surgery (p < 0.001), liver injury (p < 0.001) and acute kidney injury (p < 0.001) were also more common in non-survivors. The source of contamination, number of surgeries or the location of perforation in cases of gastrointestinal tract perforation were not associated with mortality. Delta glucose (serum vs. abdominal) was available in 36 out of 113 dogs and the difference was more than 20 mg/dl in only 22 of out 36 (61.1%) cases.

CONCLUSION

Liver and kidney injuries play a role in mortality, and early diagnosis and intervention are recommended to prevent multiple organ dysfunction and death. The reported high sensitivity of delta glucose is questionable in diagnosis of SP.

IDENTIFICATION OF SUBPHENOTYPES OF SEPSIS-ASSOCIATED LIVER DYSFUNCTION USING CLUSTER ANALYSIS

ABSTRACT

Objectives: We attempted to identify and validate the subphenotypes of sepsis-associated liver dysfunction (SALD) using routine clinical information. Design: This article is a retrospective observational cohort study. Setting: We used the Medical Information Mart for Intensive Care IV database and the eICU Collaborative Research Database. Patients: We included adult patients (age ≥18 years) who developed SALD within the first 48 hours of intensive care unit (ICU) admission. We excluded patients who died or were discharged from the ICU within the first 48 hours of admission. Patients with abnormal liver function before ICU admission were also excluded. Measurements and Main Results: Patients in the MIMIC-IV 1.0 database served as a derivation cohort. Patients in the eICU database were used as validation cohort. We identified four subphenotypes of SALD (subphenotype α, β, γ, δ) using K-means cluster analysis in 5234 patients in derivation cohort. The baseline characteristics and clinical outcomes were compared between the phenotypes using one-way analysis of variance/Kruskal-Wallis test and the χ 2 test. Moreover, we used line charts to illustrate the trend of liver function parameters over 14 days after ICU admission. Subphenotype α (n = 1,055) was the most severe cluster, characterized by shock with multiple organ dysfunction (MODS) group. Subphenotype β (n = 1,179) had the highest median bilirubin level and the highest proportion of patients with underlying liver disease and coexisting coagulopathy (increased bilirubin group). Subphenotype γ (n = 1,661) was the cluster with the highest mean age and had the highest proportion of patients with chronic kidney disease (aged group). Subphenotype δ (n = 1,683) had the lowest 28-day and in-hospital mortality (mild group). The characteristics of clusters in the validation cohort were similar to those in the derivation cohort. In addition, we were surprised to find that GGT levels in subphenotype δ were significantly higher than in other subphenotypes, showing a different pattern from bilirubin. Conclusions: We identified four subphenotypes of SALD that presented with different clinical features and outcomes. These results can provide a valuable reference for understanding the clinical characteristics and associated outcomes to improve the management of patients with SALD in the ICU.

A predictive model for prognosis in very low birth weight infants with late-onset sepsis

OBJECTIVES

This study aims to develop a predictive model to assess the probability of poor prognosis in very low birth weight infants (VLBWI) with late-onset sepsis (LOS).

METHODS

A total of 309 eligible VLBWI with LOS were included in the study. Logistic regression was used to determine prognostic factors for VLBWI with LOS. A nomogram incorporating these factors was created to predict the probability of poor prognosis. Poor prognosis includes death and survival with severe complications.

RESULTS

In the developmental cohort, the incidence of poor prognosis was 59.5% (147/247). Forward stepwise logistic regression analysis showed that HCO3, albumin (ALB), ionized calcium (iCa), blood urea nitrogen (BUN), gestational age (GA), and birth weight (BW) were independent predictors of poor prognosis in VLBWI with LOS. The predictive model showed good discrimination and calibration. In the developmental cohort, the prediction model had a sensitivity of 83.7%, a specificity of 74.0%, and a C-index of 0.845 (95% confidence interval: 0.795-0.894).

CONCLUSION

Our study identified independent predictors of poor prognosis in VLBWI with LOS and used them to construct a predictive model. This model can help clinicians to identify high-risk groups with poor prognosis early and provide important clinical reference information.

IMPACT

This article highlights the development of a predictive model to assess the probability of poor prognosis in very low birth weight infants with late-onset sepsis (LOS). The model constructed in this manuscript was the first model to predict the poor prognosis of VLBWI with LOS. We mean a poor prognosis that includes death and some severe complications that may lead to long-term disability. Clinicians can use the model's scoring results to assess a patient's condition and accurately identify the occurrence of poor prognosis.

Deficiency of S100A9 Alleviates Sepsis-Induced Acute Liver Injury through Regulating AKT-AMPK-Dependent Mitochondrial Energy Metabolism

Acute liver injury (ALI) is recognized as a serious complication of sepsis in patients in intensive care units (ICUs). S100A8/A9 is known to promote inflammation and immune responses. However, the role of S100A8/A9 in the regulation of sepsis-induced ALI remains known. Our results indicated that S100A8/A9 expression was significantly upregulated in the livers of septic mice 24 h after cecal ligation and a puncture (CLP) operation. Moreover, S100A9-KO in mice markedly attenuated CLP-induced liver dysfunction and injury, promoting the AMPK/ACC/GLUT4-mediated increases in fatty acid and glucose uptake as well as the improvement in mitochondrial function and ATP production. In contrast, treatment with the AMPK inhibitor Compound C reversed the inhibitory effects of S100A9 KO on CLP-induced liver dysfunction and injury in vivo. Finally, the administration of the S100A9 inhibitor Paquinimod (Paq) to WT mice protected against CLP-induced mortality, liver injury and mitochondrial dysfunction. In summary, our findings demonstrate for the first time that S100A9 plays an important pro-inflammatory role in sepsis-mediated ALI by regulating AKT-AMPK-dependent mitochondrial energy metabolism and highlights that targeting S100A9 may be a promising new approach for the prevention and treatment of sepsis-related liver injury.

Temporal Supervised Contrastive Learning for Modeling Patient Risk Progression

We consider the problem of predicting how the likelihood of an outcome of interest for a patient changes over time as we observe more of the patient's data. To solve this problem, we propose a supervised contrastive learning framework that learns an embedding representation for each time step of a patient time series. Our framework learns the embedding space to have the following properties: (1) nearby points in the embedding space have similar predicted class probabilities, (2) adjacent time steps of the same time series map to nearby points in the embedding space, and (3) time steps with very different raw feature vectors map to far apart regions of the embedding space. To achieve property (3), we employ a nearest neighbor pairing mechanism in the raw feature space. This mechanism also serves as an alternative to "data augmentation", a key ingredient of contrastive learning, which lacks a standard procedure that is adequately realistic for clinical tabular data, to our knowledge. We demonstrate that our approach outperforms state-of-the-art baselines in predicting mortality of septic patients (MIMIC-III dataset) and tracking progression of cognitive impairment (ADNI dataset). Our method also consistently recovers the correct synthetic dataset embedding structure across experiments, a feat not achieved by baselines. Our ablation experiments show the pivotal role of our nearest neighbor pairing.

Fish Oil - Omega-3 Exerts Protective Effect in Oxidative Stress and Liver Dysfunctions Resulting from Experimental Sepsis

Background

Sepsis is a severe global health problem, with high morbidity and mortality. In sepsis, one of the main affected organs is the liver. Hepatic alterations characterize a negative prognostic. Omega-3 fatty acids (ω3), eicosapentaenoic acid, and docosahexaenoic acid, are part of the main families of polyunsaturated fatty acids. ω3 has been used in studies as sepsis treatment and as a treatment for non-alcoholic liver disease.

Aim

We aimed to evaluate the effects of treatment with fish oil (FO) rich in ω3 on liver changes and damage resulting from experimental sepsis.

Methodology

A model of severe sepsis in Wistar rats was used. Oxidative stress in the liver tissue was evaluated by means of tests of thiobarbituric acid reactive substances, 2,7-dihydrodichlorofluorescein diacetate , catalase, and glutathione peroxidase, in the serum TBARS, DCF, thiols and, to assess liver dysfunction, alanine aminotransferase and aspartate aminotransferase. Hepatic tissue damage was evaluated using H&E histology.

Results

In assessments of oxidative stress in liver tissue, a protective effect was observed in the tests of TBARS, DCF, CAT, and GPx, when compared the sepsis versus sepsis+ω3 groups. Regarding the oxidative stress in serum, a protective effect of treatment with ω3 was observed in the TBARS, DCF, and thiols assays, in the comparison between the sepsis and sepsis+ω3 groups. ω3 had also a beneficial effect on biochemical parameters in serum in the analysis of ALT, creatinine, urea, and lactate, observed in the comparison between the sepsis and sepsis+ω3 groups.

Conclusion

The results suggest ω3 as a liver protector during sepsis with an antioxidant effect, alleviating injuries and dysfunctions.

Association between heme oxygenase one and sepsis development in patients with moderate-to-critical COVID-19: a single-center, retrospective observational study

BACKGROUND

Heme oxygenase one (HO-1) is considered a poor prognostic factor for survival in patients with severe-to-critical coronavirus disease (COVID-19), but the clinical correlation between heme catabolism biomarkers and COVID-19-related sepsis is unknown. The etiopathogenetic hypothesis of HO-1 response during sepsis in patients with poor prognosis should be clarified. This study aimed to investigate sepsis development within 48 h following moderate-to-critical COVID-19 and examined heme/HO-1 catabolism biomarkers associated with sepsis. We also studied the HO-1 and traditional prognostic factors for predicting survival in patients with COVID-19.

METHODS

This retrospective observational study included patients unvaccinated for COVID-19 with moderate-to-critical COVID-19 (n = 156) who had been admitted to Taipei Tzu Chi Hospital in 2021. All COVID-19 patients were diagnosed by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reverse transcriptase polymerase chain reaction. For analysis of heme catabolism in SARS-CoV-2-induced sepsis, we excluded patients with co-infection and severe anemia. Heme catabolism biomarkers were compared between groups of patients with COVID-19 and sepsis (sepsis) and those with COVID-19 without sepsis (no sepsis), and a control group comprising 100 healthy individuals. All clinical and laboratory data were collected retrospectively and blood specimens were collected from Biobank. Multivariable logistic regression analysis was used to compare all variables between the sepsis and no-sepsis groups. Cox regression analysis was used to determine predictors of survival in patients with COVID-19.

RESULTS

There were 71 and 85 patients with and without sepsis, respectively. Heme and HO-1 levels differed significantly between the sepsis, no sepsis, and control groups. In multivariate analysis, confusion, blood urea nitrogen, respiration, blood pressure in patients aged > 65 years (CURB-65) (adjusted odds ratio [aOR] 5.331, 95% confidence interval [CI] 2.587-10.987; p < 0.001), albumin (aOR 0.139, 95% CI 0.003-0.636; p = 0.01), D-dimer (aOR 1.001, 95% CI 1.000-1.002; p = 0.032), and HO-1 (aOR 1.116, 95% CI 1.055-1.180; p < 0.001) were significantly associated with 48-h sepsis episodes after adjusting for other confounding factors. HO-1 levels were also significantly associated with 48-h Sequential Organ Failure Assessment Score (SOFA) scores. However, HO-1 did not significantly increase the hazard of in-hospital mortality in moderate-to-critical COVID-19 by Cox regression analysis.

CONCLUSIONS

HO-1 levels increased with sepsis development within 48 h of admission for COVID-19 after adjusting for other risk factors, but no significant association was observed between HO-1 and COVID-19 mortality. We suppose that HO-1 may have protective effect in early sepsis, but further clinical multicenter prospective studies are needed.

Recent nanoengineered diagnostic and therapeutic advancements in management of Sepsis

COVID-19 acquired symptoms have affected the worldwide population and increased the load of Intensive care unit (ICU) patient admissions. A large number of patients admitted to ICU end with a deadly fate of mortality. A high mortality rate of patients was reported with hospital-acquired septic shock that leads to multiple organ failures and ultimately ends with death. The patients who overcome this septic shock suffer from morbidity that also affects their caretakers. To overcome these situations, scientists are exploring progressive theragnostic techniques with advanced techniques based on biosensors, biomarkers, biozymes, vesicles, and others. These advanced techniques pave the novel way for early detection of sepsis-associated symptoms and timely treatment with appropriate antibiotics and immunomodulators and prevent the undue effect on other parts of the body. There are other techniques like externally modulated electric-based devices working on the principle of piezoelectric mechanism that not only sense the endotoxin levels but also target them with a loaded antibiotic to neutralize the onset of inflammatory response. Recently researchers have developed a lipopolysaccharide (LPS) neutralizing cartridge that not only senses the LPS but also appropriately neutralizes with dual mechanistic insights of antibiotic and anti-inflammatory effects. This review will highlight recent developments in the new nanotechnology-based approaches for the diagnosis and therapeutics of sepsis that is responsible for the high number of deaths of patients suffering from this critical disease.

The gut–liver axis in sepsis: interaction mechanisms and therapeutic potential

Sepsis is a potentially fatal condition caused by dysregulation of the body's immune response to an infection. Sepsis-induced liver injury is considered a strong independent prognosticator of death in the critical care unit, and there is anatomic and accumulating epidemiologic evidence that demonstrates intimate cross talk between the gut and the liver. Intestinal barrier disruption and gut microbiota dysbiosis during sepsis result in translocation of intestinal pathogen-associated molecular patterns and damage-associated molecular patterns into the liver and systemic circulation. The liver is essential for regulating immune defense during systemic infections via mechanisms such as bacterial clearance, lipopolysaccharide detoxification, cytokine and acute-phase protein release, and inflammation metabolic regulation. When an inappropriate immune response or overwhelming inflammation occurs in the liver, the impaired capacity for pathogen clearance and hepatic metabolic disturbance can result in further impairment of the intestinal barrier and increased disruption of the composition and diversity of the gut microbiota. Therefore, interaction between the gut and liver is a potential therapeutic target. This review outlines the intimate gut–liver cross talk (gut–liver axis) in sepsis.

Koumine regulates macrophage M1/M2 polarization via TSPO, alleviating sepsis-associated liver injury in mice

BACKGROUND

Translocator protein (TSPO) is an 18-kDa transmembrane protein found primarily in the mitochondrial outer membrane, and it is implicated in inflammatory responses, such as cytokine release. Koumine (KM) is an indole alkaloid extracted from Gelsemium elegans Benth. It has been reported to be a high-affinity ligand of TSPO and to exert anti-inflammatory and immunomodulatory effects in our recent studies. However, the protective effect of KM on sepsis-associated liver injury (SALI) and its mechanisms are unknown.

PURPOSE

To explore the role of TSPO in SALI and then further explore the protective effect and mechanism of KM on SALI.

METHODS

The effect of KM on the survival rate of septic mice was confirmed in mouse models of caecal ligation and puncture (CLP)-induced and lipopolysaccharide (LPS)-induced sepsis. The protective effect of KM on CLP-induced SALI was comprehensively evaluated by observing the morphology of the mouse liver and measuring liver injury markers. The serum cytokine content was detected in mice by flow cytometry. Macrophage polarization in the liver was examined using western blotting. TSPO knockout mice were used to explore the role of TSPO in sepsis liver injury and verify the protective effect of KM on sepsis liver injury through TSPO.

RESULTS

KM significantly improved the survival rate of both LPS- and CLP-induced sepsis in mice. KM has a significant liver protective effect on CLP-induced sepsis in mice. KM treatment ameliorated liver ischaemia, improved liver pathological injuries, and decreased the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH) and proinflammatory cytokines in serum. Western blotting results showed that KM inhibited M1 polarization of macrophages and promoted M2 polarization. In TSPO knockout mice, we found that TSPO knockout can improve the survival rate of septic mice, ameliorate liver ischaemia, improve liver pathological injuries, and decrease the levels of ALT, AST, and LDH. In addition, TSPO knockout inhibits the M1 polarization of macrophages in the liver of septic mice and promotes M2 polarization and the serum levels of proinflammatory cytokines. Interestingly, in TSPO knockout septic mice, these protective effects of KM were no longer effective.

CONCLUSIONS

We report for the first time that TSPO plays a critical role in sepsis-associated liver injury by regulating the polarization of liver macrophages and reducing the inflammatory response. KM, a TSPO ligand, is a potentially desirable candidate for the treatment of SALI that may regulate macrophage M1/M2 polarization through TSPO in the liver.

Evaluation of Resting Serum Bile Acid Concentrations in Dogs with Sepsis

Recent studies in the human literature suggest that serum bile acid concentrations could be an early predictor of short-term survival in critically ill patients. However, there is no available information in the veterinary literature regarding serum bile acid concentrations in dogs with sepsis. We aimed to evaluate if resting serum bile acid concentrations differ between septic and non-septic dogs. This was a retrospective observational study, of medical records at a single referral center over a twelve-year period. Twenty-six client-owned dogs diagnosed with sepsis were identified. Twenty-one dogs presenting with a non-hepatobiliary systemic disease and twenty-nine dogs admitted for an elective orthopedic procedure, considered otherwise healthy, were selected as control groups. Resting serum bile acid concentrations were significantly higher in the septic compared to the non-septic groups (ill control and orthopedic control groups). However, when assessing bile acid concentrations between groups individually, no difference was identified between the septic and the orthopedic control group. These results should be interpreted cautiously.

Immunomodulation by Hemoadsorption—Changes in Hepatic Biotransformation Capacity in Sepsis and Septic Shock: A Prospective Study

Background: Sepsis is often associated with liver dysfunction, which is an indicator of poor outcomes. Specific diagnostic tools that detect hepatic dysfunction in its early stages are scarce. So far, the immune modulatory effects of hemoadsorption with CytoSorb^® on liver function are unclear. Method: We assessed the hepatic function by using the dynamic LiMAx^® test and biochemical parameters in 21 patients with sepsis or septic shock receiving CytoSorb^® in a prospective, observational study. Points of measurement: T₁: diagnosis of sepsis or septic shock; T₂ and T₃: 24 h and 48 h after the start of CytoSorb^®; T₄: 24 h after termination of CytoSorb^®. Results: The hepatic biotransformation capacity measured by LiMAx^® was severely impaired in up to 95 % of patients. Despite a rapid shock reversal under CytoSorb^®, a significant improvement in LiMAx^® values appeared from T₃ to T₄. This decline and recovery of liver function were not reflected by common parameters of hepatic metabolism that remained mostly within the normal range. Conclusions: Hepatic dysfunction can effectively and safely be diagnosed with LiMAx^® in ventilated ICU patients under CytoSorb^®. Various static liver parameters are of limited use since they do not adequately reflect hepatic dysfunction and impaired hepatic metabolism.

Polygonatum sibiricum Polysaccharides Attenuate Lipopoly-Saccharide-Induced Septic Liver Injury by Suppression of Pyroptosis via NLRP3/GSDMD Signals

Sepsis is a systemic inflammatory response syndrome with high mortality. Acute liver injury is an independent predictor for poor prognosis in septic patients. Polygonatum sibiricum polysaccharides (PSP) have been reported to possess anti-inflammatory and hepatoprotective activities. To evaluate the effects of PSP on septic liver injury and demonstrate the potential molecular mechanisms, the septic acute liver injury (SALI) model was established in BALB/c mice via intraperitoneal injection of lipopolysaccharide (LPS). We found that PSP treatment could remarkably reduce the 48 h mortality rate of septic mice; alleviate liver histopathologic damage; lower the activity of neutrophil infiltration marker MPO in liver tissue; and decrease the levels of liver function indexes AST, ALT, ALP, and TBIL, inflammatory cytokines TNFα and IL-6, and pyroptosis-related inflammatory cytokines IL-18 and IL-1β in serum. TUNEL staining and detecting GSDMD-NT protein expression level in liver tissue revealed that PSP could restrain excessive pyroptosis. In addition, PSP treatment reversed the upregulations of mRNA expression levels of the NLRP3/GSDMD signals in the liver. Our results indicated the potential protective role of PSP against SALI by inhibiting pyroptosis via NLRP3/GSDMD signals.

BACH1-Hemoxygenase-1 axis regulates cellular energetics and survival following sepsis

Sepsis is a complex disease due to dysregulated host response to infection. Oxidative stress and mitochondrial dysfunction leading to metabolic dysregulation are among the hallmarks of sepsis. The transcription factor NRF2 (Nuclear Factor E2-related factor2) is a master regulator of the oxidative stress response, and the NRF2 mediated antioxidant response is negatively regulated by BTB and CNC homology 1 (BACH1) protein. This study tested whether Bach1 deletion improves organ function and survival following polymicrobial sepsis induced by cecal ligation and puncture (CLP). We observed enhanced post-CLP survival in Bach1-/- mice with a concomitantly increased liver HO-1 expression, reduced liver injury and oxidative stress, and attenuated systemic and tissue inflammation. After sepsis induction, the liver mitochondrial function was better preserved in Bach1-/- mice. Furthermore, BACH1 deficiency improved liver and lung blood flow in septic mice, as measured by SPECT/CT. RNA-seq analysis identified 44 genes significantly altered in Bach1-/- mice after sepsis, including HMOX1 and several genes in lipid metabolism. Inhibiting HO-1 activity by Zinc Protoporphyrin-9 worsened organ function in Bach1-/- mice following sepsis. We demonstrate that mitochondrial bioenergetics, organ function, and survival following experimental sepsis were improved in Bach1-/- mice through the HO-1-dependent mechanism and conclude that BACH1 is a therapeutic target in sepsis.

TSLP protects against sepsis-induced liver injury by inducing autophagy via activation of the PI3K/Akt/STAT3 pathway

BACKGROUND

Liver injury is the main factor in multiple organ failure caused by sepsis. Thymic stromal lymphopoietin (TSLP) is derived from epithelial cells and plays an important role in inflammation, allergies and cancer. The role of TSLP in sepsis-induced liver injury (SILI) is unclear. The purpose of this study was to investigate the effect of TSLP on sepsis-induced liver injury and to clarify the mechanism.

METHODS

Wild-type (WT) mice and TSLPR knockout (TSLPR^-/-) mice were subjected to cecal ligation and puncture (CLP) to generate a SILI model. Liver injury was assessed by measuring the levels of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), histologic liver injury scores, hepatocyte death, and liver inflammatory factors. Signal pathways were explored in vivo to identify possible mechanisms for TSLP in SILI.

RESULTS

The expression of TSLP and TSLPR increased during SILI. Deletion of TSLPR exacerbated liver injury in terms of serum ALT, AST, histologic liver injury scores, and liver inflammatory factors. Compared with controls, administration of exogenous recombinant mouse TSLP reduced liver injury in WT mice during SILI, but failed to reduce liver injury in TSLPR^-/- mice. TSLP induced autophagy in hepatocytes during SILI. Mechanistically, Akt and STAT3 were activated in WT mice during SILI. The opposite results were observed in TSLPR^-/- mice. In addition, the protective effects of TSLP in WT mice were blocked by PI3K inhibitor, LY294002, during SILI.

CONCLUSION

These results suggest that TSLP can improve liver injury caused by sepsis and its specific mechanism may be related to inducing autophagy through the PI3K/Akt/STAT3 signaling pathway.

Impact of indirect bilirubin and uric acid on outcomes of sepsis-associated acute kidney injury (sAKI)

BACKGROUND

Acute kidney injury (AKI) is one of the most frequent pathophysiologic disorders encountered in hospitalized patients, with sepsis frequently implicated in pathogenesis. Reactive oxygen species (ROS) seem to have a significant contribution to sepsis-induced AKI. Proposed mechanisms include induction of cell membrane lipid peroxidation, protein denaturing, and direct DNA damage, all of which have deleterious effect. These changes constitute oxidative injury to the kidneys.

OBJECTIVE

To evaluate the antioxidant actions of indirect bilirubin and uric acid on outcomes of sepsis-associated AKI.

METHODS

Ninety-eight patients admitted to the intensive care unit (ICU), at a large tertiary center, with sepsis and AKI were evaluated for serum levels of uric acid, bilirubin (primarily indirect), and procalcitonin. The primary endpoints studied were the need for hemodialysis and death.

RESULTS

Thirty-two (33%) patients developed AKI requiring hemodialysis (HD). These patients had higher SOFA scores (p < 0.001) and lower levels of indirect bilirubin (p < 0.001) compared to those not requiring HD. There was no statistically significant difference in serum uric acid levels. Logistic regression analysis identified creatinine level, total and indirect bilirubin levels, and leukocyte count as significant predictors of patient death.

CONCLUSION

Higher leukocyte counts and creatinine levels were independently associated with poor outcomes in ICU patients with sepsis. Additionally, lower indirect bilirubin levels were also noted to be associated with similar outcomes. The latter provides insights into oxidative stress as a major player in the pathogenesis of sepsis-induced AKI, with a potential protective role of indirect bilirubin.