Mesenchymal Stem Cells Promote Polarization of M2 Macrophages in Mice with Acute-On-Chronic Liver Failure via Mertk/JAK1/STAT6 Signaling.

Acute-on-chronic liver failure (ACLF) is a severe disease with a high mortality. Macrophage-related inflammation plays a crucial role in ACLF development. Mesenchymal stem cells (MSCs) treatment was demonstrated to be beneficial in ACLF in our previous study; however, the underlying mechanisms remain unknown. Therefore, mouse bone marrow-derived MSCs were used to treat an ACLF mouse model or cocultured with RAW264.7/J774A.1 macrophages that were stimulated with LPS. Histological and serological parameters and survival were analyzed to evaluate efficacy. We detected changes of Mer tyrosine kinase (Mertk), JAK1/STAT6, inflammatory cytokines, and markers of macrophage polarization in vitro and in vivo. In ACLF mice, MSCs improved liver function and 48-h survival of ACLF mice and alleviated inflammatory injury by promoting M2 macrophage polarization and elevated Mertk expression levels in macrophages. This is significant, as Mertk regulates M2 macrophage polarization via the JAK1/STAT6 signaling pathway.

The impact of serum thyroid-stimulation hormone levels on the outcome of hepatitis B virus related acute-on-chronic liver failure: an observational study.

BACKGROUND: Thyroid dysfunction has been reported in severe liver diseases. The aim of this study was to analyze the impact of serum thyroid-stimulation hormone (TSH) levels on the prognosis of patients with hepatitis B virus (HBV)-related acute-on-chronic liver failure (ACLF). METHODS: This retrospective cohort study included 1,862 patients with HBV-related ACLF. Risk factors associated with 30-day and 90-day survival, hazard ratios (HRs), and 95% confidence intervals (CIs) for TSH were estimated using Cox proportional hazards regression. The Area Under the ROC curve (AUROC) analysis was carried out, and the cut-off values were calculated. After grouping by the cut-off value, survival was compared between the groups using the log-rank test. This study data is from the "Survival Cohort Study (SCS)", which has been registered at ClinicalTrials.gov (NCT03992898). RESULTS: Multivariate analysis indicated that an elevated TSH level was a highly significant predictor for 30-day survival (HR = 0.743, 95% CI: 0.629-0.878, P < 0.001) and 90-day survival (HR = 0.807, 95% CI: 0.717-0.909, P < 0.001). The AUROC of TSH level for 30-day and 90-day mortality were 0.655 and 0.620, respectively, with the same best cut-off values of 0.261 µIU/mL. Log-rank test showed that the group with higher TSH level had higher 30-day (78.5%, 95% CI: 76.1%-80.9% vs. 56.9%, 95% CI: 53.4%-60.4%; P < 0.001) and 90-day survival rate (61.5%, 95% CI: 58.6%-64.4% vs. 42.8%, 95% CI: 39.3%-46.3%; P < 0.001). Similar findings were observed in subgroups analysis. After adjusting for age and other risk factors, the higher level of TSH remained associated with 30-day survival (HR = 0.602, 95% CI: 0.502-0.721, P < 0.001) and 90-day survival (HR = 0.704, 95% CI, 0.609-0.814, P < 0.001). CONCLUSIONS: Serum TSH level significantly correlate with HBV-related ACLF patients' survival and may be of value for predicting 30-day and 90-day survival of patients with HBV-related ACLF.

Med1 inhibits ferroptosis and alleviates liver injury in acute liver failure via Nrf2 activation.

BACKGROUND: Extensive hepatocyte mortality and the absence of specific medical therapy significantly contribute to the unfavorable prognosis of acute liver failure (ALF). Ferroptosis is a crucial form of cell death involved in ALF. In this study, we aimed to determine the impact of Mediator complex subunit 1 (Med1) on ferroptosis and its potential hepatoprotective effects in ALF. RESULTS: Med1 expression is diminished in the liver of lipopolysaccharide (LPS)/D-galactosamine (D-GalN)-induced ALF mice, as well as in hepatocytes damaged by H2O2 or TNF-α/D-GalN in vitro. Med1 overexpression mitigates liver injury and decreases the mortality rate of ALF mice by ferroptosis inhibition. The mechanism by which Med1 inhibits erastin-induced ferroptosis in hepatocytes involves the upregulation of nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream antioxidant genes heme oxygenase-1 (HO-1), glutamate cysteine ligase catalytic (GCLC), and NAD(P)H quinone oxidoreductase 1 (NQO1). Furthermore, Med1 overexpression suppresses the transcription of proinflammatory cytokines tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in the liver of mice with LPS/D-GalN-induced ALF. CONCLUSION: Overall, our research findings indicate that Med1 suppresses ferroptosis and alleviates liver injury in LPS/D-GalN-induced ALF through the activation of Nrf2. These findings substantiate the therapeutic viability of targeting the Med1-Nrf2 axis as a means of treating individuals afflicted with ALF.

Safety and efficacy of Thymosin α1 in the treatment of hepatitis B virus-related acute-on-chronic liver failure: a randomized controlled trial.

BACKGROUND/PURPOSE OF THE STUDY: Mortality from hepatitis B virus (HBV)-related acute-on-chronic liver failure (ACLF) is high. Severe infection is the most important complication that affects the outcomes of ACLF patients. Thymosin α1 (Tα1) can improve immune imbalance and this study aimed to investigate the safety and efficacy of Tα1 treatment for HBV-related ACLF. METHODS: From 2017 to 2019, 120 patients with HBV-related ACLF were enrolled in this open-label, randomized, and controlled clinical trial (ClinicalTrial ID: NCT03082885). The control group (N = 58) was treated with standard medical therapy (SMT) only. The experimental group (N = 56) was subcutaneously injected with 1.6 mg of Tα1 once a day for the first week and then twice a week from week 2 to week 12. RESULTS: The 90-day cumulated liver transplantation free survival rate of the Tα1 group was 75.0% (95% confidence interval 63.2-86.8%) versus 53.4% (95% confidence interval 39.7-67.1%) for the SMT group (p = 0.030). No significant difference was found in the survival using competitive risk analysis. The incidences of new infection and hepatic encephalopathy in the Tα1 group were much lower than those in the SMT group (32.1% vs 58.6%, p = 0.005; 8.9% vs 24.1%, p = 0.029, respectively). Mortality from severe infection in the SMT group was higher than in the Tα1 group (24.1% vs 8.9%, p = 0.029). CONCLUSION: Tα1 is safe for patients with HBV-related ACLF and significantly improves the 90-day liver transplantation-free survival rate. There may be a subgroup which may benefit from Tα1 therapy by the mechanism of preventing infection.

Derivation and Validation of a Nomogram for Predicting 90-Day Survival in Patients With HBV-Related Acute-on-Chronic Liver Failure.

Background: Conventional prognostic models do not fully reflect the severity of hepatitis B virus (HBV)-related acute-on-chronic liver failure (ACLF). This study aimed to establish an effective and convenient nomogram for patients with HBV-related ACLF. Methods: A nomogram was developed based on a retrospective cohort of 1,353 patients treated at the Third Affiliated Hospital of Sun Yat-sen University from January 2010 to June 2016. The predictive accuracy and discriminatory ability of the nomogram were determined by a concordance index (C-index) and calibration curve, and were compared with current scoring systems. The results were validated using an independent retrospective cohort of 669 patients consecutively treated at the same institution from July 2016 to March 2018. This study is registered at ClinicalTrials.gov (NCT03992898). Results: Multivariable analysis of the derivation cohort found that independent predictors of 90-day survival were age, white blood cell (WBC) count, hemoglobin (Hb), aspartate aminotransferase (AST), total bilirubin (TBil), international normalized ratio, serum creatinine (Cr), alpha fetoprotein (AFP), serum sodium (Na), hepatic encephalopathy (HE), pre-existing chronic liver disease(PreLD), and HBV DNA load. All factors were included in the nomogram. The nomogram calibration curve for the probability of 90-day survival indicated that nomogram-based predictions were in good agreement with actual observations. The C-index of the nomogram was 0.790, which was statistically significantly greater than those for the current scoring systems in the derivation cohort (P < 0.001). The results were confirmed in the validation cohort. Conclusions: The proposed nomogram is more accurate in predicting the 90-day survival of patients with HBV-related ACLF than current commonly used methods.