Prodromal fever indicates a high risk of liver failure in acute hepatitis B

Overview of ferroptosis and pyroptosis in acute liver failure

In this editorial, we comment on the article by Zhou et al published in a recent issue. We specifically focus on the crucial roles of ferroptosis and pyroptosis in acute liver failure (ALF), a disease with high mortality rates. Ferroptosis is the result of increased intracellular reactive oxygen species due to iron accumulation, glutathione (GSH) depletion, and decreased GSH peroxidase 4 activity, while pyroptosis is a procedural cell death mediated by gasdermin D which initiates a sustained inflammatory process. In this review, we describe the characteristics of ferroptosis and pyroptosis, and discuss the involvement of the two cell death modes in the onset and development of ALF. Furthermore, we summarize several interfering methods from the perspective of ferroptosis and pyroptosis for the alleviation of ALF. These observations might provide new targets and a theoretical basis for the treatment of ALF, which are also crucial for improving the prognosis of patients with ALF.

Acute liver failure in low-income and middle-income countries

Acute liver failure is a rare condition involving the rapid development, progression, and worsening of liver dysfunction, characterised by coagulopathy and encephalopathy, and has a high mortality unless liver transplantation is performed. Population-based studies are scarce, and most published data are from high-income countries, where the main cause of acute liver failure is paracetamol overdose. This Review provides an overview of the scanty literature on acute liver failure in low-income and middle-income countries, where patients are often admitted to primary care hospitals and viral hepatitis (especially hepatitis E), tropical infections (eg, dengue), traditional medicines, and drugs (especially anti-tuberculosis drugs) have an important role. We discuss incidence, cause, occurrence in children and pregnant women, prognostic factors and scores, treatment, and mortality. To conclude, we advocate for international collaboration, the establishment of central registries for the condition, and better diagnostics.

When ferroptosis meets pathogenic infections

Apoptosis, necrosis, or autophagy are diverse types of regulated cell death (RCD), recognized as the strategies that host cells use to defend against pathogens such as viruses, bacteria, or fungi. Pathogens can induce or block different types of host cell RCD, promoting propagation or evading host immune surveillance. Ferroptosis is a newly identified RCD. Evidence has demonstrated how pathogens regulate ferroptosis to promote their replication, dissemination, and pathogenesis. However, the interaction between ferroptosis and pathogenic infections still needs to be completely elucidated. This review summarizes the advances in the interaction between pathogenic infections and host ferroptotic processes, focusing on the underlying mechanisms of how pathogens exploit ferroptosis, and discussing possible therapeutic measures against pathogen-associated diseases in a ferroptosis-dependent manner.

HBx facilitates ferroptosis in acute liver failure via EZH2 mediated SLC7A11 suppression

Background

Acute liver failure (ALF) is a syndrome of severe hepatocyte injury with high rate of mortality. Hepatitis B virus (HBV) infection is the major cause of ALF worldwide, however, the underlying mechanism by which HBV infection leads to ALF has not been fully disclosed.

Methods

D-GalN-induced hepatocyte injury model and LPS/D-GalN-induced ALF mice model were used to investigate the effects of HBV X protein (HBx) in vitro and in vivo, respectively. Cell viability and the levels of Glutathione (GSH), malondialdehyde (MDA) and iron were measured using commercial kits. The expression of ferroptosis-related molecules were detected by qRT-PCR and western blotting. Epigenetic modification and protein interaction were detected by chromatin immunoprecipitation (ChIP) assay and co-immunoprecipitation (co-IP), respectively. Mouse liver function was assessed by measuring aspartate aminotransferase (AST) and alanine aminotransferase (ALT). The histological changes in liver tissues were monitored by hematoxylin and eosin (H&E) staining, and SLC7A11 immunoreactivity was assessed by immunohistochemistry (IHC) analysis.

Results

D-GalN triggered ferroptosis in primary hepatocytes. HBx potentiated D-GalN-induced hepatotoxicity and ferroptosis in vitro, and it suppressed SLC7A11 expression through H3K27me3 modification by EZH2. In addition, EZH2 inhibition or SLC7A11 overexpression attenuated the effects of HBx on D-GalN-induced ferroptosis in primary hepatocytes. The ferroptosis inhibitor ferrostatin-1 (Fer-1) protected against ALF and ferroptosis in vivo. By contrast, HBx exacerbates LPS/D-GalN-induced ALF and ferroptosis in HBx transgenic (HBx-Tg) mice.

Conclusion

HBx facilitates ferroptosis in ALF via EZH2/H3K27me3-mediated SLC7A11 suppression.

Biological features of hepatitis B virus strains associated with fulminant hepatitis

Accumulating evidence suggests that hepatitis B virus (HBV) biological features may influence the course and clinical manifestations of infection and possibly the development of fulminant hepatitis (FH). Since HBV is not a cytocidal virus, virus-induced liver damage results from an interplay between the virus replication and the host's defense. Therefore, viral factors contributing to enhanced replication, induction of a stronger immune attack or apoptosis of hepatocytes could be crucial in development of FH. Numerous mutations in basal core promoter, pre-C, C and S regions of the HBV genome contribute to development of FH by different mechanisms, including enhanced viral replication, the loss of a decoy for immune response, unbalanced expression of viral proteins and retention of unprocessed cytotoxic proteins in hepatocytes.

Clinical Outcome and Viral Genome Variability of Hepatitis B Virus-Induced Acute Liver Failure

Acute hepatitis B virus (HBV) infection remains a frequent cause of acute liver failure (ALF) worldwide. ALF occurs in 0.1%-0.5% of infected patients. The aim of this study was to scrutinize the outcome of patients with HBV-induced ALF and mutational patterns of HBV variants, which might contribute to ALF. From 2005 to 2016, 42 patients were treated for HBV-induced ALF in the University Hospital Essen, Germany. Clinical and virological data from these patients were collected. As a control, 38 patients with acute hepatitis B (AHB) without liver failure were included. The HBV genome was sequenced by next-generation sequencing (NGS). Mutations that were found by NGS were analyzed in vitro. Of 42 patients, 8 had ALF without spontaneous recovery (NSR): Seven patients underwent liver transplantation (LT) and one patient died before LT. Of 42 patients, 34 (81%) had spontaneous recovery (SR) and cleared the infection, achieving either anti-HBs seroconversion or hepatitis B surface antigen (HBsAg) loss. HBV genotype (GT)-D was the most frequent GT in patients with ALF. Mutations in HBV core, preS2, and small hepatitis B surface antigen (SHB) were more frequent in patients with ALF-NSR compared with those with ALF-SR or AHB. Amino acid deletions (del; 16-22 and 20-22) in preS2 and SHB mutation L49R were exclusively detected in patients with ALF-NSR. In vitro analyses reveal that these mutations did not influence HBsAg secretion or infectivity. Conclusion: HBV GT-D and increased variability in HBV core, preS2 region, and SHB are associated with a worse clinical outcome of acute HBV infection.

Acute Hepatitis B with Pancreatitis and Cholecystitis Leading to Acute Liver Failure and Death

Acute liver failure is defined as severe acute liver injury, concurrent with encephalopathy and loss of hepatic synthetic function, in a patient without known pre-existing liver disease. Evaluation of acute liver failure in the emergency department should focus on identification of treatable causes. Acute liver failure from acute hepatitis B infection is a rare but potentially lethal occurrence. Multi-organ dysfunction from acute liver failure may be exacerbated by metabolic and inflammatory reactions associated with acute pancreatitis, which accompanies approximately 5% of cases of acute viral hepatitis. Transplant-free survival rate with liver failure from acute hepatitis B is unfortunately less than 20%.

Clinical course of sporadic acute hepatitis E in a hepatitis B virus endemic region

OBJECTIVES

In China, the epidemic pattern of acute hepatitis E virus (HEV) infection has changed from waterborne outbreaks to foodborne sporadic cases. However, the clinical course of sporadic acute hepatitis E (AHE) has not been well defined.

METHODS

Consecutive patients with AHE who were admitted to the Jinan Infectious Disease Hospital, Jinan, Shandong Province between January 2003 and December 2014 were evaluated and followed. Demographic data, clinical manifestations, results of laboratory tests, and outcomes were recorded. Risk factors for liver failure and death were analyzed.

RESULTS

A total of 680 patients with AHE were identified during the study period. The incidence was highest in February, March, and April, accounting for about 41% of the cases. The male to female ratio was 5.1:1 (574/106). The average age was 50.9±12.8years. The prevalence rates of prodromal fever, fatigue, loss of appetite, and jaundice were 25.6%, 85.6%, 83.8%, and 92.8%, respectively. The median (range) serum alanine aminotransferase, aspartate aminotransferase, bilirubin, albumin, and platelet levels were 727 (8-6270) U/l, 300 (17-6226) U/l, 196.8 (8.0-1083) μmol/l, 33.0 (15.2-45.8) g/l, and 162 (10-589)×10⁹/l, respectively. The prevalence of hepatitis B surface antigen (HBsAg) was 18.5% (126/680) and of liver cirrhosis was 9.4% (64/680). Thirteen percent (89/680) of the cases progressed to liver failure, including 4.1% (28/680) with acute liver failure (ALF) and 9.0% (61/680) with acute-on-chronic liver failure (ACLF). Among patients with HBsAg positivity or cirrhosis, 28.6% (36/126) and 36.0% (23/64), respectively, progressed to ACLF. Multiple logistic regression analysis indicated that age >53years, prodromal fever, HBsAg positivity, cirrhosis, and thrombocytopenia (platelet count <150×10⁹/l) were independently associated with the development of liver failure, with an odds ratio (95% confidence interval) of 2.5 (1.5-4.3), 1.9 (1.1-3.2), 3.7 (2.0-6.7), 2.1 (1.1-4.2), and 5.9 (3.3-10.4), respectively. The overall mortality was 5.6% (38/680), and the mortality rates in patients with and without underlying liver disease were 9.3% (22/237) and 3.6% (16/443), respectively. Multiple logistic regression analysis indicated that hepatic encephalopathy, bilirubin >500μmol/l, international normalized ratio (INR)>2, and severe thrombocytopenia (platelet count <100×10⁹/l) were independently associated with death, with an odds ratio (95% confidence interval) of 7.2 (2.4-21.8), 5.8 (1.9-17.2), 24.1 (7.9-73.3), and 10.8 (3.6-32.9), respectively.

CONCLUSIONS

In areas that are dual endemic for hepatitis B virus and HEV, the HEV vaccine for patients with obvious liver diseases is of significance. Thrombocytopenia is an important predictor of liver failure and mortality in sporadic AHE.