Gut Microbiota Dysbiosis Strengthens Kupffer Cell-mediated Hepatitis B Virus Persistence through Inducing Endotoxemia in Mice

Characteristics and Clinical Significance of Gut Microbiota in Patients With Epstein-Barr Virus-Associated Liver Dysfunction

Infectious mononucleosis (IM) is mainly triggered by Epstein-Barr virus (EBV) infection. There are few studies on the role of the gut microbiota in IM and EBV-associated liver dysfunction. The aim of this study was to investigate the characteristics of the gut microbiota in the EBV-associated liver dysfunction and to evaluate the relationship between the severity of gut microbiota dysbiosis and cytokine levels. A case-control study was performed. Individuals meeting the inclusion and exclusion criteria for EBV-induced IM were enrolled and their fecal and blood samples were collected. The V3-V4 region of the 16s rDNA gene of fecal microbiota was sequenced; bioinformatics analysis including α-diversity, β-diversity, and linear discriminant analysis (LDA) effect size (LEfSe) was performed; and the correlation between bacteria and clinical indices was analysed. A total of 48 participants completed fecal and blood tests, including 18 IM, 11 EBV-associated liver dysfunction, 12 healthy children and 7 EBV-negative liver dysfunction. The α-diversity and β-diversity of the gut microbiota in the EBV-associated liver dysfunction was more than that in IM. The abundance of Granulicatella, Enterococcus, Atopobium and Acinetobacter increased, while the abundance of Prevotella, Sutterella, Collinsella, Desulfovibrio decreased in the EBV-associated liver dysfunction compared with the IM. The abundance of Enterococcus, Atopobium and Acinetobacter correlated positively with the levels of IL-1β, IL-6, TNF-α and CD8+ cytotoxic T lymphocytes%. Gut microbiota of EBV-associated liver dysfunction was significantly disturbed and associated with systemic immune response.

Crosstalk between COVID-19 and the gut-brain axis: a gut feeling

The microbes in the gut are crucial for maintaining the body's immune system and overall gut health. However, it is not fully understood how an unstable gut environment can lead to more severe cases of SARS-CoV-2 infection. The gut microbiota also plays a role in the gut-brain axis and interacts with the central nervous system through metabolic and neuroendocrine pathways. The interaction between the microbiota and the host's body involves hormonal, immune, and neural pathways, and any disruption in the balance of gut bacteria can lead to dysbiosis, which contributes to pathogen growth. In this context, we discuss how dysbiosis could contribute to comorbidities that increase susceptibility to SARS-CoV-2. Probiotics and fecal microbiota transplantation have successfully treated infectious and non-infectious inflammatory-related diseases, the most common comorbidities. These treatments could be adjuvant therapies for COVID-19 infection by restoring gut homeostasis and balancing the gut microbiota.

The Impact of Proton Pump Inhibitors on the Efficacy of Immune Checkpoint Inhibitor Combinations in Patients with HBV-Associated Advanced Hepatocellular Carcinoma

Purpose

There is limited research on whether Proton Pump Inhibitors (PPIs) will affect the efficacy of immune checkpoint inhibitors (ICIs) in treating hepatocellular carcinoma (HCC).This study aimed to determine whether PPIs affect the survival outcomes of patients with HBV-associated advanced HCC receiving combination therapy based on ICIs.

Methods

We retrospectively analyzed patients with hepatitis B virus (HBV)-associated advanced HCC who underwent ICIs combination therapy from January 1, 2020, to December 30, 2022. Patients were stratified into PPI and non-PPI groups based on whether they received PPI treatment within 30 days before or after ICIs therapy. Patients' survival and the risk of PPI-associated mortality was assessed. Adverse events were also evaluated.

Results

A total of 183 patients with HBV-associated HCC treated with ICI combination therapy were included. The median survival time (12.5 months vs 13.7 months, P = 0.285) and incidence of adverse events (P = 0.729) did not significantly differ between the PPI and non-PPI groups. Even after propensity score matching, the difference in median overall survival (OS) between the two groups was not significant (10.7 months vs 11.4 months; P = 0.596) and the patient's OS is not significantly related to the dosage of PPI application (P > 0.05).However, according to our subgroup analysis, among HCC patients with a serum HBV DNA concentration ≥ 200 IU/mL, the use of PPIs significantly increased the risk of mortality in patients receiving ICI combination therapy (P = 0.024).

Conclusion

PPIs do not notably influence the survival prognosis of patients receiving ICI combination therapy for HBV-associated advanced HCC. However, among patients with high levels of HBV DNA, PPIs increase the risk of mortality. Therefore, antiviral therapy should be intensified in the patients with HBVDNA > 200 IU/mL. Additionally, PPIs do not impact the incidence of adverse reactions in these patients.

High-pressure Hydrodynamic Injection as a Method of Establishing Hepatitis B Virus Infection in Mice

Among several existing mouse models for hepatitis B virus (HBV) infection, the high-pressure hydrodynamic injection (HDI) method is frequently used in HBV research due to its economic advantages and ease of implementation. The use of the HDI method is influenced by factors such as mouse genetic background, age, sex, and the type of HBV plasmid used. This overview provides a multidimensional analysis and comparison of various factors that influence the effectiveness of the HBV mouse model established through HDI. The goal is to provide a summary of information for researchers who create HBV models in mice.

Viral Liver Disease and Intestinal Gut–Liver Axis

The intestinal microbiota is closely related to liver diseases via the intestinal barrier and bile secretion to the gut. Impairment of the barrier can translocate microbes or their components to the liver where they can contribute to liver damage and fibrosis. The components of the barrier are discussed in this review along with the other elements of the so-called gut–liver axis. This bidirectional relation has been widely studied in alcoholic and non-alcoholic liver disease. However, the involvement of microbiota in the pathogenesis and treatment of viral liver diseases have not been extensively studied, and controversial data have been published. Therefore, we reviewed data regarding the integrity and function of the intestinal barrier and the changes of the intestinal microbioma that contribute to progression of Hepatitis B (HBV) and Hepatitis C (HCV) infection. Their consequences, such as cirrhosis and hepatic encephalopathy, were also discussed in connection with therapeutic interventions such as the effects of antiviral eradication and the use of probiotics that may influence the outcome of liver disease. Profound alterations of the microbioma with significant reduction in microbial diversity and changes in the abundance of both beneficial and pathogenic bacteria were found.

Natural Products in Liver Fibrosis Management: A Five-year Review

Liver fibrosis, characterized by the overproduction of extracellular matrix proteins within liver tissue, poses a rising global health concern. However, no approved antifibrotic drugs are currently available, highlighting the critical need for understanding the molecular mechanisms of liver fibrosis. This knowledge could not only aid in developing therapies but also enable early intervention, enhance disease prediction, and improve our understanding of the interaction between various underlying conditions and the liver. Notably, natural products used in traditional medicine systems worldwide and demonstrating diverse biochemical and pharmacological activities are increasingly recognized for their potential in treating liver fibrosis. This review aims to comprehensively understand liver fibrosis, emphasizing the molecular mechanisms and advancements in exploring natural products' antifibrotic potential over the past five years. It also acknowledges the challenges in their development and seeks to underscore their potency in enhancing patient prognosis and reducing the global burden of liver disease.

Crosstalk between liver macrophages and gut microbiota: An important component of inflammation-associated liver diseases

Hepatic macrophages have been recognized as primary sensors and responders in liver inflammation. By processing host or exogenous biochemical signals, including microbial components and metabolites, through the gut-liver axis, hepatic macrophages can both trigger or regulate inflammatory responses. Crosstalk between hepatic macrophages and gut microbiota is an important component of liver inflammation and related liver diseases, such as acute liver injury (ALI), alcoholic liver disease (ALD), and nonalcoholic fatty liver disease (NAFLD). This review summarizes recent advances in knowledge related to the crosstalk between hepatic macrophages and gut microbiota, including the therapeutic potential of targeting hepatic macrophages as a component of gut microecology in inflammation-associated liver diseases.

Gut microbiota of hepatitis B virus-infected patients in the immune-tolerant and immune-active phases and their implications in metabolite changes

BACKGROUND

The microbes and metabolomics of microbiota dysbiosis in the gut in the different phases of hepatitis B virus (HBV) infection are not fully understood.

AIM

To investigate the specific gut microbiota and metabolites of the immune-tolerant (IT) and immune-active (IA) phases of chronic hepatitis B (CHB).

METHODS

Clinical fecal samples from healthy individuals and patients in the IT and IA phases of HBV infection were collected. Next, non-target metabolomics, bioinformatics, and 16S rDNA sequencing analyses were performed.

RESULTS

A total of 293 different metabolites in 14 phyla, 22 classes, 29 orders, 51 families, and 190 genera were identified. The four phyla of Firmicutes, Bacteroidetes, Actinobacteria, and Proteobacteria were the most abundant, accounting for 99.72%, 99.79%, and 99.55% in the healthy controls, IT-phase patients, and IA-phase patients, respectively. We further identified 16 genera with different richness in the IT phase and IA phase of HBV infection. Of the 134 named metabolites, 57 were upregulated and 77 were downregulated. A total of 101 different metabolic functions were predicted in this study, with 6 metabolic pathways having the highest enrichments, namely carbohydrate metabolism (14.85%), amino acid metabolism (12.87%), lipid metabolism (11.88%), metabolism of cofactors and vitamins (11.88%), xenobiotic biodegradation (9.9%), and metabolism of terpenoids and polyketides (7.92%).

CONCLUSION

These findings provide observational evidence of compositional alterations of the gut microbiome and some related metabolites in patients with IT-phase or IA-phase HBV infection. Further studies should investigate whether microbiota modulation can facilitate the progression of CHB and the cause-effect relationship between the gut microbiota and CHB.

Gut microbiota alteration and modulation in hepatitis B virus-related fibrosis and complications: Molecular mechanisms and therapeutic inventions

Hepatitis B virus (HBV) has posed a threat to public health, mainly resulting in liver damage. With long-term accumulation of extracellular matrix, patients with chronic hepatitis B are at high risk of developing into liver fibrosis and cirrhosis and even life-threatening hepatic carcinoma. The occurrence of complications such as spontaneous bacterial peritonitis and hepatic encephalopathy greatly increases disability and mortality. With deeper understanding of the bidirectional interaction between the liver and the gut (gut-liver axis), there is a growing consensus that the human health closely relates to the gut microbiota. Supported by animal and human studies, the gut microbiota alters as the HBV-related liver fibrosis initials and progresses, characterized as the decrease of the ratio between “good” and “potentially pathogenic” microbes. When the primary disease is controlled via antiviral treatment, the gut microbiota dysfunction tends to be improved. Conversely, the recovery of gut microbiota can promote the regression of liver fibrosis. Therapeutic strategies targeted on gut microbiota (rifaximin, probiotics, engineered probiotics and fecal microbiota transplantation) have been applied to animal models and patients, obtaining satisfactory results.

Helicobacter pylori and Alzheimer's Disease-Related Metabolic Dysfunction: Activation of TLR4/Myd88 Inflammation Pathway from p53 Perspective and a Case Study of Low-Dose Radiation Intervention

Gut dysbiosis is observed in Alzheimer's disease (AD) and is frequently associated with AD-induced metabolic dysfunction. However, the extent and specific underlying molecular mechanisms triggered by alterations of gut microbiota composition and function mediating AD-induced metabolic dysfunction in AD remain incompletely uncovered. Here, we indicate that Helicobacter pylori (H. pylori) is abundant in AD patients with relative metabolic dysfunction. Fecal microbiota transplantation from the AD patients promoted metabolic dysfunction in mice and increased gut permeability. H. pylori increased gut permeability through activation of the TLR4/Myd88 inflammation pathway in a p53-dependent manner, leading to metabolic dysfunction. Moreover, p53 deficiency reduced bile acid concentration, leading to an increased abundance of H. pylori colonization. Overall, these data identify H. pylori as a key promoter of AD-induced metabolic dysfunction.