Multifaceted Interaction Between Hepatitis B Virus Infection and Lipid Metabolism in Hepatocytes: A Potential Target of Antiviral Therapy for Chronic Hepatitis B

Transcriptome Profiling and Viral-Human Interactome Insights Into HBV-Driven Oncogenic Alterations in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the primary form of liver cancer that poses a significant global health concern due to its increasing incidence rates and diverse etiology. Chronic infection induced by hepatitis B virus (HBV) is a prominent etiological factor influencing the development of HCC. Although recent advances in multi-omics approaches have facilitated extensive exploration of HCC molecular characteristics, translating the characteristics of subtypes into clinical applications has been challenging due to parameters like limited sample size and complex classifiers for early detection. In the present study, we performed transcriptomics profiling of HBV-infected HCC patient tissue data to gather comprehensive insights into the intricate molecular mechanisms underlying HBV-associated HCC, specifically, viral protein interactions that influence the expression of oncogenes. The 1059 differentially expressed genes (DEGs) identified across two GEO data sets revealed upregulation of cell cycle and mitosis-related genes, alongside downregulation of genes involved in fatty acid degradation and cytochrome P450 activity. CDK1 and CDC20 which are part of the top cluster and hub gene from interactome analysis were identified as potential markers for HBV-positive HCC through gene expression pattern and overall survival analysis. Additionally, 19 DEGs showing significance in HCC development were identified as interacting partners with HBV proteins. Among them, the interaction of HBsAg with ALB and SHBG and their downregulation correlates to the lower testosterone levels identified in HBV and HCC patients. Together, the study enhances the understanding of the heterogeneity and molecular pathogenesis of HBV-positive HCC.

Circulating citrate as a mediator in the relationship between HMGCR inhibitors and chronic hepatitis B: a Mendelian randomization study

Observational studies have found that HMGCR inhibitors can be used to treat chronic viral hepatitis. In this study, to explore the potential mechanism of HMGCR inhibitors in treating Chronic hepatitis B (CHB), two-sample and two-step Mendelian randomization (MR) were used to investigate the causal relationship between HMGCR inhibitors and the mediating role of circulating metabolites. GWAS data of expression quantitative trait loci eQTLs of HMGCR inhibitors, 168 circulating metabolites, CHB, and myocardial infarction were obtained from the IEUOpenGWAS project. Random effects inverse-variance weighted (IVW) was the main causal analysis method, and the MR-Egger regression method was used as a supplementary analysis method. Cochran's Q test and I2 statistic were used to determine the heterogeneity of SNPs. The intercept terms of the MR-Egger method and MR-PRESSO were used for pleiotropy analysis, and leave-one-out was used for sensitivity analysis. Mediation effect analysis was used to evaluate the mediating role of the circulating metabolites. Genetic variations in the drug target genes of HMGCR inhibitors were associated with a reduced risk of chronic hepatitis B and myocardial infarction (P < 0.05). Eight circulating metabolites had a significant causal relationship with HMGCR inhibitors and CHB. After further calculation of the mediation effect, citrate was used as a mediating variable between HMGCR inhibitors and CHB, with a mediation effect of - 0.015 and a mediation ratio of 9.769%. HMGCR inhibitors can significantly reduce the risk of CHB, and the circulating metabolite citrate may mediate this association. However, this study has certain limitations. The short-term effects of HMGCR inhibitors on CHB could not be assessed, and partial overlap between the GWAS data for HMGCR inhibitors and circulating metabolites may introduce bias in estimating causal effects.

USP21 is involved in the development of chronic hepatitis B by modulating the immune microenvironment

Hepatitis B virus (HBV) infection is a global public health challenge that alters the immune microenvironment of the liver and drives disease progression by triggering chronic inflammation that leads to hepatic cell death through multiple programmed cell death (PCD) modalities. Due to the persistence of covalently closed circular DNA in hepatocytes, there is a lack of curative drugs that can completely eradicate HBV. Therefore, revealing how HBV infection leads to changes in the hepatic immune microenvironment, as well as searching for specific molecular targets, is crucial for controlling the onset and progression of chronic hepatitis B (CHB). In this study, we used the single sample gene set enrichment analysis and CIBERSORT algorithms to assess immune cell infiltration in the livers of CHB patients. With three advanced machine learning algorithms, random forest, least absolute shrinkage and selection operator, and selected support vector machine recursive feature elimination, we identified the PCD signature genes associated with CHB from the candidate genes. We further validated that ubiquitin-specific peptidase 21 could differentiate CHB patients with different natural courses by receiver operating characteristic analysis. These findings enhance our understanding of the mechanisms of HBV infection.

Impact of hepatic steatosis on mortality, hepatocellular carcinoma, end-stage liver disease and HBsAg seroclearance in chronic hepatitis B: a United States cohort study

Background

Steatotic liver disease (SLD) is prevalent among individuals with chronic hepatitis B virus (CHB), yet its impact on clinical outcomes remains controversial.

Methods

We used electronic health record data from 98 US healthcare-delivery systems to compare adults with (CHB-SLD) and without SLD (CHB-wo-SLD) from 2000 to 2024. We applied 1: 1 propensity score matching to balance cohorts by demographic and clinical characteristics. We further performed sensitivity analyses in the presence or absence of cirrhosis. We compared incidence rates (IR) and hazard ratios (HRs) of all-cause mortality, hepatocellular carcinoma (HCC), end-stage liver disease (ESLD) events, and detectable HBsAg and HBeAg as markers of seroclearance.

Results

Among 124,932 individuals with CHB (12.43% CHB-SLD), there were 470,707 person-years of observations (median follow-up 2.95 years). Compared with CHB, individuals with CHB-SLD had a lower mortality risk (HR 0.44, 95% CI 0.40-0.48). Fibrosis risk was higher among those with CHB-SLD (vs CHB-wo-SLD) (HR 1.93, 95% CI 1.71-2.19); however, cirrhosis risk was comparable (HR 1.06, 95% CI 0.96-1.18) between cohorts, while HCC risk was lower in the CHB-SLD cohort (HR 0.83, 95% CI 0.70-0.96). The CHB-SLD cohort also had significantly reduced risks of ESLD events, including ascites, spontaneous bacterial peritonitis, variceal bleeding, hepatic encephalopathy, and hepatorenal syndrome (all p < 0.001). Additionally, detectable HBsAg and HBeAg IRs and HRs were lower among CHB-SLD compared to the CHB-wo-SLD cohort: 26.83 vs. 31.96 per 1,000 person-years (HR 0.80, 95% CI 0.73-0.87) and 8.52 vs. 11.36 per 1,000 person-years (HR 0.74, 95% CI 0.65-0.85), respectively. Sensitivity analyses stratified by cirrhosis status supported these findings.

Conclusion

CHB-SLD status was associated with more favorable outcomes, highlighting the complexity of CHB and SLD interactions.

MiR-451a attenuates hepatic steatosis and hepatitis C virus replication by targeting glycerol kinase

BACKGROUND

Lipotoxicity is one of the causes for the progression of fatty liver in chronic hepatitis (CH) towards end-stage liver diseases. The role of miRNAs in the signalling pathways of lipid metabolism has been studied, but their direct targets in this pathway have not been identified yet. Here, we have characterized a downregulated miRNA in CH namely miR-451a, which has a direct impact on the lipid metabolism pathway.

METHODS

Liver tissue samples and blood were collected from CHC/CHB patients and normal individuals. Huh7 and SNU449 cell lines were used for in vitro assays. Expressions of miRNA/mRNAs and proteins were confirmed by qRT-PCR and immuno-blot analysis. Oil Red O staining, Colorimetric, and Fluorometric assay kit were used to quantify triglyceride (TG) and cholesterol from tissue and serum, respectively. Target prediction and pathway analysis were performed using Targetscan, miRWalk, and DAVID respectively. 3'UTR-Luciferase assay and Co-immuno-precipitation were conducted to determine direct interaction between miRNA-mRNA and protein-protein, respectively. Unpaired two-tailed Student's t-test and Mann-Whitney test were employed as required using GraphPad prism. P < 0.05 was considered as significant.

RESULTS

The miRNA, miR-451a was selected as one of the downregulated miRNAs in progressive liver disease stages of CHC and CHB. Target identification and pathway analysis of this miRNA revealed that lipid metabolism pathway gene, glycerol kinase (GK), could be the target of this miRNA. Subsequent 3'UTR Luciferase assay and immuno-blot analysis confirmed the binding of miR-451a to GK. Though both hepatitis viruses, HCV and HBV, could alter the lipid metabolism pathways, intracellular TG and cholesterol content were observed to be significantly higher upon HCV infection only. It also suppressed the expression of miR-451a, resulting in overshooting of GK expression. GK interacted positively with the transcription factor SREBP1, which led to overexpression of Fatty acid synthase, Acetyl- CoA Carboxylase, and Stearoyl-CoA desaturase. As a result, intracellular fatty acids, TG, and cholesterol synthesis and accumulation heightened but trafficking dropped, resulting in hypo-cholesterolemia in blood. While, restoration of miR-451a impeded lipid accumulation, reduced steatohepatitis and suppressed HCV replication as well.

CONCLUSION

These findings suggest that the alteration in the hepatic lipid profile upon HCV/HBV infection is attributed to the downregulation of miR-451a, which has the potential to restrict the expression of GK and SREBP1 in the TG biosynthesis pathway, implying that supplementation of miR-451a may be a potential therapeutic strategy for impeding CHC.

Small hepatitis B virus surface antigen (SHBs) induces dyslipidemia by suppressing apolipoprotein-AII expression through ER stress-mediated modulation of HNF4α and C/EBPγ

Persistent infection with hepatitis B virus (HBV) often leads to disruptions in lipid metabolism. Apolipoprotein AII (apoAII) plays a crucial role in lipid metabolism and is implicated in various metabolic disorders. However, whether HBV could regulate apoAII and contribute to HBV-related dyslipidemia and the underlying mechanism remain unclear. This study revealed significant reductions in apoAII expression in HBV-expressing cell lines, the serum, and liver tissues of HBV-transgenic mice. The impact of HBV on apoAII is related to small hepatitis B virus surface antigen (SHBs). Overexpression of SHBs decreased apoAII levels in SHBs-expressing hepatoma cells, transgenic mice, and the serum of HBV-infected patients, whereas suppression of SHBs increased apoAII expression. Mechanistic investigations demonstrated that SHBs repressed the apoAII promoter activity through a HNF4α- and C/EBPγ-dependent manner; SHBs simultaneously upregulated C/EBPγ and downregulated HNF4α by inhibiting the PI3K/AKT signaling pathway through activating endoplasmic reticulum (ER) stress. Serum lipid profile assessments revealed notable decreases in high-density lipoprotein cholesterol (HDL-C), total cholesterol (TC), and triglycerides (TG) in SHBs-transgenic mice compared to control mice. However, concurrent overexpression of apoAII in these mice effectively counteracted these reductions in lipid levels. In HBV patients, SHBs levels were negatively correlated with serum levels of HDL-C, LDL-C, TC, and TG, whereas apoAII levels positively correlated with lipid content. This study underscores that SHBs contributes to dyslipidemia by suppressing the PI3K/AKT pathway via inducing ER stress, leading to altered expression of HNF4α and C/EBPγ, and subsequently reducing apoAII expression.IMPORTANCEThe significance of this study lies in its comprehensive examination of how the hepatitis B virus (HBV), specifically through its small hepatitis B virus surface antigen (SHBs), impacts lipid metabolism-a key aspect often disrupted by chronic HBV infection. By elucidating the role of SHBs in regulating apolipoprotein AII (apoAII), a critical player in lipid processes and associated metabolic disorders, this research provides insights into the molecular pathways contributing to HBV-related dyslipidemia. Discovering that SHBs downregulates apoAII through mechanisms involving the repression of the apoAII promoter via HNF4α and C/EBPγ, and the modulation of the PI3K/AKT signaling pathway via endoplasmic reticulum (ER) stress, adds critical knowledge to HBV pathogenesis. The research also shows an inverse correlation between SHBs expression and key lipid markers in HBV-infected individuals, suggesting that apoAII overexpression could counteract the lipid-altering effects of SHBs, offering new avenues for understanding and managing the metabolic implications of HBV infection.

Long-term HBV infection of engineered cultures of induced pluripotent stem cell-derived hepatocytes

BACKGROUND

HBV infects ~257 million people and can cause hepatocellular carcinoma. Since current drugs are not curative, novel therapies are needed. HBV infects chimpanzee and human livers. However, chimpanzee studies are severely restricted and cost-prohibitive, while transgenic/chimeric mouse models that circumvent the species barrier lack natural HBV infection and disease progression. Thus, in vitro human models of HBV infection are useful in addressing the above limitations. Induced pluripotent stem cell-derived hepatocyte-like cells mitigate the supply limitations of primary human hepatocytes and the abnormal proliferation/functions of hepatoma cell lines. However, variable infection across donors, deficient drug metabolism capacity, and/or low throughput limit iHep utility for drug development.

METHODS

We developed an optimal pipeline using combinations of small molecules, Janus kinase inhibitor, and 3',5'-cAMP to infect iHep-containing micropatterned co-cultures (iMPCC) with stromal fibroblasts within 96-well plates with serum-derived HBV and cell culture-derived HBV (cHBV). Polyethylene glycol was necessary for cell-derived HBV but not for serum-derived HBV infection.

RESULTS

Unlike iHep monocultures, iMPCCs created from 3 iHep donors could sustain HBV infection for 2+ weeks. Infected iMPCCs maintained high levels of differentiated functions, including drug metabolism capacity. HBV antigen secretion and gene expression patterns in infected iMPCCs in pathways such as fatty acid metabolism and cholesterol biosynthesis were comparable to primary human hepatocyte-MPCCs. Furthermore, iMPCCs could help elucidate the effects of interferons and direct-acting antiviral drugs on the HBV lifecycle and any hepatotoxicity; iMPCC response to compounds was similar to primary human hepatocyte-MPCCs.

CONCLUSIONS

The iMPCC platform can enable the development of safe and efficacious drugs against HBV and ultimately help elucidate genotype-phenotype relationships in HBV pathogenesis.

Serum ApoB/ApoA1 ratio in patients with CHB and the occurrence of HBV related cirrhosis and HBV related hepatocellular carcinoma

Clinical research has suggested that chronic HBV infection exerts a certain effect on the occurrence of cardiovascular disease by regulating cholesterol metabolism in liver cells. High serum apolipoprotein B/apolipoprotein A1 (ApoB/ApoA1) ratio plays a certain role in the above regulation, and it serves as a risk factor for cardiovascular disease. However, whether the ApoB/ApoA1 ratio is correlated with chronic HBV infection and its disease progression remains unclear. In accordance with the inclusion and exclusion criteria, all 378 participants administrated at Renmin Hospital of Wuhan University from March 2021 to March 2022, fell into Healthy Control (HC) group (50 participants), Hepatocellular carcinoma (HCC) group (107 patients), liver cirrhosis (LC) group (64 patients), chronic hepatitis B (CHB) group (62 patients), chronic hepatitis C (CHC) group (46 patients) and Hepatitis E Virus (HEV) group (49 patients). Serum ApoA1 and ApoB concentrations were measured at admission, and the ApoB/ApoA1 ratio was determined. The levels of laboratory parameters in the respective group were compared and ApoB/ApoA1 ratios in HCC patients and LC patients with different severity were further analyzed. ROC curves were plotted to analyze the early diagnostic ability of ApoB/ApoA1 ratio for HBV-associated HCC. Logistic regression and restricted cubic spline analysis were used to explore the correlation between ApoB/ApoA1 ratio and LC and HCC risk. A comparison was drawn in terms of ApoB/ApoA1 ratio between the groups, and the result was expressed in descending sequence: HEV group > CHB group > LC group > HCC group > CHC group > HC group, early-stage HCC < middle-stage HCC < advanced-stage HCC, Class A LC < Class B LC < Class C LC. Serum ApoB/ApoA1 ratio combined diagnosis with AFP exhibited the capability of increasing the detection efficacy and specificity of AFP for HCC and AFP-negative HCC. The incidence of LC and HCC in the respective logistic regression model showed a negative correlation with the serum ApoB/ApoA1 ratio in CHB patients (P < 0.05). After all confounding factors covered in this study were regulated, the result of the restricted cubic spline analysis suggested that in a certain range, serum ApoB/ApoA1 ratio showed an inverse correlation with the prevalence of LC or HCC in CHB patients. Serum ApoB/ApoA1 ratio in CHB patients may be conducive to identifying high-risk patients for HCC or LC, such that LC and HCC can be early diagnosed and treated.

The Association Between Weight Loss and Hepatitis B Surface Antigen Seroclearence in Chronic Hepatitis B Patients

Background: In chronic hepatitis B (CHB) patients, hepatitis B surface antigen (HBsAg) seroclearance is the main target of therapy and is rarely observed. Objectives: This study aimed to investigate the factors affecting HBsAg loss by focusing especially on the relationship between weight loss and HBsAg loss. Methods: This study was designed retrospectively to assess HBsAg status and clinical and laboratory findings in CHB patients, as well as cross-sectionally to evaluate lifestyle factors. A total of 5600 hepatitis B (HB) infection patients who were treated or followed between 2008 and 2020 were evaluated retrospectively. In the HBsAg loss group, 94 CHB patients were examined based on exclusion criteria, and 95 patients without HBsAg loss were matched as controls. Patient data and laboratory findings were retrieved from patient files. All participants were surveyed using a questionnaire developed by the authors, which inquired about the lifestyle characteristics of CHB patients. The questionnaire covered topics such as the use of herbal products, coffee consumption, medication history, antiviral treatment, concurrent diseases, weight changes, and patient demographics. Statistical analysis was performed using SPSS version 25.0. The Student's t-test was used to compare quantitative variables, while the chi-square test was used for categorical variables. A paired samples t-test was used to compare dependent samples. The statistical significance level was set at a p value less than 0.05. Results: The basal mean hepatitis B virus (HBV) DNA level was significantly lower in the HBsAg loss group (P < 0.001). The prevalence of hyperlipidemia comorbidity (P = 0.008) and moderate/severe hepatosteatosis (P < 0.05) was significantly higher in the HBsAg loss group compared to the non-HBsAg loss group. Prior to HBsAg loss, 44 (47%) patients in the HBsAg loss group experienced weight loss, whereas only 22 (23%) patients in the non-HBsAg group had a history of weight loss (P < 0.001). Conversely, the incidence of weight gain was significantly lower in the HBsAg loss group (P = 0.001). A paired samples t-test was conducted to compare the baseline and last period body mass index (BMI) means of the HBsAg loss group, revealing a statistically significant decrease in mean BMI in the last period (P < 0.001). Conclusions: Weight loss was significantly associated with HBsAg seroclearance in patients with CHB infection. Conversely, weight gain was associated with HBsAg persistence.

NAMPT promotes the malignant progression of HBV-associated hepatocellular carcinoma through activation of SREBP1-mediated lipogenesis

Metabolic reprogramming is a hallmark of cancer. The nicotinamide phosphoribosyltransferase (NAMPT)-mediated salvage pathway maintains sufficient cellular NAD levels and is required for tumorigenesis and development. However, the molecular mechanism by which NAMPT contributes to HBV-associated hepatocellular carcinoma (HCC) remains not fully understood. In the present study, our results showed that NAMPT protein was obviously upregulated in HBV-positive HCC tissues compared with HBV-negative HCC tissues. NAMPT was positively associated with aggressive HCC phenotypes and poor prognosis in HBV-positive HCC patients. NAMPT overexpression strengthened the proliferative, migratory, and invasive capacities of HBV-associated HCC cells, while NAMPT-insufficient HCC cells exhibited decreased growth and mobility. Mechanistically, we demonstrated that NAMPT activated SREBP1 (sterol regulatory element-binding protein 1) by increasing the expression and nuclear translocation of SREBP1, leading to the transcription of SREBP1 downstream lipogenesis-related genes and the production of intracellular lipids and cholesterol. Altogether, our data uncovered an important molecular mechanism by which NAMPT promoted HBV-induced HCC progression through the activation of SREBP1-triggered lipid metabolism reprogramming and suggested NAMPT as a promising prognostic biomarker and therapeutic target for HBV-associated HCC patients.

The novel mechanism facilitating chronic hepatitis B infection: immunometabolism and epigenetic modification reprogramming

Hepatitis B Virus (HBV) infections pose a global public health challenge. Despite extensive research on this disease, the intricate mechanisms underlying persistent HBV infection require further in-depth elucidation. Recent studies have revealed the pivotal roles of immunometabolism and epigenetic reprogramming in chronic HBV infection. Immunometabolism have identified as the process, which link cell metabolic status with innate immunity functions in response to HBV infection, ultimately contributing to the immune system's inability to resolve Chronic Hepatitis B (CHB). Within hepatocytes, HBV replication leads to a stable viral covalently closed circular DNA (cccDNA) minichromosome located in the nucleus, and epigenetic modifications in cccDNA enable persistence of infection. Additionally, the accumulation or depletion of metabolites not only directly affects the function and homeostasis of immune cells but also serves as a substrate for regulating epigenetic modifications, subsequently influencing the expression of antiviral immune genes and facilitating the occurrence of sustained HBV infection. The interaction between immunometabolism and epigenetic modifications has led to a new research field, known as metabolic epigenomics, which may form a mutually reinforcing relationship with CHB. Herein, we review the recent studies on immunometabolism and epigenetic reprogramming in CHB infection and discuss the potential mechanisms of persistent HBV infection. A deeper understanding of these mechanisms will offer novel insights and targets for intervention strategies against chronic HBV infection, thereby providing new hope for the treatment of related diseases.

Chronic Hepatitis B Virus Infection and Risk of Stroke Types: A Prospective Cohort Study of 500 000 Chinese Adults

BACKGROUND

Stroke is a leading cause of mortality and permanent disability in China, with large and unexplained geographic variations in rates of different stroke types. Chronic hepatitis B virus infection is prevalent among Chinese adults and may play a role in stroke cause.

METHODS

The prospective China Kadoorie Biobank included >500 000 adults aged 30 to 79 years who were recruited from 10 (5 urban and 5 rural) geographically diverse areas of China from 2004 to 2008, with determination of hepatitis B surface antigen (HBsAg) positivity at baseline. During 11 years of follow-up, a total of 59 117 incident stroke cases occurred, including 11 318 intracerebral hemorrhage (ICH), 49 971 ischemic stroke, 995 subarachnoid hemorrhage, and 3036 other/unspecified stroke. Cox regression models were used to estimate adjusted hazard ratios (HRs) for risk of stroke types associated with HBsAg positivity. In a subset of 17 833 participants, liver enzymes and lipids levels were measured and compared by HBsAg status.

RESULTS

Overall, 3.0% of participants were positive for HBsAg. HBsAg positivity was associated with an increased risk of ICH (adjusted HR, 1.29 [95% CI, 1.16-1.44]), similarly for fatal (n=5982; adjusted HR, 1.36 [95% CI, 1.16-1.59]) and nonfatal (n=5336; adjusted HR, 1.23 [95% CI, 1.06-1.44]) ICH. There were no significant associations of HBsAg positivity with risks of ischemic stroke (adjusted HR, 0.97 [95% CI, 0.92-1.03]), subarachnoid hemorrhage (adjusted HR, 0.87 [95% CI, 0.57-1.33]), or other/unspecified stroke (adjusted HR, 1.12 [95% CI, 0.89-1.42]). Compared with HBsAg-negative counterparts, HBsAg-positive individuals had lower lipid and albumin levels and higher liver enzyme levels. After adjustment for liver enzymes and albumin, the association with ICH from HBsAg positivity attenuated to 1.15 (0.90-1.48), suggesting possible mediation by abnormal liver function.

CONCLUSIONS

Among Chinese adults, chronic hepatitis B virus infection is associated with an increased risk of ICH but not other stroke types, which may be mediated through liver dysfunction and altered lipid metabolism.

Histomolecular characterisation of hepatitis B virus induced liver cancer

Hepatitis B virus (HBV)-associated liver cancer is the third most prevalent cancer-related cause of death worldwide. Different studies have been done on the histomolecular analysis of HBV induced-liver cancer including epigenetics which are dynamic molecular mechanisms to control gene expression without altering the host deoxyribonucleic acid, genomics characterise the integration of the viral genome with host genome, proteomics characterise how gene modifies and results overexpression of proteins, glycoproteomics discover different glyco-biomarker candidates and show glycosylation in malignant hepatocytes, metabolomics characterise how HBV impairs a variety of metabolic functions during hepatocyte immortalisation, exosomes characterise immortalised liver cells in terms of their differentiation and proliferation, and autophagy plays a role in the development of hepatocarcinogenesis linked to HBV infection.

Comparisons of Insulin Resistance- and Steatosis-Based Scores in Monitoring Metabolic Associated Fatty Liver Disease Treatment Response

BACKGROUND

Quantitative measurements of liver fat contents (LFCs) by magnetic resonance imaging derived-proton density fat fraction (MRI-PDFF) are accurate but limited by availability, convenience, and expense in the surveillance of metabolic associated fatty liver (MAFLD). Insulin resistance (IR) and steatosis-associated serum indices are useful in screening for MAFLD, but their value in monitoring MAFLD with or without chronic hepatitis B virus (CHB) infection remains unclear and we aimed to evaluate these scores in predicting changes in LFC.

METHODS

We conducted a prospective study between January 2015 and December 2021 with 620 consecutive participants with MAFLD (212 participants with CHB) who received a 24-week lifestyle intervention. The homeostasis model assessment of IR (HOMA-IR), HOMA2 index, glucose-insulin ratio, quantitative insulin sensitivity check index, fasting insulin resistance index, fatty liver index (FLI), hepatic steatosis index (HSI), liver fat score (LFS), visceral adiposity index, and triglycerides * glucose were calculated.

RESULTS

When using endpoints such as LFS improvements of ≥5% or 10% or escalations of ≥5%, LFS had the highest area under the curve (AUC) values at all endpoints for MAFLD alone (0.756, 95% CI: 0.707-0.805; 0.761, 95% CI: 0.705-0.818; 0.807, 95% CI: 0.713-0.901, all p < 0.05, respectively). With CHB, the FLI (AUC = 0.750) and HIS (AUC = 0.770) exhibited the highest AUCs between the former two outcomes, respectively, but no score could predict LFC escalation of ≥5%.

CONCLUSION

Among IR and steatosis scores, changes in LFC through lifestyle interventions can be captured with LFS possessing moderate precision but not in those with CHB.

Unravelling the Interplay: Exploring the Influence of Previous Hepatitis B Virus, Hepatitis A Virus, and Hepatitis E Virus Infections on Non-alcoholic Fatty Liver Disease

The intricate interplay between viral infections and non-alcoholic fatty liver disease (NAFLD) presents a fascinating and clinically significant intersection of virology and hepatology. This review article delves into the complex relationship between hepatitis B virus (HBV), hepatitis A virus (HAV), hepatitis E virus (HEV), and NAFLD. It outlines the shared mechanisms linking viral infections to NAFLD development, including their effects on lipid metabolism, immune responses, inflammation, and gut microbiota. The clinical implications of this interplay are explored, including challenges in diagnosis and management and potential therapeutic strategies. The review emphasises the need for a comprehensive understanding of these interactions as they impact disease progression, risk stratification, and treatment decisions. Furthermore, it highlights the importance of integrated approaches and personalised treatment paradigms for optimising patient care. As we navigate this intricate crossroads, the insights gained can reshape our understanding of liver health and contribute to more effective strategies for managing viral infections and NAFLD.

Oncogenic viruses and host lipid metabolism: a new perspective

As noncellular organisms, viruses do not have their own metabolism and rely on the metabolism of host cells to provide energy and metabolic substances for their life cycles. Increasing evidence suggests that host cells infected with oncogenic viruses have dramatically altered metabolic requirements and that oncogenic viruses produce substances used for viral replication and virion production by altering host cell metabolism. We focused on the processes by which oncogenic viruses manipulate host lipid metabolism and the lipid metabolism disorders that occur in oncogenic virus-associated diseases. A deeper understanding of viral infections that cause changes in host lipid metabolism could help with the development of new antiviral agents as well as potential new therapeutic targets.

Systematic analysis on the mechanism of Zhizi-Bopi decoction against hepatitis B via network pharmacology and molecular docking

PURPOSE

Zhizi-Bopi decoction (ZZBPD) is a classic herbal formula with wide clinical applications in treating liver diseases including hepatitis B. However, the mechanism needs to be elucidated.

METHODS

Chemical components of ZZBPD were identified by ultra-high-performance liquid chromatography coupled with time-of-flight mass spectrometry (UHPLC-TOF-MS). Then we used network pharmacology to identify their potential targets. Network construction, coupled with protein-protein interaction and enrichment analysis was used to identify representative components and core targets. Finally, molecular docking simulation was conducted to further refine the drug-target interaction.

RESULTS

One hundred and forty-eight active compounds were identified in ZZBPD, targeting 779 genes/proteins, among which 174 were related to hepatitis B. ZZBPD mainly influences the progression of hepatitis B through the hepatitis B pathway (hsa05161) via core anti-HBV targets (AKT1, PIK3CA, PIK3R1, SRC, TNF, MAPK1, and MAPK3). Enrichment analysis indicated that ZZBPD can also potentially regulate lipid metabolism and enhance cell survival. Molecular docking suggested that the representative active compounds can bind to the core anti-HBV targets with high affinity.

CONCLUSION

The potential molecular mechanisms of ZZBPD in hepatitis B treatment were identified using network pharmacology and molecular docking approaches. The results serve as an important basis for the modernization of ZZBPD.

Many Ways to Communicate-Crosstalk between the HBV-Infected Cell and Its Environment

Chronic infection with the hepatitis B virus (HBV) affects an estimated 257 million people worldwide and can lead to liver diseases such as cirrhosis and liver cancer. Viral replication is generally considered not to be cytopathic, and although some HBV proteins may have direct carcinogenic effects, the majority of HBV infection-related disease is related to chronic inflammation resulting from disrupted antiviral responses and aberrant innate immune reactions. Like all cells, healthy and HBV-infected cells communicate with each other, as well as with other cell types, such as innate and adaptive immune cells. They do so by both interacting directly and by secreting factors into their environment. Such factors may be small molecules, such as metabolites, single viral proteins or host proteins, but can also be more complex, such as virions, protein complexes, and extracellular vesicles. The latter are small, membrane-enclosed vesicles that are exchanged between cells, and have recently gained a lot of attention for their potential to mediate complex communication and their potential for therapeutic repurposing. Here, we review how HBV infection affects the communication between HBV-infected cells and cells in their environment. We discuss the impact of these interactions on viral persistence in chronic infection, as well as their relation to HBV infection-related pathology.

Sac1 phosphatidylinositol 4-phosphate phosphatase is a novel host cell factor regulating hepatitis B virus particles assembly and release

The life-cycle of the Hepatitis B Virus (HBV), an enveloped DNA virus affecting the lives of more than 296 million chronicallyinfected people, is tightly dependent on the lipid metabolism of the host cell. Fatty acids and cholesterol are among the lipid factors with documented roles in regulating HBV replication and infection, respectively, but little is known about the phosphoinositide metabolism in these processes. In this study, we investigated the role of Sac1, a highly conserved phosphatidylinositol-4-phosphate (PI4P) phosphatase, with essential functions in phospholipid metabolism, in HBV assembly, and release. PI4P is one of the most abundant cellular phosphoinositide with complex functions at the level of the secretory pathway. Owing to the highly specific phosphatase activity toward PI4P, Sac1 controls the levels and restricts the localization of this lipid particularly at the trans-Golgi network, where it regulates sphingolipid synthesis, proteins sorting, and vesicles budding, by recruiting specific adaptor proteins. As a complete loss of Sac1 function compromises cell viability, in this work, we first developed and characterized several HBV replication-permissive cellular models with a moderate, transient, or stable downregulation of Sac1 expression. Our results show that Sac1 depletion in hepatic cells results in increased levels and redistribution of intracellular PI4P pools and impaired trafficking of the HBV envelope proteins to the endosomal vesicular network. Importantly, virus envelopment and release from these cells are significantly inhibited, revealing novel roles for Sac1, as a key host cell factor regulating morphogenesis of a DNA virus.

What role for cellular metabolism in the control of hepatitis viruses?

Hepatitis B, C and D viruses (HBV, HCV, HDV, respectively) specifically infect human hepatocytes and often establish chronic viral infections of the liver, thus escaping antiviral immunity for years. Like other viruses, hepatitis viruses rely on the cellular machinery to meet their energy and metabolite requirements for replication. Although this was initially considered passive parasitism, studies have shown that hepatitis viruses actively rewire cellular metabolism through molecular interactions with specific enzymes such as glucokinase, the first rate-limiting enzyme of glycolysis. As part of research efforts in the field of immunometabolism, it has also been shown that metabolic changes induced by viruses could have a direct impact on the innate antiviral response. Conversely, detection of viral components by innate immunity receptors not only triggers the activation of the antiviral defense but also induces in-depth metabolic reprogramming that is essential to support immunological functions. Altogether, these complex triangular interactions between viral components, innate immunity and hepatocyte metabolism may explain why chronic hepatitis infections progressively lead to liver inflammation and progression to cirrhosis, fibrosis and hepatocellular carcinoma (HCC). In this manuscript, we first present a global overview of known connections between the innate antiviral response and cellular metabolism. We then report known molecular mechanisms by which hepatitis viruses interfere with cellular metabolism in hepatocytes and discuss potential consequences on the innate immune response. Finally, we present evidence that drugs targeting hepatocyte metabolism could be used as an innovative strategy not only to deprive viruses of key metabolites, but also to restore the innate antiviral response that is necessary to clear infection.

Emerging role of mitochondria in response to HBV infection

Hepatitis B is a major global health problem that potentially life‐threatening liver infection caused by the hepatitis B virus (HBV), which can lead to death due to liver cirrhosis and hepatocellular carcinoma (HCC). A considerable of research has demonstrated that mitochondrial dysfunction exists in patients with HBV infection, indicating that there is clinical relation between HBV infection and mitochondrial alterations. To explore the complex interplay between the functions of mitochondria and HBV infection in greater depth, we systematically summarized these mitochondrial alterations due to HBV infection in recent years. The liver is the central organ of metabolism that is a mitochondria‐rich tissue and represents strong defense and regeneration capabilities in the body. Infested cells and their microenvironment must upregulate energy production for proliferation, growth, and effector functions to restrain the damage imposed by HBV. The changes in metabolic pathways caused by HBV infection are nothing more than those in the cytoplasm and mitochondria. Thus, this article brings into focus the effects of novel reprogramming of inner and outer mitochondria on HBV infection and then derives novel insights and new approaches for HBV diagnosis and therapy.

Targeting lipid biosynthesis pathways for hepatitis B virus cure

Chronic hepatitis B virus (HBV) infection is characterized by the presence of high circulating levels of non-infectious lipoprotein-like HBV surface antigen (HBsAg) particles thought to contribute to chronic immune dysfunction in patients. Lipid and metabolomic analysis of humanized livers from immunodeficient chimeric mice (uPA/SCID) revealed that HBV infection dysregulates several lipid metabolic pathways. Small molecule inhibitors of lipid biosynthetic pathway enzymes acetyl-CoA carboxylase (ACC), fatty acid synthase, and subtilisin kexin isozyme-1/site-1 protease in HBV-infected HepG2-NTCP cells demonstrated potent and selective reduction of extracellular HBsAg. However, a liver-targeted ACC inhibitor did not show antiviral activity in HBV-infected liver chimeric mice, despite evidence of on-target engagement. Our study suggests that while HBsAg production may be dependent on hepatic de novo lipogenesis in vitro, this may be overcome by extrahepatic sources (such as lipolysis or diet) in vivo. Thus, a combination of agents targeting more than one lipid metabolic pathway may be necessary to reduce HBsAg levels in patients with chronic HBV infection.

Interplay between Lipid Metabolism, Lipid Droplets, and DNA Virus Infections

Lipid droplets (LDs) are cellular organelles rich in neutral lipids such as triglycerides and cholesterol esters that are coated by a phospholipid monolayer and associated proteins. LDs are known to play important roles in the storage and availability of lipids in the cell and to serve as a source of energy reserve for the cell. However, these structures have also been related to oxidative stress, reticular stress responses, and reduced antigen presentation to T cells. Importantly, LDs are also known to modulate viral infection by participating in virus replication and assembly. Here, we review and discuss the interplay between neutral lipid metabolism and LDs in the replication cycle of different DNA viruses, identifying potentially new molecular targets for the treatment of viral infections.

Seroprevalence, risk factors and impact of dengue fever/hepatitis B coinfection on liver function parameters in Cameroonian patients

Introduction

Dengue and hepatitis B are viral infections endemic to tropical areas with liver consequences. However, coinfection cases have been poorly documented worldwide and especially on the African continent. This study aimed at analysing the seroepidemiology of dengue-hepatitis B co-infection in patients recruited at the Regional Hospital of Ngaoundere (Cameroon).

Material and methods

A cross-sectional study was conducted among 225 patients, aged 15-55 years, enrolled at the Laboratory service of Ngaoundere Regional Hospital from 25 September to 10 December 2021. HBsAg and dengue infection were diagnosed using the serological rapid tests. Part of the blood samples was used to quantify lipid profile and liver function parameters.

Results

Of the 225 patients recruited, 22.22% (50) tested positive for hepatitis B and 18.18% (38/202) were positive for dengue fever, with a dengue-hepatitis B coinfection rate of 4.95% (10/202). Coinfected patients were not significantly associated with liver injury compared to monoinfected patients. However, they displayed a higher risk of presenting abnormal γ-glutamyltransferase (γ-GT) (RR = 1.74, 90% vs. 51.51%) and alanine aminotransferase (ALT) values (RR = 1.52, 60% vs. 39.39%) compared to the monoinfected group. Also, there was no difference in total and direct bilirubin between patient groups. The mean triglyceride and low-density lipoprotein (LDL) cholesterol levels and coronary heart index values were higher in the coinfected group than in the monoinfected group, but without significance.

Conclusions

Taken altogether, these findings suggest that the presence of hepatitis B in dengue patients may slightly affect the liver's metabolic functions. Clinical surveillance of this coinfection is therefore required to avoid further liver complications.

Metabolic Regulation of Hepatitis B Virus Infection in HBV-Transgenic Mice

Hepatitis B virus (HBV) infection is a worldwide health burden. Metabolomics analysis has revealed HBV-induced metabolism dysregulation in liver tissues and hepatocytes. However, as an infectious disease, the tissue-specific landscape of metabolic profiles of HBV infection remains unclear. To fill this gap, we applied untargeted nuclear magnetic resonance (NMR) metabolomic analysis of the heart, liver, spleen, lung, kidney, pancreas, and intestine (duodenum, jejunum, ileum) in HBV-transgenic mice and their wild-type littermates. Strikingly, we found systemic metabolic alterations induced by HBV in liver and extrahepatic organs. Significant changes in metabolites have been observed in most tissues of HBV-transgenic mice, except for ileum. The metabolic changes may provide novel therapeutic targets for the treatment of HBV infection. Moreover, tissue-specific metabolic profiles could speed up the study of HBV induced systemic metabolic reprogramming, which could help follow the progression of HBV infection and explain the underlying pathogenesis.

Metabolic Disorders in Patients with Chronic Hepatitis B Virus Infection: Coffee as a Panacea? (ANRS CO22 Hepather Cohort)

People living with chronic hepatitis B virus (HBV) infection are at high risk of liver disease progression, which is positively associated with metabolic disorders, but inversely associated with dyslipidemia. Diet, including dietary antioxidants, is a lever of metabolic disorder management. In particular, elevated coffee consumption is associated with different metabolic outcomes in the general population. We aimed to test whether such associations occur in HBV-infected people. Based on cross-sectional data from the ANRS CO22 Hepather cohort, we performed logistic regression models with (i) dyslipidemia, (ii) hypertension, and (iii) diabetes as outcomes, and with demographic, clinical, and socio-behavioral (including coffee consumption) data as explanatory variables. Among 4746 HBV-infected patients, drinking ≥3 cups of coffee per day was associated with a higher risk of dyslipidemia (adjusted odds ratio [95% confidence interval] 1.49 [1.10–2.00], p = 0.009) and a lower risk of hypertension (0.64 [0.50–0.82], p = 0.001). It was not associated with diabetes. Elevated coffee consumption was associated with a higher risk of dyslipidemia and a lower risk of hypertension in HBV-infected patients, two effects expected to be associated with favorable clinical outcomes. Further studies should test whether such metabolic benefits translate into reduced mortality risk in this population.

SGIV Induced and Exploited Cellular De Novo Fatty Acid Synthesis for Virus Entry and Replication

Considerable attention has been paid to the roles of lipid metabolism in virus infection due to its regulatory effects on virus replication and host antiviral immune response. However, few literature has focused on whether lipid metabolism is involved in the life cycle of lower vertebrate viruses. Singapore grouper iridovirus (SGIV) is the causative aquatic virus that extensively causes fry and adult groupers death. Here, the potential roles of cellular de novo fatty acid synthesis in SGIV infection was investigated. SGIV infection not only increased the expression levels of key enzymes in fatty acid synthesis in vivo/vitro, including acetyl-Coenzyme A carboxylase alpha (ACC1), fatty acid synthase (FASN), medium-chain acyl-CoA dehydrogenase (MCAD), adipose triglyceride lipase (ATGL), lipoprotein lipase (LPL) and sterol regulatory element-binding protein-1 (SREBP1), but it also induced the formation of lipid droplets (LDs), suggesting that SGIV altered de novo fatty acid synthesis in host cells. Using the inhibitor and specific siRNA of ACC1 and FASN, we found that fatty acid synthesis was essential for SGIV replication, evidenced by their inhibitory effects on CPE progression, viral gene transcription, protein expression and virus production. Moreover, the inhibitor of fatty acid β-oxidation could also reduce SGIV replication. Inhibition of fatty acid synthesis but not β-oxidation markedly blocked virus entry during the life cycle of SGIV infection. In addition, we also found that inhibition of ACC1 and FASN increased the IFN immune and inflammatory response during SGIV infection. Together, our data demonstrated that SGIV infection in vitro regulated host lipid metabolism and, in that process, cellular fatty acid synthesis might exert crucial roles during SGIV infection via regulating virus entry and host immune response.

PPAR Ligands Induce Antiviral Effects Targeting Perturbed Lipid Metabolism during SARS-CoV-2, HCV, and HCMV Infection

Simple Summary

The current coronavirus disease 2019 pandemic turned the attention of researchers to developing novel strategies to counteract virus infections. Despite several antiviral drugs being commercially available, there is an urgent need to identify novel molecules efficacious against viral infections that act through different mechanisms of action. In this context, our attention is focused on novel compounds acting on nuclear receptors, whose activity could be beneficial in viral infections, including coronavirus, hepatitis C virus, and cytomegalovirus.

Abstract

The manipulation of host metabolisms by viral infections has been demonstrated by several studies, with a marked influence on the synthesis and utilization of glucose, nucleotides, fatty acids, and amino acids. The ability of virus to perturb the metabolic status of the infected organism is directly linked to the outcome of the viral infection. A great deal of research in recent years has been focusing on these metabolic aspects, pointing at modifications induced by virus, and suggesting novel strategies to counteract the perturbed host metabolism. In this review, our attention is turned on PPARs, nuclear receptors controlling multiple metabolic actions, and on the effects played by PPAR ligands during viral infections. The role of PPAR agonists and antagonists during SARS-CoV-2, HCV, and HCMV infections will be analyzed.

Non-Alcoholic Fatty Liver Disease in HIV/HBV Patients - a Metabolic Imbalance Aggravated by Antiretroviral Therapy and Perpetuated by the Hepatokine/Adipokine Axis Breakdown

Non-alcoholic fatty liver disease (NAFLD) is strongly associated with the metabolic syndrome and is one of the most prevalent comorbidities in HIV and HBV infected patients. HIV plays an early and direct role in the development of metabolic syndrome by disrupting the mechanism of adipogenesis and synthesis of adipokines. Adipokines, molecules that regulate the lipid metabolism, also contribute to the progression of NAFLD either directly or via hepatic organokines (hepatokines). Most hepatokines play a direct role in lipid homeostasis and liver inflammation but their role in the evolution of NAFLD is not well defined. The role of HBV in the pathogenesis of NAFLD is controversial. HBV has been previously associated with a decreased level of triglycerides and with a protective role against the development of steatosis and metabolic syndrome. At the same time HBV displays a high fibrogenetic and oncogenetic potential. In the HIV/HBV co-infection, the metabolic changes are initiated by mitochondrial dysfunction as well as by the fatty overload of the liver, two interconnected mechanisms. The evolution of NAFLD is further perpetuated by the inflammatory response to these viral agents and by the variable toxicity of the antiretroviral therapy. The current article discusses the pathogenic changes and the contribution of the hepatokine/adipokine axis in the development of NAFLD as well as the implications of HIV and HBV infection in the breakdown of the hepatokine/adipokine axis and NAFLD progression.

Construction, Identification and Analysis of the Interaction Network of African Swine Fever Virus MGF360-9L with Host Proteins

African swine fever virus (ASFV) is prevalent in many countries and is a contagious and lethal virus that infects pigs, posing a threat to the global pig industry and public health. The interaction between the virus and the host is key to unlocking the mystery behind viral pathogenesis. A comprehensive understanding of the viral and host protein interaction may provide clues for developing new antiviral strategies. Here, we show a network of ASFV MGF360-9L protein interactions in porcine kidney (PK-15) cells. Overall, 268 proteins that interact with MGF360-9L are identified using immunoprecipitation and liquid chromatography–mass spectrometry (LC-MS). Accordingly, gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were conducted, and the protein–protein interaction (PPI) network was created. It was speculated that the cellular proteins interacting with MGF360-9L are involved in protein binding, metabolism, and the innate immune response. Proteasome subunit alpha type (PSMA3), 26S protease regulatory subunit 4 (PSMC1), autophagy and beclin 1 regulator 1 (AMBRA1), and DEAD-box helicase 20 (DDX20) could interact with MGF360-9L in vitro. PSMA3 and PSMC1 overexpression significantly promoted ASFV replication, and MGF360-9L maintained the transcriptional level of PSMA3 and PSMC1. Here, we show the interaction between ASFV MGF360-9L and cellular proteins and elucidate the virus–host interaction network, which effectively provides useful protein-related information that can enable further study of the potential mechanism and pathogenesis of ASFV infection.