Mendelian-randomization study revealed causal relationship between nonalcoholic fatty liver disease and osteoporosis/fractures.

BACKGROUND: Patients with nonalcoholic fatty liver disease (NAFLD) are reported to have a higher risk of osteoporosis/fractures; however, the causal relationship remains unclear. METHODS: Publicly available genome-wide association studies (GWASs) were used for Mendelian randomization (MR) analysis. GWASs of NAFLD and fractures were obtained from the FinnGen Consortium. GWASs of bone mineral density (BMD) were derived from a meta-analysis. GWASs of obesity, diabetes, liver function, and serum lipid-related metrics were used to clarify whether the accompanying NAFLD symptoms contributed to fractures. Moreover, two additional GWASs of NAFLD were applied. RESULTS: A causal association was not observed between NAFLD and BMD using GWASs from the FinnGen Consortium. However, a causal relationship between NAFLD and femoral neck-BMD (FN-BMD), a suggestive relationship between fibrosis and FN-BMD, and between NAFLD and osteoporosis were identified in replication GWASs. Genetically proxied body mass index (BMI), high-density lipoprotein (HDL), and hip circumference increased the likelihood of lower limb fractures. The waist-to-hip ratio decreased, whereas glycated hemoglobin (HbA1C) and homeostasis model assessment of ß-cell function (HOMA-B) increased the risk of forearm fractures. Low-density lipoprotein (LDL) reduced, whereas HbA1C increased the incidence of femoral fractures. Alkaline phosphatase (ALP) raised the risk of foot fractures. However, after a multivariate MR analysis (adjusted for BMI), all the relationships became insignificant. CONCLUSIONS: NAFLD caused reduced BMD, and genetically predicted HDL, LDL, HbA1C, HOMA-B, ALP, hip circumference, and waist-to-hip ratio causally increased the risk of fractures. BMI may mediate causal relationships. Larger GWASs are required to verify this finding.

Improved bone and renal safety in younger tenofovir disoproxil fumarate experienced chronic hepatitis B patients after switching to tenofovir alafenamide or entecavir.

INTRODUCTION AND OBJECTIVES: Renal and bone impairment has been reported in chronic hepatitis B (CHB) patients receiving long-term tenofovir disoproxil fumarate (TDF) therapy. This study aimed to assess the incidence of renal and bone impairment in CHB patients with long-term TDF therapy and to identify the changes in bone mineral density (BMD) and renal function in these patients after switching to entecavir (ETV) or tenofovir alafenamide (TAF). MATERIALS AND METHODS: This retrospective study collected clinical data from CHB patients who received TDF monotherapy over 96 weeks. The changes in BMD and renal function were analyzed after 96 weeks of switching antiviral regimens (ETV or TAF) or maintenance TDF. RESULTS: At baseline, 154 patients receiving TDF monotherapy over 96 weeks were enrolled, with a younger median age of 36.75 years, 35.1% (54/154) of patients experienced elevated urinary ß2 microglobulin and 20.1% (31/154) of patients had reduced hip BMD (T<-1). At week 96, among the 123 patients with baseline normal BMD, patients who maintained TDF (n=85) had experienced a decrease in hip BMD, while patients who switched antiviral regimens (n=38) experienced an increase (-13.97% vs 2.34%, p<0.05). Among patients with a baseline reduced BMD (n=31), the alterations in BMD were similar in patients who maintained TDF (n=5) and those who switched antiviral regimens (n=26) (-15.81% vs 7.35%, p<0.05). Irrespective of baseline BMD status, renal function decreased significantly in patients who maintained TDF and improved in patients who switched antiviral regimens. CONCLUSIONS: Younger CHB patients on long-term TDF therapy are at high risk for bone and renal impairment, with the risk being reduced when switched to ETV or TAF.

Hepatitis B Core-Related Antigen to Indicate High Viral Load: Systematic Review and Meta-Analysis of 10,397 Individual Participants.

BACKGROUND & AIMS: To eliminate hepatitis B virus (HBV) infection, scale-up of testing and treatment in resource-limited countries is crucial. However, access to nucleic acid testing to quantify HBV DNA, an essential test to examine treatment eligibility, remains severely limited. We assessed the performance of a novel immunoassay, HBV core-related antigen (HBcrAg), as a low-cost (less than US $15/assay) alternative to nucleic acid testing to indicate clinically important high viremia in chronic HBV patients infected with different genotypes. METHODS: We searched Medline, Embase, Scopus, and Web of Science databases through June 27, 2018. Three reviewers independently selected studies measuring HBV DNA and HBcrAg in the same blood samples. We contacted authors to provide individual participant data (IPD). We randomly allocated each IPD to a derivation or validation cohort. We applied optimal HBcrAg cut-off values derived from the derivation set to the validation set to estimate sensitivity/specificity. RESULTS: Of 74 eligible studies, IPD were obtained successfully for 60 studies (81%). Meta-analysis included 5591 IPD without antiviral therapy and 4806 treated with antivirals. In untreated patients, the pooled area under the receiver operating characteristic curve and optimal cut-off values were as follows: 0.88 (95% CI, 0.83-0.94) and 3.6 log U/mL to diagnose HBV DNA level of 2000 IU/mL or greater; and 0.96 (95% CI, 0.94-0.98) and 5.3 log U/mL for 200,000 IU/mL or greater, respectively. In the validation set, the sensitivity and specificity were 85.2% and 84.7% to diagnose HBV DNA level of 2000 IU/mL or greater, and 91.8% and 90.5% for 200,000 IU/mL or greater, respectively. The performance did not vary by HBV genotypes. In patients treated with anti-HBV therapy the correlation between HBcrAg and HBV DNA was poor. CONCLUSIONS: HBcrAg might be a useful serologic marker to indicate clinically important high viremia in treatment-naïve, HBV-infected patients.

Distribution and factors associated with serum HBV pregenomic RNA levels in Chinese chronic hepatitis B patients.

Correlations between serum hepatitus B virus (HBV) pregenomic RNA (pgRNA), hepatitus B surface antigen (HBsAg), and hepatitus B core-related antigen (HBcrAg) levels, and influencing factors of serum HBV pgRNA levels in Chinese chronic hepatitis B (CHB) patients are rarely reported. This was a retrospective cohort study consisting of 204 outpatients with CHB. Serum levels of HBV pgRNA, HBsAg, and HBcrAg were quantitative measured in frozen blood samples. The linear regression and multivariate logistic regression analysis were performed to determine associated factors of serum HBV pgRNA levels. In this cohort, the median serum HBV pgRNA level was 4.12 log10 copies/ml and 33.33% (68/204) of them had serum HBV pgRNA under low limit of detection (LLD) (<500 copies/ml); and the percentage of patients with serum HBV pgRNA under LLD in hepatitis B e antigen (HBeAg)-positive patients was significantly lower than that in HBeAg-negative patients (15.75% [23/46] vs. 77.59% [45/58], p < .001). Overall, serum HBV pgRNA strongly correlated with HBcrAg (r = 0.760, p < .001), and moderately correlated with HBV DNA (r = 0.663, p < .001) and HBsAg (r = 0.670, p < .001). As compared with HBsAg and HBV DNA, only HBcrAg showed stable correlation with serum HBV pgRNA both in HBeAg-positive and HBeAg-negative patients. Serum HBV pgRNA level differed between HBeAg-positive and HBeAg-negative patients; and it had better and more stable correlation with serum HBcrAg than serum HBV DNA and HBsAg, irrespective of HBeAg status.

Optimal drug administration manner would rescue partial virological response in chronic hepatitis B patients with entecavir or tenofovir treatment.

Not all treatment-naïve patients receiving entecavir (ETV) or tenofovir disoproxil fumarate (TDF) therapy can achieve complete virological response, and many factors may be related with the outcome of partial virological response. This study aimed to determine whether the manner of drug administration affects the antiviral efficacy of ETV/TDF monotherapy. All eligible patients were divided into complete or partial response cohorts based on their virological response following 24-week therapy. Factors related with partial response were evaluated. Patients with partial response were further grouped depending on whether they later adjusted the manner of drug administration, and the antiviral efficacy was compared between the two groups during prolonged treatment. A total of 518 patients were enrolled. Suboptimal drug administration (OR 77.511, P = .000), positive-HBeAg (OR 3.191, P = .000) and ETV treatment (OR 2.537, P = .001) were identified as independent risk factors for partial response. Among patients with partial response, 213 were in the adjusted group and 76 were in the unadjusted group. The percentages of patients with undetectable serum HBV DNA (78.9% vs 31.6%, P < .001) and with normal alanine aminotransferase (ALT) (88.7% vs 68.4%, P < .001) were both higher in the adjusted group than that in unadjusted group following a further 6-month therapy. In conclusion, the manner of drug administration is an important factor influencing the efficacy of ETV/TDF therapy, and optimal drug administration manner can help to increase antiviral efficacy and rescue patients with partial response.

Tenofovir monotherapy versus tenofovir plus entecavir combination therapy in HBeAg-positive chronic hepatitis patients with partial virological response to entecavir.

AIMS: The aim of this retrospective study was to compare the efficacy and safety of tenofovir disoproxil fumarate (TDF) monotherapy and TDF + entecavir (ETV) combination therapy for chronic hepatitis B (CHB) patients with the partial virological response (PVR) to ETV. METHODS: CHB patients with PVR to ETV were switched to TDF monotherapy or TDF + ETV combination therapy. The primary efficacy outcome was a virological response (VR), and the secondary efficacy outcomes were hepatitis B e antigen (HBeAg) seroconversion and alanine aminotransferase (ALT) normalization. The primary safety outcomes were changes in serum creatinine and serum phosphorus levels. RESULTS: A total of 143 patients were investigated, including 63 patients in the TDF monotherapy group and 80 patients in the TDF + ETV combination therapy group. Baseline demographics and clinical characteristics were comparable between groups. The median age of patients was 44.5 years, and 76.2% of them were male. The VR rate in TDF + ETV group was higher than that of the TDF group at 48 weeks (88.8% vs 71.4%; P = .009). At 48 weeks, the HBeAg seroconversion rate of TDF + ETV group was higher than that of the TDF group (30% vs 15.9%; P = .049). There was no significant difference in the proportion of patients with elevated ALT in the TDF group and TDF + ETV group at 48 weeks (9.5% vs 7.5%; P = .665). After adjusting the treatment regimen, serum creatinine levels increased slightly and serum phosphorus level decreased slightly in both groups. CONCLUSIONS: TDF + ETV combination therapy for 48 weeks had a higher VR rate than TDF monotherapy in CHB patients with PVR to ETV.

Present and Future Therapies for Chronic Hepatitis B.

Chronic hepatitis B (CHB) remains the leading cause of liver-related morbidity and mortality across the world. If left untreated, approximately one-third of these patients will progress to severe end-stage liver diseases including liver failure, cirrhosis, and hepatocellular carcinoma (HCC). High level of serum HBV DNA is strongly associated with the development of liver failure, cirrhosis, and HCC. Therefore, antiviral therapy is crucial for the clinical management of CHB. Current antiviral drugs including nucleoside/nucleotide analogues (NAs) and interferon-α (IFN-α) can suppress HBV replication and reduce the progression of liver disease, thus improving the long-term outcomes of CHB patients. This chapter will discuss the standard and optimization antiviral therapies in treatment-naïve and treatment-experienced patients, as well as in the special populations. The up-to-date advances in the development of new anti-HBV agents will be also discussed. With the combination of the current antiviral drugs and the newly developed antiviral agents targeting the different steps of the viral life cycle or the newly developed agents modulating the host immune responses, the ultimate eradication of HBV will be achieved in the future.

Apolipoprotein A5 alleviates LPS/D-GalN-induced fulminant liver failure in mice by inhibiting TLR4-mediated NF-κB pathway.

BACKGROUND: Fulminant liver failure (FHF) is a serious clinical problem and liver transplantation is the major intervention. But the overall survival rate of FHF is low owing to the donated organ shortage. Apolipoprotein A-V (ApoA5) is a regulator of triglyceride metabolism and has been reported to act as a predictor for remnant liver growth after preoperative portal vein embolization and liver surgery. This study aimed to investigate the therapeutic effect of ApoA5 on lipopolysaccharide/D-galactosamine (LPS/D-GalN)-induced fulminant liver failure in mice. METHODS: FHF mouse model was established using LPS/D-GalN and ApoA5 plasmid was injected by tail vein prior to LPS/D-GalN treatment. The expressions of ApoA5, toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88), and nuclear factor kappa B p65 (NF-κBp65) were assessed by real-time PCR and western blotting. Serum alanine aminotransferase (ALT) and tumor necrosis factor-α (TNF-α) levels were measured using automatic biochemical analyzer. Histological assessment and immunohistochemical (IHC) staining were conducted. Survival rate after LPS/D-GalN administration was also determined with Kaplan-Meier curve. Meanwhile, the expression of ApoA5 in injured huh7 cells was tested. Cell apoptosis analysis was performed after huh7 cells were transfected with ApoA5 plasmid and stimulated with LPS. RESULTS: The expressions of ApoA5 decreased both in injured huh7 cells and FHF mice. ApoA5 overexpression reduced cell death rate using flow cytometry. ApoA5 not only decreased the serum ALT and TNF-α levels but also attenuated hepatic damage in hematoxylin-eosin (HE)-stained liver section. The protein expressions of TLR4, MyD88 and NF-κBp65 were inhibited when ApoA5 overexpressed. But the inhibitory effect would weaken with the increasing concentration of LPS in spite of ApoA5 overexpression. Besides, ApoA5 improved liver injury in a dose-dependent manner and the survival rate in FHF mice increased with increasing concentration of ApoA5. CONCLUSION: ApoA5 had a protective effect against LPS/D-GalN-induced fulminant liver failure in mice within a certain range by inhibiting TLR4-mediated NF-κB pathway.

Safety and efficacy of sofosbuvir-based direct-acting antiviral regimens for hepatitis C virus genotype 6 in Southwest China: Real-world experience of a retrospective study.

Optional treatments for patients with chronic hepatitis C virus (HCV) genotype (GT) 6 infection have not been extensively studied. This study aimed to evaluate the safety and efficacy of sofosbuvir (SOF)-based direct-acting antiviral agents (DAAs) for HCV GT6. We performed a retrospective study at the West China Hospital of Sichuan University in Southwest China from January 2016 to May 2017. Our study screened 130 treatment-naïve patients with chronic HCV GT6 and without liver cirrhosis. A total of 60 HCV GT6 patients were ultimately enrolled. All patients received SOF-based DAAs therapy, including SOF 400 mg plus daclatasvir (DCV) 60 mg daily or SOF 400 mg plus velpatasvir (VEL) 100 mg daily for 12 weeks. The sustained virological response 12 weeks after treatment (SVR12) was 100% (60/60) in treatment-naïve patients with HCV GT6, including 100% (37/37) of patients receiving SOF plus DCV therapy and 100% (23/23) of patients receiving SOF plus VEL therapy. Measurements of liver stiffness were significantly decreased in patients at week 12 (P = 0.014) and week 24 (P < 0.001) of DAAs treatment compared to baseline values. The serum biomarker aspartate aminotransferase-to-platelet ratio index (APRI) and fibrosis-4 score were also significantly reduced at week 12 and week 24 compared to before treatment (both P < 0.001). SOF-based therapy was well-tolerated, and no serious adverse events were reported. In conclusion, SOF plus DCV and SOF plus VEL were safe and achieved a high SVR12 rate for treatment-naïve patients with HCV GT6 without liver cirrhosis.

Serum HBcrAg is better than HBV RNA and HBsAg in reflecting intrahepatic covalently closed circular DNA.

The correlation between serum HBcrAg and HBV RNA is unclear, and correlations of intrahepatic cccDNA with HBcrAg, HBV RNA and HBsAg are rarely reported in the same cohort. This study aimed to assess the correlation of HBcrAg with HBV RNA and HBsAg, and investigate whether serum HBcrAg is superior to serum HBV RNA and HBsAg in reflecting intrahepatic HBV cccDNA in HBeAg-positive and HBeAg-negative CHB patients. In this study, 85 HBeAg-positive and 25 HBeAg-negative patients who have never received antiviral therapy were included. Among HBeAg-positive patients, HBcrAg was correlated positively with HBsAg (r = 0.564, P < 0.001) and HBV RNA (r = 0.445, P < 0.001), and HBV RNA was also correlated positively with HBsAg (r = 0.323, P = 0.003). Among HBeAg-negative patients, no significant correlation was observed between HBcrAg, HBsAg and HBV RNA. By multivariable linear regression, HBcrAg (ß = -0.563, P < 0.001), HBsAg (ß = -0.328, P < 0.001) and HBV RNA (ß = 0.180, P = 0.003) were all associated with cccDNA levels among HBeAg-positive patients, but only serum HBcrAg was associated with cccDNA level (ß = 0.774, P = 0.000) among HBeAg-negative patients. HBcrAg was better correlated with cccDNA as compared to HBsAg and HBV RNA, irrespective of HBeAg status. Among HBeAg-positive patients, though HBcrAg level was influenced by hepatic inflammatory activity and HBV DNA levels, the good correlations of HBcrAg with cccDNA persisted after stratification by inflammatory activity and HBV DNA levels. In conclusion, correlations of serum HBcrAg, HBV RNA and HBsAg levels differ significantly between HBeAg-positive and HBeAg-negative patients, but serum HbcrAg correlates with cccDNA levels better than HBV RNA and HBsAg, irrespective of HBeAg status.

The truncated mutant HBsAg expression increases the tumorigenesis of hepatitis B virus by regulating TGF-ß/Smad signaling pathway.

BACKGROUND: It has been reported that the emergence of HBV rtA181T/sW172* mutant could result in a dominant secretion defect of HBsAg and increase the risk of HCC development. This study was designed to reveal the role and possible pathogenic mechanism of truncated mutant HBsAg in tumorigenesis of HBV rtA181T/sW172* mutant. RESULTS: As compared to wide type or substituted mutant HBsAg, the ratio of cell clones was significant higher in L02 cells stable expressing truncated mutant HBsAg. Injection of L02 cells stable expressing truncated mutant HBsAg into the dorsal skin fold of nude mice resulted in increased primary tumor growth compared to L02 cells stable expressing wide-type and substituted mutant HBsAg. In HBV replication L02 cell lines, the key molecular involved in TGF-ß/Smad pathway was also investigated. We found that the mRNA and protein levels of Smad3/2, CREB and CyclinD1 were significantly higher and TGFBI level was significantly lower in cells stably expressing truncated mutant HBsAg as compared to cells stably expressing wide-type and substituted mutant HBsAg. Additionally, after administration of TGF-ß1 (increasing TGFBI level), the volume of tumor is obviously reduced in nude mice with injection of L02 cells stable expressing truncated HBsAg. CONCLUSIONS: The emergence of sW172* mutant may increase the tumorigenesis of HBV, and its mechanism may be associated with down-regulated expression of TGFBI in TGF-ß/Smad signaling pathway.

Satisfactory virological response and fibrosis improvement of sofosbuvir-based regimens for Chinese patients with hepatitis C virus genotype 3 infection: results of a real-world cohort study.

BACKGROUND: Chronic hepatitis C virus (HCV) genotype (GT) 3 infection with advanced liver disease has emerged as a challenging to treat by direct-acting antivirals (DAAs), but the efficacy of DAAs in Chinese HCV-GT3 patients is rarely reported. This study aimed to analyze the efficacy of sofosbuvir (SOF)-based regimens in Chinese patients with HCV-GT3 and compensated liver disease. METHODS: This was a registered retrospective study. All patients had completed at least 12 weeks SOF-based regimens therapy (with or without RBV), and were followed up for at least 24 weeks after therapy discontinuation. The primary endpoint was sustained virological response 24 weeks after end of therapy (SVR24). RESULTS: A total of 102 patients who completed at least 12 weeks therapy were finally included, with 57 in SOF + Daclatasvir (SOF + DCV), 24 in SOF + DCV + ribavirin (RBV) and 21 in SOF/Velpatasvir (SOF/VEL). The total SVR24 rate was achieved in 90.20% (92/102), with 85.96% (49/57) in SOF + DCV, 91.67% (22/24) in SOF + DCV + RBV and 100.00% (21/21) in SOF/VEL. Among 10 relapsed patients (8 in SOF + DCV and 2 in SOF + DCV + RBV), the short course (12 weeks) of therapy and no RBV addition may be the leading cause. In this cohort, the SVR24 rate was not statistically different between patients with and without cirrhosis (81.82% [27/33] vs. 94.20% [65/69], P = 0.073). Additionally, both FIB-4 (4.03 vs. 2.08, P < 0.001) and APRI (2.15 vs. 0.68, P < 0.001) scores were significant improved from baseline to week 24 after completion of therapy, regardless of the presence of cirrhosis. CONCLUSION: SOF-based regimens are highly effective in viral clearance and fibrosis remission for Chinese patients with HCV-GT3 infection. If available, SOF/VEL should be first considered.

M2BPGi as a potential diagnostic tool of cirrhosis in Chinese patients with Hepatitis B virus infection.

BACKGROUND: M2BPGi is a novel serum glycobiomarker of liver fibrosis. In this study, we aimed to evaluate the efficacy of M2BPGi for predicting liver fibrosis and disease progression in Chinese hepatitis B virus (HBV) infected patients. METHODS: We enrolled 228 HBV infected patients with different status of liver fibrosis diagnosed using FibroScan. We analyzed the diagnostic accuracy of M2BPGi, and compared it with AST-to-platelet ratio (APRI), FIB-4 index, AST to ALT ratio (AAR), and RDW to platelet ratio (RPR). We performed receiver operating characteristics curve (ROC) to evaluate the diagnostic performance of M2BPGi for significant fibrosis and cirrhosis. RESULTS: Median M2BPGi values in each fibrosis stage were: 0.88 cut-off index (COI) in F0-1, 1.165 in F2-3, and 1.92 in F4 (P<.01), respectively. For F≥2, the sensitivity, specificity, accuracy of M2BPGi were 72.28%, 73.23%, 66.67%, while 55.07%, 93.71%, 82.02% for F≥4. For predicting significant fibrosis (≥F2), M2BPGi showed comparable performance to FIB4 index (P<.01), APRI (P<.01) and RPR (P<.01) with area under the ROC curve (AUC) of 0.788. M2BPGi was superior to other surrogate markers for diagnosing cirrhosis (F4) with the highest AUC of 0.811 (P<.01). CONCLUSIONS: M2BPGi levels increased with the progression of liver fibrosis in HBV infected patients. M2BPGi can be served as a potential glycobiomarker to assess the stage of liver fibrosis, especially for the diagnosis of cirrhosis.

Pronounced decline of serum HBsAg in chronic hepatitis B patients with long-term effective nucleos(t)ide analogs therapy.

AIMS: This study aims to investigate the kinetics of serum HBsAg levels in chronic hepatitis B patients with long-term nucleos(t)ide analogs (NAs) therapy. METHODS: This was a retrospective clinical study. Serum HBsAg in serial samples of 94 patients, who received at least 8 years of NAs therapy, were measured using Elecsys® HBsAg II Quant Assay. RESULTS: In this cohort, serum HBsAg levels reduced from 3.80 log10 IU/mL at baseline to 2.72 log10 IU/mL at year 8 (p < .001), and the percentage of patients with HBsAg <1000 IU/mL increased from 14.9% at baseline to 55.3% at year 8 (p < .001). The reduction of serum HBsAg did not differ significantly between patients stratified by baseline virological parameters and type of antiviral agents. But as compared to patients without HBeAg seroconversion, HBsAg levels were significant lower in patients with HBeAg seroconversion (3.19 vs. 2.47 log10 IU/mL at year 8, p = .001). As compared to patients with slow (0-1 log10 IU/mL) or steady HBsAg(≤0 log10 IU/mL) decline at year 1, patients with a rapid HBsAg (≥1 log10 IU/mL) decline had a significantly lower HBsAg levels from year 2 to 8. However, Cox regression analysis showed that only absolute HBsAg levels at year 1 was an independent predictor of subsequent HBsAg <1000 IU/mL at year 8 of antiviral therapy(HR 0.242, p = .004). CONCLUSION: Pronounced HBsAg declines could be achieved in patients after long-term effective therapy with NAs, and on-treatment low serum HBsAg level at year 1 might be a predictor of serum HBsAg <1000 IU/mL at year 8.

Liver Regeneration: Analysis of the Main Relevant Signaling Molecules.

Liver regeneration is a highly organized tissue regrowth process and is the most important reaction of the liver to injury. The overall process of liver regeneration includes three phases: priming stage, proliferative phase, and termination phase. The initial step aims to induce hepatocytes to be sensitive to growth factors with the aid of some cytokines, including TNF-α and IL-6. The proliferation phase promotes hepatocytes to re-enter G1 with the stimulation of growth factors. While during the termination stage, hepatocytes will discontinue to proliferate to maintain normal liver mass and function. Except for cytokine- and growth factor-mediated pathways involved in regulating liver regeneration, new substances and technologies emerge to influence the regenerative process. Here, we reviewed novel and important signaling molecules involved in the process of liver regeneration to provide a cue for further research.

Employment of digital gene expression profiling to identify potential pathogenic and therapeutic targets of fulminant hepatic failure.

BACKGROUND: The dysregulated cytokine metabolism and activity are crucial to the development of fulminant hepatic failure (FHF), and many different cytokines have been identified. However, the precise gene expression profile and their interactions association with FHF are yet to be further elucidated. METHODS: In this study, we detected the digital gene expression profile (DGEP) by high-throughput sequencing in normal and FHF mouse liver, and the candidate genes and potential targets for FHF therapy were verified. And the FHF mouse model was induced by D-Galactosamine (GalN)/lipopolysaccharide (LPS). RESULTS: Totally 12727 genes were detected, and 3551 differentially expressed genes (DEGs) were obtained from RNA-seq data in FHF mouse liver. In FHF mouse liver, many of those DEGs were identified as differentially expressed in metabolic process, biosynthetic process, response to stimulus and response to stress, etc. Similarly, pathway enrichment analysis in FHF mouse liver showed that many significantly DEGs were also enriched in metabolic pathways, apoptosis, chemokine signaling pathways, etc. Considering the important role of nuclear factor-kappa B (NF-κB) in metabolic regulation and delicate balance between cell survival and death, several DEGs involved in NF-κB pathway were selected for experimental validation. As compared to normal control, NF-κBp65 and its inhibitory protein IκBα were both significantly increased, and NF-κB targeted genes including tumor necrosis factor α(TNFα), inducible nitric oxide synthase (iNOS), interleukin-1ß, chemokines CCL3 and CCL4 were also increased in hepatic tissues of FHF. In addition, after NF-κB was successfully pre-blocked, there were significant alteration of hepatic pathological damage and mortality of FHF mouse model. CONCLUSIONS: This study provides the globe gene expression profile of FHF mouse liver, and demonstrates the possibility of NF-κB gene as a potential therapeutic target for FHF.

The efficacy of zinc finger antiviral protein against hepatitis B virus transcription and replication in tansgenic mouse model.

AIM: The zinc finger antiviral protein (ZAP) is a mammalian host restriction factor, and it could inhibit HBV RNA synthesis in vitro experiments. However, the role of ZAP against HBV in vivo environment is unclear. This study aimed to investigate whether ZAP could act against HBV transcription and replication in ZAP tansgenic mouse model. METHODS: HBV-replication-competent plasmid pHBV4.1 was transferred to ZAP transgenic ICR mouse via the tail vein using a hydrodynamic in vivo transfection procedure, and ICR mouse were used as controls. HBV RNA and HBV DNA replication intermediates in the liver were respectively analyzed by Northern blotting and Southern blotting. The expression of hepatitis B surface antigen (HBsAg) and hepatitis B core antigen (HBcAg) in the liver tissue was detected by immunohistochemical staining. RESULTS: As compared to ICR control mouse, the levels of 3.5 kb mRNA in ZAP transgenic mouse were decreased by 8.4%; while the level of HBV DNA replication intermediates was decreased by 82%. In addition, the expression of HBsAg and HBcAg in ZAP transgenic mouse liver were both significantly less than that of ICR control mouse. CONCLUSIONS: Our findings suggest that ZAP could inhibit HBV replication in vivo in mice, which offers a new target for anti-HBV drug development.