scholarly journals The cooperative complex of Argonaute-2/MicroRNA-146a regulates Hepatitis B Virus replication through FEN1

2020 ◽  
Author(s):  
min ji ◽  
Xiaoping Mei ◽  
Xunming Jing ◽  
Xu Xu ◽  
Xing Chen ◽  
...  
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Hbv Dna ◽  
Expression Level ◽  
Control Group ◽  
Transcriptional Level ◽  
Downstream Target ◽  
Hbv Replication ◽  
Hbv Cccdna ◽  
B Virus

Abstract Background: The regulatory of HBV replication is still unclear. FEN1 can repair HBV rcDNA to HBV cccDNA and promote HBV DNA replication. However, its specific regulatory detail remains unclear. MicroRNA regulates gene expression at post-transcriptional level. Especially, miR-146a, it plays an important role that is closely related to regulation of HBV replication. Based on above, we hypothesize that miR-146a may be regulate HBV cccDNA formation through FEN1. So, we will investigate the effect of miR-146a on the replication of hepatitis B virus and its molecular mechanism. Results: We found that level of miR-146a was significantly up-regulated in HepG2.2.15 cells (11.755±0.069) than that in HepG2 (1.000±0.038) (P<0.05). Furthermore, HBV-DNA copies and FEN1 were significantly increased and decreased, respectively, in HepG2.2.15 cells transfected with miR-146a mimic and inhibitor for 48h,[(3.215±0.001); (2.623±0.083)] compared with the control group (2.813±0.015) (P<0.05),. After transfection FEN1 plasmid, HBV-DNA Copies (5.712±0.371) is significantly higher than the control group（2.661±0.009）(P<0.05), and the level of miR-146a（3.431±0.004）is significantly higher than the control group (1.023±0.224） (P<0.05). The expression level of IRAK1/TRAF6 are significantly lower and higher [(0.114±0.013); (0.390±0.014); (1.222±0.073); (2.145±0.271)] than the control group [(1.000±0.038); (1.007±0.119)] (P<0.05) after transfection miR-146a mimic and inhibitor into HepG2.2.15. After Ago2 siRNA, the level of miR-146a (0.105±0.002) is significantly decreased than the control group (1.000±0.041) (P<0.05) from Ago2 protein RIP. After transfection Ago2 siRNA then added into exogenous miR-146a into HepG2.2.15, The expression level of FEN1 is significantly reduced (0.485±0.100) than the control group (1.000±0.023) (P<0.05), and the HBV-DNA copies is significantly lower (3.230±0.047) than the control group (3.789±0.041) (P<0.05). Conclusion: Ago2 cooperates with miR-146a to regulate the transcription the expression level of FEN1 protein through the downstream target gene IRAK1/TRAF6, then promoting HBV replication.

scholarly journals MicroRNA-802 induces hepatitis B virus replication and replication through regulating SMARCE1 expression in hepatocellular carcinoma

2019 ◽  
Vol 10 (10) ◽  
Author(s):  
Yuanyuan Wang ◽  
Jingmei Cao ◽  
Shiyun Zhang ◽  
Lei Sun ◽  
Yi Nan ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Hepatitis B Virus ◽  
Dna Replication ◽  
Hepatitis B ◽  
Functional Role ◽  
Ectopic Expression ◽  
Hbv Dna ◽  
Expression Level ◽  
Hbv Replication ◽  
B Virus

Abstract Growing evidences have indicated that microRNAs (miRNAs) can regulate hepatitis B virus (HBV) expression and replication, playing crucial roles in the development of HBV infection. Until now, the functional role and mechanism of miR-802 in HBV replication and expression remain unknown. We indicated that miR-802 expression was upregulated in the HBV-associated hepatocellular carcinoma (HCC) tissues compared with the adjacent noncancerous samples. In addition, we showed that the SMARCE1 expression level was downregulated in the HBV-associated HCC tissues compared with the adjacent noncancerous samples. miR-802 expression was negatively related with MARCE1 expression in HBV-associated HCC tissues. Moreover, miR-802 expression was upregulated, and SMARCE1 expression was downregulated in the HBV-infected HepG2.2.15 cells. Ectopic expression of miR-802 significantly enhanced HBV DNA replication, while knockdown of miR-802 significantly decreased HBV DNA replication. We showed that overexpression of miR-802 promoted HbsAg and HbeAg expression, while inhibition of miR-802 decreased HbsAg and HbeAg expression. Furthermore, we indicated that ectopic expression of SMARCE1 suppressed HBV DNA replication and decreased the expression level of HbsAg and HbeAg. Finally, we showed that overexpression of miR-802 promoted HBV DNA replication through regulating SMARCE1 expression. These results suggested the important roles of miR-802 on HBV expression and replication, which may shed new light on the development of treatment for HBV.

scholarly journals Phosphorothioate Di- and Trinucleotides as a Novel Class of Anti-Hepatitis B Virus Agents

2004 ◽  
Vol 48 (6) ◽  
pp. 2199-2205 ◽  
Author(s):  
Radhakrishnan P. Iyer ◽  
Yi Jin ◽  
Arlene Roland ◽  
John D. Morrey ◽  
Samir Mounir ◽  
...  
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Nucleoside Analogs ◽  
Hbv Dna ◽  
Parallel Synthesis ◽  
Hbv Replication ◽  
Long Term Treatment ◽  
B Virus ◽  
Dna Strand

ABSTRACT Several nucleoside analogs are under clinical development for use against hepatitis B virus (HBV). Lamivudine (3TC), a nucleoside analog, and adefovir dipivoxil (ADV), an acyclonucleotide analog, are clinically approved. However, long-term treatment can induce viral resistance, and following the cessation of therapy, viral rebound is frequently observed. There continues to be a need for new antiviral agents with novel mechanisms of action. A library of more than 600 di- and trinucleotide compounds synthesized by parallel synthesis using a combinatorial strategy was screened for potential inhibitors of HBV replication using the chronically HBV-producing cell line 2.2.15. Through an iterative process of synthesis, lead optimization, and screening, three analogs were identified as potent inhibitors of HBV replication: dinucleotides ORI-7246 (drug concentration at which a 10-fold reduction of HBV DNA was observed [EC90], 1.4 μM) and ORI-9020 (EC90, 1.2 μM) and trinucleotide ORI-7170 (EC90, 7.2 μM). These analogs inhibited the replication of both strands of HBV DNA. No suppression of HBV protein synthesis or intracellular core particle formation by these analogs was observed. No inhibition of HBV DNA strand elongation by the analogs or their 5′-triphosphate versions was apparent in in vitro polymerase assays. Although the exact mechanism of action is not yet identified, present data are consistent with an inhibition of the HBV reverse transcriptase-directed priming step prior to elongation of the first viral DNA strand. In transient-transfection assays, these analogs inhibited the replication of 3TC-resistant HBV. Synergistic interactions in combination treatments between the analogs and either 3TC or ADV were observed. These compounds represent a novel class of anti-HBV molecules and warrant further investigation as potential therapeutic agents.

The possible role of S gene mutations of hepatitis B virus in intrauterine transmission

2020 ◽  
Author(s):  
Jiaxin Wu ◽  
Yongliang Feng ◽  
Zhiqing Yang ◽  
Ruijun Zhang ◽  
Dandan Wang ◽  
...  
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Hepatitis B Surface Antigen ◽  
Gene Mutations ◽  
Hbv Dna ◽  
Mutation Rates ◽  
Control Group ◽  
Intrauterine Transmission ◽  
S Gene ◽  
B Virus

Abstract Background: Many hepatitis B virus (HBV) substances could inevitably enter fetuses and occurred neonatal intrauterine transmission. HBV often occurs mutation, especially S gene, and may lead to different outcomes on intrauterine transmission. We explored the associations between HBV S gene mutations of hepatitis B surface antigen positive (HBsAg-positive) mothers and intrauterine transmission. Methods: A total of 399 HBsAg-positive mothers and neonates were recruited and their general demographic information was collected between June 2011 and July 2013. The mothers with HBV DNA levels ≥ 106 IU/ml were selected, 22 mothers whose neonates occurred HBV intrauterine transmission were in the HBV intrauterine transmission group (GT) and 22 mothers were randomly selected from the remaining controls were in the control group (GC). Maternal whole-genome HBV DNA was extracted, amplified, cloned, and sequenced. Obtained sequences were adjusted, genotyped, and analyzed for mutation rates. A case-control study was designed to analyze the relationship between mutations in the S gene of HBV and intrauterine transmission. Results: Fifty-five neonates were found to have experienced intrauterine transmission (13.78%). Genotype B (4.55%), genotype C (88.64%) and inter-genotype B/C (6.81%) were found in the 44 HBsAg-positive mothers. The mutation rates of the S gene, in both genotypes B (0.58% vs 1.41%, P = 0.040) and C (7.56% vs 14.71%, P＜0.001), were lower in group T than in group C. Missense substitutions such as L84I, P47S, K10Q, A41P, M133L, A60V, and I42T only existed in group C. The mutation rates of G73S, I126T, and I126S in group C were higher (P < 0.001, P < 0.001, P = 0.010). Deletions occurred in the S gene. The occurrence of intrauterine transmission with maternal mutation A90V was higher (P < 0.001). This may have increased the risk of neonatal HBsAg expression (P = 0.022). Conclusions: The HBV S gene mutations of HBsAg-positive mothers may reduce the occurrence of HBV intrauterine transmission. It is possible for HBsAg-positive mothers infected with A90V to develop HBV chronic infection and transmit it to the fetus during pregnancy, resulting in neonatal HBV infection.

scholarly journals The efficacy and safety of methylprednisolone in hepatitis B virus-related acute-on-chronic liver failure: a prospective multi-center clinical trial

BMC Medicine ◽  
2020 ◽  
Vol 18 (1) ◽  
Author(s):  
Lin Jia ◽  
Ran Xue ◽  
Yueke Zhu ◽  
Juan Zhao ◽  
Juan Li ◽  
...  
Keyword(s):  
Hepatitis B Virus ◽  
Dna Replication ◽  
Hepatitis B ◽  
Liver Failure ◽  
Standard Treatment ◽  
Hbv Dna ◽  
Control Group ◽  
Efficacy And Safety ◽  
Chronic Liver Failure ◽  
B Virus

Abstract Background Hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) is a severe condition with high mortality due to lack of efficient therapy. Until now, the use of methylprednisolone (MP) in HBV-ACLF is still controversial. We aimed to evaluate the efficacy and safety of MP in HBV-ACLF. Methods Totally 171 HBV-ACLF patients from three medical centers were randomly allocated into MP group (83 patients treated with MP intravenously guttae for 7 days plus standard treatment: 1.5 mg/kg/day [day 1–3], 1 mg/kg/day [day 4–5], and 0.5 mg/kg/day [day 6–7]) and control group (88 patients treated with standard treatment). The primary endpoints were 6-month mortality and prognostic factors for 6-month survival. The survival time, cause of death, adverse events, liver function, and HBV DNA replication were analyzed. Results The 6-month mortality was significantly lower in MP group than control group [32.4% vs. 42.5%, P = 0.0037]. MP treatment was an independent prognostic factor for 6-month survival [HR (95% CI) 0.547(0.308–0.973); P = 0.040]. Factors associated with reduced 6-month mortality in MP group included HBV DNA and lymphocyte/monocyte ratio (LMR) (P < 0.05). Based on ROC curve, LMR+MELD had a better predictive value for prognosis of HBV-ACLF under MP treatment. No significant difference in HBV DNA replication was observed between groups (P > 0.05). Conclusions MP therapy is an effective and safe clinical strategy in HBV-ACLF, increasing the 6-month survival rate. Clinical trials registered at http://www.chictr.org.cn as ChiCTR-TRC-13003113 registered on 16 March 2013.

scholarly journals Diagnostic Value of Detection of Pregenomic RNA in Sera of Hepatitis B Virus-Infected Patients with Different Clinical Outcomes

2019 ◽  
Vol 58 (2) ◽  
Author(s):  
Ni Lin ◽  
Aizhu Ye ◽  
Jinpiao Lin ◽  
Can Liu ◽  
Jinlan Huang ◽  
...  
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Clinical Outcomes ◽  
Hepatitis B Surface Antigen ◽  
Surrogate Marker ◽  
Diagnostic Value ◽  
Hbv Dna ◽  
Hbv Cccdna ◽  
B Virus ◽  
Intrahepatic Hbv

ABSTRACT Pregenomic RNA (pgRNA) is a direct transcription product of hepatitis B virus (HBV) covalently closed circular DNA (cccDNA), and it plays important roles in viral genome amplification and replication. This study was designed to investigate whether serum pgRNA is a strong alternative marker for reflecting HBV cccDNA levels and to analyze the correlation between serum pgRNA, serum HBV DNA, and hepatitis B surface antigen (HBsAg). A total of 400 HBV-infected patients who received nucleos(t)ide analog (NA) therapy with different clinical outcomes were involved in this research. Case groups included asymptomatic hepatitis B virus carrier (ASC), chronic hepatitis B (CHB), liver cirrhosis (LC), and hepatocellular carcinoma (HCC) patients, with 100 patients in each group. The results showed that the levels of HBV pgRNA had significant differences between these 4 groups. Serum pgRNA levels correlated well with serum HBV DNA and HBsAg levels (HBV pgRNA levels versus HBV DNA levels, r = 0.58, P < 0.001; HBV pgRNA levels versus HBsAg levels, r = 0.47, P < 0.001). In addition, we focused on the 108 HBV-infected patients with HBV DNA levels of <500 IU/ml; it was surprising to find that in 17.57% (13/74) of cases, HBV pgRNA could be detected even when the HBV DNA level was below 20 IU/ml. In conclusion, HBV pgRNA levels in serum can be a surrogate marker for intrahepatic HBV cccDNA compared with serum HBV DNA and HBsAg. The detection of serum HBV pgRNA levels may provide a reference for clinical monitoring of cccDNA levels and the selection of appropriate timing for discontinuing antiviral therapy, especially when HBV DNA levels are below the detection limit.

scholarly journals Hepatocyte Endoplasmic Reticulum Stress Inhibits Hepatitis B Virus Secretion and Delays Intracellular Hepatitis B Virus Clearance After Entecavir Treatment

2021 ◽  
Vol 7 ◽  
Author(s):  
Huan Chen ◽  
Maoyuan Mu ◽  
Qichuan Liu ◽  
Han Hu ◽  
Caiyun Tian ◽  
...  
Keyword(s):  
Endoplasmic Reticulum ◽  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Er Stress ◽  
Western Blotting ◽  
Hbv Dna ◽  
Translation Initiation Factor ◽  
Enzyme Linked Immunosorbent Assay ◽  
Hbv Replication ◽  
B Virus

Background: The aim of this study was to explore the effects of endoplasmic reticulum (ER) stress on hepatitis B virus (HBV) replication and the antiviral effect of entecavir (ETV).Methods: Thapsigargin (TG) and stearic acid (SA) were used to induce ER stress in HepG2.2.15 cells and HepAD38 cells that contained an integrated HBV genome, while ETV was used to inhibit HBV replication. The expression levels of glucose-regulated protein 78 (GRP78) and phosphorylated eukaryotic translation initiation factor 2 subunit alpha (p-eIF2α) were measured by western blotting. Intracellular HBV DNA was determined by qPCR; HBsAg by western blotting; HBV RNA by real-time RT-qPCR; HBsAg and HBeAg in supernatants by enzyme-linked immunosorbent assay (ELISA); and HBV DNA in supernatants by qPCR.Results: TG and SA induced ER stress in HepG2.2.15 cells and HepAD38 cells from 12 to 48 h post treatment. However, 4-phenylbutyric acid (PBA) partly alleviated the TG-induced ER stress. Moreover, TG inhibited HBsAg, HBeAg, and HBV DNA secretion from 12 to 48 h, while different concentrations of SA inhibited HBsAg and HBV DNA secretion at 48 h. TG promoted intracellular HBV DNA and HBsAg accumulation and the transcription of the HBV 3.5-kb mRNA and S mRNA. PBA treatment restored the secretion of HBsAg and HBV DNA. Finally, ER stress accelerated extracellular HBV DNA clearance but delayed intracellular HBV DNA clearance after ETV treatment.Conclusions: Hepatocyte ER stress promoted intracellular HBV DNA and HBsAg accumulation by inhibiting their secretion. Our study also suggested that hepatocyte ER stress delayed intracellular HBV DNA clearance after ETV treatment.

scholarly journals Replenishment of Hepatitis B Virus cccDNA Pool Is Restricted by Baseline Expression of Host Restriction Factors In Vitro

2019 ◽  
Vol 7 (11) ◽  
pp. 533 ◽  
Author(s):  
Sergey Brezgin ◽  
Anastasiia Kostyusheva ◽  
Ekaterina Bayurova ◽  
Ilya Gordeychuk ◽  
Maria Isaguliants ◽  
...  
Keyword(s):  
Dna Damage ◽  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Real Time ◽  
Real Time Pcr ◽  
Hbv Replication ◽  
Hbv Cccdna ◽  
B Virus ◽  
Infected Cells ◽  
Cell Cycling

Background: Covalently closed circular DNA (cccDNA) of hepatitis B virus (HBV) is the major cause of viral persistence in patients with chronic HBV infection. Understanding the mechanisms underlying stability and persistence of HBV cccDNA in hepatocytes is critical for developing novel therapeutics and managing chronic hepatitis B. In this study, we observed an unexpected increase in HBV cccDNA levels upon suppression of transcription by de novo DNA methyltransferase DNMT3A and uncovered additional mechanisms potentially involved in HBV cccDNA maintenance. Methods: HBV-expressing cell lines were transfected with a DNMT3A-expressing plasmid. Real-time PCR and HBsAg assays were used to assess the HBV replication rate. Cell cycling was analyzed by fluorescent cell sorting. CRISPR/Cas9 was utilized to abrogate expression of APOBEC3A and APOBEC3B. Alterations in the expression of target genes were measured by real-time PCR. Results: Similar to previous studies, HBV replication induced DNMT3A expression, which in turn, led to reduced HBV transcription but elevated HBV cccDNA levels (4- to 6-fold increase). Increased levels of HBV cccDNA were not related to cell cycling, as DNMT3A accelerated proliferation of infected cells and could not contribute to HBV cccDNA expansion by arresting cells in a quiescent state. At the same time, DNMT3A suppressed transcription of innate immunity factors including cytidine deaminases APOBEC3A and APOBEC3B. CRISPR/Cas9-mediated silencing of APOBEC3A and APOBEC3B transcription had minor effects on HBV transcription, but significantly increased HBV cccDNA levels, similar to DNMT3A. In an attempt to further analyze the detrimental effects of HBV and DNMT3A on infected cells, we visualized γ-H2AX foci and demonstrated that HBV inflicts and DNMT3A aggravates DNA damage, possibly by downregulating DNA damage response factors. Additionally, suppression of HBV replication by DNMT3A may be related to reduced ATM/ATR expression. Conclusion: Formation and maintenance of HBV cccDNA pools may be partially suppressed by the baseline expression of host inhibitory factors including APOBEC3A and APOBEC3B. HBV inflicts DNA damage both directly and by inducing DNMT3A expression.

scholarly journals Rebound of Hepatitis B Virus Replication in HepG2 Cells after Cessation of Antiviral Treatment

2002 ◽  
Vol 76 (16) ◽  
pp. 8148-8160 ◽  
Author(s):  
Ayman M. Abdelhamed ◽  
Colleen M. Kelley ◽  
Thomas G. Miller ◽  
Phillip A. Furman ◽  
Harriet C. Isom
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Drug Treatment ◽  
Time Course ◽  
Antiviral Treatment ◽  
Recombinant Baculovirus ◽  
Antiviral Agent ◽  
Hbv Dna ◽  
Hbv Replication ◽  
B Virus

ABSTRACT Treatment of patients with lamivudine (3TC) results in loss of detectable levels of hepatitis B virus (HBV) DNA from serum; however, the relapse rate, with regard to both reappearance of virus in the bloodstream and hepatic inflammation, is high when therapy is terminated. Although the rebound observed in patients has also been seen in animal hepadnavirus models, rebound has not been analyzed in an in vitro cell culture system. In this study, we used the HBV recombinant baculovirus/HepG2 system to measure the time course of antiviral agent-mediated loss of HBV replication as well as the time course and magnitude of HBV production after release from antiviral treatment. Because of the sensitivity of the system, it was possible to measure secreted virions, intracellular replicative intermediates, and nuclear non-protein-bound HBV DNA and separately analyze individual species of DNA, such as single-stranded HBV DNA compared to the double-stranded form and relaxed circular compared to covalently closed circular HBV DNA. We first determined that HBV replication in the HBV recombinant baculovirus/HepG2 system could proceed for at least 35 days, with a 30-day plateau level of replication, making it possible to study antiviral agent-mediated loss of HBV followed by rebound after cessation of drug treatment. All HBV DNA species decreased in a time-dependent fashion following antiviral treatment, but the magnitude of decline differed for each HBV DNA species, with the covalently closed circular form of HBV DNA being the most resistant to drug therapy. When drug treatment ceased, HBV DNA species reappeared with a pattern that recapitulated the initiation of replication, but with a different time course.

scholarly journals Strong and Selective Inhibitors of Hepatitis B Virus Replication among Novel N4-Hydroxy- and 5-Methyl-β-l-Deoxycytidine Analogues

2007 ◽  
Vol 51 (7) ◽  
pp. 2523-2530 ◽  
Author(s):  
E. Matthes ◽  
A. Funk ◽  
I. Krahn ◽  
K. Gaertner ◽  
M. von Janta-Lipinski ◽  
...  
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Inhibitory Concentration ◽  
Hbv Dna ◽  
Selective Inhibitor ◽  
Effective Concentration ◽  
Active Inhibitor ◽  
Hbv Replication ◽  
B Virus

ABSTRACT Novel N4-hydroxy- and 5-methyl-modified β-l-deoxycytidine analogues were synthesized and evaluated as anti-hepatitis B virus (HBV) agents. Their in vitro efficiencies were investigated in HepG2.2.15 cells stably transfected with HBV. β-l-2′,3′-Didehydro-2′,3′-dideoxy-N4-hydroxycytidine (β-l-Hyd4C) was most effective in reducing secreted HBV DNA (50% effective concentration [EC50], 0.03 μM), followed by β-l-2′,3′-dideoxy-3′-thia-N4-hydroxycytidine (EC50, 0.51 μM), β-l-2′,3′-dideoxy-N4-hydroxycytidine (EC50, 0.55 μM), and β-l-5-methyl-2′-deoxycytidine (EC50, 0.9 μM). The inhibition of the presumed target, the HBV DNA polymerase, by the triphosphates of some of the β-l-cytidine derivatives was also assessed. In accordance with the cell culture data, β-l-Hyd4C triphosphate was the most active inhibitor, with a 50% inhibitory concentration of 0.21 μM. The cytotoxicities of some of the 4-NHOH-modified β-l-nucleosides were dramatically lower than those of the corresponding cytidine analogues with the unmodified 4-NH2 group. The 50% cytotoxic concentrations for β-l-Hyd4C in HepG2 and HL-60 cells were 2,500 μM and 3,500 μM, respectively. In summary, our results demonstrate that at least β-l-Hyd4C can be recommended as a highly efficient and extremely selective inhibitor of HBV replication for further investigations.

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