Search

Abstract Background Chronic hepatitis B virus (HBV) infection is a serious global health concern, with an increased incidence and risk of developing cirrhosis and hepatocellular carcinoma (HCC). Patients chronically infected with HBV are likely to experience chronic oxidative stress, leading to mitochondrial dysfunction. Photobiomodulation is induced by the absorption of low-level laser therapy (LLLT) with a red or infrared laser by cytochrome C oxidase enzyme, resulting in mitochondrial photoactivation. Although it is widely used in clinical practice, the use of LLL as adjuvant therapy for persistent HBV infection is uncommon. This study aimed to investigate the effect of LLLT dosage from 2 J/cm2 to 10 J/cm2 of red diode laser (650 nm) on both hepatoma cell lines (HepG2.2.15 [integrated HBV genome stable cell model] and non-integrated HepG2), with a subsequent impact on HBVsvp production. Methods The present study evaluated the effects of different fluences of low-level laser therapy (LLLT) irradiation on various aspects of hepatoma cell behavior, including morphology, viability, ultrastructure, and its impact on HBVsvp synthesis. Results In response to LLLT irradiation, we observed a considerable reduction in viability, proliferation, and HBVsvp production in both hepatoma cell lines HepG2.2.15 and HepG2. Ultrastructural modification of mitochondria and nuclear membranes: This effect was dose, cell type, and time-dependent. Conclusions The use of LLLT may be a promising therapy for HCC and HBV patients by reducing cell proliferation, HBVsvp production, and altering mitochondrial and nuclear structure involved in cellular death inducers. Further research is required to explore its clinical application.

Background: Chronic hepatitis B virus (HBV) infection is a serious global health concern, with an increased incidence and risk of developing cirrhosis and hepatocellular carcinoma (HCC). Patients chronically infected with HBV are likely to experience chronic oxidative stress, leading to mitochondrial dysfunction. Photobiomodulation is induced by the absorption of low-level laser therapy (LLLT) with a red or infrared laser by cytochrome C oxidase enzyme, resulting in mitochondrial photoactivation. Although it is widely used in clinical practice, the use of LLL as adjuvant therapy for persistent HBV infection is uncommon. This study aimed to investigate the effect of LLLT dosage from 2 J/cm2 to 10 J/cm2 of red diode laser (650 nm) on both hepatoma cell lines (HepG2.2.15 [integrated HBV genome stable cell model] and non-integrated HepG2), with a subsequent impact on HBVsvp production. Methods: The present study evaluated the effects of different fluences of low-level laser therapy (LLLT) irradiation on various aspects of hepatoma cell behavior, including morphology, viability, ultrastructure, and its impact on HBVsvp synthesis. Results: In response to LLLT irradiation, we observed a considerable reduction in viability, proliferation, and HBVsvp production in both hepatoma cell lines HepG2.2.15 and HepG2. Ultrastructural modification of mitochondria and nuclear membranes: This effect was dose, cell type, and time-dependent. Conclusions: The use of LLLT may be a promising therapy for HCC and HBV patients by reducing cell proliferation, HBVsvp production, and altering mitochondrial and nuclear structure involved in cellular death inducers. Further research is required to explore its clinical application. [ABSTRACT FROM AUTHOR]

A series of novel 1,2,3‐triazole‐linked hexopyranosyl mono/double‐headed pyrimidine nucleosides from D‐glucose was synthesized by Cu(I)‐mediated [3+2] cycloaddition reactions (CuAAC) of mono/diazido 2,6‐anhydro‐glucoheptitol and propynylated pyrimidines in good yields. It was observed that all the four synthesized pyrimidine nucleosides were found to be non‐cytotoxic upto 500 μM concentration. The 1,2,3‐triazole‐linked hexopyranosyl mono/double‐headed pyrimidine nucleosides have shown significant suppression of Hepatitis B surface antigen (HBsAg) and Hepatitis B e‐antigen (HBeAg). Amongst all the synthesized compounds, nucleoside dimer 1‐[1‐(6′‐deoxy‐6′‐(4‐(1‐methyluracil)‐1,2,3‐triazol‐1‐yl)‐β‐D‐glucopyranosyl methyl)‐1,2,3‐triazol‐4‐yl]methyl‐uracil was found to be more effective against HBeAg. In the suppression of viral DNA level, all the four synthesized nucleoside analogues were comparable to known drug Entecavir (ETV) with IC50 value in the range of 8.39 μM–18.58 μM and are two folds significant as compared to control. [ABSTRACT FROM AUTHOR]

Background and Aims: Hepatitis B virus (HBV) infection is a major risk factor for cirrhosis and liver cancer, and its treatment continues to be difficult. We previously demonstrated that a dopamine analog inhibited the packaging of pregenomic RNA into capsids. The present study aimed to determine the effect of dopamine on the expressions of hepatitis B virus surface and e antigens (HBsAg and HBeAg, respectively) and to elucidate the underlying mechanism., Methods: We used dopamine-treated HBV-infected HepG2.2.15 and NTCP-G2 cells to monitor HBsAg and HBeAg expression levels. We analyzed interferon-stimulated gene 15 (ISG15) expression in dopamine-treated cells. We knocked down ISG15 and then monitored HBsAg and HBeAg expression levels. We analyzed the expression of Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway factors in dopamine-treated cells. We used dopamine hydrochloride-treated adeno-associated virus/HBV-infected mouse model to evaluate HBV DNA, HBsAg, and HBeAg expression. HBV virus was collected from HepAD38.7 cell culture medium., Results: Dopamine inhibited HBsAg and HBeAg expression and upregulated ISG15 expression in HepG2.2.15 and HepG2-NTCP cell lines. ISG15 knockdown increased HBsAg and HBeAg expression in HepG2.2.15 cells. Dopamine-treated cells activated the JAK/STAT pathway, which upregulated ISG15 expression. In the adeno-associated virus-HBV murine infection model, dopamine downregulated HBsAg and HBeAg expression and activated the JAK-STAT/ISG15 axis., Conclusions: Dopamine inhibits the expression of HBsAg and HBeAg by activating the JAK/STAT pathway and upregulating ISG15 expression., Competing Interests: The authors have no conflict of interest related to this publication., (© 2024 Authors.)

The present study was proposed to model full-length HBV-RT and investigate the intermolecular interactions of known inhibitor and libraries of phytocompounds to probe the potential natural leads by in silico and in vitro studies. Homology modeling of RT was performed by Phyre2 and Modeller and virtual screening of ligands implemented through POAP pipeline. Molecular dynamics (MD) simulation (100 ns) and MM-GBSA calculations were performed using Schrodinger Desmond and Prime, respectively. Phytocompounds probable host protein targets gene set pathway enrichment and network analysis were executed by KEGG database and Cytoscape software. Prioritized plant extracts/enriched fraction LC-MS analysis was performed and along with pure compound, RT inhibitory activity, time-dependent HBsAg and HBeAg secretion, and intracellular HBV DNA, and pgRNA by qRT-PCR was performed in HepG2.2.15 cell line. Among the screened chemical library of 268 phytocompounds from 18 medicinal plants, 15 molecules from Terminalia chebula (6), Bidens pilosa (5), and Centella asiatica (4)) were identified as potential inhibitors of YMDD and RT1 motif of HBV-RT. MD simulation demonstrated stable interactions of 15 phytocompounds with HBV-RT, of which 1,2,3,4,6-Pentagalloyl Glucose (PGG) was identified as lead molecule. Out of 15 compounds, 11 were predicted to modulate 39 proteins and 15 molecular pathways associated with HBV infection. TCN and TCW (500 µg/mL) showed potent RT inhibition, decreased intracellular HBV DNA, and pgRNA, and time-dependent inhibition of HBsAg and HBeAg levels compared to PGG and Tenofovir Disoproxil Fumarate. We propose that the identified lead molecules from T. chebula as promising and cost-effective moieties for the management of HBV infection.Communicated by Ramaswamy H. Sarma.

As a highly efficient delivery system, lentiviral vectors (LVs) have become a powerful tool to assess the antiviral efficacy of RNA drugs such as short hairpin RNA (shRNA) and decoys. Furthermore, recent advanced systems allow controlled expression of the effector RNA via coexpression of a tetracycline/doxycycline (DOX) responsive repressor (tTR-KRAB). Herein, this system was utilized to assess the antiviral effects of LV-encoded shRNAs targeting three conserved regions on the pregenomic RNA of hepatitis B virus (HBV), namely the region coding for the reverse transcriptase (RT) domain of the viral polymerase (LV-HBV-shRNA1), the core promoter (CP; LV-HBV-shRNA2), and the direct repeat 1 (DR1; LV-HBV-shRNA3). Transduction of just the LV-HBV-shRNA vectors into the stably HBV expressing HepG2.2.15 cell line showed significant reductions in secreted HBsAg and HBeAg, intracellular HBcAg as well as HBV RNA and DNA replicative intermediates for all vectors, however, most pronouncedly for the DR1-targeting shRNA3. The corresponding vector was therefore applied in the DOX-controlled system. Notably, strong interference with HBV replication was found in the presence of the inducer DOX whereas the antiviral effect was essentially ablated in its absence; hence, the silencing effect of the shRNA and consequently HBV replication could be strictly regulated by DOX. This newly established system may therefore provide a valuable platform to study the antiviral efficacy of RNA drugs against HBV in a regulated manner, and even be applicable in vivo. [ABSTRACT FROM AUTHOR]

Abstract: Natural killer (NK) cells and cytolytic T lymphocytes (CTL) have been implicated as important effectors of antiviral defense. We previously isolated a novel antibacterial polypeptide, which was identified as high mobility group nucleosomal-binding domain 2 (HMGN2), from human mononuclear leukocytes. This study examined the antiviral activity of HMGN2 against human hepatitis virus B. HMGN2 was isolated and purified from the acid soluble proteins of the human THP-1 cell line, and identified by mass spectrum, Western blot and antibacterial assay. The hepatitis B virus (HBV)-transfected HepG2.2.15 cell line was used in the in vitro assay system. In the range of 1–100μg/ml HMGN2, no cytotoxicity for HepG2.2.15 cells was detected by MTT assay. When incubated with HMGN2 at 1–100μg/ml for 72 or 144h, there was a significant reduction in hepatitis B e antigen (HBeAg) and hepatitis B surface antigen (HBsAg) expression, which were detected by ELISA, and a significant reduction in HBV DNA copies, which was determined by the real time quantitative PCR, in the supernatant of HepG2.2.15 cells. Northern and Southern blot analysis also showed that the levels of the HBV 3.5kb and the 2.4/2.1kb mRNA species and HBV replicative intermediate DNA were significantly reduced in the HMGN2-treated HepG2.2.15 cells. These results indicated that HMGN2 protein could markedly inhibit HBV protein expression and replication in vitro. [Copyright &y& Elsevier]