anti-HBV Activity Research Articles

Hepatitis B virus infection among men who have sex with men and transgender women living with or at risk for HIV: a cross sectional study in Abuja and Lagos, Nigeria

BackgroundDespite the development of a safe and efficacious hepatitis B vaccine in 1982, the hepatitis B virus (HBV) remains a public health burden in sub-Saharan Africa. Due to shared risk factors for virus acquisition, men who have sex with men (MSM) and transgender women (TGW) living with HIV are at increased risk of HBV. We estimated the prevalence of HBV and associated factors for MSM and TGW living with or without HIV in Nigeria.MethodsSince March 2013, TRUST/RV368 has recruited MSM and TGW in Abuja and Lagos, Nigeria using respondent driven sampling. Participants with HIV diagnosis, enrollment as of June 2015, and available plasma were selected for a cross-sectional study and retrospectively tested for hepatitis B surface antigen and HBV DNA. Logistic regression models were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for factors associated with prevalent HBV infection.ResultsA total of 717 MSM and TGW had a median age of 25 years (interquartile range [IQR]: 21–27), 5% self-reported HBV vaccination, 61% were living with HIV, 10% had prevalent HBV infection and 6% were HIV-HBV co-infected. HIV mono-infected as compared to HIV-HBV co-infected had a higher median CD4 T cell count [425 (IQR: 284–541) vs. 345 (IQR: 164–363) cells/mm3, p = 0.03] and a lower median HIV RNA viral load [4.2 (IQR: 2.3–4.9) vs. 4.7 (IQR: 3.9–5.4) log10copies/mL, p < 0.01]. The only factor independently associated with HBV was self-report of condomless sex at last anal intercourse (OR: 2.2, 95% CI: 1.3, 3.6). HIV infection was not independently associated with HBV (OR: 1.0, 95% CI: 0.7–1.6).ConclusionHBV prevalence was moderately high but did not differ by HIV in this cohort of MSM and TGW. Recent condomless sex was associated with elevated HBV risk, reinforcing the need to increase communication and education on condom use among key populations in Nigeria. Evaluating use of concurrent HIV antiretroviral therapy with anti-HBV activity may confirm the attenuated HBV prevalence for those living with HIV.

E3 ubiquitin ligase TRIM21 restricts hepatitis B virus replication by targeting HBx for proteasomal degradation

As a cytosol ubiquitin ligase and antibody receptor, Tripartite motif-containing 21 (TRIM21) has been reported to mediate the restriction of hepatitis B virus (HBV) through an HBx-antibody-dependent intracellular neutralization (ADIN) mechanism. However, whether TRIM21 limits HBV replication by targeting viral proteins remains unclarified. In this study, we demonstrate that TRIM21 inhibits HBV gene transcription and replication in HBV plasmid transfected and HBV-infected hepatoma cells. RING and PRY-SPRY domains are involved in this activity. TRIM21 interacts with HBx protein and targets HBx for ubiquitination and proteasomal degradation, leading to impaired HBx-mediated degradation of structural maintenance of chromosomes 6 (Smc6) and suppression of HBV replication. TRIM21 fails to restrict the replication of an HBx-deficient HBV. And knock-down of Smc6 largely impairs the anti-HBV activity of TRIM21 in HepG2 cells. In a hydrodynamic injection (HDI)-based HBV mouse model, we confirm an in vivo anti-HBV and anti-HBx therapeutic effect of TRIM21 by over-expression or knocking-out strategy. Our findings reveal a novel mechanism that TRIM21 restricts HBV replication through targeting HBx-Smc5/6 pathway, which may have an implication in the future TRIM21-based therapeutic application.

Combined Curcuma longa and Cratoxylum formosum Extracts Possess Anti-liver Cancer and Anti-HBV Activities in HepG2.2.15

Background: Curcuma longa Linn. and Cratoxylum formosum have been consumed as the Thai traditional medicine for curing liver diseases. However, biological effects from a combination of C. longa and C. formosum have not been investigated. Objective: This study focused to investigate the effects of combined extracts on anti-liver cancer activity, anti-Hepatitis B virus (HBV) activity and alteration of miRNA expression, including their effects on p53 and NF-κB protein expressions. Methods: The cytotoxicity effects of hot water extract on liver cancer cells were examined by using the MTT assay. Annexin V assay and Western blot analysis were conducted to investigate the effects of plant extracts on the apoptosis pathway and cellular protein expressions. Finally, the expression of HBV genes and miRNA expressions were evaluated by using a quantitative real-time PCR. Results: The cell viability assay indicated that 400 μg/mL of combined C. longa and C. formosum extracts significantly inhibited different liver cancer cell lines without affecting a normal cell (Vero). The combined extracts could induce liver cancer cell death via the apoptosis pathway by up-regulating p53 expression while down-regulating NF-κB expression. Moreover, 150 μg/mL of the combined extract specifically suppressed HBx gene expression in liver cancer cells that stably express HBV proteins. However, 150 μg/mL of the combined extract had no effect on miR-34a and miR-199a/b expressions. Conclusion: This study firstly reported anti-liver cancer and anti-HBV activities of the combined C. longa and C. formosum extracts.

A novel piperazine derivative that targets hepatitis B surface antigen effectively inhibits tenofovir resistant hepatitis B virus

Chronic hepatitis B virus (HBV) infection is a global problem. The loss of hepatitis B surface antigen (HBsAg) in serum is a therapeutic end point. Prolonged therapy with nucleoside/nucleotide analogues targeting the HBV-polymerase may lead to resistance and rarely results in the loss of HBsAg. Therefore, inhibitors targeting HBsAg may have potential therapeutic applications. Here, we used computational virtual screening, docking, and molecular dynamics simulations to identify potential small molecule inhibitors against HBsAg. After screening a million molecules from ZINC database, we identified small molecules with potential anti-HBV activity. Subsequently, cytotoxicity profiles and anti-HBV activities of these small molecules were tested using a widely used cell culture model for HBV. We identified a small molecule (ZINC20451377) which binds to HBsAg with high affinity, with a KD of 65.3 nM, as determined by Surface Plasmon Resonance spectroscopy. Notably, the small molecule inhibited HBsAg production and hepatitis B virion secretion (10 μM) at low micromolar concentrations and was also efficacious against a HBV quadruple mutant (CYEI mutant) resistant to tenofovir. We conclude that this small molecule exhibits strong anti-HBV properties and merits further testing.

Safety, tolerability, pharmacokinetics, and pharmacodynamics of oral JNJ-64794964, a TLR-7 agonist, in healthy adults.

This Phase I, two-part, first-in-human study assessed safety/tolerability and pharmacokinetics/pharmacodynamics of single-ascending doses (SAD) and multiple doses (MD) of the oral toll-like receptor-7 agonist, JNJ-64794964 (JNJ-4964) in healthy adults. In the SAD phase, participants received JNJ-4964 0.2 (N = 6), 0.6 (N = 6), 1.25 (N = 8) or 1.8mg (N = 6) or placebo (N = 2/dose cohort) in a fasted state. Food effect was evaluated for the 1.25mg cohort following ≥6weeks washout. In the MD phase, participants received JNJ-4964 1.25mg (N = 6) or placebo (N = 2) weekly (fasted) for 4weeks. Participants were followed-up for 4weeks. No serious adverse events (AEs) occurred. 10/34 (SAD) and 5/8 (MD) participants reported mild-to-moderate (≤Grade 2), transient, reversible AEs possibly related to JNJ-4964. Five (SAD) participants had fever/flu-like AEs, coinciding with interferon-α serum levels ≥100 pg/mL and lymphopenia (<1 × 109/L), between 24-48h after dosing and resolving approximately 96h after dosing. One participant (MD) had an asymptomatic Grade 1 AE of retinal exudates (cotton wool spots) during follow-up, resolving 6weeks after observation. JNJ-4964 exhibited dose-proportional pharmacokinetics, with rapid absorption (tmax 0.5-0.75h) and distribution, and a long terminal half-life (150-591h). Overall, no significant differences in JNJ-4964 pharmacokinetic parameters were observed in the fed versus fasted state. JNJ-4964 dose-dependently and transiently induced cytokines with potential anti-HBV activity, including interferon-α, IP-10, IL-1 RA, and/or MCP-1, and interferon-stimulated genes (ISG15, MX1, and OAS1) in serum. In healthy adults, JNJ-4964 was generally well-tolerated, exhibited dose-proportional pharmacokinetics and induced cytokines/ISGs, with possible anti-HBV activity.

Design of Dimeric Bile Acid Derivatives as Potent and Selective Human NTCP Inhibitors.

Dimeric bile acid derivatives (DBADs) were developed and tested for their anti-HBV and anti-HDV activities as sodium taurocholate cotransporting polypeptide (NTCP) inhibitors. DBADs exhibited strong and persistent potency of NTCP inhibition, whereas diverse linkers and constitutions showed distinct inhibition features. Motif aa157-165 on NTCP was shown to be a possible binding site of DBADs; therefore, we determined DBADs' selectivity among NTCPs from different species. A cyclized DBAD scaffold DBA-41 exhibited a high affinity to human NTCP (hNTCP). Intraperitoneal administration of DBA-41 to hNTCP-tg mice induced serum total bile acid elevation. DBA-41 may serve as a biological tool to study NTCP physiological function.

Development of a cellular high-content, immunofluorescent HBV core assay to identify novel capsid assembly modulators that induce the formation of aberrant HBV core structures

Hepatitis B Virus (HBV) core protein has multiple functions in the viral life cycle and is an attractive target for new anti-viral therapies. Capsid assembly modulators (CAMs) target the core protein and induce the formation of either morphologically normal (CAM-N) or aberrant structures (CAM-A), both devoid of genomic material. To date a diverse family of CAM-N chemotypes has been identified, but in contrast, described CAM-As are based on the heteroaryldihydropyrimidine (HAP) scaffold. We used the HBV-inducible HepG2.117 cell line with immunofluorescent labeling of HBV core to develop and validate a cellular high-content image-based assay where aggregated core structures are identified using image analysis spot texture features. Treatment with HAPs led to a dose- and time-dependent formation of aggregated core appearing as dot-like structures in the cytoplasm and nucleus. By combining a biochemical and cellular screening approach, a compound was identified as a novel non-HAP scaffold able to induce dose-dependent formation of aberrant core structures, which was confirmed by electron microscopy and native gel electrophoresis. This compound displayed anti-HBV activity in HepG2.117 cells, providing proof-of-concept for our screening approach. We believe our combined biochemical and cellular high-content screening method will aid in expanding the range of CAM-A chemotypes.

The Functional and Antiviral Activity of Interferon Alpha-Inducible IFI6 Against Hepatitis B Virus Replication and Gene Expression.

Hepatitis B virus is an enveloped DNA virus, that infects more than three hundred and sixty million people worldwide and leads to severe chronic liver diseases. Interferon-alpha inducible protein 6 (IFI6) is an IFN-stimulated gene (ISG) whose expression is highly regulated by the stimulation of type I IFN-alpha that restricts various kinds of virus infections by targeting different stages of the viral life cycle. This study aims to investigate the antiviral activity of IFI6 against HBV replication and gene expression. The IFI6 was highly induced by the stimulation of IFN-α in hepatoma cells. The overexpression of IFI6 inhibited while knockdown of IFI6 elevated replication and gene expression of HBV in HepG2 cells. Further study determined that IFI6 inhibited HBV replication by reducing EnhII/Cp of the HBV without affecting liver enriched transcription factors that have significant importance in regulating HBV enhancer activity. Furthermore, deletion mutation of EnhII/Cp and CHIP analysis revealed 100 bps (1715-1815 nt) putative sites involved in IFI6 mediated inhibition of HBV. Detailed analysis with EMSA demonstrated that 1715-1770 nt of EnhII/Cp was specifically involved in binding with IFI6 and restricted EnhII/Cp promoter activity. Moreover, IFI6 was localized mainly inside the nucleus to involve in the anti-HBV activity of IFI6. In vivo analysis based on the hydrodynamic injection of IFI6 expression plasmid along with HBV revealed significant inhibition of HBV DNA replication and gene expression. Overall, our results suggested a novel mechanism of IFI6 mediated HBV regulation that could develop potential therapeutics for efficient HBV infection treatment.

Antiviral Activity of Interferon Alpha-Inducible Protein 27 Against Hepatitis B Virus Gene Expression and Replication.

Despite the availability of effective vaccines, hepatitis B virus (HBV) is still a major health issue, and approximately 350 million people have been chronically infected with HBV throughout the world. Interferons (IFNs) are the key molecules in the innate immune response that restrict several kinds of viral infections via the induction of hundreds of IFN-stimulated genes (ISGs). The objective of this study was to confirm if interferon alpha-inducible protein 27 (IFI27) as an ISG could inhibit HBV gene expression and DNA replication both in cell culture and in a mouse model. In human hepatoma cells, IFI27 was highly induced by the stimulation of IFN-alpha (IFN-α), and it potentiated the anti-HBV activity. The overexpression of IFI27 inhibited, while its silencing enhanced the HBV replication in HepG2 cell. However, the knocking out of IFI27 in HepG2 cells robustly increases the formation of viral DNA, RNA, and proteins. Detailed mechanistic analysis of the HBV genome showed that a sequence [nucleotide (nt) 1715–1815] of the EnhII/Cp promoter was solely responsible for viral inhibition. Similarly, the hydrodynamic injection of IFI27 expression constructs along with the HBV genome into mice resulted in a significant reduction in viral gene expression and DNA replication. In summary, our studies suggested that IFI27 contributed a vital role in HBV gene expression and replication and IFI27 may be a potential antiviral agent for the treatment of HBV.

Anti-HBV Activities of Polysaccharides from Thais clavigera (Küster) by In Vitro and In Vivo Study.

Hepatitis B virus (HBV) infection remains a major global health problem. It is therefore imperative to develop drugs for anti-hepatitis B with high-efficiency and low toxicity. Attracted by the observations and evidence that the symptoms of some patients from the Southern Fujian, China, suffering from hepatitis B were alleviated after daily eating an edible marine mollusk, Thais clavigera (Küster 1860) (TCK). Water-soluble polysaccharide from TCK (TCKP1) was isolated and characterized. The anti-HBV activity of TCKP1 and its regulatory pathway were investigated on both HepG2.2.15 cell line and HBV transgenic mice. The data obtained from in vitro studies showed that TCKP1 significantly enhanced the production of IFN-α, and reduced the level of HBV antigens and HBV DNA in the supernatants of HepG2.2.15 cells in a dose-dependent manner with low cytotoxicity. The result of the study on the HBV transgenic mice further revealed that TCKP1 significantly decreased the level of transaminases, HBsAg, HBeAg, and HBV DNA in the serum, as well as HBsAg, HBeAg, HBV DNA, and HBV RNA in the liver of HBV transgenic (HBV-Tg) mice. Furthermore, TCKP1 exhibited equivalent inhibitory effect with the positive control tenofovir alafenamide (TAF) on the markers above except for HBV DNA even in low dosage in a mouse model. However, the TCKP1 high-dose group displayed stronger inhibition of transaminases and liver HBsAg, HBeAg, and HBV RNA when compared with those of TAF. Meanwhile, inflammation of the liver was, by pathological observation, relieved in a dose-dependent manner after being treated with TCKP1. In addition, elevated levels of interleukin-12 (IL-12) and interferon γ (IFN-γ), and reduced level of interleukin-4 (IL-4) in the serum were observed, indicating that the anti-HBV effect of TCKP1 was achieved by potentiating immunocyte function and regulating the balance of Th1/Th2 cytokines.

3D human liver organoids: An in vitro platform to investigate HBV infection, replication and liver tumorigenesis.

Hepatitis B Virus (HBV) infection is a leading cause of chronic liver cirrhosis and hepatocellular carcinoma (HCC) with an estimated 400 million people infected worldwide. The precise molecular mechanisms underlying HBV replication and tumorigenesis have remained largely uncharacterized due to the lack of a primary cell model to study HBV, a virus that exhibits stringent host species and cell-type specificity. Organoid technology has recently emerged as a powerful tool to investigate human diseases in a primary 3D cell-culture system that maintains the organisation and functionality of the tissue of origin. In this review, we describe the utilisation of human liver organoid platforms to study HBV. We first present the different categories of liver organoids and their demonstrated ability to support the complete HBV replication cycle. We then discuss the potential applications of liver organoids in investigating HBV infection and replication, related tumorigenesis and novel HBV-directed therapies. Liver organoids can be genetically modified, patient-derived, expanded and biobanked, thereby serving as a clinically-relevant, human, primary cell-derived platform to investigate HBV. Finally, we provide insights into the future applications of this powerful technology in the context of HBV-infection and HCC.

Dichondra repens J.R.Forst. and G.Forst.: A Review of Its Traditional Uses, Chemistry, Pharmacology, Toxicology and Applications.

Ethnopharmacology relevance: Dichondra repens J.R.Forst. and G.Forst (DRF; Convolvulaceae, called Matijin in Chinese), has been traditionally used to treat jaundice, bacillary dysentery, urinary tract infection, edema, contusions, and strains and sprains based on traditional Chinese medicine (TCM) concepts. Aim of study: This paper intends to provide a comprehensive and critical analysis of research on DRF focusing on a relationship between traditional uses and pharmacological effects, evaluating the therapeutic potential of this plant. Methods: Relevant data on DRF were retrieved from available databases. Results: The heat-clearing and detoxifying, and removing the phlegm and turbid urine effects of DRF are linked to its anti-hepatitis B virus (HBV), anti-inflammatory, and hepatoprotective activities. Especially, the hepatoprotective effects of DRF are mainly based on anti-HBV activities of phenylalanine dipeptides Matijin-Su (MTS) and its derivatives derived from this plant. Further, a phase I anti-HBV clinical trial of a candidate compound named bentysrepinine (Y101, Chinese name Tifentai) has been completed. Also, anti-tumor, analgesic, and antibacterial properties have been reported in the extracts and compounds from DRF. Although pharmacy, pharmacodynamics, toxicology, and pharmacokinetics of bentysrepinine have been systemically reported, no studies have reported chemistry, safety, pharmacology of other compounds or extracts systemically. Conclusion: Phenylalanine dipeptide compounds are main components and MTS is a characteristic substance of DRF. The main pharmacological effect of DRF is anti-HBV activity, which is coherent with the traditional use of this plant in China. Except bentysrepinine, few studies have been conducted on toxicities of the extracts or compounds from DRF. Thus, it is still necessary to evaluate safety, chemistry, pharmacology of the extracts or compounds from DRF regarding the link between traditional uses and modern applications before the future clinical trials. Bacterial sepsis, cholecystitis and tumors may be prior therapeutic targets of this plant in the future.

Functional Comparison of Interferon-α Subtypes Reveals Potent Hepatitis B Virus Suppression by a Concerted Action of Interferon-α and Interferon-γ Signaling.

Interferon (IFN)-α, composed of numerous subtypes, plays a crucial role in immune defense. As the most studied subtype, IFN-α2 has been used for treating chronic hepatitis B virus (HBV) infection, with advantages of finite treatment duration and sustained virologic response, but its efficacy remains relatively low. This study aimed to screen for IFN-α subtypes with the highest anti-HBV potency and to characterize mechanisms of IFN-α-mediated HBV restriction. Using cell culture-based HBV infection systems and a human-liver chimeric mouse model, IFN-α subtype-mediated antiviral response and signaling activation were comprehensively analyzed. IFN-α14 was identified as the most effective subtype in suppression of HBV covalently closed circular DNA transcription and HBV e antigen/HBV surface antigen production, with median inhibitory concentration values approximately 100-fold lower than those of the conventional IFN-α2. IFN-α14 alone elicited IFN-α and IFN-γ signaling crosstalk in a manner similar to the combined use of IFN-α2 and IFN-γ, inducing multiple potent antiviral effectors, which synergistically restricted HBV replication. Guanylate binding protein 5, one of the most differentially expressed genes between IFN-α14-treated and IFN-α2-treated liver cells, was identified as an HBV restriction factor. A strong IFN-α-IFN-α receptor subunit 1 interaction determines the anti-HBV activity of IFN-α. The in vivo anti-HBV activity of IFN-α14 and treatment-related transcriptional patterns were further confirmed, and few adverse effects were observed. A concerted IFN-α and IFN-γ response in liver, which could be efficiently elicited by IFN-α subtype 14, is associated with potent HBV suppression. These data deepen the understanding of the divergent activities of IFN-α subtypes and the mechanism underlying the synergism between IFN-α and IFN-γ signaling, with implications for improved IFN therapy and HBV curative strategies.

Geranylgeranylacetone decreases the production of hepatitis B virus-related antigen by comprehensive downregulation of mRNA transcription activity.

Elimination of hepatitis B virus (HBV) is infrequently achieved with current therapies. Therefore, more effective anti-HBV therapy is needed. We previously reported that geranylgeranylacetone (GGA) showed anti-hepatitis C virus activity in human hepatoma cells. In this study, we examined the anti-HBV activity of GGA. We used HepG2.2.15.7 cells, PXB cells infected with HBV, Huh7 cells transfected with linear HBV, and PLC/PRF/5 cells as HBV-infected hepatocyte models. After GGA treatment, HBV-related antigen was measured by chemiluminescent immunoassay. HBV-related mRNA was examined by Northern blot. cccDNA and endoplasmic reticulum stress markers were measured by real-time polymerase chain reaction. The activities of HBV promoters and enhancer regions were examined using luciferase vectors. After GGA treatment, hepatitis B surface antigen and hepatitis B e antigen secretion was decreased in all HBV-infected hepatocyte models. HBV-related mRNA was also decreased by GGA treatment, although cccDNA levels were not affected. Additionally, the activity of HBV S1 and S2 promoter region and Enhancer 1/Enhancer 2/core promoter region was reduced by GGA treatment. The mRNA expression of the main transcription factors, hepatocyte nuclear factor 3 and 4 and CCAAT/enhancer binding protein, was also decreased. Further, the expression levels of endoplasmic reticulum stress markers were increased by GGA treatment, which reflected the change in HBV-related antigen secretion. Geranylgeranylacetone treatment reduces HBV-related protein levels by suppressing comprehensive downregulation of HBV promoter and enhancer activity, which might be caused by decreased hepatic transcription factor expression. GGA treatment may enhance anti-HBV effects in combination with other therapies.

New Insights on Long-Term Hepatitis B Virus Responses in HIV-Hepatitis B virus Co-infected Patients: Implications for Antiretroviral Management in Hepatitis B virus-Endemic Settings.

WHO treatment guidelines recommend tenofovir plus lamivudine or emtricitabine as the nucleoside reverse transcriptase inhibitor backbone in first-line regimens for HIV-infected adults. Lamivudine alone is not recommended, because of the risk of hepatitis B virus (HBV) resistance. We studied HBV responses in a large cohort of co-infected patients in a resource-limited setting. Clinical centers in Uganda and Zimbabwe. DART was a randomized trial of monitoring practices in HIV-infected adults starting antiretroviral therapy. Baseline samples were tested retrospectively for HBV serological markers and HBV DNA. Longitudinal HBV DNA testing at 48 weeks and the last available sample before HBV-relevant modification of antiretroviral therapy was performed on patients with detectable HBV DNA at baseline. Two hundred twenty-four hepatitis B surface antigen-positive patients were followed for up to 4.8 years. Of the drugs with anti-HBV activity, 166 were prescribed lamivudine-tenofovir and 58 lamivudine alone. Ninety-eight percent (96/98) patients with baseline HBV DNA <6 log10 IU/mL achieved viral suppression at 48 weeks (HBV DNA <48 IU/mL), regardless of regimen, compared with 50%(26/52) for HBV DNA >6 log10 IU/mL. Of the 83 patients suppressed at 48 weeks and with follow-up data, only 7(8%) experienced viral rebound (range 200-3460 IU/mL). Of the 20 patients not suppressed at 48 weeks and with follow-up data, HBV DNA levels generally declined with lamivudine-tenofovir, but increased with lamivudine alone. Alanine transaminase flares were not observed in any patient who experienced viral rebound. The suppressive effect of lamivudine alone was highly durable (up to 5 years) in HIV-HBV co-infected patients with baseline HBV DNA <6 log10 IU/mL. It may be feasible to develop stratified approaches using lamivudine as the only drug with anti-HBV activity.

Introduction of a cyano group at the 2-position of an (R,S)-3-hydroxy-2-(phosphonomethoxy)propyl (HPMP) derivative of thymine elicits selective anti-HBV activity

The substantial impact of acyclic nucleoside phosphonates (ANPs) on human medicine encourages the synthesis of new ANP analogues with a potentially differentiated antiviral spectrum. Herein, we demonstrate the functionalization of the 2-position of the (R,S)-3-hydroxy-2-(phosphonomethoxy)propyl side-chain of an inactive ANP with a polar cyano group to generate a thymine analogue with selective inhibition of hepatitis B virus (HBV) replication (SI > 302; EC50 = 0.33 μM), without significant antiretroviral activity. These findings suggest new strategies to synthesize unique ANPs with a targeted antiviral profile.

Өсімдік көздерінен оқшауланған хлор атомы бар сесквитерпеноидтар

Сесквитерпенді лактондар екіншілік метаболиттердің ең үлкен тобын құрайтын өсімдіктер әлемінде кеңінен таралған құрылымы және қасиеттері тұрғысынан қызықтыратын қосылыстар болып табылады. Сесквитерпенді лактондар жоғары биобелсенділігімен, соның ішінде қабынуға, бактерияға, зеңге, безгекке, лейшманиозға қарсы белсенділікке, сондай-ақ ісікке қарсы және цитоуыттылық әсерлерге ие болуымен ерекшеленеді. Гепатит В вирусына қарсы белсенділігі бар өкілдері анықталған. Олардың негізінде перспективалы медициналық препараттар немесе дәрі-дәрмектер алынуы айтарлықтай назар аудартады. Бұл қысқа шолу мақалада галоген атомы бар сесквитерпенді лактондар туралы мәліметтер жиналды. Жүргізілген зерттеулер бойынша табиғатта кездесетін галоген атомы бар қосылыстарда әдетте хлор атомы болатыны байқалады. Құрылымдық ерекшеліктеріне келетін болсақ, табиғи көздерден бөлінген галогенді сесквитерпенді лактондардың көпшілігі гвайан құрылымды екендігі анықталды, секо-гвайанолид және гермакранолид түрінде де кездеседі. Сонымен қатар олардың биологиялық белсенділігі, атап айтқанда зеңге қарсы, қабынуға қарсы, қатерлі ісікке қарсы, антирадикалды, меланогенезді және тирозиназа белсенділіктері, цитоуыттылығы анықталды.

Identification of a novel long-acting 4’-modified nucleoside reverse transcriptase inhibitor against HBV

While certain nucleos(t)ide reverse transcriptase inhibitors (NRTIs) are efficacious in treating HBV infection, their effects are yet to be optimized and the emergence of NRTI-resistant HBV variants is an issue because of the requirement for lifelong treatment. The development of agents that more profoundly suppress wild-type and drug-resistant HBVs, and that have a long-acting effect, are crucial to improve patient outcomes. Herein, we synthesized a novel long-acting 4'-modified NRTI termed E-CFCP. We tested its anti-HBV activity invitro, before evaluating its anti-HBV activity in HBV-infected human-liver-chimeric mice (PXB-mice). E-CFCP's long-acting features and E-CFCP-triphosphate's interactions with the HBV reverse transcriptase (HBV-RT) were examined. E-CFCP potently blocked HBVWTD1 production (IC50qPCR_cell=1.8 nM) in HepG2.2.15 cells and HBVWTC2 (IC50SB_cell=0.7 nM), entecavir (ETV)-resistant HBVETV-RL180M/S202G/M204V (IC50SB_cell=77.5 nM), and adefovir-resistant HBVADV-RA181T/N236T production (IC50SB_cell=14.1 nM) in Huh7 cells. E-CFCP profoundly inhibited intracellular HBV DNA production to below the detection limit, but ETV and tenofovir alafenamide (TAF) failed to do so. E-CFCP also showed less toxicity than ETV and TAF. E-CFCP better penetrated hepatocytes and was better tri-phosphorylated; E-CFCP-triphosphate persisted intracellularly for longer than ETV-triphosphate. Once-daily peroral E-CFCP administration over 2 weeks (0.02~0.2 mg/kg/day) reduced HBVWTC2-viremia by 2-3 logs in PXB-mice without significant toxicities and the reduction persisted over 1-3 weeks following treatment cessation, suggesting once-weekly dosing capabilities. E-CFCP also reduced HBVETV-RL180M/S202G/M204V-viremia by 2 logs over 2 weeks, while ETV completely failed to reduce HBVETV-RL180M/S202G/M204V-viremia. E-CFCP's 4'-cyano and fluorine interact with both HBVWT-RT and HBVETV-RL180M/S202G-M204 -RT via Van der Waals and polar forces, being important for E-CFCP-triphosphate's interactions and anti-HBV potency. E-CFCP represents the first reported potential long-acting NRTI with potent activity against wild-type and treatment-resistant HBV. Although there are currently effective treatment options for HBV, treatment-resistant variants and the need for lifelong therapy pose a significant challenge. Therefore, the development of new treatment options is crucial to improve outcomes and quality of life. Herein, we report preclinical evidence showing that the anti-HBV agent, E-CFCP, has potent activity against wild-type and treatment-resistant variants. In addition, once-weekly oral dosing may be possible, which is preferrable to the current daily dosing regimens.

Neddylation inhibitor MLN4924 has anti-HBV activity via modulating the ERK-HNF1α-C/EBPα-HNF4α axis.

Hepatitis B virus (HBV) infection is a major public health problem. The high levels of HBV DNA and HBsAg are positively associated with the development of secondary liver diseases, including hepatocellular carcinoma (HCC). Current treatment with nucleos(t)ide analogues mainly reduces viral DNA, but has minimal, if any, inhibitory effect on the viral antigen. Although IFN reduces both HBV DNA and HBsAg, the serious associated side effects limit its use in clinic. Thus, there is an urgent demanding for novel anti‐HBV therapy. In our study, viral parameters were determined in the supernatant of HepG2.2.15 cells, HBV‐expressing Huh7 and HepG2 cells which transfected with HBV plasmids and in the serum of HBV mouse models with hydrodynamic injection of pAAV‐HBV1.2 plasmid. RT‐qPCR and Southern blot were performed to detect 35kb mRNA and cccDNA. RT‐qPCR, Luciferase assay and Western blot were used to determine anti‐HBV effects of MLN4924 and the underlying mechanisms. We found that treatment with MLN4924, the first‐in‐class neddylation inhibitor currently in several phase II clinical trials for anti‐cancer application, effectively suppressed production of HBV DNA, HBsAg, 3.5kb HBV RNA as well as cccDNA. Mechanistically, MLN4924 blocks cullin neddylation and activates ERK to suppress the expression of several transcription factors required for HBV replication, including HNF1α, C/EBPα and HNF4α, leading to an effective blockage in the production of cccDNA and HBV antigen. Our study revealed that neddylation inhibitor MLN4924 has impressive anti‐HBV activity by inhibiting HBV replication, thus providing sound rationale for future MLN4924 clinical trial as a novel anti‐HBV therapy.

Activation of the Liver X Receptor Pathway Inhibits HBV Replication in Primary Human Hepatocytes.

Hepatitis B virus (HBV) infection is ranked among the top health priorities worldwide. Accumulating evidence suggests that HBV infection and replication are closely associated with liver metabolism. The liver X receptors (LXRs), which belong to the superfamily of nuclear hormone receptors, are important physiological regulators of lipid and cholesterol metabolism. However, the association between the LXR pathway and HBV infection remains largely unclear. In this study, the antiviral activity of LXR agonists was investigated using multiple HBV cellular models. We observed that in HBV-infected primary human hepatocytes (PHHs), synthetic LXR agonists (T0901317, GW3965, and LXR-623), but not an LXR antagonist (SR9238), potently inhibited HBV replication and gene expression, as demonstrated by substantial reductions in viral RNA, DNA, and antigen production following agonist treatment. However, covalently closed circular DNA (cccDNA) levels were not significantly reduced by the agonists. In addition, no rebound in viral replication was observed after treatment withdrawal, indicating a long-lasting inhibitory effect. These results suggest that LXR agonists decrease the transcriptional activity of cccDNA. In contrast, no significant anti-HBV effect was observed in HepG2-derived cell lines. Interestingly, LXR agonist treatment strongly reduced cholesterol 7α-hydroxylase 1 (CYP7A1) mRNA levels. Knockdown of CYP7A1 gene expression with small interfering RNA inhibited HBV activity in PHHs, suggesting CYP7A1 as a potential factor contributing to the antiviral effects of LXR agonists. We found that activation of the LXR pathway with synthetic LXR agonists could elicit potent anti-HBV activity in PHHs, possibly through sustained suppression of cccDNA transcription. Our work highlights the therapeutic potential of targeting the LXR pathway for the treatment of chronic HBV infection.