Search Results (142)

Recently, essential rose oils and rose products have gained increasing importance in both the cosmetic and food industries, as well as in the composition of medicinal products. We investigated the in vitro antiviral activity of essential oil and floral water from Rosa damascena Mill against herpes simplex virus type 1 (HSV-1) infection in rabbit retinal cells (RRCs). The composition of the main chemical components in the rose essential oil was determined by means of gas chromatographic analysis. The effect on the viral replication cycle was determined using the cytopathic effect (CPE) inhibition assay. The virucidal activity, the effect on the adsorption stage of the virus to the host cell, and the protective effect on healthy cells were evaluated using the endpoint dilution method. The effects were determined as deviation in the viral titer, Δlg, for the treated cells from the one for the untreated viral control. The identified main active components of rose oil are geraniol (28.73%), citronellol (21.50%), nonadecane (13.13%), nerol (5.51%), heneicosane (4.87%), nonadecene (3.93), heptadecane (2.29), farnesol (2.11%), tricosane (1.29%), eicosane (1.01%), and eugenol (0.85%). The results demonstrated that both rose products do not have a significant effect on the virus replication but directly affect the viral particles and reduce the viral titer by Δlg = 3.25 for floral water and by Δlg = 3.0 for essential oil. Significant inhibition of the viral adsorption stage was also observed, leading to a decrease in the viral titers by Δlg = 2.25 for floral water and by Δlg = 2.0 for essential oil. When pretreating healthy cells with rose products, both samples significantly protected them from subsequent infection with HSV-1. This protective effect was more pronounced for the oil (Δlg = 2.5) compared to the one for the floral water (Δlg = 2.0). We used the in silico molecular docking method to gain insight into the mechanism of hindrance of viral adsorption by the main rose oil compounds (geraniol, citronellol, nerol). These components targeted the HSV-1 gD interaction surface with nectin-1 and HVEM (Herpesvirus Entry Mediator) host cell receptors, at N-, C-ends, and N-end, respectively. These findings could provide a structural framework for further development of anti-HSV-1 therapeutics. Full article

Schizophrenia is a challenging multifactorial neuropsychiatric disease that involves interactions between genetic susceptibility and environmental insults. Increasing evidence implicates viral infections as significant environmental contributors, particularly during sensitive neurodevelopmental periods. This review synthesises current findings on the viral hypothesis of schizophrenia, encompassing a wide array of neurotropic viruses, including influenza viruses, herpesviruses (HSV-1 and 2, CMV, VZV, EBV, HHV-6 and 8), hepatitis B and C viruses, HIV, HERVs, HTLV, Zika virus, BoDV, coronaviruses (including SARS-CoV-2), and others. These pathogens can contribute to schizophrenia through mechanisms such as direct microinvasion, persistent central nervous system infection, immune-mediated neuroinflammation, molecular mimicry, and the disturbance of the blood–brain barrier. Prenatal exposure to viral infections can trigger maternal immune activation, resulting in cytokine-mediated alterations in the neurological development of the foetus that persist into adulthood. Genetic studies highlight the role of immune-related loci, including major histocompatibility complex polymorphisms, in modulating susceptibility to infection and neurodevelopmental outcomes. Clinical data also support the “mild encephalitis” hypothesis, suggesting that a subset of schizophrenia cases involve low-grade chronic neuroinflammation. Although antipsychotics have some immunomodulatory effects, adjunctive anti-inflammatory therapies show promise, particularly in treatment-resistant cases. Despite compelling associations, pathogen-specific links remain inconsistent, emphasising the need for longitudinal studies and integrative approaches such as viromics to unravel causal relationships. This review supports a “multi-hit” model in which viral infections interfere with hereditary and immunological susceptibilities, enhancing schizophrenia risk. Elucidating these virus–immune–brain interactions may facilitate the discovery of biomarkers, targeted prevention, and novel therapeutic strategies for schizophrenia. Full article

Background/Objectives: Simplexvirus humanalpha1 (HSV-1) can cause herpetic keratitis, which is the most common cause of infectious blindness in developed countries. Some patients can develop toxicity or resistance to available treatments and may require keratoplasty. Methods: As an alternative therapy, the CRISPR/Cas9 anti-HSV-1 activity was assessed in an experimental model of BALB/c mice. Results: The results showed that the viral load in the eyes of mice inoculated with HSV-1 at 10⁷ PFU/mL was 4.5 ± 0.2 log₁₀ copies/mL. In contrast, mice inoculated with 10⁹ PFU/mL exhibited a high viral load of 8.1 ± 0.4 log₁₀ copies/mL. The detection of HSV-1 DNA and lesions in the eye was consistent with the viral inoculum of the infection. Next, antiviral activity showed that 200 ng/µL of CRISPR/Cas9 reduced the viral load by 2 logs (p ≤ 0.0001), as well as the lesion scores, compared to the untreated group. Conclusions: Together, the data suggest that CRISPR/Cas9 could be investigated as an alternative therapy for ocular herpes. Full article

Herpes simplex virus type 1 (HSV-1) is a widespread pathogen responsible for recurrent infections, primarily affecting the skin and mucous membranes. With the aim of targeting both the viral infection and the associated inflammatory response, biotechnologically produced Lavandula angustifolia Miller (L. angustifolia) extract, rich in rosmarinic acid, was incorporated into liposomal formulations intended for topical application. Lavender is known for its strong anti-inflammatory, antioxidant, wound-healing, and antiviral properties. However, its low stability under certain conditions limits its therapeutic potential. Four different formulations were developed: conventional liposomes, glycerosomes, hyalurosomes, and glycerohyalurosomes. The vesicles were characterized for size, stability, and entrapment efficiency. Glycerosomes were the smallest (~58 nm), while the other formulations ranged around 77 nm, all maintaining a highly negative surface charge, ensuring stability and reduced aggregation. Glycerol-containing formulations demonstrated superior stability over 12 months, while liposomes and hyalurosomes increased their size after only two months. Entrapment efficiency reached up to 100% for most vesicles, except for glycerohyalurosomes (~54%). In vitro studies on Normal Human Dermal Fibroblasts (NHDFs) demonstrated that all formulations were biocompatible and enhanced cell viability under oxidative stress. Glycerosomes, hyalurosomes, and glycerohyalurosomes exhibited significant anti-inflammatory activity by reducing MMP-1 and IL-6 levels in LPS-stimulated fibroblasts. Furthermore, these preliminary results highlighted promising antiviral activity against HSV-1 of the obtained formulations, particularly when applied during or post-infection. Overall, these phospholipid vesicles offer a dual therapeutic approach, combining antioxidant, anti-inflammatory, and antiviral effects, positioning them as promising candidates for the treatment of HSV-induced skin lesions and related inflammatory conditions. Full article

Herpes simplex virus type 1 (HSV-1) is a globally prevalent pathogen that can infect a variety of animal species as well as humans. However, existing antiviral therapies are constrained in their capacity to effectively target viral latency and prevent recurrent infections. Antimicrobial peptides (AMPs), particularly cathelicidins, as part of innate immune system have demonstrated broad-spectrum efficacy against viral pathogens. In this study, four peptides derived from Elephas maximus cathelicidin EM were designed and optimized (EM-1 to EM-4). We identified low toxicity peptide derivatives through hemolytic and cytotoxicity assays, quantified their anti-HSV-1 activity by determining IC₅₀. Antiviral mechanisms were investigated using RT-qPCR and antiviral efficacy was ultimately validated in C57BL/6J mice through viral load quantification in brain, lung, and heart tissues. Our findings revealed that EM-1 significantly inhibited HSV-1 replication in U251 cells. In a murine footpad inoculation model, EM-1 administration substantially reduced viral loads and alleviated inflammatory responses. Histological assessment demonstrated that EM-1 treatment mitigated HSV-1 induced tissue damage in infected mice. We also found that EM-1 exerted its antiviral effects by upregulating the expression of interferon-gamma and its downstream genes, such as ISG15 and MX1. These findings indicated that EM-1 is a dual function peptide that inhibits replication of HSV-1 as well as enhances host antiviral immunity. Collectively, this study highlights the therapeutic potential of elephant cathelicidin derived peptides in antiviral development. Full article

Clinacanthus nutans (Burm.f.) Lindau is a Southeast Asian medicinal plant traditionally used for treating skin inflammation and infections. This study evaluated its wound-healing potential through anti-inflammatory, cytoprotective, and antiviral mechanisms. HPLC-DAD analysis identified schaftoside as the major flavonoid in the 95% ethanolic leaf extract. In the lipopolysaccharide (LPS)-stimulated murine macrophage cell line (RAW 264.7), both C. nutans extract (5 and 50 μg/mL) and its flavonoid schaftoside (5 and 20 μg/mL) significantly downregulated the expression of pro-inflammatory genes, including cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and prostaglandin E₂ (PGE₂), under both pre-treatment and post-treatment conditions. ELISA confirmed dose-dependent inhibition of human COX-2 enzymatic activity, reaching up to 99.3% with the extract and 86.9% with schaftoside. In the endothelial cell models (CCL-209), the extract exhibited low cytotoxicity and effectively protected cells from LPS-induced apoptosis, preserving vascular integrity critical to tissue regeneration. Antiviral assays demonstrated suppression of HSV-2 replication, particularly during early infection, which may help prevent infection-related delays in wound healing. Collectively, these findings suggest that C. nutans and schaftoside promote wound repair by attenuating inflammatory responses, supporting endothelial survival, and controlling viral reactivation. These multifunctional properties highlight their potential as natural therapeutic agents for enhancing wound-healing outcomes. Full article

Immune function declines with age, leading to increased vulnerability of the elderly to viral infectious pathogens. The mechanisms by which aging negatively impacts the innate and adaptive immune system, leading to enhanced susceptibility to respiratory viral pathogens, remain incompletely understood. In the present study, we utilized a mouse model of infection with herpes simplex virus type 1 (HSV-1), a virus that can infect the lungs and lead to pneumonia, a rare but serious health concern in the elderly. Following intranasal inoculation of young (6 weeks), adult (36 weeks), and aged mice (68 weeks) with HSV-1 (KOS strain) we: (i) compared the local and systemic immune responses to infection in young, adult, and aged mice, and (ii) correlated the level and type of immune responses to protection against HSV-1 infection and disease. Compared to young and adult mice, aged mice displayed: (i) increased activation of epithelial cells with a decreased expression of TLR3; (ii) increased activation of dendritic cells with increased expression of MHC-I, MHC-II, and CD80/86; (iii) decreased production of type-I interferons; (iv) delayed production of anti-inflammatory cytokines and chemokines in the lungs; and (v) impairment frequencies of functional HSV-specific CD107+IFN-γ+CD8+ T cells associated with the increased incidence of viral infection and disease. These findings suggest that age-related impairments in innate and adaptive immune responses may exacerbate respiratory viral infections and disease in the elderly. Full article

Respiratory viruses can cause life-threatening conditions such as sepsis and acute respiratory distress syndrome. However, vaccines and effective antivirals are available for only a limited number of infections. The majority of approved antivirals are direct-acting agents, which target viral proteins essential for infection. Unfortunately, mutations have already emerged that confer resistance to these antivirals. In addition, there is an urgent need for broad-spectrum antivirals to address the unpredictable emergence of new viruses with pandemic potential. One promising strategy involves modulating the innate immune response and cellular signaling. Imiquimod, a Toll-like receptor 7 (TLR7) agonist, has shown efficacy in murine models of influenza and respiratory syncytial virus (RSV). Additionally, it demonstrates antiviral activity against herpes simplex virus type 1 (HSV-1) and RSV independent of the TLR7/nuclear factor kappa B (NF-κB) pathway, with protein kinase A (PKA) as a crucial downstream effector. In this study, we demonstrate that imiquimod exhibits concentration-dependent antiviral activity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and canine coronavirus (CCoV) in epithelial cells, underscoring its broad-spectrum action against coronaviruses. Moreover, its anti-coronavirus effect appears to be independent of the TLR/NF-κB and PKA/exchange protein directly activated by cyclic adenosine monophosphate (EPAC) pathways and may instead be linked to the activation of the mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) pathway. The ability of imiquimod to inhibit coronavirus replication via the MEK/ERK pathway, coupled with its immunomodulatory properties, highlights its potential as a broad-spectrum antiviral. Full article

Cyvirus cyprinidallo3, also known as Cyprinid herpesvirus 3 (CyHV-3), is a common pathogen of koi and common carp (Cyprinus carpio). Infection of CyHV-3 can lead to high mortality in fry under 4 months of age. CyHV-3 can become latent in recovered fish, and latent CyHV-3 can reactivate under stress conditions and spread the virus. Reactivation of CyHV-3 can also lead to mortality and diseases in latently infected fish. No effective drugs are available to prevent CyHV-3 infection or reactivation from latency. There is a need for the discovery of anti-CyHV-3 drugs. Harmine (HAR) and harmaline (HAL) are β-carboline alkaloids found in the medicinal plant Peganum harmala with antiviral activities against many viruses, including HSV. Here, HAL was evaluated against CyHV-3 infection in vitro and in vivo, respectively. Immediately after a one-hour infection exposure of ~1000 FPU/plate or ~500 PFU/plate, cells treated with 5 µM HAL for 2 h can block nearly 50% or 90% plaque formation in vitro. Only around 50% inhibition was observed in cells treated with the common anti-herpesvirus drug acyclovir (ACV) at 10 or 20 µM for 2 h following 1 h post-infection of ~500 PFU/plate. Cells treated with 10 µM HAL for 30 min, 60 min, 2 h, and 6 h can reduce 60%, 65%, 85.5%, and 85% CyHV-3 replication in vitro, respectively. HAL at 20 µM is still effective against CyHV-3 DNA replication and virion production when the treatment started at 3 and 5 days post-infection for 1 or 2 h, respectively. HAL under 50 µM has little toxicity to cells treated for 24 h. Immersion treatment with 10 µM HAL for 3–4 h daily within the first 5 days post-infection can increase the survival of fry by 60%. In addition, IM injection of HAL at 20 µM can reduce the rate of CyHV-3 reactivation induced by heat stress in latently infected koi. This study demonstrated that HAL could potentially be used to prevent CyHV-3 infection or reactivation from latency. Full article

Background/Objectives: This study aims to gain insights into the antimicrobial and antiherpetic activity of hyperforin-rich Hypericum perforatum L. (HP) extract using nanostructured lipid carriers (NLCs) as delivery platforms. Methods: Two established NLC specimens, comprising glyceryl behenate and almond oil or borage oil, and their extract-loaded counterparts (HP-NLCs) were utilized. Their minimal bactericidal/fungicidal concentrations (MBC; MFC) were investigated against Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 10145, Klebsiella pneumoniae ATCC 10031, and Candida albicans ATCC 10231. The anti-herpesvirus (HSV-1) potential was evaluated concerning antiviral and virucidal activity and impact on viral adsorption. Results: The borage oil-based extract-loaded nanodispersion (HP-NLC2) exhibited pronounced microbicidal activity against S. aureus (MBC 6.3 mg/mL), K. pneumoniae (MBC 97.7 µg/mL), and C. albicans (MFC < 48.8 µg/mL), unlike the almond oil-containing sample (HP-NLC1), which showed only weak inhibition of the fungal growth. HP-NLC2 was found to be less cytotoxic and to suppress HSV-1 replication slightly more than HP-NLC1, but generally, the effects were weak. Neither the empty lipid nanoparticles nor the HP extract-loaded carriers expressed activity against E. coli, P. aeruginosa, the HSV-1 extracellular virions, or viral adhesion. Conclusions: It could be concluded that both HP-NLC samples revealed only minor antiherpetic potential of the hyperforin-rich extract, but HP-NLC2 demonstrated significant antibacterial and antimycotic activity. Therefore, the latter was featured as a more convenient HP-carrier system for nano-designed dermal pharmaceutical formulations. Such a thorough investigation of hyperforin-determined anti-HSV-1 effects and antibacterial and antimycotic properties, being the first of its kind, contributes to the fundamental knowledge of HP and reveals new perspectives for the utilization, limitations, and therapeutic designation of its non-polar components. Full article

Herpes simplex viruses (HSV-1 and HSV-2), which can be transmitted both orally and sexually, cause lifelong morbidity and in some cases, meningitis and encephalitis. While both the passive transfer of neutralizing antibodies and placental transfer of anti-HSV monoclonal antibodies (Mabs) have shown therapeutic promise in animal models, clinical trials have yet to identify approved immunotherapeutics for herpes infection. Here, we present strategies for the generation of recombinant bispecific antibodies (BsAbs) that target different domains of glycoprotein D (gD), crucial for HSV entry, that have the potential to outperform the effect of individual Mabs to curb herpes infection. Specifically, we selected three pairs of Mabs from our extensive panel for BsAb design and production based on their binding site and ability to block virus entry. Actual binding of BsAbs to gD and epitope availability on gD after BsAb binding were characterized using surface plasmon resonance (SPR) and inhibition by IgG Fab fragments generated from selected Mabs. While one BsAb exhibited an additive effect similar to that observed using a combination of the Mabs utilized for its generation, two showed antagonistic effects, suggesting that the simultaneous engagement of two epitopes or selective binding to one affected their activity against HSV. One BsAb (DL11/1D3) targeting the binding site for both nectin-1 and HVEM receptors demonstrated synergistic inhibitory activity against HSV, outperforming the effect of the individual antibodies. Recombinant DL11/1D3 antibody variants, in which the size of one or both paratopes was decreased to single chains (scFv-Fc), highlighted differences in potency depending on antibody size and format. We propose that BsAbs to individual glycoproteins offer a potential avenue for herpes therapeutics, but their design, mechanism of action, antibody format, and epitope engagement require careful consideration of structure for optimal efficacy. Full article

Pulicaria species are used as herbal medicine and in the preparation of decoctions in several Asian and African regions. Among them, the plant Pulicaria burchardii is known for its medicinal properties, but comprehensive studies on its biological activity are still limited. This study examined the properties of the essential oil (EO) extracted by P. burchiardii and collected in Morocco during the flowering period. The focus was on its antimicrobial, anti-germinative, antioxidant, and antiviral activities, with the aim of evaluating its potential use in food preservation and beyond. The EO was subjected to various analyses to determine its chemical composition and biological efficacy. Specifically, GCMS and NMR analyses revealed that the EO is rich in oxygenated sesquiterpenes (72.59%), with 1-oxo-bisabolone being the predominant component (65.09%). The antimicrobial activity was tested against various Gram-positive and Gram-negative bacteria, demonstrating a significant inhibition of bacterial growth, particularly against Bacillus subtilis (MIC value of 0.6 mg/mL). The anti-germinative property was evaluated on spores of B. subtilis and other bacilli, such as Bacillus cereus, revealing a notable ability to prevent germination. For antiviral activity, the EO was tested against several pathogenic viruses including SARS-CoV-2 and HSV-1, showing an effective broad-spectrum reduction in viral replication in vitro. This study demonstrated that P. burchardii essential oil had excellent antibacterial and antiviral capabilities. The future challenge will focus mainly on the principal compound, 1-oxo-bisabolone, to demonstrate its real effectiveness as an antibacterial and/or antiviral. Full article

Herpes viruses are highly contagious agents affecting all classes of vertebrates, thus causing serious health, social, and economic losses. Within the One Health concept, novel therapeutics are extensively studied for both veterinary and human control and management of the infection, but the optimal strategy has not been invented yet. Lactic acid bacteria are key components of the microbiome that are known to play a protective role against pathogens as one of the proposed mechanisms involves compounds released from their metabolic activity. Previously, we reported the anti-herpes effect of postmetabolites isolated from Lactobacilli, and here, we confirm the inhibitory properties of another nine products against the phylogenetically distant human Herpes simplex virus-1 (HSV-1) and fish Koi Herpes virus (KHV) in cell cultures. Cytotoxicity, cytopathic effect inhibition, virucidal effect, the influence on the adsorption stage of the virus to the cells, as well as the protective effect of the postmetabolites on healthy cells were evaluated. The inhibitory effect was more pronounced against HSV-1 than against KHV at all studied viral cycle stages. Regarding the intracellular replicative steps, samples S7, S8, and S9 (Mix group) isolated from Ligilactobacillus salivarius (vaginal strain) demonstrated the most distinct effect with calculated selective indices (SIs) in the range between 69.4 and 77.8 against HSV-1, and from 62.2 to 68.4 against KHV. Bioactive metabolites from various LAB species significantly inhibit extracellular HSV-1 and, to a lesser extent, KHV virions. The blockage of viral adsorption to the host cells was remarkable, as recorded by a decrease in the viral titer with Δlg ≥ 5 in the Mix group for both herpes viruses. The remaining postmetabolites also significantly inhibited viral adsorption to varying degrees with Δlg ≥ 3. Most metabolites also exerted a protective effect on healthy MDBK and CCB cells to subsequent experimental viral infection. Our results reveal new horizons for the application of LAB and their postbiotic products in the prevention and treatment of herpes diseases. Full article

Herpes simplex virus type 1 (HSV-1) acyclovir (ACV) resistance is acquired by mutations in the viral thymidine kinase (TK) or DNA polymerase (DNApol) genes. We previously obtained an ACV-resistant clone (HSV-1_VZV_TK_clone α) by sequential passages of HSV-1_VZV-TK, a recombinant virus which lacked its endogenous TK activity and instead expressed the varicella-zoster virus (VZV) TK ectopically. HSV-1_VZV_TK_clone α had been generated using an HSV-1_BAC in the presence of increasing concentrations of ACV. The ACV-resistant clone bore normal TK and DNApol genes. Here, we deployed next-generation full-genome sequencing of HSV-1_VZV_TK_clone α and identified a single nucleotide substitution, resulting in a P597L missense mutation in the UL29 gene product, the ICP8 protein. Recombinant HSV-1 encoding a P597L ICP8 protein was generated, and its properties and ability to confer drug resistance were analyzed. No difference in virus growth and UL29 expression was observed between the mutant recombinant, the wild type, and a revertant mutant viral strain, and susceptibility tests of these strains to ACV and other drugs using Vero, HEL, and ARPE19 cells identified that the recombinant UL29 mutant virus was resistant only to ACV. These results indicate that ICP8 may be involved in the anti-herpesvirus drugs’ mechanism of action on HSV-1. Full article

It is estimated that nearly all individuals have been infected with herpesviruses, with herpes simplex virus type 1 (HSV-1) representing the most prevalent virus. In most cases, HSV-1 causes non-life-threatening skin damage in adults. However, in patients with compromised immune systems, it can cause serious diseases, including death. The situation is further complicated by the emergence of strains that are resistant to both traditional and novel antiviral drugs. It is, therefore, imperative that new methods of combating HSV-1 and other herpesviruses be developed without delay. CRISPR/Cas systems may prove an effective means of controlling herpesvirus infections. This review presents the current understanding of the underlying molecular mechanisms of HSV-1 infection and discusses four potential applications of CRISPR/Cas systems in the fight against HSV-1 infections. These include the search for viral and cellular genes that may serve as effective targets, the optimization of anti-HSV-1 activity of CRISPR/Cas systems in vivo, the development of CRISPR/Cas-based HSV-1 diagnostics, and the validation of HSV-1 drug resistance mutations. Full article