Search Results (153)

The discovery of antiviral agents is an important research area because the world is increasingly exposed to the risk of viral infectious diseases. Herpes simplex virus type 2 (HSV-2) causes globally prevalent sexually transmitted diseases, and numerous individuals are living with HSV-2. Influenza A virus (IAV) causes annual epidemics and occasional pandemics, attracting great concern in public health. In this study, antiviral activities against HSV-2 and IAV of 103 flavonoids were screened. The screening identified cirsilineol and apigenin as active against HSV-2, while cirsimaritin and hymenoxin displayed anti-IAV activity. These flavonoids have the potential to serve as therapeutic candidates for viral infectious diseases. Full article

Herpes simplex viruses (HSV-1 and HSV-2) are highly prevalent human pathogens that establish lifelong latency in sensory neurons, posing a persistent challenge to global public health. Their clinical manifestations range from mild, self-limiting orolabial lesions to severe, life-threatening conditions such as disseminated neonatal infections, focal encephalitis, and herpetic stromal keratitis, which can lead to irreversible corneal blindness. Beyond direct pathology, HSV-mediated genital ulcerative disease (GUD) significantly enhances mucosal susceptibility to HIV-1 and other sexually transmitted infections, amplifying co-infection risk and disease burden. Despite decades of clinical reliance on nucleoside analogues such as acyclovir, the therapeutic landscape has stagnated with rising antiviral resistance, toxicity associated with prolonged use, and the complete inability of current drugs to eliminate latency or prevent reactivation continue to undermine effective disease control. These persistent gaps underscore an urgent need for next-generation antivirals that operate through fundamentally new mechanisms. Marine ecosystems, the planet’s most chemically diverse environments, are providing an expanding repertoire of antiviral compounds with significant therapeutic promise. Recent discoveries reveal that marine-derived polysaccharides, sulfated glycans, peptides, alkaloids, and microbial metabolites exhibit remarkably potent and multi-targeted anti-HSV activities, disrupting viral attachment, fusion, replication, and egress, while also reshaping host antiviral immunity. Together, these agents showcase mechanisms and scaffolds entirely distinct from existing therapeutics. This review integrates emerging evidence on structural diversity, mechanistic breadth, and translational promise of marine natural products with anti-HSV activity. Collectively, these advances position marine-derived compounds as powerful, untapped scaffolds capable of reshaping the future of HSV therapeutics. Full article

The study focused on essential oils (EOs) of plant origin, which are of great interest to scientists in the context of medical applications due to their biological properties, such as antimicrobial, anti-inflammatory, antioxidant, and anticancer effects. The objective of the study was to determine chemical profiles and biological activities of the essential oils extracted from five mixtures (M1 [Thymus vulgaris, Ammi visnaga, Syzygium aromaticum, Citrus sinensis]; M2 [Thymus vulgaris, Ammi visnaga, Cinnamomum verum, Citrus sinensis]; M3 [Mentha pulegium, Lavandula angustifolia, Zingiber officinale, Citrus sinensis]; M4 [Mentha pulegium, Lavandula angustifolia, Cinnamomum verum, Citrus sinensis]; M5 [Ammi visnaga, Lavandula angustifolia, Zingiber officinale, Syzygium aromaticum]). Each mixture was derived from a blend of four selected plants used in traditional medicine in Mostaganem, Algeria. When selecting the best composition, the interactions between plant components were considered in terms of potential therapeutic benefits. The chemical compositions of the EO mixtures were analyzed using GC-MS. The acute toxicity of the EO mixtures was evaluated in vivo following oral administration. The sensitivity of the microorganisms to the EO mixtures was determined using the agar diffusion method. Virucidal testing was performed using the quantitative suspension method to determine virucidal activity, as described in the European standard for disinfectants used in the medical field. The antioxidant activity of the EO mixtures was evaluated using a model membrane system based on liposomes derived from soybean phosphatidylcholine. Chemopreventive activity was assessed in vitro using cell culture. The main compounds identified were carvacrol and thymol in M1; geranial, cinnamylaldehyde, and carvacrol in M2; pulegone and limonene in M3; geranial and cinnamylaldehyde and limonene in M4; and eugenol and caryophyllene in M5. The selection of the “best” blend depended on the biological activity deemed most critical for the specific application. Specifically, M3, M4, and M5 exhibited the strongest anti-HSV-1, anti-HAdV-5, and anticancer activity, respectively. In contrast, M1, a potent antioxidant, demonstrated the strongest antibacterial and anticancer activity. These results indicate that M1, M3, M4, and M5 EOs have promising applications in the pharmaceutical industry and medical research. Full article

Our previously discovered marine natural products, peniterphenyls A and E, exhibit superior anti-herpes simplex virus 1/2 (HSV 1/2) activity, probably via interference with virus adsorption and membrane fusion to host cells. Their clear mechanism mode still remains unresolved due to its limited availability from nature. This study establishes their first site-selective chemical total syntheses, affording peniterphenyls A and E in overall yields of 4.5% (over thirteen steps) and 2.3% (over twelve steps), respectively. A nucleophilic aromatic substitution (S_NAr) between compounds 4 and 5, and a direct C(sp²)–H/C(sp²)–H oxidative coupling using the Pd(TFA)₂/AgOAc catalyst system with a pivaloyl directing group conveniently furnishes the dibenzofuran core with good efficiency. Steric hindrance and substituent directing effects of arene govern the high site-selectivity of the Pd-catalyzed C(sp²)–H activation during furan formation. Featuring readily available materials and straightforward operations, this synthetic route provides convenient access to these bioactive natural products for further study. Full article

Mannose is a natural monosaccharide that plays a central role in host–pathogen interactions and has emerged as a versatile scaffold for designing anti-infective agents. This review summarizes recent advances in mannose-based glycoconjugates with antibacterial, antiviral, antifungal, and antiparasitic activity. In bacteria, FimH antagonists prevent Escherichia coli adhesion, while mannose-functionalized materials disrupt Pseudomonas and Burkholderia biofilms or enhance delivery of anti-tubercular drugs. In virology, mannose-containing dendrimers, glycopolymers, and nanoparticles inhibit HIV, SARS-CoV-2, Ebola, HPV, and HSV by targeting viral glycoproteins or blocking lectin-mediated transmission. Mannose-decorated vaccines and nanocarriers also show promise against fungal pathogens and parasites. Continued optimization of presented structures could lead to the promising candidates for clinically applicable therapies. Full article

Background/Objectives: Schizophrenia (SCH), bipolar disorder (BPD), and major depressive disorder (MDD) are increasingly viewed as neuroimmune disorders shaped by viral exposure and inflammation. Disorder-specific immunovirological profiles, however, remain poorly defined. Methods: In this cross-sectional study, we assessed Epstein–Barr Virus (EBV) and Herpes Simplex Virus type 1 (HSV-1) seropositivity and measured serum CRP, IL-6, and IL-1β in 708 participants: 110 with SCH, 121 with BPD, 135 with MDD, and 342 healthy controls (HC). Statistical analyses included Shapiro–Wilk tests for normality; Kruskal–Wallis with Bonferroni-adjusted Dunn post hoc comparisons; and logistic regression adjusted for age, sex, and marital status. Results: EBV seropositivity was higher in SCH (90.9%) than in HC (78.9%) (OR = 3.46, 95% CI: 1.68–7.12; p = 0.001) but not in BPD or MDD. HSV-1 seropositivity was elevated in BPD (83.5%) versus HC (67.0%) (OR = 2.29, 95% CI: 1.34–3.92; p = 0.003), with no differences in SCH or MDD. Inflammatory biomarkers were significantly increased in SCH and MDD compared to HC (p < 0.001), while BPD showed no differences. Conclusions: The findings delineate distinct immunovirological patterns across major psychiatric disorders. Schizophrenia was characterized by EBV seropositivity accompanied by systemic inflammatory activation, bipolar disorder by HSV-1 seropositivity in the absence of inflammatory changes, and major depressive disorder by inflammatory dysregulation independent of viral exposure. These disorder-specific profiles highlight heterogeneity in neuroimmune pathways and underscore the potential relevance of biomarker-based stratification for generating hypotheses regarding targeted antiviral or anti-inflammatory interventions in psychiatric populations. Full article

Infectious agents account for millions of deaths every year. The Herpes Simplex Viruses (HSVs) are large double-stranded DNA viruses that infect more than 90% of the human population and can establish life-long latency in human hosts. Currently, effective FDA approved anti-herpetic drugs include acyclovir and later-generation derivatives (valacyclovir and famciclovir), which inhibit viral DNA synthesis. In previous work, we demonstrated that the small molecule Ruvidar^® could inhibit numerous pathogenic human viruses when added to solutions of viruses both with and without light activation. In these experiments, we evaluated the ability of Ruvidar^® to restrict HSV-1 replication in Vero cells, both by itself and in combination with acyclovir and metformin in the absence of light activation to mimic deep tissue. Ruvidar^® successfully inhibited HSV-1 replication at significantly lower concentrations and more effectively than either acyclovir or metformin alone. We also discovered additive and synergistic anti-HSV-1 effects when combinational therapy was tested. Ruvidar^® also restricted HSV-1 replication in human U251 glioblastoma astrocytoma cells, remained highly effective against acyclovir-resistant HSV-1 mutants, and protected infected cells from virus-induced cytopathology. Full article

Fibrinogen (FIB), a key component of the coagulation cascade, is traditionally recognized for its role in hemostasis and tissue repair. However, due to its high plasma abundance and susceptibility to proteolytic cleavage during inflammation, it may also represent a previously unrecognized source of bioactive peptides. This study presents, for the first time, a comprehensive analysis of the antimicrobial, anti-inflammatory, and antiviral properties of six cationic antimicrobial peptides (AMPs) deriving from the C-terminal extremities of the three subunits of human fibrinogen (FIBα, FIBβ, and FIBγ), identified using a scoring function developed by our group. Antibacterial assays against Gram-positive and Gram-negative pathogens revealed different antimicrobial activity profile depending on their parent protein. Selected peptides displayed additive or synergistic effects when combined with conventional antibiotics or the thrombin-derived peptide (P)GKY20, highlighting their potential for combination therapies. Hemolytic assay confirmed the biocompatibility of fibrinogen-derived cryptic peptides with erythrocytes. Furthermore, the peptides significantly reduced LPS-induced nitric oxide release in murine macrophages Raw 264.7 cells, indicating anti-inflammatory activity. Notably, antiviral activity was observed against enveloped viruses (HCoV-229E and HSV-1) under various treatment conditions, while no activity was detected against the non-enveloped virus CVB3. Overall, these findings reveal human fibrinogen as a source of multifunctional cryptic peptides with broad-spectrum antimicrobial, antiviral, and immunomodulatory activities, supporting their potential as part of the innate immune system. Full article

Magnolia raw materials have long been used in Chinese folk medicine. The biologically active chemical compounds in Magnolia, mainly lignans, e.g., honokiol, exert health-enhancing effects in certain diseases, including skin conditions. Since the scientific literature does not provide a comparative analysis of the therapeutic properties of honokiol on the skin in various biological models, an attempt was made to supplement the knowledge in this field. This review presents the antimicrobial, anti-inflammatory, and photoprotective properties of honokiol used in dermatological problems and its anticancer activity in melanoma and non-melanoma skin cancers. Honokiol reduces the expression of HSV-1 genes, inhibits DNA replication, lowers the level of proteins, regulates the colonisation of viral glycoproteins with high membrane selectivity, and inhibits the endocytosis process. It has antibacterial activity, as it destroys bacterial cell walls and membranes. It disrupts vacuolar functioning and intracellular calcium homeostasis in dermatophyte cells and inhibits fungal growth by delaying germination, altering membrane permeability, and reducing hyphal growth. It reduces inflammatory cytokines and stimulates anti-inflammatory cytokine IL-10. Honokiol prevents UV-B induced skin cancer through targeting cell cycle regulators, inflammatory mediators, and cell survival signals. It induces apoptosis via extrinsic and intrinsic pathways, activating proapoptotic proteins. It acts as an inhibitor of the oncogenic protein KRT18 in melanoma and prevents the progression of highly metastatic melanoma. Future research should explore the signalling pathways and molecular mechanisms of honokiol action and its synergistic effects at the cellular level and help to develop methods for delivering honokiol to the organism by nanocarriers to improve selective therapies in some diseases. Full article

Authorized SARS-CoV-2 vaccines elicit both antibody and T-cell responses; however, benchmark correlates and update decisions have largely emphasized neutralizing antibodies. Motivated by the complementary role of cellular immunity, we designed a prototype polyepitope DNA vaccine encoding conserved human and mouse T-cell epitopes from non-structural proteins of the original strain SARS-CoV-2 lineage. Epitope selection was guided by in silico predictions for common HLA class I alleles in the Brazilian population and the mouse H-2Kb haplotype. To enhance immunogenicity, the polyepitope sequences were fused to glycoprotein D (gD) from Herpes Simplex Virus 1 (HSV-1), an immune activator of dendritic cells (DCs), leading to enhanced activation of antigen-specific T-cell responses. Mice were immunized with two doses of the electroporated DNA vaccine encoding the gD-fused polyepitope, which induced robust interferon-gamma– and tumor necrosis factor-alpha–producing T cell responses compared to control mice. In addition, K18-hACE2 transgenic mice showed protection against intranasal challenge with the original SARS-CoV-2 strain, with reduced clinical symptoms, less weight loss, and decreased viral burden in both lung and brain tissues. The results experimentally confirm the protective role of T cells in vaccine-induced protection against SARS-CoV-2 and open perspectives for the development of universal anti-coronavirus vaccines. Full article

Oncolytic herpes simplex virus (oHSV) is a promising cancer immunotherapy that induces tumor cell lysis and stimulates anti-tumor immunity. Our previous single-cell RNA sequencing analysis of oHSV-treated medulloblastoma tumors revealed expansion and activation of tumor-infiltrating dendritic cells (DCs), and direct oHSV infection of DCs within the brain. While the therapeutic effects of oHSVs have been primarily attributed to tumor cell infection, we hypothesize that direct infection of DCs also contributes to therapeutic efficacy by promoting DC maturation and immune activation. Although the oHSV infection in DCs was abortive, it led to increased expression of major histocompatibility complex (MHC) class I/II and co-stimulatory molecules. oHSV-infected DCs activated naïve CD4⁺ and CD8⁺ T cells, inducing expression of CD69 and CD25. These primed T cells exhibited enhanced cytotoxicity against CT-2A glioma cells. Adoptive transfer of oHSV-infected DCs via subcutaneous injection near inguinal lymph nodes delayed tumor growth in a syngeneic CT-2A glioma model, independent of tumor viral replication and lysis. Mechanistically, our in vitro studies demonstrate that oHSV can directly infect and functionally activate DCs, enabling them to prime effective anti-tumor T cell responses. This study highlights the anti-tumor potential of leveraging oHSV-infected DCs to augment viroimmunotherapy as a cancer therapeutic. Full article

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