Search Results (262)

Magnetic Particle Imaging (MPI) detects superparamagnetic nanoparticles, enabling bimodal contrast with MRI. Resovist^®/Ferucarbotran, still used in research, has clinical safety compatibility but suboptimal MPI performance due to many small 5 nm SPIO cores. Magnetic fractionation can enrich larger cores, improving MPI signal and supporting cellular imaging applications. To enable bimodal MRI/MPI and assess in vivo extracellular vesicle (EV) labelling, we characterized the imaging sensitivity and cell-labelling performance of VivoTrax, a commercial formulation similar to Resovist^®, and VivoTrax Plus, obtained by magnetic fractionation. VivoTrax Plus showed higher MRI transverse relaxivity and MPI sensitivity than VivoTrax, and both formulations displayed low toxicity toward adipose-derived stem cells (ASCs). VivoTrax Plus allowed MRI detection of small cell numbers, around 100 cells, in agarose phantoms with greater sensitivity than VivoTrax. However, EVs of 30–150 nm isolated from ASCs labelled with VivoTrax Plus did not retain SPIONs, whereas EVs from VivoTrax-labelled ASCs did. Preliminary in vivo experiments in SOD-G93A mice showed MRI-detectable signal voids in the brain after intranasal EV administration, suggesting EV migration to lesioned areas. Overall, magnetic fractionation improves SPION imaging sensitivity but may alter relevant biological properties. Full article

Background/Objectives: Ketamine has attracted interest in psychiatry due to its rapid antidepressant effects, particularly in patients with inadequate response to conventional treatments. This scoping review maps ketamine’s neuropharmacology, mechanisms of action, clinical applications, safety, and use in psychiatric disorders. Methods: This scoping review was conducted according to the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews. PubMed, Scopus, Web of Science, and Google Scholar were searched for English-language publications addressing ketamine pharmacology, clinical applications, and psychoactive effects. Included sources comprised randomized controlled trials, observational studies, systematic reviews, and relevant mechanistic studies, while non-English publications, editorials, commentaries, and studies without sufficient methodological information were excluded. Data were extracted using a structured data-charting form and synthesized narratively and thematically. Results: A total of 69 studies were included in the final synthesis. Ketamine demonstrated early improvements in depressive symptoms, especially in treatment-resistant depression (TRD), although the durability of benefits varied across studies. Intravenous racemic ketamine was the most extensively investigated administration route, while intranasal esketamine represents the primary approved formulation for TRD. Mechanistically, the drug acts through N-methyl-D-aspartate receptor antagonism and downstream modulation of glutamatergic signaling, synaptic plasticity and neural connectivity. Comparisons with conventional antidepressants and neuromodulatory interventions highlighted ketamine’s faster onset of action, although variability remained regarding long-term effects and treatment strategies. Conclusions: Ketamine represents an important rapid-acting treatment for TRD and severe depressive episodes associated with suicidal ideation. However, information regarding long-term efficacy and safety remains limited due to study heterogeneity, short follow-up periods, and variability in dosing protocols. Further research is needed to address gaps related to long-term outcomes, maintenance strategies, and optimal dosing approaches. Full article

Disorders of the central nervous system (CNS) are intricate and often resistant conditions that create a significant global impact, affecting millions of individuals each year. The blood–brain barrier (BBB) acts as a protective mechanism for the brain against external substances, but it also prevents most therapeutic agents from entering the CNS, leading to inadequate drug absorption and reduced effectiveness after diagnosis. Nasal drug delivery has emerged as a viable approach to bypass the BBB, facilitating direct access to the brain through the olfactory and trigeminal nerve routes. Although considerable research focuses on innovative nasal formulations with proven clinical promise, a critical gap persists: a systematic framework that bridges laboratory breakthroughs with clinical implementation. This review addresses this unmet need by integrating recent basic research advances with practical clinical requirements. We summarize nasal transport pathways, targeted design strategies, formulation optimization, and device engineering. Crucially, we propose a structured clinical evaluation framework built upon five essential pillars: targeting precision, pharmacokinetic performance, multi-organ safety profiling, device–drug clinical compatibility, and anatomical translation from animal models to humans. By mapping current research capabilities against clinical readiness criteria, this framework identifies translational bottlenecks and provides actionable guidance to accelerate the bench-to-bedside transition of intranasal drug delivery systems for CNS disorders. Full article

Nose-to-brain (N2B) delivery is a practical, non-invasive strategy for CNS targeting that can increase brain exposure while limiting systemic exposure. This review integrates three milestones in N2B delivery, formulations, devices, and quantitative evaluation strategies, to define design rules for effective olfactory/trigeminal deposition and enhance translational relevance. Formulations emphasize mucoadhesive systems, nanoparticle carriers (polymeric, lipid-based, and hybrid), nano-emulsions, and stimuli-responsive “smart” gels that prolong nasal residence. Regarding device advancements, the review covers conventional nasal sprays optimized for plume geometry and droplet size. Furthermore, it examines breath-actuated metered sprays, which promote soft palate closure to route aerosols to superior regions, and vibrating mesh nebulizers capable of low-velocity mists for improved upper cavity deposition. Quantitative evaluation is discussed, including 3D-printed, anatomy-accurate nasal casts, high-speed spray diagnostics, and computational fluid dynamics (CFD). This review further links formulation and device parameters to regional deposition. Available clinical and animal data illustrate the feasibility of these approaches, safety considerations, and user-technique dependencies, while highlighting the need for standardized, anatomy-aware testing protocols. Together, these developments suggest that co-designed formulation device platforms, validated by cast/CFD metrics and supported by clinical imaging or pharmacokinetic data, can support N2B product development toward consistent, patient-relevant outcomes. Full article

Background: Alzheimer’s disease (AD) is the seventh leading cause of death worldwide, posing a substantial global health burden. Although galantamine (GNT) is a first-line clinical drug for AD treatment, its therapeutic efficacy is constrained by inefficient brain delivery across the blood–brain barrier (BBB). Nose-to-brain delivery represents a promising route to bypass the BBB. However, its efficiency remains limited by insufficient drug deposition in the anatomically restricted olfactory region. In this study, we developed a galantamine nasal spray (GNT-NS) with enhanced olfactory region deposition and evaluated its feasibility for nose-to-brain delivery in AD treatment. Methods: We optimized the formulation by systematically investigating the cascade relationship among formulation physicochemical properties, spray performance, and olfactory region deposition. Nasal deposition distribution was quantitatively evaluated using a physiologically realistic 3D-printed human nasal cavity model reconstructed from clinical magnetic resonance imaging (MRI) data. Further, the in vivo biodistribution and therapeutic efficacy of GNT-NS were evaluated in AD rats. Results: The optimized formulation P₃ achieved an olfactory region fraction of 23.85%, markedly exceeding that of the unoptimized formulation P₀. Subsequent in vivo biodistribution studies showed that P₃ produced higher brain drug exposure than both intranasally administered P₀ and the commercial oral formulation. Further pharmacodynamic studies demonstrated that GNT-NS significantly improved cognitive and behavioral deficits in AD rats, exhibiting superior therapeutic efficacy over commercially available oral galantamine tablets. Conclusions: Collectively, this study proposes a cascade regulation strategy linking formulation physicochemical properties, spray performance, and olfactory region deposition and demonstrates that optimizing nasal spray properties can enhance olfactory deposition, increase brain exposure and improve therapeutic efficacy. These findings provide a useful reference for the design of nose-to-brain delivery formulations for AD and other central nervous system diseases. Full article

Intranasal corticosteroids (INCS) remain the cornerstone of pharmacologic treatment for allergic rhinitis (AR) because of their well-established anti-inflammatory efficacy and generally favorable benefit–risk profile. Nevertheless, concerns regarding local and systemic corticosteroid-related adverse events (AEs) continue to influence patient adherence, prescribing practices, and long-term treatment acceptance. In routine clinical practice, safety perception and corticosteroid-related concerns frequently influence adherence and formulation selection to a greater extent than differences in clinical efficacy, particularly in pediatric populations and in patients requiring prolonged continuous therapy. Differences in pharmacokinetic and pharmacodynamic properties, including systemic bioavailability, glucocorticoid receptor affinity, lipophilicity, protein binding, and extent of first-pass metabolism, are considered important safety profile determinants of currently available INCS formulations. Available evidence indicates that local AEs, particularly epistaxis, nasal irritation, dryness, and sensory discomfort, represent the most frequently reported treatment-related AEs across INCS formulations, although these events are generally mild, self-limiting, and infrequently treatment-limiting. Clinically significant structural nasal complications, including septal perforation or progressive mucosal injury, appear uncommon in currently available studies. Systemic AEs, including hypothalamic–pituitary–adrenal (HPA) axis suppression, ocular toxicity, growth impairment, or clinically meaningful effects on bone metabolism, have not been consistently demonstrated with currently used low-systemic-exposure formulations administered at recommended therapeutic doses. Although systemic glucocorticoid exposure has been associated with alterations in lipid metabolism, adipose tissue function, and metabolic homeostasis, currently available intranasal corticosteroids demonstrate minimal systemic exposure, making clinically relevant metabolic effects unlikely under recommended therapeutic conditions. Formulations such as mometasone furoate, fluticasone propionate, fluticasone furoate, and ciclesonide exhibit pharmacokinetic characteristics associated with minimal systemic exposure because of extensive first-pass metabolism and low oral bioavailability. Although substantial pharmacokinetic differences exist between currently available INCS formulations, direct comparative evidence demonstrating clinically meaningful superiority in systemic safety outcomes remains limited. Current evidence suggests that formulation-dependent differences are clinically more relevant with respect to local tolerability, sensory characteristics, patient preference, and long-term adherence than major systemic safety outcomes. Pediatric evidence is generally reassuring, although historical concerns regarding growth suppression associated with earlier corticosteroid formulations continue to influence clinical practice. Currently available evidence supports the use of modern INCS as effective and generally well-tolerated therapeutic options across adult and pediatric populations. Full article

Background: Effective strategies for delivering neuroprotective agents to the brain remain a major challenge due to the poor solubility, rapid metabolism, and low bioavailability of promising molecules, such as 7,8-dihydroxyflavone (7,8-DHF). This small-molecule TrkB receptor agonist exhibits significant antioxidant, neuroprotective properties, and additional effects on metabolic regulation, but its therapeutic potential is limited by unfavorable pharmacokinetic characteristics. Nanotechnology-based delivery systems are increasingly explored to improve drug stability, enhance bioavailability, and facilitate direct nose-to-brain transport following intranasal administration. In this study, lipid nanoparticles encapsulating 7,8-DHF were developed using a fish-oil-based lipid core enriched with ω-3 polyunsaturated fatty acids (DHA and EPA) and naturally derived excipients, including soybean lecithin and ε-polylysine. Methods: The formulation was optimized using a Design of Experiments (DoE) approach based on a 2³ full factorial design, evaluating drug concentration, lecithin concentration, and surfactant type (Pluronic^® F127 or Tween^® 80). The main formulation responses considered were particle size, polydispersity index (PDI), zeta potential, and encapsulation efficiency. Results: The optimized nanoparticles exhibited nanometric dimensions (<250 nm); spherical morphology, confirmed by TEM; low polydispersity (PDI < 0.3); and adequate encapsulation efficiency. Stability studies in simulated biological fluids indicated good physicochemical stability for up to 48 h, while interaction studies with mucin suggested a good interaction within the mucus environment. ROS scavenging capacity was confirmed through the DPPH chemical assay, and in vitro experiments on olfactory ensheathing cells, selected as a biologically relevant model for their anatomical localization along the olfactory pathway, showed reduced cytotoxicity of the encapsulated drug compared with the free form. Conclusions: Collectively, these results support the potential application of the developed nanoformulation in the intranasal delivery of 7,8-DHF. Full article

Extensive efforts have been undertaken by numerous researchers to control respiratory viruses across the domains of diagnosis, prevention, and treatment. In this study, we developed a niclosamide–polysaccharide nasal spray (NPNS) formulation based on xanthan gum (XG), a naturally derived polysaccharide, and niclosamide, a conventional anthelmintic agent. We then evaluated its therapeutic efficacy following intranasal administration under influenza virus-infected conditions. NPNS was assessed for cytotoxicity under Good Laboratory Practice (GLP) conditions in accordance with ISO 10993-5, and no cytotoxic effects were observed. In influenza virus-infected human nasal epithelial cells (HNEc), NPNS treatment resulted in at least 92.5% suppression of viral gene expression. Furthermore, NPNS demonstrated significantly greater antiviral activity compared to Placebo 1 and Placebo 2, which were formulated by excluding niclosamide and XG, respectively. Owing to the physicochemical properties conferred by XG, NPNS exhibited prolonged retention on the nasal mucosa in a mouse model. Consistently, NPNS showed potent antiviral efficacy in influenza-infected mice. In addition, NPNS treatment was associated with the downregulation of S-phase kinase-associated protein 2 (SKP2), a host factor known to facilitate intracellular viral replication. Collectively, these findings suggest that NPNS may serve as a first-line protective barrier during the early stage of influenza infection by simultaneously blocking viral entry and suppressing viral replication through its dual physicochemical and molecular mechanisms. Full article

Objectives: this study aimed to develop and optimize an intranasal delivery system for Eplerenone (EPL) by incorporating Eplerenone-loaded liposomes (Elip) into an in situ gel system (Elip-GG). The goal was to prolong the residence time of the drug in the nasal cavity and ensure sustained release. Methods: Elip and unloaded liposomes were prepared using the thin-film hydration method. Key formulation variables such as encapsulation efficiency (EE%), mean particle size (MPS), polydispersity index (PDI), and zeta potential (ZP) were optimized. The Elip was then incorporated into a gellan gum (GG) in situ gel to form Elip-GG. The Elip-GG formulation was evaluated based on parameters such as pH, viscosity, rheological behavior, mechanical properties, and in vitro release. Results: the optimal Elip formulation exhibited an EE of 86.3%, a mean particle size of 86.56 nm, a PDI of 0.29, and a ZP of −29.86 mV. The cumulative drug release from the Elip-GG formulation exceeded 93% after 2.5 h. The Elip-GG formulation significantly increased the sustained release of Eplerenone when administered intranasally, offering a promising alternative to oral and parenteral delivery methods for hydrophilic antihypertensive drugs. Full article

Background: Avian influenza is a critical zoonotic infection threatening both the poultry industry and global public health. While traditional intramuscular vaccines elicit systemic immunity, they often fail to provide robust local protection at mucosal surfaces. There is thus significant interest in the development of mucosal avian influenza vaccines administered via the intranasal route. However, in humans, this approach is significantly hampered by the availability of safe and effective adjuvants. Methods: This study investigated the immunogenicity of a modified recombinant influenza A/H5 hemagglutinin (rHA/H5-modif) formulated with Novochizol, a novel chitosan-derived delivery system, administered intranasally to laboratory animals. Results: Our results demonstrate that mucosal immunization with the rHA/H5-modif/Novochizol complex induces potent humoral (IgG and IgA) and cell-mediated immune responses. Crucially, the formulation provided 100% survival in mice following a lethal challenge with highly pathogenic avian influenza A/H5. Conclusions: These findings position the rHA/H5-modif/Novochizol complex as a promising candidate for next-generation mucosal vaccines, in particular against highly pathogenic avian influenza A/H5 subtype. Full article

Vaccination represents the cornerstone of Newcastle disease control. Nanotechnology offers a promising approach to improve the effectiveness of DNA vaccines, supporting their use as an alternative to conventional platforms. Herein, the Avian Orthoavulavirus 1 (AOAV-1) fusion (F) gene was cloned into a DNA expression plasmid (pDNA). After validating the constructed pDNA-F and confirming robust intracellular protein expression in vitro, three polymeric nanoparticles (NPs)-based formulations were generated using Chitosan (Cs), poly(lactic-co-glycolic) (PLGA), and poly(amidoamine) (PAMAM)-Dendrimers. Physicochemical characterization, stability assessment, and in vitro release analysis confirmed nanoparticle formation and effective DNA incorporation. In vivo experiments were conducted to comparatively evaluate the immunogenicity, particularly the immune priming capacity, and protective efficacy of nanoparticle-based formulations and naked pDNA-F, all tested in parallel at standardized pDNA doses via intranasal (IN) and intramuscular routes. PAMAM-Dendrimers-pDNA-F IM group demonstrated superior efficacy, with 100% survival, the highest post-challenge anamnestic antibody titers, and a pronounced reduction in viral RNA shedding. PLGA-NPs-pDNA-F IN group demonstrated enhanced efficacy, with 90% survival. Naked pDNA-F surpassed the Cs-NPs-pDNA-F in both immune priming and clinical protection, with Cs-NPs-pDNA-F exhibiting the lowest overall performance. These findings highlight that DNA vaccine performance depends on both carrier type and administration route, with PAMAM dendrimers and PLGA enhancing efficacy, whereas chitosan demonstrated reduced efficacy under the tested conditions. Full article

Influenza A virus (IAV) remains a major global health threat despite available vaccines and antiviral agents, while current therapies are limited by drug resistance and safety concerns. Curcuminoids exhibit antiviral and anti-inflammatory activities but are constrained by poor water solubility and low bioavailability. To address these limitations, we investigated the antiviral and immunomodulatory properties of a water-solubilized curcuminoid nanoparticle formulation (C–S/M) in both in vitro and in vivo models of IAV infection. To evaluate the potential antiviral and anti-inflammatory effects of C–S/M, we performed a cytopathic effect (CPE) reduction assay in triplicate at 0.001 MOI and quantitative real-time PCR (qRT-PCR) targeting viral NS1 transcripts in MDCK cells. C–S/M suppressed viral NS1 vRNA levels in MDCK cells at lower curcuminoid-equivalent concentrations than native curcuminoids and attenuated IAV-induced TNF-α, IL-6, and IL-8 production. Furthermore, in vivo antiviral efficacy was evaluated in female C57BL/6 mice intranasally infected with IAV and treated orally with C–S/M. Survival, lung viral loads, pulmonary cytokine levels, and splenic immune cell phenotypes were analyzed. In IAV-infected mice, oral administration of C–S/M modestly improved survival and significantly reduced lung viral burden and pulmonary proinflammatory cytokine levels. In addition, in vivo C–S/M treatment was associated with recovery of virus-suppressed T-cell immune responses, including increased Th1 and activated CD8⁺ T cells, reduced regulatory T-cell expansion, and restoration of multifunctional CD4⁺ and CD8⁺ T cells. These findings suggest that C–S/M exerts antiviral and immunomodulatory effects in experimental IAV infection and may serve as a potential adjunctive candidate for further investigation against influenza-associated inflammation. Full article

The absence of robust and effective treatments for Alzheimer’s disease remains a major challenge in modern medicine. As one of the leading causes of death, its increasing prevalence and complex chronic pathogenesis impose a substantial societal and healthcare burden, intensifying the need for effective therapeutic strategies. Current treatments remain limited, with minimal impact on cognitive decline in symptomatic patients. Curcumin, the bioactive ingredient in turmeric, has taken precedence over other natural products due to its potent antioxidative and anti-inflammatory properties. Numerous publications have extensively reported on the therapeutic effect of curcumin in animal models of Alzheimer’s disease. However, no curcumin formulation has demonstrated consistent clinical efficacy against Alzheimer’s or other neurodegenerative diseases to date. Over the years, many critics have argued that curcumin’s undesirable chemical properties, mainly low bioavailability and rapid metabolism, pose significant barriers to its therapeutic use to target the brain. Considerable funding and research effort on emerging technologies such as nanoparticles and intranasal delivery continue to drive curcumin preclinical and clinical trials, prompting reflection on the rationale for continued investment. This narrative review critically dissects this disconnect, arguing that many purported benefits remain insufficiently substantiated, and identifying important opportunities where future research may hold promise for an effective treatment. Full article

Most infectious pathogens enter the host through mucosal surfaces, yet conventional injectable vaccines primarily induce systemic immunity without eliciting robust secretory immunoglobulin A (SIgA) responses at mucosal sites. The COVID-19 pandemic highlighted this limitation, as intramuscular mRNA vaccines failed to establish durable mucosal immunity in the upper respiratory tract. This review covers recent progress in mucosal vaccine development. We first discuss the organization of the mucosal immune system, focusing on SIgA induction, tissue-resident memory T (${\mathrm{T}}_{\mathrm{RM}}$) cells, and resident memory B (${\mathrm{B}}_{\mathrm{RM}}$) cells. We then examine mucosal adjuvants, from cholera toxin and heat-labile enterotoxin derivatives to stimulator of interferon gene (STING) agonists and a strategy to enhance alum adjuvanticity through neutrophil elastase inhibition. Delivery routes including intranasal, oral, and sublingual administration are reviewed alongside viral vectors, nanoparticles, mRNA-lipid nanoparticles, virus-like particles, and engineered bacterial platforms. The roles of innate immune cells, T helper cell subsets, and the microbiota in shaping vaccine responses are discussed. Finally, we survey licensed mucosal vaccines and the COVID-19 mucosal vaccine pipeline, analyze persistent barriers to clinical translation including the absence of validated mucosal correlates of protection, and outline future directions for thermostable formulations and systems biology-driven vaccine design. Full article

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infects host cells through the interaction between the spike protein receptor-binding domain (RBD) and the human angiotensin-converting enzyme 2 (hACE2) receptor, which is expressed on epithelial cells in various tissues, including the respiratory tract. Therefore, mucosal immunity in the respiratory tract plays a key role in protection against viral infection. Previously, we demonstrated that intranasal administration of antigens (Ags) conjugated with the M cell-targeting peptide Co4B enhances both mucosal and systemic immune responses. That conjugation with human β-defensin 2 (HBD2) increases neutralizing antibody (Ab) responses. Methods: A recombinant antigen conjugate incorporating both Co4B and HBD2 was designed to enhance immunogenicity. Its immunogenicity was evaluated in mice following intranasal immunization. Antigen-specific antibody responses were measured in serum and bronchoalveolar lavage fluid. T-cell responses were evaluated in lungs and spleens. Protective efficacy was assessed using SARS-CoV-2-susceptible hACE2 knock-in mice. Results: Ag-specific Ab levels increased in both serum and bronchoalveolar lavage fluid of mice immunized intranasally with the conjugate. Especially, T-cell responses were significantly enhanced in the lungs and spleens of immunized hACE2 knock-in mice. In challenge experiments, intranasal administration of the conjugate reduced viral load. Moreover, Siglec F was identified as a potential receptor for Co4B, a previously uncharacterized M cell-targeting ligand. Conclusions: A recombinant viral Ag containing Co4B and HBD2 induces virus-specific humoral and cellular immune responses. Although further optimization of the vaccine formulation and administration strategy is needed, this conjugate shows potential as a platform for improving mucosal and systemic immunity. Full article