[The auxiliary diagnostic value of ECP and MPO expression in nasal secretions in different types of rhinitis].

Objective:To evaluate the expression of eosinophil cationic protein and myeloperoxidase in nasal secretions in different types of rhinitis, and to explore their values in the differential diagnosis of different types of rhinitis. Methods:Six hundred and eighty-four subjects were selected, including 62 subjects in the acute rhinitis group, 378 subjects in the allergic rhinitis group, 94 subjects in the vasomotor rhinitis group, 70 subjects in the eosinophilic non-allergic rhinitis group, and 80 subjects in the control group. Nasal secretion samples were collected from the five groups, and the percentages of inflammatory cells were counted by Rachel's staining, and the expression of ECP/MPO was detected by colloidal gold assay. The correlation between the clinical diagnosis, the inflammatory cells in the nasal secretions and the expression of ECP/MPO was analyzed. Results:Nasal cytological smears showed that compared with the control group, the percentage of eosinophils in the AR and NARES groups were significantly higher （P<0.05）, while the percentage of neutrophils was not different （P>0.05）; the percentage of neutrophils was significantly higher in the acute rhinitis group compared with the control group （P<0.05）, while the percentage of eosinophils was not statistically different （P>0.05）; in vasomotor rhinitis group, the eosinophils and neutrophils were not statistically different compared with the control group（P> 0.05）. The colloidal gold results showed that there were differences in the expression of ECP/MPO in different types of rhinitis, among which 49 cases （79.0%） in the acute rhinitis group expressed ECP+/MPO+; 267 cases （70.6%） in the AR group and 56 cases （75.7%） in the NARES group expressed ECP+/MPO-; 80 cases （85.1%） in the vasomotor rhinitis group and 69 cases （86.3%） in the control group expressed ECP-/MPO-. Conclusion:The differences in ECP and MPO expression between different types of rhinitis have certain reference value for the differential diagnosis of different types of rhinitis and the selection of treatment programs.

Retinoic Acid Treatment Mitigates PM2.5-Induced Type 2 Inflammation: Insights into Modulation of Innate Immune Responses.

Some studies have demonstrated the effects of particulate matter (PM) on chronic rhinosinusitis with nasal polyps (CRSwNP) development, as well as the therapeutic role of retinoic acid (RA) in nasal polypogenesis. However, the immunologic effect of PM in innate lymphoid cells (ILCs) and the exact mechanism of the therapeutic effect of RA remain unclear. Therefore, the present study investigated the effects of fine-dust-induced inflammation in CRSwNP and the mechanisms of the therapeutic effect of RA. PM2.5 exposure exacerbated pathological damage in the nasal mucosa of mice with nasal polyps (NP) via upregulation of type 2 inflammation. Additionally, PM2.5 exposure increased the expression of type 2 cytokines and epithelial-cell-derived cytokines (IL-33 and IL-25) significantly, as well as the ILC populations in human-NP-derived epithelial cells (HNECs). Moreover, RA supplementation significantly increased the expression of ILCreg in Lin-CD45+CD127+ cells, which in turn increased the levels of the anti-inflammatory cytokine IL-10. The findings suggest that PM2.5 exposures could aggravate the CRSwNP type 2 inflammation, and RA treatment may ameliorate fine-dust-induced inflammation by modulating the innate immune response.

Localized Expression of Olfactory Receptor Genes in the Olfactory Organ of Common Minke Whales.

Baleen whales (Mysticeti) possess the necessary anatomical structures and genetic elements for olfaction. Nevertheless, the olfactory receptor gene (OR) repertoire has undergone substantial degeneration in the cetacean lineage following the divergence of the Artiodactyla and Cetacea. The functionality of highly degenerated mysticete ORs within their olfactory epithelium remains unknown. In this study, we extracted total RNA from the nasal mucosae of common minke whales (Balaenoptera acutorostrata) to investigate ORs' localized expression. All three sections of the mucosae examined in the nasal chamber displayed comparable histological structure. However, the posterior portion of the frontoturbinal region exhibited notably high OR expression. Neither the olfactory bulb nor the external skin exhibited the expression of these genes. Although this species possesses four intact non-class-2 ORs, all the ORs expressed in the nasal mucosae belong to class-2, implying the loss of aversion to specific odorants. These anatomical and genomic analyses suggest that ORs are still responsible for olfaction within the nasal region of baleen whales, enabling them to detect desirable scents such as prey and potential mating partners.

Intranasal administration of ceramide liposome suppresses allergic rhinitis by targeting CD300f in murine models.

Allergic rhinitis (AR) is caused by type I hypersensitivity reaction in the nasal tissues. The interaction between CD300f and its ligand ceramide suppresses immunoglobulin E (IgE)-mediated mast cell activation. However, whether CD300f inhibits the development of allergic rhinitis (AR) remains elusive. We aimed to investigate the roles of CD300f in the development of AR and the effectiveness of intranasal administration of ceramide liposomes on AR in murine models. We used ragweed pollen-induced AR models in mice. Notably, CD300f deficiency did not significantly influence the ragweed-specific IgE production, but increased the frequency of mast cell-dependent sneezing as well as the numbers of degranulated mast cells and eosinophils in the nasal tissues in our models. Similar results were also obtained for MCPT5-exprssing mast cell-specific loss of CD300f. Importantly, intranasal administration of ceramide liposomes reduced the frequency of sneezing as well as the numbers of degranulated mast cells and eosinophils in the nasal tissues in AR models. Thus, CD300f-ceramide interaction, predominantly in mast cells, alleviates the symptoms and progression of AR. Therefore, intranasal administration of ceramide liposomes may be a promising therapeutic approach against AR by targeting CD300f.

Advantages of the co2 laser use in the rare condition of nasal mucosa squamous cell carcinoma surgery in dogs-a clinical prospective study.

Nasal mucosa tumors are an uncommon process and very dificult to work on with surgery. Radiotherapy associated or not with chemotherapy is the standard method to treat the disease. However, its access it is in the majority of the case not possible, making the surgery the best choice to try to achieve the patient's control. The anatomy of the region makes the complete surgical resection very difficult to achieve using the common and conventional blade scalpel surgery. The study features the advantages of using a CO2 laser to perform nasal mucosa carcinoma surgery in 6 dogs (N = 6). For the work we used an Aesculigth CO2 surgical laser model -Vetscalpel®, with the settings of 12Watts in a Superpulse mode, and a 0.25-0.4 mm focus to dissect the nasal mucosa, and a 1.5 mm focus for vaporization of the area. All the masses were histopathologically characterized as squamous cells carcinoma. The CO2 surgical laser allow us to work in a bloodless region promoting a more accurate dissection of the nasal mucosa sparing therefore the underlying and adjacent tissues and being less invasive. Also, it was possible to do the vaporization of the entire surgical area interviened. None of the patients presented relapse of clinical signs. Only 2 individuals were alive at the end of the study, presenting a survival rate of 420 and 514 days, which is in the same line of literature results of the treatment with radiotherapy combined with chemotherapy wich shows a median of 474-580 days. The study demonstrates successful outcomes with CO2 laser surgery in treating nasal mucosa SCC in dogs, with patients experiencing improved survival rates compared to traditional treatment methods. This highlights the efficacy and potential of CO2 laser surgery as a valuable tool in managing aggressive nasal tumors in veterinary oncology.

Smoking-associated gene expression alterations in nasal epithelium reveal immune impairment linked to lung cancer risk.

BACKGROUND: Lung cancer is the leading cause of cancer-related death in the world. In contrast to many other cancers, a direct connection to modifiable lifestyle risk in the form of tobacco smoke has long been established. More than 50% of all smoking-related lung cancers occur in former smokers, 40% of which occur more than 15 years after smoking cessation. Despite extensive research, the molecular processes for persistent lung cancer risk remain unclear. We thus set out to examine whether risk stratification in the clinic and in the general population can be improved upon by the addition of genetic data and to explore the mechanisms of the persisting risk in former smokers. METHODS: We analysed transcriptomic data from accessible airway tissues of 487 subjects, including healthy volunteers and clinic patients of different smoking statuses. We developed a computational model to assess smoking-associated gene expression changes and their reversibility after smoking is stopped, comparing healthy subjects to clinic patients with and without lung cancer. RESULTS: We find persistent smoking-associated immune alterations to be a hallmark of the clinic patients. Integrating previous GWAS data using a transcriptional network approach, we demonstrate that the same immune- and interferon-related pathways are strongly enriched for genes linked to known genetic risk factors, demonstrating a causal relationship between immune alteration and lung cancer risk. Finally, we used accessible airway transcriptomic data to derive a non-invasive lung cancer risk classifier. CONCLUSIONS: Our results provide initial evidence for germline-mediated personalized smoke injury response and risk in the general population, with potential implications for managing long-term lung cancer incidence and mortality.

[Acute and chronic rhinosinusitis age characteristics]. / Vozrastnye osobennosti techeniya ostrogo i khronicheskogo rinosinusita.

Children's and adults' rhinosinusitis are two diseases that have both similarities and differences in anatomy, epidemiology, causes, pathogenesis, diagnosis and treatment. At the same rhinosinusitis is one of the most common in otorhinolaryngology's practice, both in children and adults. The of adults paranasal sinuses (PNS) anatomy differs from children's PNS anatomy. Although ostiomeatal complex occlusion is recognized as a major cause of poor ventilation and drainage of the adult paranasal sinuses, it does not have a strong effect on pediatric rhinosinusitis, but adenoids play a key role. Adenoids are bacteria and biofilms reservoirs that cause chronic refractory rhinosinusitis regardless of pharyngeal tonsil size. The prevalence of chronic rhinosinusitis (CRS) is lower in children than in adults. Diagnosis of children's rhinosinusitis is more difficult because nasal cavity endoscopic examination is performed rarely due to the occasional need of general anesthesia during the procedure. Moreover, it's necessary to take into account prevailing etiological role of viruses in ARS at children's age and chronic adenoiditis often accompanies pediatric CRS, which requires attention prescribing medical therapy as the basis of rhinosinusitis treatment. The DysheLORz based on Pelargonium sidoides roots is highly effective and safe for children's and adults ARS and CRS treatment, both as monotherapy and in combination with topical steroids and antibiotics. This herbal medicine immunomodulatory effect is mediated mainly by stimulating the production of TNF-α, IL-1, IL-12 and IFN-γ. It activates macrophages and improves their phagocytic activity. IL-12, together with TNF-α, enhances NK and cytotoxic CD8+ lymphocytes' activity against infected cells. IL-12 effect on Th1 lymphocytes maturation provides a link between innate and adaptive immunity. This is also increasing MCP-1, IP-10 and MIP-1ß chemokines synthesis and decreasing MIP-1α, ENA-78, GROα and IL-8 production in PNS and nasal mucosa. This leads to decrease of neutrophils chemotaxis to the inflammation site, and decline of serine proteases concentration (neutrophils main enzymes), that increases mucous membrane epithelial barrier permeability, reducing bacterial infections risk. Additionally, Pelargonium sidoides increases epithelial cells beating cilia frequency and inhibits hemagglutinin and neuraminidase present on influenza virus surface. The drug increases antimicrobial peptides production as defensins, human neutrophil peptides (HNP) and bactericidal permeability-increasing protein (BPI), which is also important for rapid inflammation regression in rhinosinusitis. It causes bacterial adhesion to epithelial cells inhibition, phagocytosis stimulation, nitric oxide (NO) release and oxidative burst. The medicine had a direct effect on Streptococcus pneumoniae, Staphylococcus aureus, Neisseria, Moraxella catarrhalis and Haemophilus influenza. Based on these data, it is possible to explain the high effectiveness and safety of the drugs based on Pelargonium sidoides in ENT organs inflammation treatment, for both adults and children over 1 year old.

SerpinB3/B4 Abates Epithelial Cell-Derived CXCL8/IL-8 Expression in Chronic Rhinosinusitis with Nasal Polyps.

Background: Serine proteinase inhibitors, clade B, member 3 (SerpinB3) and B4 are highly similar in amino acid sequences and associated with inflammation regulation. We investigated SerpinB3 and B4 expression and their roles in chronic rhinosinusitis with nasal polyps (CRSwNP). Methods: The expression of SerpinB3 and B4 in nasal mucosa tissues, brush cells, and secretions from CRSwNP patients was measured, and their regulation by inflammatory cytokines were investigated. Their functions were also analyzed using air-liquid interface (ALI)-cultured primary human nasal epithelial cells (HNECs) and transcriptomic analysis. Results: Both SerpinB3 and B4 expression was higher in nasal mucosa, brush cells, and secretions from eosinophilic (E) CRSwNP and nonECRSwNP patients than in healthy controls. Immunofluorescence staining indicated that SerpinB3 and B4 were primarily expressed in epithelial cells and their expression was higher in CRSwNP patients. SerpinB3 and B4 expression was upregulated by interleukin-4 (IL-4), IL-5, IL-6, and IL-17a. Transcriptomic analysis identified differentially expressed genes (DEGs) in response to recombinant SerpinB3 and B4 stimulation. Both the DEGs of SerpinB3 and B4 were associated with disease genes of nasal polyps and inflammation in DisGeNET database. Pathway enrichment indicated that downregulated DEGs of SerpinB3 and B4 were both enriched in cytokine-cytokine receptor interactions, with CXCL8 as the hub gene in the protein-protein interaction networks. Furthermore, CXCL8/IL-8 expression was downregulated by recombinant SerpinB3 and B4 protein in ALI-cultured HNECs, and upregulated when knockdown of SerpinB3/B4. Conclusion: SerpinB3/B4 expression is upregulated in nasal mucosa of CRSwNP patients. SerpinB3/B4 may play an anti-inflammatory role in CRSwNP by inhibiting the expression of epithelial cell-derived CXCL8/IL-8.

Role of TRPV1 and TRPA1 in TSLP production in nasal epithelial cells.

BACKGROUND: TRP protein is sensitive to external temperature changes, but its pathogenic mechanism in the upper airway mucosa is still unclear. OBJECTIVE: To investigate the mechanism of TRPV1and TRPA1 in regulating the secretion of inflammatory factors in nasal epithelial cells. METHODS: The expression of TRPV1 and TRPA1 in nasal mucosal epithelial cells was investigated using immunofluorescence assays. Epithelial cells were stimulated with TRPV1 and TRPA1 agonists and antagonists, and changes in Ca2+ release and inflammatory factor secretion in epithelial cells were detected. TSLP secretion stimulated with the calcium chelating agent EGTA was evaluated. The transcription factor NFAT was observed by immunofluorescence staining. RESULTS: TRPV1 and TRPA1 expression was detected in nasal epithelial cells, and Ca2+ influx was increased after stimulation with agonists. After the activation of TRPV1 and TRPA1, the gene expression of TSLP, IL-25, and IL-33 and the protein expression levels of TSLP and IL-33 were increased, and only TSLP could be inhibited by antagonists and siRNAs. After administration of EGTA, the secretion of TSLP was inhibited significantly, and the expression of the transcription factor NFAT in the nucleus was observed after activation of the TRPV1 and TRPA1 proteins in epithelial cells. CONCLUSION: Activation of TRPV1 and TRPA1 on nasal epithelial cells stimulates the generation of TSLP through the Ca2+/NFAT pathway. It also induces upregulation of IL-25 and IL-33 gene expression levels and increased levels of IL-33 protein, leading to the development of airway inflammation.

Clozapine-laden carbon dots delivered to the brain via an intranasal pathway: Synthesis, characterization, ex vivo, and in vivo studies.

Clozapine, which is widely used to treat schizophrenia, shows low bioavailability due to poor solubility and high first-pass metabolism. The study aimed to design clozapine-loaded carbon dots (CDs) to enhance availability of the clozapine to the brain via intranasal pathway. The CDs were synthesized by pyrolysis of citric acid and urea at 200 °C by hydrothermal technique and characterized by photoluminescence, transmission electron microscopy (TEM), X-ray Photoelectron Spectrometer (XPS), and Fourier transform infrared spectrum (FTIR). The optimized clozapine-loaded CDs (CLZ-CDs-1:3-200) showed a quasi-spherical shape (9-12 nm) with stable blue fluorescence. The CDs showed high drug solubilization capacity (1.5 mg drug in 1 mg/ml CDs) with strong electrostatic interaction with clozapine (drug loading efficiency = 94.74%). The ex vivo release study performed using nasal goat mucosa showed sustained release of clozapine (43.89%) from CLZ-CDs-1:3-200 for 30 h. The ciliotoxicity study (histopathology) confirmed no toxicity to the nasal mucosal tissues using CDs. In the rat model (in vivo pharmacokinetic study), when CDs were administrated by the intranasal route, a significantly higher concentration of clozapine in the brain tissue (Cmax = 58.07 ± 5.36 µg/g and AUCt (µg/h*g) = 105.76 ± 12.31) was noted within a short time (tmax = 1 h) compared to clozapine suspension administered by intravenous route (Cmax = 20.99 ± 3.91 µg/g, AUC t (µg/h*g) = 56.89 ± 12.31, and tmax = 4 h). The high value of drug targeting efficiency (DTE, 486%) index and direct transport percentage (DTP, 58%) indicates the direct entry of clozapine-CDs in the brain via the olfactory route. In conclusion, designed CDs demonstrated a promising dosage form for targeted nose-to-brain delivery of clozapine for the effective treatment of schizophrenia.

Influence of pallet rich plasma, quercetin and their combination on activity of nitric oxide cycle enzymes in nasal mucosa of patients with atrophic rhinitis.

OBJECTIVE: Aim: To study the general activity of NO synthases (gNOS), the activity of inducible and constitutive isoforms of NO synthase, the activity of arginases, and the concentration of nitrites in the nasal mucosa under the conditions of local treatment of chronic atrophic rhinitis (AR) with quercetin and platelet-rich plasma (PRP therapy).. PATIENTS AND METHODS: Materials and Methods: The study was conducted on 118 patients divided into two groups: control (n=20) and experimental (patients with AR, n=98). Experimental group was divided into 4 subgroups: standard treatment (n=29), PRP therapy (6 injections for 28 day course, n=19), Quercetin (40 mg 3 times a day for 28 days, n=26) and PRP+Quercetin (n=24) groups. RESULTS: Results: Standard therapy of SaR increases gNOS by 278.38% and arginase activity increases by 222.73%. PRP therapy increases gNOS by 211.43% and arginase by 540.91%. Quercetin elevates gNOS by 108.33% and arginase by 250%. PRP therapy and quercetin increases gNOS by 146.15% and arginase by 536.36%. CONCLUSION: Conclusions: The use of standard therapy of SaR and addition of PRP therapy, quercetin and their combination effectively restores the production of nitric oxide and the arginase activity in the nasal mucosa.

Intranasal Nose-to-Brain Drug Delivery via the Olfactory Region in Mice: Two In-Depth Protocols for Region-Specific Intranasal Application of Antibodies and for Expression Analysis of Fc Receptors via In Situ Hybridization in the Nasal Mucosa.

A region-specific catheter-based intranasal administration method was successfully developed, established, and validated as reported previously. By using this method, drugs can be applicated specifically to the olfactory region. Thereby, intranasally administered drugs could be delivered via neuronal connections to the central nervous system. Here, we present a detailed protocol with a step-by-step procedure for nose-to-brain delivery via the olfactory mucosa.Fc receptors such as the neonatal Fc receptor (FcRn) and potentially Fcγ receptor IIb (FcγRIIb) are involved in the uptake and transport of antibodies via the olfactory nasal mucosa. To better characterize their expression levels and their role in CNS drug delivery via the nose, an in situ hybridization (ISH) protocol was adapted for nasal mucosa samples and described in abundant details.

Association between maxillary sinus floor perforation by dental implants and mucosal thickening: A cone-beam computed tomography study.

OBJECTIVE: To investigate the association of perforation of the maxillary sinus floor by dental implants with mucosal thickening and to describe its characteristics in perforated cases. STUDY DESIGN: One-hundred and twenty-nine maxillary sinuses of 93 patients presenting 202 dental implants in the maxillary posterior region were retrospectively assessed in cone-beam computed tomography scans and classified according to maxillary sinus perforation, bone graft, mucosal thickening, and mucosal appearance. Logistic regression determined the chance of mucosal thickening in perforated maxillary sinuses. The chi-square test compared categorical variables between maxillary sinus perforated or not by implants and maxillary sinus with or without mucosal thickening. The significance level assumed was 5 % (α = 0.05). RESULTS: There was perforation of 60 maxillary sinuses floor (46.5 %) by 74 dental implants. The chance of mucosal thickening was higher when the implant tip was trespassing on the maxillary sinus floor (p < 0.001). There was a significant association between maxillary sinus mucosal thickening and perforation by a dental implant with the tip trespassing the maxillary sinus floor (p < 0.05). CONCLUSION: Maxillary sinus mucosal thickening is associated with sinus floor perforation by dental implants and does not depend on the number of implants perforating it. CLINICAL RELEVANCE: There is an association between dental implants' perforation of the maxillary sinus floor and the thickening of the maxillary sinus. In those cases, the appearance of the mucosa thickening may be irregular, local, or total opacification of the sinus cavity.

miR-224-5p Attenuates Allergic Responses in Mice with Allergic Rhinitis by Modulating the Th1/Th2 Response.

Background: Allergic rhinitis (AR) is a common chronic respiratory disease that has become a global health problem. miRNAs play an important role in multiple immune and inflammatory diseases, including AR. In this work, the mechanism by which miR-224-5p regulates AR in vivo and in vitro was examined. Methods: Human nasal epithelial cells (HNEpCs) were used to establish an AR cell model induced by Der P1, and C57BL/6 mice were used to establish an AR animal model induced by OVA (ovalbumin). RT-qPCR was used to determine the level of miR-224-5p; western blot analysis was used to determine GATA3; ELISA was used to determine the levels of OVA-specific IgE, IFN-γ, IL-4, IL-5, and IL-13; flow cytometry was used to determine the differentiation of Th1 and Th2 cells; and HE and PAS staining was used to observe the histopathological alterations in the mouse nasal mucosa and spleen. Results: miR-224-5p was downregulated in nasal mucosa from mice with AR and an AR cell model. Overexpressed miR-224-5p can improve AR development and attenuate AR symptoms by regulating GATA3-mediated Th1/Th2 responses. Conclusion: miR-224-5p attenuates allergic reactions in mice with AR by regulating the Th1/Th2 response.

Immunomodulation in allergic rhinitis: Insights from Th2 cells and NLRP3/IL-18 pathway.

Allergic rhinitis (AR) is characterized by nasal symptoms such as rubbing and sneezing, often triggered by allergen exposure. The purpose of this study is to dissect the roles of NLRP3-mediated immune modulation and macrophage pyroptosis in modulating T cell differentiation within the context of ovalbumin (OVA)-induced AR in mice. OVA-induced AR was established in mice, evaluating nasal symptoms, macrophage infiltration, cytokine levels, and T cell differentiation. Manipulations using NLRP3-/-, ASC-/- mice, clodronate liposome treatment, and NLRP3 inhibitor MCC950 were performed to assess their impact on AR symptoms and immune responses. Following OVA stimulation, increased nasal symptoms were observed in the OVA group along with augmented GATA3 expression and elevated IL-4 and IL-1b levels, indicative of Th2 polarization and cellular pyroptosis involvement. NLRP3-/- and ASC-/- mice exhibited reduced CD3+ T cells post OVA induction, implicating cellular pyroptosis in AR. Macrophage depletion led to decreased IgE levels, highlighting their involvement in allergic responses. Further investigations revealed enhanced macrophage pyroptosis, influencing Th1/Th2 differentiation in AR models. IL-18 released through NLRP3-mediated pyroptosis induced Th2 differentiation, distinct from IL-1b. Additionally, MCC950 effectively mitigated AR symptoms by modulating Th2 responses and reducing macrophage infiltration. This comprehensive study unravels the pivotal role of NLRP3-mediated immune modulation and macrophage pyroptosis in Th1/Th2 balance regulation in OVA-induced AR. Targeting NLRP3 pathways with MCC950 emerged as a promising strategy to alleviate AR symptoms, providing insights for potential therapeutic interventions in AR management.

[Research progress of immune cell markers in allergic rhinitis for the evaluation of allergen immunotherapy].

Allergic rhinitis（AR） is a chronic inflammation of nasal mucosa mediated by IgE, which prevalence is increasing year by year. Allergen immunotherapy（AIT） has been proved to be effective in the treatment of AR. Patients can usually achieve satisfactory clinical remission after the standard course of treatment. At present, sIgE/tIgE is mainly used to evaluate the severity of allergy in patients with AR before immunotherapy, but there is no recognized biomarker for evaluating the efficacy of AIT. Based on the mechanism that immune cells participate in the formation of immune tolerance during AIT, this paper reviews the latest progress of immune cell markers in allergic rhinitis for the evaluation of the efficacy of AIT in recent years, in order to provide a more comprehensive evaluation basis for AR patients during immunotherapy.

Sphingosine Prevents Rhinoviral Infections.

Rhinoviral infections cause approximately 50% of upper respiratory tract infections and novel treatment options are urgently required. We tested the effects of 10 µM to 20 µM sphingosine on the infection of cultured and freshly isolated human cells with minor and major group rhinovirus in vitro. We also performed in vivo studies on mice that were treated with an intranasal application of 10 µL of either a 10 µM or a 100 µM sphingosine prior and after infection with rhinovirus strains 1 and 2 and determined the infection of nasal epithelial cells in the presence or absence of sphingosine. Finally, we determined and characterized a direct binding of sphingosine to rhinovirus. Our data show that treating freshly isolated human nasal epithelial cells with sphingosine prevents infections with rhinovirus strains 2 (minor group) and 14 (major group). Nasal infection of mice with rhinovirus 1b and 2 is prevented by the intranasal application of sphingosine before or as long as 8 h after infection with rhinovirus. Nasal application of the same doses of sphingosine exerts no adverse effects on epithelial cells as determined by hemalaun and TUNEL stainings. The solvent, octylglucopyranoside, was without any effect in vitro and in vivo. Mechanistically, we demonstrate that the positively charged lipid sphingosine binds to negatively charged molecules in the virus, which seems to prevent the infection of epithelial cells. These findings indicate that exogenous sphingosine prevents infections with rhinoviruses, a finding that could be therapeutically exploited. In addition, we demonstrated that sphingosine has no obvious adverse effects on the nasal mucosa. Sphingosine prevents rhinoviral infections by a biophysical mode of action, suggesting that sphingosine could serve to prevent many viral infections of airways and epithelial cells in general. Future studies need to determine the molecular mechanisms of how sphingosine prevents rhinoviral infections and whether sphingosine also prevents infections with other viruses inducing respiratory tract infections. Furthermore, our studies do not provide detailed pharmacokinetics that are definitely required before the further development of sphingosine.

An In Vitro Study Evaluating the Safety of Mesalazine on Human Nasoepithelial Cells.

Chronic rhinosinusitis (CRS) is a disease characterised by the inflammation of the nasal and paranasal cavities. It is a widespread condition with considerable morbidity for patients. Current treatment for chronic rhinosinusitis consists of appropriate medical therapy followed by surgery in medically resistant patients. Although oral steroids are effective, they are associated with significant morbidity, and disease recurrence is common when discontinued. The development of additional steroid sparing therapies is therefore needed. Mesalazine is a commonly used therapeutic in inflammatory bowel disease, which shares a similar disease profile with chronic rhinosinusitis. This exploratory in vitro study aims to investigate whether mesalazine could be repurposed to a nasal wash, which is safe on human nasoepithelial cells, and retains its anti-inflammatory effects. CRS patients' human nasal epithelial cells (HNECs) were collected. HNECs were grown at an air-liquid interface (ALIs) and in a monolayer and challenged with mesalazine or a non-medicated control. Transepithelial electrical resistance, paracellular permeability, and toxicity were measured to assess epithelial integrity and safety. The anti-inflammatory effects of mesalazine on the release of interleukin (IL)-6 and tumour necrosis factor alpha (TNF-α) were analysed using human leukemia monocytic cell line (THP-1). mesalazine did not impact the barrier function of HNEC-ALIs and was not toxic when applied to HNECs or THP-1 cells at concentrations up to 20 mM. mesalazine at 0.5 and 1 mM concentrations significantly inhibited TNF-α release by THP-1 cells. mesalazine effectively decreases TNF-α secretion from THP-1 cells, indicating the possibility of its anti-inflammatory properties. The safety profile of mesalazine at doses up to 20 mM suggests that it is safe when applied topically on HNECs.

Enhanced brain distribution of Ginsenoside F1 via intranasal administration in combination with absorption enhancers.

Ginsenoside F1 (GF1) is a potential drug candidate for the treatment of Alzheimer's disease. Nevertheless, its low oral bioavailability and poor solubility limit clinical application. By utilizing either a direct or indirect approach, intranasal administration is a non-invasive drug delivery method that can deliver drugs to the brain rapidly. But large molecule drug delivered to the brain through intranasal administration may be insufficient to reach required concentration for therapeutic effect. In this study, using GF1 as a model drug, the feasibility of intranasal administration in combination with absorption enhancers to increase brain distribution of GF1 was explored. First of all, the appropriate absorption enhancers were screened by in situ nasal perfusion study. GF1-HP-ß-CD inclusion complex was prepared and characterized. Thereafter, in vivo absorption of GF1 after intranasal or intravenous administration of its inclusion complex with/without absorption enhancers was investigated, and safety of the formulations was evaluated. The results showed that 2% Solutol HS 15 was a superior absorption enhancer. HP-ß-CD inclusion complex improved GF1 solubility by 150 fold. Following intranasal delivery, the absolute bioavailability of inclusion complex was 46%, with drug brain targeting index (DTI) 247% and nose-to-brain direct transport percentage (DTP) 58%. Upon further addition of 2% Solutol HS 15, the absolute bioavailability was increased to 75%, with DTI 315% and DTP 66%. Both nasal cilia movement and biochemical substances (total protein and lactate dehydrogenase) leaching studies demonstrated 2% Solutol HS 15 was safe to the nasal mucosa. In conclusion, intranasal administration combining with safe absorption enhancers is an effective strategy to enhance drug distribution in the brain, showing promise for treating disorders related to the central nervous system.

An overview of in vitro and in vivo techniques for characterization of intranasal protein and peptide formulations for brain targeting.

The surge in neurological disorders necessitates innovative strategies for delivering active pharmaceutical ingredients to the brain. The non-invasive intranasal route has emerged as a promising approach to optimize drug delivery to the central nervous system by circumventing the blood-brain barrier. While the intranasal approach offers numerous advantages, the lack of a standardized protocol for drug testing poses challenges to both in vitro and in vivo studies, limiting the accurate interpretation of nasal drug delivery and pharmacokinetic data. This review explores the in vitro experimental assays employed by the pharmaceutical industry to test intranasal formulation. The focus lies on understanding the diverse techniques used to characterize the intranasal delivery of drugs targeting the brain. Parameters such as drug release, droplet size measurement, plume geometry, deposition in the nasal cavity, aerodynamic performance and mucoadhesiveness are scrutinized for their role in evaluating the performance of nasal drug products. The review further discusses the methodology for in vivo characterization in detail, which is essential in evaluating and refining drug efficacy through the nose-to-brain pathway. Animal models are indispensable for pre-clinical drug testing, offering valuable insights into absorption efficacy and potential variables affecting formulation safety. The insights presented aim to guide future research in intranasal drug delivery for neurological disorders, ensuring more accurate predictions of therapeutic efficacy in clinical contexts.