Effect of adjunctive sodium hyaluronate versus surfactant nasal irrigation on mucociliary clearance in allergic rhinitis: a single-blind, randomised, controlled study

Comprehensive evaluation of xylometazoline hydrochloride formulations: Ex-vivo and in-vitro studies

Xylometazoline is a well-established nasal decongestant that has been used alone and in combination with dexpanthenol as an over the counter (OTC) medicine. Considering the possibility of further improvement of xylometazoline nasal formulations, hyaluronic acid (HA) was evaluated as an additional ingredient. The aim of this study was to investigate the permeation, mucosal retention, and mucoadhesion properties of a new xylometazoline-HA [Xylo-HA] formulation ex vivo and to explore the potential benefits of incorporating HA in the formulation in vitro. Sheep nasal mucosa was used in the ex vivo study, where Xylo-HA was compared with xylometazoline alone [Xylo-Mono], and in combination with dexpanthenol [Xylo-Dex] to understand the impact of formulation changes. The permeation of xylometazoline was generally low (Xylo-Mono 11.14 ± 4.75 %, Xylo-HA 14.57 ± 5.72 % and Xylo-Dex 11.00 ± 3.05 % of the applied dose). The steady state fluxes of xylometazoline were determined as 12.64 ± 3.52 μg/cm2h, 14.94 ± 3.38 μg/cm2h and 12.19 ± 2.05 μg/cm2h for Xylo-Mono, Xylo-HA and Xylo-Dex, respectively. No significant differences were observed between the formulations in the permeation nor mucosal retention studies (p > 0.05 for all), while Xylo-HA exhibited superior mucoadhesive proprieties (p < 0.05 for all). The effects on wound healing and barrier integrity of the three xylometazoline formulations were tested in vitro on HaCaT cells. To better elucidate the role of HA, an additional HA formulation without xylometazoline was prepared (HA-Mono). A scratch test was performed to evaluate wound healing, revealing that the test formulations did not achieve complete wound closure within 72 h and demonstrated a similar effect at the end of the testing period. To assess the effect on barrier integrity, cells were treated for 5 days with daily measurements of transepithelial electrical resistance (TEER). At the end of the experiment, Xylo-Dex showed a moderate 14 % increase in TEER, while Xylo-Mono did not significantly affect this parameter. TEER rose by 951 % in the Xylo-HA, and by 10497 % in the HA group, suggesting that incorporating HA led to enhanced barrier function. Further clinical studies are recommended to better understand the clinical implications and efficacy of the Xylo-HA formulation, with particular focus on the role of HA.

Inter-societal Delphi Consensus on the topical nasal treatments in Italy

Topical nasal therapy is widely used in clinical practice by different specialists. However, it is multifaceted and still controversial. Namely, there is no consensus about the many aspects, and there needs to be specific guidelines. Four independent experts involved 14 Italian scientific societies (concerning ENT, allergy, and pediatrics areas) to participate in generating an Intersocietal Delphi Consensus on this matter. Three iterative rounds collected experts (4 in the first round, 20 in the second round, and 45 in the third round) designed by the scientific societies based on their clinical expertise and documented scientific value. Thirty-four statements were discussed and voted on. At the second round, all statements accomplished a very high consensus grade (>95%). At the third round, many statements reached a high or very high grade of consensus (>70%). However, some statements did not obtain sufficient agreement. Consequently, there is a need to implement knowledge about this issue through educational initiatives and new studies conducted with a robust methodology. In conclusion, topical nasal therapy deserves adequate knowledge as it is widespread and fruitful in managing upper respiratory diseases.

Factors influencing airway smooth muscle tone: a comprehensive review with a special emphasis on pulmonary surfactant

A thin film of pulmonary surfactant lines the surface of the airways and alveoli, where it lowers the surface tension in the peripheral lungs, preventing collapse of the bronchioles and alveoli and reducing the work of breathing. It also possesses a barrier function for maintaining the blood-gas interface of the lungs and plays an important role in innate immunity. The surfactant film covers the epithelium lining both large and small airways, forming the first line of defense between toxic airborne particles/pathogens and the lungs. Furthermore, surfactant has been shown to relax airway smooth muscle (ASM) after exposure to ASM agonists, suggesting a more subtle function. Whether surfactant masks irritant sensory receptors or interacts with one of them is not known. The relaxant effect of surfactant on ASM is absent in bronchial tissues denuded of an epithelial layer. Blocking of prostanoid synthesis inhibits the relaxant function of surfactant, indicating that prostanoids might be involved. Another possibility for surfactant to be active, namely through ATP-dependent potassium channels and the cAMP-regulated epithelial chloride channels [cystic fibrosis transmembrane conductance regulators (CFTRs)], was tested but could not be confirmed. Hence, this review discusses the mechanisms of known and potential relaxant effects of pulmonary surfactant on ASM. This review summarizes what is known about the role of surfactant in smooth muscle physiology and explores the scientific questions and studies needed to fully understand how surfactant helps maintain the delicate balance between relaxant and constrictor needs.

Efficacy of hyaluronic acid in the treatment of nasal inflammatory diseases: a systematic review and meta-analysis

Background: Hyaluronic acid (HA), the main component of the extracellular matrix, has the ability to promote tissue repair and regulate inflammation. It is used in otolaryngology as an adjuvant treatment to alleviate postoperative nasal symptoms. However, there is currently insufficient evidence demonstrating the therapeutic efficacy of HA for patients with nasal inflammatory diseases (NIDs). Therefore, this study aimed to evaluate the efficacy and safety of topical HA in the treatment of NID patients without receiving surgery. Methods: In this meta-analysis, comprehensive searches were conducted in PubMed, Embase, the Cochrane Central Register of Controlled Trials, and Web of Science. Keywords searched included "hyaluronic acid," "sinusitis," "allergic rhinitis," "rhinitis," and "randomized controlled trials (RCTs)." The Cochrane Collaboration's "Risk of Bias Assessment" tool was used to assess the quality of the included trials, and the meta-analysis was performed using the RevMan 5.3 and STATA 15 statistical software. Results: A total of 11 articles and 825 participants were enrolled. For the primary outcomes, the pooled results revealed that HA significantly improves nasal obstruction (SMD, -0.53; 95% CI, -0.92 to -0.14; p = 0.008; and I2 = 79%) and rhinorrhea (SMD, -0.71; 95% CI, -1.27 to -0.15; p = 0.01; and I2 = 90%) in patients with NIDs. As for the secondary outcomes, the pooled results demonstrated that when compared with the control group, HA could significantly improve nasal endoscopic scores (p < 0.05), rhinitis scores (p < 0.05), rhinomanometry (p < 0.05), nasal neutrophils (p < 0.05), and mucociliary clearance (p < 0.05). However, no significant differences were observed between the two groups regarding nasal itching, sneezing, hyposmia, quality-of-life scores, and nasal eosinophils. For the risk of bias, 54.5% and 45.5% of trials had a low risk of bias in the randomization process and deviation of the intended intervention, respectively. Conclusion: In the present study, the results reveal that HA might ameliorate symptoms of patients with NIDs. However, more clinical trials with larger participant cohorts are required to confirm this result. Systematic review registration number: clinicaltrials.gov, identifier CRD42023414539.

Hyaluronic Acid in Rhinology: Its Uses, Advantages and Drawbacks-A Review

Hyaluronic acid has been increasingly involved in recent research due to its many chemical and physical properties. This is a review of the literature for studies involving the use of hyaluronic acid in rhinology. Hyaluronic acid washes and irrigation have been increasingly used in chronic sinusitis medical therapy and post-operatively with mixed results. It has also been shown to play a role in the treatment of nasal polyposis, allergic rhinitis, acute rhinosinusitis and empty nose syndrome. Its effect on biofilm in many disease entities has also been studied. HA is being recently used as ancillary treatment for several rhinologic conditions such as post-operative endoscopy care and chronic sinonasal infections. The properties of HA have intrigued researchers over the past years particularly in biofilm management, healing and inflammation.