Effects of minerals and xylitol solution on human nasal epithelium: Water channels upregulation and potential anti-inflammatory properties.

OBJECTIVES: The nasal mucosa has a fundamental role in defending the respiratory system by filtering inhaled air, maintaining hydration, and regulating osmotic balance. This study aimed to evaluate the safety and potential benefits of an Investigational Product (IP), composed of saline solution 0.9%, minerals and xylitol 1%, on nasal epithelial cells using a reconstructed nasal epithelium model in vitro. METHODS: The IP's impact on key mediators such as Aquaporin-3 (AQP3), Adenosine Triphosphate (ATP), and Interleukin-8 (IL-8) synthesis was assessed. For comparison, specific positive controls were used for each cell viability and epithelium integrity assays, while saline solution 0.9% was applied as the negative control. RESULTS: Treatment with the IP resulted in a 64% increase in AQP3 expression, suggesting enhanced cellular hydration and osmotic balance. Moreover, the IP reduced ATP release by 36% on day-1 and 40% on day-4, indicating its potential to modulate epithelial responses to stress. Inflammatory cytokine IL-8 synthesis also decreased by 25% and 31% on days-1 and -4, respectively, when compared to the inflammatory induced group, supporting the IP's anti-inflammatory properties potential. Importantly, the IP did not induce cytotoxicity or irritative responses, maintaining cellular viability and integrity. CONCLUSION: These results suggest that the IP could be a promising therapeutic option for modulating inflammation and maintaining nasal epithelial function in inflammatory conditions, such as rhinitis and rhinosinusitis. Further in vivo studies and clinical trials are warranted to confirm these findings and to explore the therapeutic applicability of this product in nasal health management. LEVEL OF EVIDENCE: Level 5.