Exploring the Preventive Potential of Solubilized Sturgeon Oil on Acute Infection with Respiratory Viruses

Acute respiratory viral infections (ARIs) are a major global cause of morbidity and mortality, posing significant threats to public health. Efforts to prevent and combat ARIs have focused on identifying suitable ingredients for nasal spray formulations targeting the nasal mucosa. However, issues such as foreign body sensation, irritation, discomfort, and safety concerns have emphasized the need for eco-friendly and safe ingredients derived from natural sources. In this study, we evaluated the efficacy of solubilized sturgeon oil (SSO), prepared as an oil-in-water nanoemulsion from Siberian sturgeon, in preventing ARIs via nasal spray administration. Pre-treatment via the intranasal route demonstrated that SSO effectively inhibited respiratory infections caused by SARS-CoV-2, influenza A virus (IAV), and respiratory syncytial virus (RSV), along with suppressing viral replication in both nasal and lung tissues. This suppression was associated with reduced pulmonary inflammation, as evidenced by decreased infiltration of inflammatory cells such as Ly-6C+ monocytes and Ly-6G+ neutrophils, as well as a reduction in pro-inflammatory cytokine production. Histopathological analyses further revealed that nasal administration of SSO significantly attenuated the progression of lung inflammation induced by viral infections. Notably, the protective effects of SSO against SARS-CoV-2, IAV, and RSV persisted for at least 6 h following nasal application. These findings underscore the potential of SSO as an eco-friendly and safe ingredient for inclusion in nasal spray formulations, offering significant promise as a primary defense against ARIs.