Inhalation of panaxadiol alleviates lung inflammation via inhibiting TNFA/TNFAR and IL7/IL7R signalling [Mouse]
Background: There are no highly effective medications for treating pneumonia. Ginseng and its derivatives have anti-inflammatory properties, but their unstable physicochemical and metabolic properties prevent them from being used to treat pneumonia. The aforementioned issues may be resolved by inhalation, but the precise mechanism of action must be investigated.  Methods: In order to study the effects and mechanisms of PD inhalation drug delivery, models of LPS-induced murine holistic pneumonia, isolated macrophage inflammation, and epithelial cell co-culture are utilized. For the evaluation of efficacy, pathology and molecular assays have been utilized. Mechanisms of action and targets were screened and validated by molecular means using transcriptome sequencing. Efficacy and mechanism of action were ultimately validated using human BALF cell models. Also studied were pharmacokinetic parameters of inhaled PD.  Results: Inhalation of PD dose-dependently reduced LPS-induced lung inflammation in mice, including inflammatory cell infiltration, lung histopathology, and inflammatory factor expression. Oral PD had the same anti-inflammatory effect as inhalation, but inhalation was more effective at the same dose. It could be a result of its increased bioavailability and improved pharmacokinetic parameters. Using transcriptome analysis and validation of macrophage and epithelial cell experiments, we discovered that PD may inhibit TNFA/TFNAR and IL7/IL7R signaling to inhibit macrophage inflammatory factor-induced epithelial cell apoptosis and promote value-added initiation. Human alveolar lavage cell experimentation confirmed this result.  Conclusion: PD inhalation alleviates lung inflammation and pathology by inhibiting TNFA/TFNAR and IL7/IL7R signaling. PD may be a novel drug for the clinical treatment of lung inflammation. Overall design: Animals were randomly divided into 3 groups (n = 6 in each group): control (sterile saline [0.9% NaCl]), model (LPS 50 µg/mouse), E (LPS+PD (10 mg/mL, inhalation [ih.])).  For the inhaled group, mice were put into an inhalation box connect with a aerosol device (PARIBOY SX, Germany) .