Salidroside Mitigates Airway Inflammation in Asthmatic Mice via the AMPK/Akt/GSK3β Signaling Pathway

Introduction: This study aimed to explore the effects and mechanisms of salidroside (SAL) in airway inflammation in asthmatic mice. Methods: Mice were sensitized with ovalbumin (OVA) to establish an asthma model. They were divided into the control group, OVA group, SAL low-dose group (SAL-L), SAL high-dose group (SAL-H), and dexamethasone (DXM) group. The airway reactivity of the mice was measured, and the total cells, neutrophils, eosinophils, and lymphocytes were counted, respectively. The levels of IL-4, IL-5, IL-13, and IFN-gamma in bronchoalveolar lavage fluid (BALF) were detected by ELISA. Immunohistochemistry was used to detect the expression levels of p-AMPK, p-Akt, and p-GSK3 beta. Western blot was used to detect cytokine levels in lung tissue and p-AMPK, p-Akt, and p-GSK3 beta levels in LPS-induced 16HBE cells. Results: The airway hyperresponsiveness of asthmatic mice in the SAL-H group decreased (p < 0.05), and the total number of cells, neutrophils, eosinophils, and lymphocytes decreased significantly (p < 0.05). In addition, the airways of mice showed airway inflammatory infiltration and goblet cell proliferation, and the corresponding cellular inflammatory factors IL-4, IL-5, and IL-13 were significantly decreased. However, the expression of IFN-gamma in BALF and lung tissues was increased (p < 0.05). Moreover, after the mice were treated with SAL, the phosphorylation level of AMPK was significantly increased, which further reduced the phosphorylation levels of Akt and GSK3 beta (p < 0.05). Both SAL and AMPK inhibitors exerted effects on LPS-induced 16HBE cells, consistent with in vivo results. Conclusion: SAL can inhibit bronchial hyperresponsiveness and reduce tracheal inflammation by increasing AMPK phosphorylation and inhibiting Akt and GSK3 beta signaling pathways.