Salidroside Attenuates Airway Inflammation and Remodeling via the miR-323-3p/SOCS5 Axis in Asthmatic Mice

Abstract

Introduction: Salidroside (Sal) a bioactive component extracted from Rhodiola rosea is remarkable for its anti-asthmatic effects. The study aimed to explore the molecular mechanism of Sal in airway inflammation and remodeling in asthmatic mice and provide a novel theoretical basis for asthma treatment. Methods: An asthmatic mouse model was established via ovalbumin (OVA) treatment, followed by injection of Sal and transfection of miR-323-3p-mimic and sh- suppressor of cytokine signaling 5 (SOCS5). Expressions of miR-323-3p, SOCS5 mRNA, collagen (COL)-I, and COL-III were detected via reverse transcription quantitative polymerase chain reaction. SOCS5 protein level was detected via Western blot. Levels of IgE, IL-13, IL-4, and IL-5 were detected via enzyme-linked immunosorbent assay. Inflammatory cell infiltration was observed via hematoxylin-eosin staining. Collagen disposition was observed via Masson staining. Resistance index (RI) of airway hyperresponsiveness, and the number of total cells, inflammatory cells (eosinophil, macrophage, neutrophil, and lymphocyte) in bronchoalveolar lavage fluid (BALF) were observed. The binding relationship between miR-323-3p and SOCS5 was predicted through the RNA22 website and verified via dual-luciferase reporter assay. Results: miR-323-3p was highly expressed in OVA-treated mice. Sal treatment reduced inflammatory cell infiltration, COL disposition, miR-323-3p expression, and IgE, IL-13, IL-4, IL-5, COL-I, and COL-III levels, RI value, and the number of total cells and inflammatory cells in BALF. miR-323-3p inhibited SOCS5 transcription. miR-323-3p overexpression or SOCS5 downregulation reversed the protecting role of Sal in asthmatic mice. Conclusion: Sal inhibited miR-323-3p expression to promote SOCS5 transcription, thereby attenuating airway inflammation and remodeling in asthmatic mice.