Mechanism of miR-16-5p alleviates airway inflammation in asthma rats by targeting the TXNIP/NLRP3 signaling axis

Objective To investigate the mechanism of miR-16-5p alleviates ovalbumin (OVA)-induced airway inflammation in asthmatic rats by targeting thioredoxin-interacting protein (TXNIP)/NOD-like receptor thermoprotein structural domain-related protein 3 (NLRP3) signaling axis.Methods Male Sprague-Dawley rats were randomly divided into the control, model, miR-16-5p mimic, NC mimic, miR-16-5p inhibitor, and NC inhibitor groups, with 6 rats in each group. A mixture of 10% OVA and 10% aluminum hydroxide was used for sensitization, and 4% OVA was given by nebulized inhalation to stimulate asthma. Dual luciferase reporter assay was performed to verify the target binding relationship; microscopic was used to observe inflammatory cell numbers in bronchoalveolar lavage fluid (BALF); ELISA was used to detect IL-1β, IL-6, TNF-α, and MCP-1 levels; H&E staining was used to observe morphological changes of lung tissue; Masson staining was used to observe bronchial collagen deposition; Immunohistochemical staining was used to detect TXNIP and NLRP3 expression; Western blot was used to detect TXNIP, NLRP3, ASC, cleaved-caspase-1, and IL-1β proteins expression.Results Luciferase reporter assay showed that miR-16-5p could target and regulate TXNIP. Compared with the control group, the model group rats had damaged lung tissues, thickened airway walls, and massive collagen deposition; an increased number of inflammatory cells, significantly higher expression levels of IL-1β, IL-6, TNF-α and MCP-1 (p < 0.05); TXNIP, NLRP3, ASC, cleaved-caspase-1, and IL-1β protein expression levels were significantly elevated in lung tissues (p < 0.05). Compared with the model group, lung histopathological damage was significantly improved in asthmatic rats after overexpression of miR-16-5b, and collagen deposition was reduced; the number of inflammatory cells was decreased; the levels of IL-1β, IL-6, TNF-α and MCP-1 were significantly reduced (p < 0.05); the levels of TXNIP, NLRP3, cleaved-caspase-1, and IL-1β protein expression levels were significantly reduced (p < 0.05). MiR-16-5p inhibitor further aggravated the airway inflammatory response in asthmatic rats.Conclusion miR-16-5p can alleviate airway inflammation in asthmatic rats by targeting the TXNIP/NLRP3 signaling axis.