Anthocyanins Inhibit Airway Inflammation by Downregulating the NF-κB Pathway via the miR-138-5p/SIRT1 Axis in Asthmatic Mice

Abstract

Objective: Asthma, caused by chronic inflammation, is a common disease. Anthocyanins are involved in asthma treatment. This study explored the mechanism of anthocyanins on airway inflammation in asthmatic mice by regulating nuclear factor-κB (NF-κB) via the miR-138-5p/sirtuin-1 (SIRT1) axis. Methods: The asthmatic mouse model was established by ovalbumin (OVA) induction and treated with anthocyanins or simultaneously injected with the lentivirus miR-138-5p mimic, followed by the measurement of lung inflammatory injury and IL-4, IL-5, IL-13, and IFN-γ levels in bronchoalveolar lavage fluid. Human bronchial epithelial (HBE) cells 16HBE14o-160 were induced by OVA to establish an asthmatic cell model, treated with anthocyanins and manipulated with miR-138-5p mimic and pcDNA3.1-SIRT1. The releases of inflammatory cytokines, the nuclear translocation of p-p65/p65 in the NF-κB pathway, and the levels of miR-138-5p and SIRT1 mRNA were detected. Results: In vivo experiments showed that anthocyanins could reduce the OVA-induced airway hyperresponsiveness and airway inflammation, improve the inflammatory infiltration and mucus in lung tissues, and diminish the miR-138-5p level in asthmatic mice. Infection with the miR-138-5p mimic averted the remission effect of anthocyanins in asthmatic mice. In vitro experiments showed that in HBE cells exposed to OVA, anthocyanins reduced the miR-138-5p level, increased the SIRT1 level, inhibited the release of inflammatory factors, and reduced the nuclear translocation of NF-κB p65. miR-138-5p targeted SIRT1. miR-138-5p overexpression partially reversed the therapeutic effect of anthocyanins, while SIRT1 overexpression antagonized the effect of miR-138-5p overexpression. Conclusion: Anthocyanins inhibited the NF-κB pathway by regulating the miR-138-5p/SIRT1 axis, thus inhibiting airway inflammation in asthmatic mice.