Zeaxanthin attenuates OVA-induced allergic asthma in mice by regulating the p38 MAPK/β-catenin signaling pathway

Abstract

Background: Asthma is a heterogeneous and complex chronic airway disease with a high incidence rate, characterized by chronic airway inflammation. Although the anti-inflammatory effect of zeaxanthin has been demonstrated in various disease models, its explicit role in allergic asthma remains elusive. Methods: An allergic asthma model was established by ovalbumin (OVA) stimulation in BALB/c nude mice. The pathological examination, collagen deposition and expression of α-smooth muscle actin (α-SMA) in lung tissues were determined by hematoxylin and eosin (H&E), MASSON and immunofluorescence staining, respectively. Besides, the effect of zeaxanthin on inflammation and oxidative stress was assessed by the enzyme-linked immunosorbent assay (ELISA) and spectrophotometry measure. Moreover, the underlying mechanism was analyzed by detecting the expression of phosphorylated p38 (p-p38), p38, β-catenin, p-c-Jun N-terminal kinase (p-JNK) and JNK with western blot assays. Results: The distinct infiltration of inflammatory cells was observed in the OVA-induced asthma mice model with significantly increased concentrations of immunoglobulin E (IgE), interleukin-4 (IL-4), IL-5, IL-13 and eotaxin (p˂0.001), which were prominently reversed by zeaxanthin treatment (p˂0.001). In addition, zeaxanthin treatment decreased the OVA-induced collagen deposition and α-SMA expression. A similar inhibitory effect of zeaxanthin on the oxidative stress was also observed in the OVA-induced asthma mice model, as evidenced by the prominent decrease of malondialdehyde (MDA) concentration and the remarkable increase of superoxide dismutase (SOD), glutathione S transferase (GST) and Glutathione (GSH) concentrations (p˂0.001). Moreover, zeaxanthin introduction markedly reduced the relative expressions of p-p38/p38, β-catenin and p-JNK/JNK in the OVA-induced asthma mice model (p˂0.001), indicating that zeaxanthin suppressed the p38 mitogen-activated protein kinase (p38 MAPK)/β-catenin signaling pathway in the OVA-induced asthma mice model. Conclusions: Zeaxanthin attenuated OVA-induced allergic asthma in mice via modulating the p38 MAPK/β-catenin signaling pathway.