tectorigenin and Pulmonary-Fibrosis

The aim of this study was to evaluate the effect of tectorigenin on treating allergic asthma model of guinea pigs and investigate the underlying mechanisms.. Allergic asthma model of guinea pigs was established by sensitizing with ovalbumin (OVA). Then OVA-sensitized guinea pigs were injected with 10 mg/kg tectorigenin, 25 mg/kg tectorigenin or dexamethasone to investigate the effect of tectorigenin.. High dose of tectorigenin effectively decreased the number of coughs, the number of inflammatory cells and the levels of pro-inflammatory factors. Moreover, tectorigenin could inhibit pulmonary fibrosis in guinea pigs sensitized with OVA. In addition, the functions of tectorigenin were realized through downregulating profibrotic factors of transforming growth factor (TGF)-β1, phosphorylated (p)-Smad2/3 and Smad4, upregulating fibrosis-inhibitor of Smad7 and decreasing pro-inflammatory factors of vascular endothelial growth factor A (VEGFA), tumour necrosis factor-α (TNF-α), Toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88), p-inhibitor of nuclear factor-kappa B (NF-κB) kinase β (p-IKKβ) and NF-κB.. Tectorigenin could inhibit pulmonary fibrosis and airway inflammation through TGF-β1/Smad signalling pathway and TLR4/NF-κB signalling pathway. Therefore, tectorigenin might be a promising medicine to treat allergic asthma.

Topics: Animals; Anti-Inflammatory Agents; Asthma; Disease Models, Animal; Drug Discovery; Guinea Pigs; Isoflavones; NF-kappa B; Pulmonary Fibrosis; Signal Transduction; Smad Proteins; Toll-Like Receptor 4; Transforming Growth Factor beta1; Up-Regulation

Tectorigenin is one of the main components in rhizomes of Iris tectorum, which is traditionally used to treat disorders such as hepatic cirrhosis caused by fibrosis. Idiopathic pulmonary fibrosis (IPF), one of the most common interstitial lung diseases, is caused by accumulation of fibroblasts in lungs.. In this work we sought to examine the effects of tectorigenin on pulmonary fibroblasts in the IPF animal model and investigated the molecular mechanism (microRNA regulation) of tectorigenin treatment.. A well-known animal disease model of pulmonary fibrosis in rat was established by intratracheally instilling of bleomycin. In vitro cultured pulmonary fibroblasts in bleomycin-treated rats and in controls were treated with or without tectorigenin. Comparative analyses of cell proliferation, apoptosis and cell cycle of pulmonary fibroblasts in bleomycin-treated rats and in controls were performed. Expression of miR-338* and its candidate gene LPA1 related to IPF of tectorigenin-treated pulmonary fibroblasts in bleomycin-treated rats were further investigated.. Tectorigenin significantly inhibited the proliferation of pulmonary fibroblasts in bleomycin-treated rats but not in controls. However, no altered cell cycle and apoptosis of pulmonary fibroblasts in bleomycin-treated rats and in controls was observed after tectorigenin treatment. Tectorigenin remarkably enhanced miR-338* expression of pulmonary fibroblasts in bleomycin-treated rats and downregulated LPA1 in the protein level.. Tectorigenin inhibits the proliferation of pulmonary fibroblasts in vitro and enhances miR-338* expression, which might in turn downregulate LPA1. This indicates a potential inhibitory role of tectorigenin on the pathogenesis of IPF.

Topics: Animals; Cell Proliferation; Cells, Cultured; Disease Models, Animal; Fibroblasts; Gene Expression Regulation; Growth Inhibitors; Isoflavones; Lung; Male; MicroRNAs; Pulmonary Fibrosis; Rats; Rats, Sprague-Dawley