Qingfei xieding prescription ameliorates mitochondrial DNA-initiated inflammation in bleomycin-induced pulmonary fibrosis through activating autophagy.

ETHNOPHARMACOLOGICAL RELEVANCE: Qingfei Xieding prescription was gradually refined and produced by Hangzhou Red Cross Hospital. The raw material includes Ephedra sinica Stapf, Morus alba L., Bombyx Batryticatus, Gypsum Fibrosum, Prunus armeniaca L. var. ansu Maxim., Houttuynia cordata Thunb. , Pueraria edulis Pamp. Paeonia L., Scutellaria baicalensis Georgi and Anemarrhena asphodeloides Bge. It is effective in clinical adjuvant treatment of patients with pulmonary diseases. AIM OF THE STUDY: To explore the efficacy and underlying mechanism of Qingfei Xieding (QF) in the treatment of bleomycin-induced mouse model. MATERIALS AND METHODS: TGF-ß induced fibrotic phenotype in vitro. Bleomycin injection induced lung tissue fibrosis mouse model in vivo. Flow cytometry was used to detect apoptosis, cellular ROS and lipid oxidation. Mitochondria substructure was observed by transmission electron microscopy. Autophagolysosome and nuclear entry of P65 were monitored by immunofluorescence. Quantitative real-time PCR was performed to detect the transcription of genes associated with mtDNA-cGAS-STING pathway and subsequent inflammatory signaling activation. RESULTS: TGF-ß induced the expression of α-SMA and Collagen I, inhibited cell viability in lung epithelial MLE-12 cells that was reversed by QF-containing serum. TGF-ß-mediated downregulation in autophagy, upregulation in lipid oxidation and ROS contents, and mitochondrial damage were rescued by QF-containing serum treatment, but CQ exposure, an autophagy inhibitor, prevented the protective role of QF. In addition to that, the decreased autophagolysosome in TGF-ß-exposed MLE-12 cells was reversed by QF and restored to low level in the combination treatment of QF and CQ. Mechanistically, QF-containing serum treatment significantly inhibited mtDNA-cGAS-STING pathway and subsequent inflammatory signaling in TGF-ß-challenged cells, which were abolished by CQ-mediated autophagy inhibition. In bleomycin-induced mouse model, QF ameliorated pulmonary fibrosis, reduced mortality, re-activated autophagy in lung tissues and restrained mtDNA-cGAS-STING inflammation pathway. However, the protective effects of QF in bleomycin-induced model mice were also abrogated by CQ. CONCLUSION: QF alleviated bleomycin-induced pulmonary fibrosis by activating autophagy, inhibiting mtDNA-cGAS-STING pathway-mediated inflammation. This research recognizes the protection role of QF on bleomycin-induced mouse model, and offers evidence for the potentiality of QF in clinical application for pulmonary fibrosis treatment.

Tetrandrine Ameliorates Airway Remodeling of Chronic Asthma by Interfering TGF-ß1/Nrf-2/HO-1 Signaling Pathway-Mediated Oxidative Stress.

Background: Imbalanced oxidative stress and antioxidant defense are involved in airway remodeling in asthma. It has been demonstrated that Tetrandrine has a potent role in antioxidant defense in rheumatoid arthritis and hypertension. However, the correlation between Tetrandrine and oxidative stress in asthma is utterly blurry. This study aimed to investigate the role of Tetrandrine on oxidative stress-mediated airway remolding. Materials and Methods: Chronic asthma was established by ovalbumin (OVA) administration in male Wistar rats. Histopathology was determined by HE staining. Immunofluorescence was employed to detect the expression of α-SMA and Nrf-2. Level of oxidative stress and matrix metalloproteinases were examined by ELISA kits. Cell viability and cell cycle of primary airway smooth muscle cells (ASMCs) were evaluated by CCK8 and flow cytometry, respectively. Signal molecules were detected using western blot. Results: Tetrandrine effectively impairs OVA-induced airway inflammatory and airway remodeling by inhibiting the expression of CysLT1 and CysLTR1. The increase of oxidative stress and subsequent enhancement of MMP9 and TGF-ß1 expression were rescued by the administration of Tetrandrine in the rat model of asthma. In in vitro experiments, Tetrandrine markedly suppressed TGF-ß1-evoked cell viability and cell cycle promotion of ASMCs in a dose-dependent manner. Furthermore, Tetrandrine promoted Nrf-2 nuclear transcription and activated its downstream HO-1 in vivo and in vitro. Conclusion: Tetrandrine attenuates airway inflammatory and airway remodeling in rat model of asthma and TGF-ß1-induced cell proliferation of ASMCs by regulating oxidative stress in primary ASMCs, suggesting that Tetrandrine possibly is an effective candidate therapy for asthma.