RESUMO
BACKGROUND & AIMS: Fibrotic changes seem to be responsible for the high mortality rate observed in patients with acute respiratory distress syndrome (ARDS). The present study aimed to determine whether resveratrol, a natural antioxidant polyphenol, had anti-fibrotic effects in the murine model of lipopolysaccharide (LPS)-induced pulmonary fibrosis. METHODS: Fibrosis was assessed by determination of collagen deposition, hydroxyproline and type I collagen levels in lung tissues. Development of epithelial-mesenchymal transition (EMT) was identified by the loss of E-cadherin accompanying by the acquisition of α-smooth muscle actin (α-SMA). Transforming growth factor (TGF)-ß1 content, levels of phosphorylated Smad2/Smad3 and Smad4, malondialdehyde (MDA) content, total antioxidant capacity (T-AOC), superoxide dismutase (SOD) activity, and catalase (CAT) activity in lung tissues were determined. RESULTS: LPS increased collagen deposition, hydroxyproline and type I collagen contents, and meanwhile induced EMT process, stimulated TGF-ß1 production and Smad activation in lung tissues on day 21 to day 28 after LPS administration. In addition, LPS treatment resulted in a rapid induction of oxidative stress as evidenced by increase of MDA and decreases of T-AOC, CAT and SOD activities as early as 7 days after LPS treatment, which was persistent for at least 4 weeks. In contrast, resveratrol treatment attenuated LPS-induced EMT and pulmonary fibrosis, meanwhile it suppressed LPS-induced oxidative stress, TGF-ß1 production and activation of Smad signaling pathway. CONCLUSIONS: Resveratrol may ameliorate LPS-induced EMT and pulmonary fibrosis through suppression of oxidative stress and TGF-ß1/Smad signaling pathway. Application of antioxidants may represent a useful adjuvant pharmacologic approach to reduce ARDS-associated pulmonary fibrosis.
Assuntos
Transição Epitelial-Mesenquimal/efeitos dos fármacos , Lipopolissacarídeos/efeitos adversos , Estresse Oxidativo/efeitos dos fármacos , Fibrose Pulmonar/tratamento farmacológico , Estilbenos/farmacologia , Fator de Crescimento Transformador beta1/genética , Animais , Catalase/metabolismo , Colágeno Tipo I/metabolismo , Modelos Animais de Doenças , Masculino , Malondialdeído/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Fibrose Pulmonar/induzido quimicamente , Resveratrol , Transdução de Sinais , Superóxido Dismutase/metabolismo , Fator de Crescimento Transformador beta1/metabolismoRESUMO
OBJECTIVE: To establish a new identification and analysis method of gypsum fibrosum, gypsum fibrosum praeparatum, pulvis talci and gypsum fibrosum blended with pulvis talci. METHODS: Powder X-ray diffraction fingerprint spectra method. RESULTS: Experiments and analysis were carried out on four samples. The standard X-ray diffraction fingerprint spectra and characteristic diffraction peaks of each sample were obtained. CONCLUSION: The experimental result indicates that X-ray diffraction fingerprint spectra can be used to identify and analyze gypsum fibrosum, gypsum fibrosum praeparatum, pulvis talci and gypsum fibrosum blended with pulvis talci.