ABSTRACT
This study used pharmacology combined with metabolomics to explore the effect of Amygdalus mongolica total extract on bleomycin induced pulmonary fibrosis in rats. The rat model of pulmonary fibrosis was established by intratracheal injection of bleomycin and treated with the total extract of Amygdalus mongolica. The pathological changes of lung tissue were evaluated by hematoxylin and eosin (HE) and Masson staining, the contents of superoxide dismutase (SOD) and malondialdehyde (MDA) in lung tissue were detected, and transforming growth factor β1 (TGF-β1), Smad family member 3 (Smad3), α-smooth muscle actin (α-SMA) pathway index expression in lung tissue was detected by fluorescence quantitative PCR. UPLC-Q-TOF/MS was used to study serum metabolomics to explore the changing patterns of biomarkers and the metabolic pathways affected by them. The results showed that compared with the model group, the medium (1.5 g·kg-1) and high (3.0 g·kg-1) doses of Amygdalus mongolica total extract could significantly reduce the lung index, significantly increase the activity of SOD in serum and lung tissue, reduce the degree of alveolar inflammation and pulmonary fibrosis, and reduce MDA in serum and lung tissue, and significantly reduce TGF-β1, Smad3, α-SMA mRNA expression in lung tissue. Serum metabolomics profile analysis identified 25 significantly different metabolites, the Amygdalus mongolica total extract can participate in linoleic acid metabolism, glycerophospholipid metabolism and alpha-linolenic acid metabolism by reducing five key biomarkers: lysoPE(0∶0/22∶5(4Z,7Z,10Z,13Z,16Z)), lysoPC(20∶0/0∶0), PC(20∶5(5Z,8Z,11Z,14Z,17Z)/15∶0), 12,13-dihydroxy-9-octadecenoic acid (12,13-DHOME), 9,10-dihydroxy-12-octadecenoic acid (9,10-DHOME) to affect pulmonary fibrosis. This study preliminarily revealed the action mechanism of Amygdalus mongolica total extract against pulmonary fibrosis in rats, and provided a reference basis for the clinical application of Amygdalus mongolica. The animal experiments were approved by the Medical Ethics Committee of Baotou Medical College (No.20170315).