Ameliorative effects of the Coptis inflorescence extract against lung injury in diabetic mice by regulating AMPK/NEU1 signaling

In diabetic patients, complications are the leading cause of death and disability, while diabetic lung damage has received little research. The Coptis inflorescence extract (CE) has hypoglycemic properties, but the mechanism of its protective role on diabetic lung injury is understood.This study aims to explore the protective actions and molecular mechanism of CE and its active ingredients in diabetic lung disease.Twenty-nine metabolites were identified in the metabolomic profile of CE using HPLC-ESI/MS, and high-content substances of berberine (BBR) and linarin (LIN) were isolated from CE using column chromatography. The potential targets and molecular mechanisms of CE against diabetic lung damage were systematically investigated by network pharmacology and in vitro experimental validation.CE significantly improved lung function and pathology. CE (360 mg/kg) or metformin treatment significantly improved lipid metabolism disorders, including decreased HDL-C and elevated serum TG, TC, and LDL-C levels. Furthermore, CE's chemical composition was determined using the HPLC-QTOF-MS method. CE identified five compounds as candidate active compounds (Berberine, Linarin, Palmatine, Worenine, and Coptisine). Network pharmacology analysis predicted CE contained five active compounds and target proteins, that AMPK, TGFβ1, and Smad might be the key targets in treating diabetic lung injury. Then we investigated the therapeutic effect of bioactive compounds of CE on diabetic lung damage through in vivo and in vitro experiments. Intragastric administration with BBR (50 mg/kg) or LIN (20 mg/kg) suppressed weight loss, hyperglycemia, and dyslipidemia, significantly alleviating lung inflammation in diabetic mice. Further mechanism research revealed that LIN or BBR inhibited alveolar epithelial-mesenchymal transition induced by high glucose by regulating AMPK/NEU-mediated signaling pathway.In conclusion, the administration of CE can effectively alleviate diabetic lung damage, providing a scientific basis for lowering blood sugar to moisturize lung function. BBR and LIN, the main components of CE, can effectively alleviate diabetic lung damage by regulating AMPK/NEU1 Signaling and inhibiting the TGF-β1 level, which may be a critical mechanism of its effects.