Erchen decoction to reduce oxidative stress in dyslipidemia phlegm-dampness retention syndrome mice: In vivo mechanism revealed by metabolomics (liquid chromatography-mass spectrometry).

Objective: Erchen decoction, a traditional Chinese medicine formula, can reduce the level of oxidative stress for the treatment of dyslipidemia phlegm-dampness retention syndrome (DPDRS); however, studies have not elucidated the mechanism underlying its metabolic action. Here, liquid chromatography-mass spectrometry (LC-MS)-based metabolomic techniques were utilized to characterize the in vivo effects of Erchen decoction in achieving reduction of oxidative stress levels and understand the potential metabolic mechanisms of action.

Methods: We constructed a DPDRS animal model using a multifactorial composite modeling approach, and Erchen decoction was administered by gavage. We employed LC-MS-based metabolomic techniques in combination with serum-associated factors, gene transcription, methylation detection, and hematoxylin and eosin staining.

Results: In this study, the constructed animal model of DPDRS had satisfactory quality. Erchen decoction treatment reduced the levels of low-density lipoprotein cholesterol, t total cholesterol and riglyceride; it improved the endothelial structure, increased levels of serum β-nicotinamide adenine dinucleotide phosphate and glutathione concentrations, increased aortic phosphoserine aminotransferase and phosphoserine phosphatase gene expression levels, and decreased aortic phosphoglycerate dehydrogenase methylation level. A total of 64 differential metabolites were obtained using LC-MS assay, and 34 differential metabolic pathways were obtained after enrichment.

Conclusions: Erchen decoction treatment of DPDRS mice reversed lipid indexes, improved vascular endothelial structure, increased serum and aortic anti-oxidative stress factor concentration and expression levels, and decreased methylation levels, thereby reducing oxidative stress and protecting vascular endothelium. Tricarboxylic acid cycle and metabolic pathways of serum glutamine, serine, tryptophan, pyrimidine, and pyruvate were the most relevant metabolic pathways involved in reducing oxidative stress levels by Erchen decoction during DPDRS treatment; especially, mitochondrial redox homeostasis maintenance in endothelial cells may be crucial. In this work, the therapeutic potential of Erchen decoction for reducing the oxidative stress level in DPDRS was demonstrated; however, its in-depth mechanism is worth further exploration.