NMR-based metabonomic study of Chinese medicine Gegen Qinlian Decoction as an effective treatment for type 2 diabetes in rats

Metabonomic profiles of the type 2 diabetic rats induced by streptozotocin and high-sugar, high fat diet on the treatment of Gegen Qinlian Decoction (GQD) for 9 weeks were investigated. Rats were randomly divided into five groups: normal control (NC), type 2 diabetes (DM), metformin hydrochloric, GQD in high and low dosages. Plasma samples for ¹H NMR-based metabolomic research, serum samples for clinical biochemistry, and liver and pancreas tissues for histopathology test were collected. Compared with NC rats, metabolic pathways of DM rats were revealed to be altered by pattern analyses of plasma NMR data, which was further correlated with serum biochemistry. Cross-validated scores mean trajectory derived from PLS-DA of NMR spectra demonstrated that GQD significantly restored the abnormal metabolic state in the long run, more potent than metformin hydrochloric. Detailed analysis of the altered metabolite levels indicated that GQD significantly ameliorated the disturbance in glucose metabolism, tricarboxylic acid cycle, lipid metabolism, amino acid metabolism and gut microbial metabolism and N-acetyl group metabolism. The results confirmed the hypoglycemic efficacy of GQD and its ability to ameliorate the diabetic symptoms in a global scale. NMR-based metabonomics approach is helpful for the further understanding of diabetes-related mechanisms.