Cuscuta chinensis Lam. extracts ameliorate type 2 diabetes by regulating metabolism and gut microbiota

<i>Cuscuta chinensis</i> Lam. (TSZ), a medicinal and edible plant, contains bioactive constituents including flavonoids, phenolic acids, polysaccharides, and lignans. This study investigated the effects of TSZ extracts in rats with type 2 diabetes mellitus (T2DM). We employed UV and UPLC-Q-TOF-MS/MS for compositional analysis, and integrated metabolomics with 16S rDNA sequencing to explore systemic responses. The results showed that TSZ extracts are rich in flavonoids and phenolic acids. Treatment with TSZ significantly regulated blood glucose and body weight, ameliorated metabolic disturbances, and influenced key pathways, including the biosynthesis of unsaturated fatty acids (e.g., oleic acid and α-linolenic acid). Further, TSZ reversed the gut microbiota dysbiosis in diabetic rats. Finally, Spearman correlation analysis indicated a close relationship between microbiota and metabolites. Collectively, the findings suggest that TSZ alleviates T2DM by modulating endogenous metabolic pathways and gut microbiota, which serve as potential targets for TSZ to enhance its glycemic effects in T2DM.