Double-blinded, randomized clinical trial of Gegen Qinlian decoction pinpoints as key gut bacteria in alleviating hyperglycemia.

BACKGROUND

Accumulating evidence suggests that metabolic disorders, including type 2 diabetes mellitus (T2DM), can be treated with traditional Chinese medicine formulas, such as the Gegen Qinlian decoction (GQD). This study elucidates the mechanisms by which gut microbes mediate the anti-diabetic effects of GQD.

METHODS

We conducted a double-blind randomized clinical trial involving 120 untreated participants with T2DM. During the 12-week intervention, anthropometric measurements and diabetic traits were recorded every 4 weeks. Fecal microbiota and serum metabolites were measured before and after the intervention using 16S rDNA sequencing, liquid chromatography-mass spectrometry, and Bio-Plex panels.

RESULTS

Anti-diabetic effects were observed in the GQD group in the human trial. Specifically, glycated hemoglobin, fasting plasma glucose, and two-hour postprandial blood glucose levels were significantly lower in the GQD group than in the placebo group. Additionally, was significantly enriched in the GQD group, and the short-chain fatty acid levels were higher and the serum inflammation-associated marker levels were lower in the GQD group compared to the placebo group. Moreover, abundance negatively correlated with the levels of serum hemoglobin, fasting plasma glucose, and pro-inflammatory cytokines. Finally, the diabetes-alleviating effect of was confirmed by oral administration of (DSMZ 17677) in T2DM mouse model.

CONCLUSIONS

GQD improved type 2 diabetes primarily by modulating the abundance of in the gut microbiota, alleviating metabolic disorders and the inflammatory state.

TRIAL REGISTRATION

Registry No. ChiCTR-IOR-15006626.