The Incretin Effect of Yerba Maté (Ilex paraguariensis) Is Partially Dependent on Gut-Mediated Metabolism of Ferulic Acid.

BACKGROUND/

OBJECTIVES

Yerba maté (YM), a traditional herbal beverage made from Ilex paraguariensis, contains bioactive compounds like polyphenols and alkaloids known for their metabolic benefits. This study investigates YM's incretin effects, focusing on glucagon-like peptide-1 (GLP-1) and gastric inhibitory polypeptide (GIP).

Methods

Male and female C57BL/6 mice were supplemented with YM for four weeks. Post-supplementation, GLP-1 and GIP gene expression levels were analyzed in jejunal mucosa, and plasma hormone concentrations were measured. Additionally, in vitro experiments were conducted using GLUTag L-cells to evaluate the direct effects of YM and its metabolites, including ferulic acid and dihydroferulic acid, on GLP-1 secretion. Gene expression analysis involved quantitative real-time PCR, while hormone levels were assessed via ELISA.

RESULTS

YM supplementation significantly increased GLP-1 gene expression and plasma GLP-1 levels compared to controls, with no changes observed in GIP expression or plasma levels. Direct treatment of GLUTag L-cells with YM did not enhance GLP-1 secretion. However, dihydroferulic acid, a microbial metabolite of ferulic acid, markedly stimulated GLP-1 production in L-cells, highlighting a role of gut-mediated metabolism in YM's incretin effects.

CONCLUSIONS

YM selectively upregulates GLP-1 pathways without affecting GIP, likely through gut-mediated mechanisms. These findings suggest YM as a promising nutraceutical for incretin modulation and metabolic disorder management. Further studies should explore the interplay between YM, the gut microbiota, and incretin pathways to fully realize its therapeutic potential.