Poster Topical Area: Dietary Bioactive Components
Location: Hall D
Poster Board Number: 280
Green coffee bean extract (GCBE) is used for weight management and reports suggest that its effect on weight control is associated with its major phenolic compounds, chlorogenic acids. However, there are different reports of the efficacy between GCBE and chlorogenic acids on fat accumulation. Since GCBE is ~50% of chlorogenic acids, among which 3-O-caffeoylquinic acid (3-CQA) is one main form, we investigated the mechanism of actions of GCBE and 3-CQA on fat accumulation using Caenorhabditis elegans. Treatment with GCBE (5 mg/mL) and 3-CQA (2.65 mg/mL) significantly reduced fat accumulation by 29% and 23%, respectively, compared to the control. The effects of GCBE and 3-CQA on fat accumulation were abolished in mutants of sbp-1 (an ortholog of mammalian sterol-regulatory-element-binding protein) and daf-16 (an ortholog of mammalian Forkhead box O transcription factor), which suggests that both sbp-1 and daf-16 are important genes in GCBE and 3-CQA's effects on fat metabolism. We further confirmed that GCBE and 3-CQA induced nuclear translocation of DAF-16 and significantly reduced the expression of sbp-1 and pod-2 (a homolog of acetyl-CoA carboxylase), a downstream target of sbp-1. Therefore, these results suggest that GCBE and 3-CQA reduce fat accumulation via SBP-1 and DAF-16 dependent mechanism in C. elegans, which are involved in lipogenesis and the insulin-signaling pathway, respectively. These results suggest that chlorogenic acids are most likely responsible for GCBE's effects on fat metabolism.
This work was financially supported by CNPq, Conselho Nacional de Desenvolvimento Científico e Tecnológico - Brasil [National Counsel of Technological and Scientific Development - Brazil].
University of Massachusetts Amherst