The Singapore-led study, published in Molecular Nutrition & Food Research, tested the effect of the green tea compound (-)-epigallocatechin-3-gallate (EGCG) on the feeding behavior of mice fed a variety of diets, including a high-fat diet (HFD) that is known to induce overeating and lead to increased obesity risk.
“The hedonic properties of food rich in fat lead to overeating, irrespective of actual energy demands,” said the team – led by Hongyu Li from Agency for Science, Technology and Research (A*STAR), Singapore.
“The consumption of high-fat food directly influences the brain reward system and propagates a vicious phase of repetitive eating. This dysregulation results in excessive calorie intake and is a major causal factor in the prevalence of obesity.”
Li and colleagues noted that while many studies have suggested an anti-obesity effect for green tea and its extracts such as EGCG, much of this research has focused on proposed peripheral mechanisms related to the metabolism of body fat while very little has focused on a suggested central nervous mechanism that could result in altered eating behaviors and lower food intake.
“Little is known about its [EGCG] effect on HFD-induced alterations in feeding behavior,” commented Li et al.
“Our study demonstrates that EGCG supplement specifically counteracts daytime overeating induced by HFD in mice, suggesting its central role in regulating feeding behavior and energy homeostasis,” they revealed.
The Singapore-based study, which was jointly funded by A*STAR and Abbott Nutrition, split three groups of wildtype male mice (C57B/6j mice) in to three diet groups – normal chow diet; one week of high-fat diet (HFD) where fat made up 60% of energy; or three months of HFD. All groups were given an EGCG supplement regimen after the diets were administered.
While EGCG was found to have no effect on feeding behavior in normal chow diet group, Li and colleagues revealed that the habit of increased daytime feeding brought on by HFD was selectively corrected EGCG supplementation in both HFD groups.
This including reversed food intake, feeding frequency and meal size in the one week HFD plus EGCG group, and reduced food intake and feeding frequency in three month HFD plus EGCG group, said the authors.
“Moreover, EGCG treatment altered diurnally oscillating expression pattern of key appetite-regulating genes, including AGRP, POMC, and CART, and key circadian genes Clock and Bmal1 in hypothalamus of DIO mice, indicating its central effect on feeding regulation.”
“EGCG specifically counteracts HFD-induced alterations of feeding frequency, meal size, and circadian distribution, which partly restores a normal feeding pattern,” they concluded – adding that EGCG could offer an alternative approach to prevent and treat diet induced obesity.
Source: Molecular Nutrition & Food Research
Published online ahead of print, doi: 10.1002/mnfr.201600162
“Green tea (-)-epigallocatechin-3-gallate counteracts daytime overeating induced by high-fat diet in mice”
Authors: Hongyu Li, et al