Apple polyphenol extracts and depression-like behavior in mice on high-sugar diets
What it found
In mice fed high-sugar diets, apple polyphenol extracts reduced depression-like behaviors and lowered stress hormones.
The treatment also improved gut bacteria balance and bile acid levels.
What they found
Animal and lab studies
Depression-like behavior in mice
Mice on both constant and alternating high-sugar diets developed depression-like behaviors. Apple polyphenol extracts significantly reduced these behaviors in the animals.
Stress hormones in mice
The extract lowered blood levels of two stress hormones, corticosterone and adrenocorticotrophic hormone, in mice on high-sugar diets.
Tissue damage in mice
Apple polyphenol extracts reduced tissue damage in the liver, colon, and brain of mice eating high-sugar diets. They also raised levels of proteins that help maintain gut barriers.
Gut bacteria changes in mice
In mice, the extract changed gut bacteria by lowering the ratio of Firmicutes to Bacteroidota. It also increased certain bacterial groups while reducing others like Dubosiella.
Bile acids in mice
The treatment lowered total bile acids in the blood and stool of mice. It also changed the types of bile acids present, especially glycocholic acid and isolithocholic acid.
What the authors conclude
- They suggest apple polyphenol extracts could be a useful supplement for easing depression caused by high-sugar diets.
- The authors explain this effect works through changes in bile acid circulation along the liver-gut-brain pathway.
How it was done
High-sugar diets are linked to depression, but scientists have not fully explored how apple polyphenol extracts might work against this effect.
Fifty-four male mice aged 5 weeks were split into five groups. Some ate a standard diet, others ate constant or alternating high-sugar diets. Two high-sugar groups received 500 mg per kg of body weight of apple polyphenol extract.
What it can’t tell you
- We summarised it from the abstract only.
- These results come from mice, so they cannot show what happens in people eating apples or apple extracts.
- A study in animals cannot prove that apple polyphenols will reduce depression in humans.
Who paid
- Authors work at
- Suzhou Medical College of Soochow University, China; Taizhou Central Hospital (Taizhou University Hospital), China
The paper
- Title
- Apple Polyphenol Extracts Attenuated Depressive-Like Behaviors of High-Sucrose Diet Feeding Mice by Farnesoid X Receptor-Mediated Modulation of Bile Acid Circulation within the Liver-Gut-Brain Axis
- Type
- Study
- Evidence
- Animals and lab studies
- Summarised from
- Abstract only
- Cite
- Xie Y, Shang S, Luan W, et al (2024). Apple Polyphenol Extracts Attenuated Depressive-Like Behaviors of High-Sucrose Diet Feeding Mice by Farnesoid X Receptor-Mediated Modulation of Bile Acid Circulation within the Liver-Gut-Brain Axis. Journal of agricultural and food chemistry. doi:10.1021/acs.jafc.4c07035PubMed 39475537DOI
Summary written 30 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error