Mulberry Extract Eases Insomnia by Rebalancing Gut Bacteria in Mice

If you have ever noticed your gut acting up during a stretch of bad sleep, or wondered whether fixing one problem might help the other, a new mouse study offers a mechanistic clue rather than an answer. Researchers in China found that an extract of anthocyanins (the pigments that give berries their deep red and purple color) from mulberry fruit eased insomnia-like symptoms in mice, and traced part of that effect back to changes in the gut microbiome (the community of bacteria living in the intestines). The work, published in the Journal of Agriculture and Food Research, adds to a growing pile of evidence linking sleep and gut bacteria, though the findings come from mice, not people.

KEY TAKEAWAYS

• In mice made insomniac with a serotonin-depleting drug, mulberry fruit anthocyanin extract (MFE) restored normal activity levels, brain chemistry, and body weight.
• MFE lowered the Firmicutes/Bacteroidetes ratio (a common marker of gut bacterial balance) and enriched beneficial bacteria including Akkermansia and Muribaculaceae.
• The extract was linked to calmer inflammatory signaling (the TNF and IL-17 pathways) and a serotonin-related brain pathway, alongside lower levels of three inflammatory genes in the hippocampus.
• This is one animal study: whether the gut bacteria shift actually drives the improvement, or is a side effect of the anthocyanins acting directly on the brain, was not tested apart from each other.

Mulberry Anthocyanin Extract Eased Insomnia-Like Behavior in Mice

Researchers from the Guangdong Academy of Agricultural Sciences found that a mulberry fruit anthocyanin extract (MFE), dosed daily for 14 days, reversed several signs of insomnia in mice, according to a study published in the Journal of Agriculture and Food Research. The extract is dominated by cyanidin-3-glucoside (C3G), a specific anthocyanin compound that made up roughly 250 milligrams of every gram of the extract. To create the insomnia model, the team injected mice with para-chlorophenylalanine (PCPA), a compound that blocks the body's synthesis of serotonin (a brain chemical involved in mood and sleep regulation) and reliably produces disrupted circadian rhythm, daytime hyperactivity, and reduced food intake in rodents. Mice that received MFE afterward showed improved locomotor activity and less of the body weight loss that typically accompanies the insomnia model, changes the researchers measured against untreated insomniac mice and against a separate group given Anshen Bunao Oral Liquid, a marketed traditional Chinese medicine sleep aid used here as a benchmark treatment.

Why This Matters for Anyone Managing Sleep or Gut Symptoms

Sleep loss and gut symptoms often show up together, and this study is part of a broader research push trying to explain why. The researchers found that MFE restored the balance between GABA (a calming brain chemical) and glutamate (an excitatory one) and raised serotonin levels in brain tissue, changes consistent with reduced neurological hyperarousal. That matters to readers who suspect their own sleep problems, anxiety, or digestive symptoms trace back to the same underlying axis: a large and separate body of human and mouse research on the gut-brain axis and insomnia has independently linked gut bacterial imbalance to disrupted sleep, including one recent mouse study showing that transplanting gut microbes from insomnia patients into germ-free mice produced insomnia-like behavior. None of this establishes that eating mulberries or anthocyanin supplements will fix human insomnia, but it strengthens the case that the gut and the sleep-regulating brain circuits are talking to each other.

How the Study Was Designed

The team worked with 48 male mice split evenly into four groups of 12: untreated controls, an insomnia-model group, a group treated with the standard sleep-aid comparator, and the MFE group. After confirming the insomnia model had taken hold (via the behavioral changes described above), mice received their assigned treatment by mouth for 14 consecutive days. The researchers then measured brain and gut outcomes using several methods at once: enzyme-linked immunosorbent assays (ELISA) for neurotransmitters and inflammatory markers in brain and blood tissue, full-length 16S rRNA gene sequencing of gut bacteria from intestinal contents, untargeted serum metabolomics (a broad scan of small molecules circulating in blood) via mass spectrometry, and RT-qPCR (a technique that measures how active specific genes are) to confirm which biological pathways were involved. Combining behavioral, microbial, chemical, and genetic measurements in the same animals is what let the researchers connect a change in gut bacteria to a change in brain chemistry within the same study, rather than relying on a single type of measurement.

What the Gut Bacteria Findings Actually Showed

On the microbiome side, MFE-treated mice showed a lower Firmicutes/Bacteroidetes (F/B) ratio, a widely used if imperfect marker of gut bacterial community balance that tends to shift with diet and metabolic health, along with enrichment of two specific bacterial groups: Akkermansia, a genus separately linked in other research to improved gut barrier function and metabolic health, and Muribaculaceae, a family of bacteria common in the mouse gut. Serum metabolomics also picked up elevated levels of several circulating metabolites, including amino acid derivatives and organic acids, changes the researchers interpreted as downstream signatures of the microbial shift. On the inflammation side, MFE lowered the hippocampal (a brain region involved in memory and stress response) activity of three pro-inflammatory genes, PTGS2, IL-6, and IL-1β, and network pharmacology analysis (a computational method for predicting which biological pathways a compound likely affects) pointed to the TNF and IL-17 inflammatory signaling pathways and a serotonin-related brain signaling pathway as the most likely mechanistic links, a prediction the RT-qPCR results were used to help confirm.

What Remains Unproven

This is a single animal study, not a human trial, and the authors themselves flag the central open question directly in their own paper: they describe the gut-brain connection here as "a mechanistic hypothesis that warrants further causal validation." In plain terms, the study shows that MFE changed the gut microbiome and the brain chemistry at the same time, but it does not prove the microbiome change is what caused the improvement in insomnia symptoms. Anthocyanins are known to act directly on the brain and on inflammation independent of the gut, so the two effects have not been separated from each other. There is also no comparison group that had its microbiome altered without receiving MFE, the kind of experiment (such as fecal transplant or antibiotic depletion) that would be needed to test causation directly. A separate line of research on anthocyanins broadly has found they can shift the Firmicutes/Bacteroidetes ratio and related gut health markers across other contexts, which is consistent with what was seen here but does not resolve the causality question either.

What Comes Next

The researchers frame this work as a rationale for developing MFE as a "functional food" for sleep health, but that is a research direction, not a near-term product recommendation. The logical next steps, based on how this kind of causal gap is typically closed in gut-brain research, would be experiments that isolate the microbiome's role directly, such as giving MFE to germ-free mice or mice with depleted gut bacteria, or transferring the MFE-shifted microbiome into untreated insomniac mice to see if the behavioral improvement transfers with it. Human trials are a further step beyond that, and none have been conducted on this specific extract. No timeline for either was given in the study.

Common Questions

Does this mean mulberries or mulberry supplements will help me sleep? No. This study used a concentrated, standardized extract dosed daily in mice with a chemically induced insomnia model; it does not establish that eating mulberries, or taking an over-the-counter anthocyanin supplement, has any effect on human sleep.

What is the gut-brain axis? It is the two-way signaling network connecting the gut microbiome to the brain, involving nerve pathways (like the vagus nerve), immune signaling, and microbial metabolites that can cross into circulation. Researchers increasingly study it in connection with mood, cognition, and now sleep.

What is Akkermansia and why did it come up here? Akkermansia is a genus of gut bacteria that has been separately linked, mostly in mouse studies, to a healthier gut lining and better metabolic markers. Its enrichment here is a correlation the researchers noted, not a benefit that was independently tested in this study.

Is this the same as taking a probiotic for sleep? No. MFE is a plant polyphenol extract, not a live bacterial supplement. The study observed that it changed which bacteria were present in the gut; it did not test whether adding those bacteria directly, as a probiotic would, produces the same effect.

References

1. Anyi Liu, Qian Li, Xinyi Zhong, et al. (2026). Mulberry fruit anthocyanin extract modulates insomnia-related behavioral and neurochemical alterations via the gut–brain axis: A multi-omics and network pharmacology study. Journal of Agriculture and Food Research. https://doi.org/10.1016/j.jafr.2026.103261
2. Xuchi Chen, Taosheng Liu, Jian Dai, Shuai Wang, Chang Liu, Juan Huang (2026). Interplay between gut microbiota and insomnia: latest research advances based on the gut-brain axis. Sleep Science and Practice. https://doi.org/10.1186/s41606-026-00187-6
3. Z. Wang, Y. Han, L. Lu (2026). Gut microbiota regulate insomnia-like behaviors via gut-brain metabolic axis. Sleep Medicine. https://doi.org/10.1016/j.sleep.2025.107332
4. Ezinne Aja, Amber Zeng, Weston Gray, Kaden Connelley, Anil Chaganti, Jonathan P. Jacobs (2025). Health Effects and Therapeutic Potential of the Gut Microbe Akkermansia muciniphila. Nutrients. https://doi.org/10.3390/nu17030562
5. Payal Kapoor, Apoorv Tiwari, Saloni Sharma, et al. (2023). Effect of anthocyanins on gut health markers, Firmicutes-Bacteroidetes ratio and short-chain fatty acids: a systematic review via meta-analysis. Scientific Reports. https://doi.org/10.1038/s41598-023-28764-0