Heart disease risk tied to certain molecules made by gut microbes

Bloodstream levels of nine specific metabolites produced by gut microbes are statistically associated with the risk of developing coronary heart disease. These associations persist after accounting for factors such as age, family history, and diet, though some differences appear by race or age. The identified metabolites may serve as potential biomarkers or therapeutic targets for coronary heart disease.
In a study involving data from thousands of people, the risk of a new coronary heart disease diagnosis was statistically associated with bloodstream levels of nine specific molecules that are produced by gut microbes.
The human digestive tract naturally contains a large population of microbes. Different people have different proportions of different species of gut microbes, which produce different molecules during their normal, metabolic chemical reactions.

These metabolites can enter the bloodstream and exert a broad range of impacts, good and bad, on human health. Some gut microbe metabolites may be linked with a person's risk of coronary heart disease—the world's leading cause of death.

Using data from nearly 2,000 of the participants, researchers discovered several gut microbe metabolites associated with the risk of developing coronary heart disease. Then, they used the rest of the data to validate and refine these links—including external and quantitative validations, and accounting for many other factors known to be associated with risk of coronary heart disease, such as age, family health history, and diet.

The final analysis revealed nine specific gut microbe metabolites in the bloodstream that were associated with a higher or lower chance of developing coronary heart disease. These links remained consistent across some participants when stratified by lifestyle or family history. However, some differences in links between specific metabolites and heart disease risk were found when individuals were stratified by race or age.
This study underscores the link between gut microbes and heart health. On the basis of the findings, the researchers call for follow-up research into the nine metabolites they identified to determine whether they represent potentially promising avenues for development of novel ways to treat or prevent coronary heart disease.

Zheng Y, et al. Circulating gut microbial metabolites and risk of coronary heart disease: A prospective multi-stage metabolomics study.PLOS Medicine (2026). DOI: 10.1371/journal.pmed.1004750

Engineered bacteria deliver cancer drug directly inside tumors in mice

Engineered Escherichia coli Nissle 1917 (EcN) can be modified to produce and deliver the anticancer drug Romidepsin (FK228) directly within tumors in mice. The bacteria selectively colonize tumors and release the drug in situ, resulting in targeted tumor therapy. This approach demonstrates potential for bacteria-assisted, tumor-targeted delivery of anticancer agents.

Ma C, et al. Engineered romidepsin biosynthetic pathways in Escherichia coli Nissle 1917 improve the efficacy of bacteria-mediated cancer therapy, PLOS Biology (2026). DOI: 10.1371/journal.pbio.3003657

Closing your eyes might not help you hear better after all

Most people will close their eyes when trying to concentrate on a faint sound. Many of us have been told that keeping our eyes closed helps us hear better—that it frees up our brains' processing abilities and increases our auditory sensitivity. However, that strategy may sometimes backfire, particularly in environments with a lot of loud background noise.
Closing the eyes in noisy environments reduces the ability to detect faint sounds, contrary to common belief. Visual input, especially dynamic videos matching the sound, enhances auditory sensitivity. Eye closure leads to neural filtering that can suppress both noise and target sounds, while visual engagement helps the brain separate signals from background noise.
In The Journal of the Acoustical Society of America, researchers tested whether a person closing their eyes can really hear better in noisy environments.

To test this, volunteers listened to a collection of sounds through headphones amid background noise. Then, the volunteers adjusted the volume of the sounds until they could barely make them out over the background noise.

This test was conducted first with eyes closed, then with eyes open but looking at only a blank screen, then looking at a still picture corresponding to the sound, and finally, looking at a video matching up with the sound they were trying to hear.
To their surprise, the researchers found that, contrary to popular belief, closing one's eyes actually impairs the ability to detect these sounds! Conversely, seeing a dynamic video corresponding to the sound significantly improves hearing sensitivity.
To find an explanation for this result, the researchers attached electroencephalography (EEG) devices to the participants to monitor their brain activity. They determined that closing the eyes puts a participant's brain in a state of neural criticality, which more aggressively filters noises and quiet sounds, including the target sounds those participants were trying to detect.

In a noisy soundscape, the brain needs to actively separate the signal from the background, The researchers found that the internal focus promoted by eye closure actually works against you in this context, leading to over-filtering, whereas visual engagement helps anchor the auditory system to the external world.
The authors emphasize that this result is unique to noisy environments. With a calmer background, the conventional strategy of keeping their eyes closed likely does help people detect faint sounds. But because so much of our lives are spent surrounded by noise, it might be better to face the world with eyes wide open, say the researchers.

Visual engagement modulates cortical criticality and auditory target detection thresholds in noisy soundscapes, The Journal of the Acoustical Society of America (2026). DOI: 10.1121/10.0042380