Gut bacteria and the liver attach glycine to a tryptophan metabolite called IAA, a step normally thought to shut off its activity. A Penn State study found the resulting molecule, IAA-glycine, still switches on the aryl hydrocarbon receptor in human samples, based on the study's abstract and press coverage since the full paper was not obtained.
A cross-sectional preprint study of 61 adolescent girls in treatment for anorexia nervosa or atypical anorexia nervosa found gut microbiome differences from healthy peers that did not fully resolve even near full treatment goal weight. The findings are preliminary, not yet peer-reviewed, and do not show cause and effect.
A flavonoid extract from the leaves of Cyclocarya paliurus, a Chinese folk-medicine tree, protected dopamine neurons and improved motor function in mice with chemically induced Parkinson's disease, while reshaping gut bacteria and tryptophan metabolism. The gut-bacteria link is correlational, and the work is mouse-only.
A cohort study of Chinese adults links more moderate-to-vigorous activity to lower fatty liver risk and more sitting to higher risk. In a 245-person subset, Proteus gut bacteria and blood L-valine tracked with both inactivity and disease, though the evidence is associational.
Babies given formula within 24 hours of birth had about 3.6 times the odds of an egg allergy by age one in a Perth cohort of 563 high-risk infants. The link is observational, rests on 18 cases, and the colostrum and gut microbiome explanation was not measured.
A systematic review of seven patient-cohort studies links two rare Parkinson-like diseases, MSA and PSP, to fewer short-chain fatty acid producing gut bacteria and signs of a leakier gut barrier. The evidence is associational, and the studies contradict each other on key bacteria.
Pooling 18 randomized trials, researchers found that gut-targeted treatments, mostly probiotics and diets, were linked to less osteoarthritis pain and better function. A cartilage marker did not budge, and certainty ranged from high to very low.
In a 1,404-patient randomized trial, two seven-day vonoprazan-based regimens without bismuth matched the cure rate of the standard 14-day H. pylori treatment - though three other shortened regimens fell short, showing that drug pairing, not just duration, decides success.
A new study finds that pemafibrate, a lipid drug already prescribed for high triglycerides, lowers the hormone leptin and boosts gut bacteria linked to liver health in mice and in a 192-patient MASLD cohort — offering the first detailed mechanism for benefits doctors were already seeing.
A new Cell Reports study finds that Lactobacillus plantarum, a common skin bacterium, is depleted in psoriatic lesions across a 94-person human cohort. Its metabolite indole-3-lactic acid (ILA) restores a circadian clock protein, Bmal1, that activates Sirt3 to suppress ferroptosis, a form of cell death — and mouse experiments show removing either the metabolite or the clock gene erases the protective effect.
