Body & Brain

The health benefits of wheat and olive oil, plus Down syndrome dementia, a heartbreaking gene and more in this week’s news

Unusual gene increases vessel tear risk People with an uncommon duplication of a gene have a 12-fold increase in the risk of having a torn aorta, a lethal leak in the crucial artery that carries blood out of the heart. Researchers at the Baylor College of Medicine and the University of Texas in Houston found the duplication on chromosome 16 in 8 of 765 patients who had an aortic aneurysm or tear but in only 4 of more than 4,500 people with intact aortas. Although the gene duplication is unusual, it confers a clear risk to those carrying it, the scientists report in the June PLoS Genetics . — Nathan Seppa

Olive oil versus stroke People who consume olive oil copiously appear less vulnerable to stroke than those who avoid it, medical records from 7,600 people in France show. Scientists used questionnaire responses to classify people as those who never use olive oil, those who use it either to cook or as a dressing for bread or salad or those who use it for all of those purposes. They then tallied up the number of strokes among the study participants over a five-year period. After adjusting for differences among the groups, the most frequent users of olive oil were 41 percent less likely to have had a stroke than the abstainers, a French research team reported online June 15 in Neurology. Nathan Seppa

Human nose cells help mice remember Stem cells taken from human noses can help repair damaged mouse brains. In people, stem cells continuously divide and replenish odor-sensing nerve cells in the nasal cavity. When researchers implanted these human cells into mice with brain injuries, the cells traveled to the site of damage and settled in, dividing and producing nerve cells, French researchers report online June 13 in the Journal of Clinical Investigation . What’s more, brain-damaged mice who received donor human cells performed better on learning and memory tests. These nose stem cells may also be able to repair brain injuries in humans and would be free from the ethical considerations that plague embryonic stem cells, the authors write. — Laura Sanders

Dementia in Down syndrome As people with Down syndrome get older, ominous clumps and strands of proteins build up in brain regions important for memory, reasoning and emotions, a brain-scan study finds. The results help explain why many people with Down syndrome develop an Alzheimer’s-like dementia. UCLA researchers looked for protein plaques and tangles — two hallmarks of Alzheimer’s disease — in the brains of 19 people with Down syndrome and 10 people with Alzheimer’s disease. Although the people with Down syndrome were younger and showed no signs of dementia, they had higher levels of plaques and tangles than the people with Alzheimer’s, researchers report in the June Archives of Neurology . — Laura Sanders

Wheat extract fights obesity and more Eating meals enriched with arabinoxylan — a constituent of dietary fiber — improves weight and blood sugar control in mice, Belgian scientists report June 9 in PLoS ONE . Studies had shown that high-fat diets diminish populations of beneficial gut bacteria, contributing to weight gain. For their new study, the scientists added arabinoxylan from wheat to the high-fat fare they fed some adult mice. After four weeks, these animals had higher concentrations of good gut germs than did mice getting just the high-fat fare. They also developed less body fat, had better blood sugar control and showed fewer signs of inflammation, all results of the arabinoxylan supplementation, the authors conclude.  — Janet Raloff

High-fat diet may injure brain In animals, diets high in fat can injure brain cells responsible for controlling body weight. In a new study, researchers fed rats and mice various diets for several days to many months and then measured biochemical changes in the animals’ brains. High-fat diets induced signs of both inflammation and wound healing, Joshua Thaler of the University of Washington in Seattle reported June 7 at the Endocrine Society meeting in Boston. These changes occurred in the hypothalamus, where among other things, the scientists witnessed a loss of cells crucial to weight regulation. Thaler said these findings “offer a new explanation for why sustained weight loss is so difficult for most obese individuals.” — Janet Raloff

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