Dispatches

The week’s most astounding developments from the neobiological frontier.

June 16, 2022

Exercise releases blood metabolite and helps control weight

The blood of running humans and sprinting racehorses is enriched for a small molecular metabolite known as N-lactoyl-phenylalanine (Lac-Phe), according to researchers at Stanford University and Baylor College of Medicine. Controlling it may be a key to future weight-loss therapies. Lac-Phe helps explain biochemically how exercise confers protection against obesity, diabetes, and cardiovascular diseases, the researchers say, and administering it to overeating fat mice caused them to eat less without affecting their movement or energy levels. Fat mice constantly given Lac-Phe lost body weight and improved their glucose levels. Disrupting Lac-Phe biosynthesis in skinny mice, on the other hand, caused them to increase food intake and grow fat. While there is no “exercise pill” immediately in the offing, this work could lead to new therapeutic ways of maximizing the benefits of physical activity for human health, the researchers write. Nature

Genetics of taste linked to dietary choice

At the annual meeting of the American Society for Nutrition this week, researchers from Tufts University in Boston are presenting preliminary results of research involving 6,230 people from the Framingham Heart Study relating SNP genetic variants of taste perception to dietary food choice and cardiometabolic risk factors such as waist circumference, blood pressure, and cholesterol levels. Comparing the diets to genomic information revealed the broad influence of sweet, bitter, and umami-related genes on food intake. “Understanding the individual-level drivers of food choices is critical for designing personalized nutrition guidance,” the authors write. Presentation abstract

How stress affects aging immune cells

The aging of our immune system as we grow old impacts our health in many ways, and immune aging can be made much worse by acute or chronic stress. Wanting to gauge the age-related molecular impacts of social stress—things like traumatic life events, chronic pressure, or discrimination—researchers at the University of Southern California analyzed immune cells from a nationwide sample of 5,744 U.S. adults over age 50. They showed how chronic stress and everyday discrimination impacts CD4+ T cells and how major life traumas and lifetime discrimination impacts CD8+ T cells. The work identifies “important points of intervention that may be useful in addressing inequalities in aging,” the authors write. PNAS

Atlas of death

This week, a new open-access atlas of mortality estimates appeared that reveals comprehensive metrics on 1,803 specific diseases and disorders and how they impact lives, life expectancies, and deaths. Researchers at Aarhus University, Denmark, created the atlas from a population-based study involving 7,378,598 people living in the country from 2000–2018, and they published it alongside a front-end visualization tool. It will allow “more fine-grained analysis of the link between a range of disorders and key mortality estimates,” they write. PLOS Medicine

New open-source device for detecting hearing loss

Researchers at the University of Washington in Seattle have developed an inexpensive, open-source “tympanometry” device that measures air pressure and ear drum mobility in the middle ear—one of a battery of tests used to diagnose hearing loss. Traditional tympanometry equipment is expensive, placing it out of reach for many of the world’s children, but the new device is designed to plug into a smartphone. The researchers validated their prototype against traditional equipment in a group of 50 children at an audiology clinic, and they say that given the wide accessibility of budget phones in low-income settings, their new device could expand affordable screening and help diagnose middle ear disorders earlier when they are more treatable. Communications Medicine

The genetics of grooviness

Is your ability to keep a beat to the rhythm genetic? That’s the implication of a new genome-wide association study from Vanderbilt University Medical Center in Nashville, Tennessee, which looked at DNA from 606,825 Europeans. The study identified 69 genomic loci that appeared to be associated with typical versus atypical beat synchronization, and it validated those associations with a subset of people by asking, simply, Can you clap in time with a musical beat? The work suggests that grooviness is a highly polygenetic trait, emerging from the overlapping tempo of many different genes. Based on their genomic markers of beat synchronization, the researchers could pick the likely musicians out of the crowd, and they found that people who have enhanced capacity for rhythm tended to be deep breathers, fast walkers, heavy smokers, and night owls with strong handshakes and tinnitus ringing in their ears. Right on. Nature Human Behavior