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

November 18, 2021

Longevity-enhancing diets: Here’s what we now know

Anti-aging is a term too often left ill-defined when it’s used to sell products, especially when more often than not, there’s scant scientific evidence backing those sales claims. While some evidence exists for an actual anti-aging effect of drugs like metformin and rapamycin—as well as for calorie-restricted diets—there are currently no clinically validated antiaging interventions proven to work in humans. Hoping to help separate medical fact from marketing fiction, researchers at the University of Washington have made a comprehensive evaluation of several of the most popular anti-aging diets, including calorie restriction, intermittent fasting, ketogenic diets, time-restricted diets, protein restriction, and essential amino acid restriction. They advocate for reclaiming the term anti-aging and for using what we learn from clinical studies of these various diets to develop new biomarkers of aging and non-dietary interventions to increase longevity. Science

A rare glimpse at human embryonic development

A crucial if mysterious stage in early human development is known as “gastrulation,” which begins about 14 days after an egg is fertilized, continues for a week, and transforms a developing fetus from just a single layer of cells into a three-dimensional body. Almost everything we know about gastrulation, however, comes from studies on mice or other species—or from cell culture. But now a team at the University of Oxford in England and the Helmholtz Zentrum München–German Research Center for Environmental Health in Munich, Germany, have profiled mRNA transcripts for every cell in an entire gastrulating human embryo at 16–19 days post-fertilization. This allowed them to observe that red blood cells were present at this stage but not neurons—and more generally to verify that mouse gastrulation is actually a good model for humans. Nature

Infant microbiome appears to drive preterm birth complications

Preterm birth is a major driver of infant mortality, and premature babies are often prone to lifelong health problems. That creates a significant adverse health burden in low-income countries—and in the United States, where despite having one of the world’s highest incomes, 10 percent of all births are preterm. According to a new study from the University of Turku in Finland, preterm health complications may be linked to the microbiome. Fecal meconium transplanted from preterm infants into germ-free mice altered the rodents’ intestinal immune function, the researchers found, inducing inflammation, causing metabolic abnormalities, and leading to stunted growth. This suggests altering the microbiome in utero or shortly after birth could improve the long-term health of babies born too soon. Cell Reports Medicine

Psilocybin reduces alcohol craving in rats

The chemical psilocybin, found in psychedelic mushrooms, is believed to enhance the activity of a human receptor protein in the brain known as mGluR2, which is found in abundance in two brain regions known as the medial prefrontal cortex and the nucleus accumbens. These regions are avidly explored in alcohol addiction research because they mediate drug craving and relapse. Now researchers at the University of Heidelberg in Mannheim, Germany, have shown that rats missing this receptor in the prefrontal cortex exhibit excessive alcohol seeking, and they demonstrated that psilocybin was capable of restoring mGluR2 expression and reducing this behavior. They also identified a biomarker visible under a type of brain imaging known as FDG-PET, which could identify people who might respond to this sort of intervention. Science Advances

Smugglers beware: New AI can detect novel psychoactive substances

Researchers at the University of British Columbia have discovered a new approach to detecting new psychoactive substances (NPSs), which are designer chemicals meant to mimic the physiological effects of illegal drugs while eluding drug control laws—and often imported into western countries disguised as spice tins or bath salts. They created a deep-learning AI called DarkNPS that’s able to predict whether chemicals are new psychoactive substances based on a routine analysis with mass spectrometry. Nature Machine Intelligence

Do we sleep because of DNA repair?

We know that good sleeping habits are healthy and that poor sleep patterns are associated with bad health outcomes, but it’s still a mystery why we sleep in the first place. What purpose does it serve? Part of the answer, according to researchers at Bar-Ilan University in Ramat-Gan, Israel, may be that sleep facilitates DNA repair. They found DNA damage in neurons increases sleepiness through the action of a protein called Parp1, which senses the damage, promotes sleep, and enhances DNA repair in zebrafish and mice. Parp1’s relevance to regulating sleep may make it a tantalizing target for addressing sleep disturbances—and it may help illuminate links between sleep, aging, and neurodegenerative diseases. Molecular Cell

Treating diabetes with cookies?

Researchers at Peking University have developed an experimental cell-based therapy for diabetes that uses a special class of oddball biological molecules known as non-canonical amino acids to trigger engineered cells to produce insulin. These odd aminos are outside of the “canonical” 20 used by all forms of life on Earth, so they are typically not found in the food supply. But because they are small molecules, readily absorbed into the bloodstream through the digestive tract, they raise the possibility of a new oral insulin treatment instead of injection. The researchers successfully tested that idea, showing mice implanted with engineered cells and fed cookies containing these special trigger molecules achieved long-term glycemic control. Nature Chemical Biology

Telehealth proves effective in primary care

Since the start of the COVID-19 pandemic, telehealth use has skyrocketed (and so has telehealth fraud). But is it as good as receiving in-person care? Now a massive study by doctors at Kaiser Permanente confirms that remote doctoring is an effective way for people to access primary care. Examining data from more than 2.2 million primary care appointments (a mix of both telehealth and in-person office visits) scheduled by 1,131,722 Kaiser Permanente members in Northern California between 2016 and 2018, researchers found no difference in later health events (emergency department visits or hospitalizations) when comparing remote consultations to office visits. They also found that fewer drugs were prescribed following telehealth visits. JAMA