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

June 30, 2022

A molecular view of inflammaging

Scientists this week at the Leibniz Institute on Aging–Fritz Lipmann Institute in Jena, Germany, are describing a comprehensive, multi-tissue look at gene networks that regulate inflammaging—the chronic age-related inflammation seen in mammals. They map the age-related inflammatory network to the increased opening of chromatin, the bundles of DNA and protein found in human cells, which enhances the expression and activation of innate immune system genes like interferon regulatory factors, inflammatory cytokines, and Stat1-mediated transcription factors. The researchers showed that these effects can be partially reversed in a tissue-specific manner through dietary changes, providing new anti-inflammaging therapeutic targets, they write. Cell Reports

Why so many IVF embryos fail to develop

One of the mysteries of modern reproductive medicine is why most IVF embryos “arrest” early, failing to progress beyond the 3- to 8-cell stage, never becoming a viable fetus. About 60 percent of IVF embryos fail to progress, which all too often forces women seeking pregnancy to undergo repeated expensive, uncomfortable, and emotionally taxing rounds of implantation. Now researchers at Shanghai University of Traditional Chinese Medicine and Southern University of Science and Technology in Shenzhen, China, say they have discovered the potential cause. Specific metabolic and epigenetic dysfunctions induce arrest by forcing embryos into senescence, where cell cycles halt and the activities of two critical proteins, MYC and p53, are knocked down—observations that could lead to new procedures to increase the success of IVF. PLOS Biology

Development of a human embryo, zygote to blastocyst. Tong Guoqing (CC-BY 4.0)

The impact of HIV infection on aging

Notwithstanding the modern medical miracle of antiretroviral therapy, which can effectively control HIV and has saved millions of lives in the last few decades, evidence suggests HIV induces earlier onset aging. Now a new study from UCLA following 102 people infected with HIV has shown specifically how the virus impacts human aging. Looking at measures of epigenetic age and telomere lengths prior to infection and three years post-infection, those 102 people showed significant aging when compared to control subjects who were not infected. “These longitudinal observations clearly demonstrate an early and substantial impact of HIV infection on the epigenetic aging process,” the researchers write. iScience

The smell of true friendship

While people generally refrain from sniffing each other’s butts, researchers at the Weizmann Institute of Science in Rehovot, Israel, have shown that we smell each other in our own way as a routine part of human bonding and that we prefer people who smell like we do. In a series of experiments, they recruited groups of same-sex friends and harvested their body odors by making them wash with unscented soap, wear a cotton tee shirt all night, and then freeze it in the morning. They measured the friend’s odors objectively with a device known as an electronic nose—and subjectively, by presenting the thawed shirts to a different group of people. Both experiments showed that shirts belonging to friends smelled more similar. They next recruited complete strangers, assessed their odors with an electronic nose, and then had them interact with others. The people who smelled more similar had more positive interactions, showing they could predict social bonding through body odor. Science Advances

Brain changes induced by menopause

Along with hot flashes, that nondescript feeling of “brain fog” is one of the most common symptoms of menopause women complain about. But what actually happens in the brain during menopause? According to the German Center for Neurodegenerative Diseases, it increases brain changes as measured by a biomarker known as white matter hyperintensities, which are tiny lesions visible on brain scans. White matter hyperintensities are more common with age and uncontrolled high blood pressure and have been associated with increased risk of stroke, Alzheimer’s disease, and cognitive decline. Looking at the brain MRIs of 3,410 people participating in the Rhineland Study (including 806 premenopausal and 1,167 postmenopausal women), the researchers showed that prior to menopause, women and men of similar ages did not differ in terms of white matter hyperintensities. But the burden of these hyperintensities was higher and accelerated faster in postmenopausal women compared to men the same age. They also found that postmenopausal women had more white matter hyperintensities than premenopausal women of similar age. Neurology

What once was brown may soon be gold

Doctors at Brigham and Women’s Hospital and Harvard Medical School in Boston are calling this week for “stool banking”—a new approach to address the alterations to the human gut microbiome in our modern, industrial world and the human diseases those alterations cause. Similar to the cryo-banking of your umbilical cord blood at birth for later use, the doctors envision banked and frozen stool samples from infants or children who are in optimal health could be used for fecal transplants to rejuvenate their own gut microbiomes later in life. Seems like a reasonable business opportunity to us. Trends in Molecular Medicine