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

May 12, 2022

The Tabula Sapiens: A massive new human cell atlas

Gene expression got a whole lot more interesting today as a consortium of researchers going by the baroque moniker “Tabula Sapiens Consortium” just published four studies analyzing gene expression across the entire human body. The consortium analyzed RNA transcripts in some 483,152 cells falling into 400 separate cell type categories taken from 24 different tissues and organs across the bodies of 68 men and women from a range of ethnicities and medical backgrounds. The results have allowed researchers to tease apart genetic activity across the body, showing how some gene expression is highly tissue-specific while some is universal. It has allowed the researchers to identify rare cell types and to finger cells whose aberrant or normal gene expression play key roles in human health or disease. Science

Primordial soup, RNA, and the origins of life

Almost 100 years ago, a young Soviet biochemist named Aleksandr Oparin proposed that life on Earth emerged “abiogenically,” from a chemical soup of molecules that somehow began to replicate. Many scientists ever since have chased the dream of finding the missing links between a primitive, lifeless planet and the earliest thriving exosystems of blue-green algae that gave rise to stromatolites, the first fossilized evidence of terrestrial life some 3.9 billion years ago. One leading theory is the so-called RNA world hypothesis, which holds that modern DNA and protein-based life evolved from self-replicating RNA molecules—but nobody has ever been able to prove it. Now chemists at Ludwig Maximilian University in Munich, Germany, have shown that the answer may lie in strange, ancient RNA bases, which are found today inside some of the molecular machines of biology, such as ribosomes. They are suggesting that these “non-canonical” RNAs could be the missing link that led to a hybrid RNA-protein world and eventually to all of modern life. The title alone of this paper makes it worth clicking on! Nature

Bad news for espresso drinkers?

A population-based study of 21,083 male and female coffee drinkers in Northern Norway, all 40 years old or older, has found an association between espresso consumption and serum total cholesterol. Taken from self-assessments collected in the Tromsø Study in Northern Norway, the study compared espresso drinkers to people who drank coffee made in plunger carafes versus filtered pour-over machines versus people who drink instant coffee. The most important finding, according to researchers at the Arctic University of Norway who conducted the study, was that espresso consumption was significantly associated with increased serum total cholesterol—though they write that further research on the association between espresso and serum cholesterol is needed to inform actual recommendations regarding coffee consumption. BMJ Open Heart

Young CFS infusions boost mouse memory

Infusing cerebrospinal fluid (CSF) from young mice directly into the brains of older mice improved their memory function, according to researchers at Stanford University. The researchers tied the effect to a type of brain cell called oligodendrocytes, which produce the myelin sheath insulating the axons of brain neurons. Young CSF enhances the proliferation and differentiation of oligodendrocyte cell precursors, and the researchers identified a protein called fibroblast growth factor 17 (Fgf17) as the “active ingredient” in the young CFS. This suggests that Fgf17 could be a new target for restoring oligodendrocyte function and improving memory in aging brains—and hopefully one day heal human heads! Nature

Could ibuprofen make back problems worse?

Lower back pain is the most common form of chronic pain, inflicting a huge cost on society and a much more personal, groaning burden of misery on countless people. Now a surprising new study from McGill University in Montreal suggests that the very thing people reach for when they suffer lower back spasms could actually make outcomes worse: over-the-counter NSAID anti-inflammatory drugs like ibuprofen. Following gene-expression transcriptional changes in 98 people with acute low back pain for three months, the researchers found that upregulated gene responses in a type of inflammatory immune cell known as a neutrophil protected people against graduating to chronic pain. But those same neutrophil responses are inhibited by NSAID drugs, and analyzing data from the UK Biobank, they found NSAID usage put people with acute lower back pain at 1.76-fold greater risk of developing chronic back pain. Taking these drugs, they write, inhibits inflammation and could be counterproductive to healing and increases the odds of chronic pain by interfering with natural recovery. Science Translational Medicine