But if researchers at Cornell University’s College of Veterinary Medicine (CVM) are correct, there’s a powerful new way to slow or even halt that deterioration, and it lies inside extracellular vesicles. Those are tiny, membranous particles, ranging from 10 microns down to 20 nanometers, that exit cells and dwell in the spaces among them.
In their Journal of Biological Chemistry paper “Embryonic stem cell-derived extracellular vesicles delay cellular senescence by inhibiting oxidative stress,” lead author Shun Enomoto and colleagues explore how extracellular vesicles from embryonic stem cells can protect other cells from oxidative stress. That stress, which arises from an excess of free radicals and a dearth of anti-oxidants, causes cells to stop working and thus eventually die.
But extracellular vesicles from embryonic stem cells can prevent senescence, and for Enomoto, who is a doctoral student in biochemistry and molecular and cell biology, the process is “like harnessing the power of youth.”
Because scientists had already known that extracellular vesicles could help embryonic stem cells continue offering their benefits, the researchers investigated whether extracellular vesicles could regenerate wounded tissue. For Enomoto, therefore, “The question we were next interested in was whether these extracellular vesicles could not only help cells regenerate, but also delay or stop their aging.”
After extracting extracellular vesicles from embryonic stem cells procured from mice, Enomoto and colleagues added them to ordinary cells (which by definition are differentiated into various forms and functions as nerve, muscle, skin, and other cells – unlike stem cells, which are undifferentiated and thus still have the potential to become any type of cell). Amazingly, the cells exposed to the extracellular vesicles completely halted senescence: no more deterioration.
“It was an amazing thing to watch these treated cells just continue to grow long after the untreated ones had stopped,” said Marc Antonyak, associate research professor in the Department of Molecular Medicine, who collaborated with Enomoto and Richard Cerione, a Distinguished Professor of Arts and Science in Chemistry.
Further experiments revealed that the extracellular vesicles stopped senescence by using the extracellular matrix protein fibronectin, which coats their surfaces and then causes a release of enzymes that block the effects of oxidative stress which unleash senescence.
New Atlas has previously explored the use of “young blood” extracellular vesicles that help old mice fight aging, and the role of exercise in stimulating extracellular vesicles to trigger neurogenesis (the creation of neurons) and delay or prevent neurological decay. The Cornell experiments are the latest development in anti-aging breakthroughs.
“Our ultimate goal is to test these vesicles directly in mice to see if they affect the organism’s aging,” says Enomoto. If these tests succeed, Enomoto and his colleagues will test human cells, although any human stem cells they use would be regular adult cells they genetically reprogram to revert an embryonic state.
The implications of the breakthrough are enormous – not only for lifespan, but for healthspan, says Antonyak. “This work could have a lot of important applications for human health.”
Source: Cornell University/New Atlas.
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