For years, the aging process has confounded scientists and held a tight grip on the mysteries of life’s progression. Everything from youth cocktails to young blood transfusions has been experimented with to revert the aging process.
Another revelation hints at a glimmer of hope.
A team of Chinese scientists has identified a group of cells called CHIT1 in the spinal cord, which is linked to the process of aging.
While the scientists are still in the early stages of understanding the practical applications of this discovery, they believe that taking a daily dose of vitamin C might help slow down aging.
CHIT1: A marker for treating spinal cord aging issues?
As an antioxidant, vitamin C is often considered to have potential anti-aging properties. Antioxidants help protect the skin from damage caused by free radicals, which are unstable molecules that can accelerate the aging process and contribute to issues like wrinkles, fine lines, and skin sagging.
The prospect of harnessing the power of vitamin C to slow down aging has certainly set the scientific community abuzz over the last decade.
Aging also has a significant impact on spinal cord-related problems, but we don’t fully understand how it works. To unravel the tapestry of time, the scientists conducted their study in an animal model and found that as the spinal cord ages, two important things happen.
One, the motor neurons that help in our movement get rusty and old, and the immune cells in the spinal cord get overactive.
“These distinct cell clusters must have a specific life purpose. Our further investigation revealed that they secrete a ‘toxic’ protein that contributes to accelerating the aging of motor neurons,” Liu Guanghui, first author of the study, told the South China Morning Post.
The second thing that happens is that the quantity of a substance called CHIT1 goes up in old spinal cords. These cells then gather around motor neurons and make them age faster. However, researchers found a way to counteract this.
Their study says that ascorbic acid, which is known to slow down aging, can counteract the effects of CHIT1 and help keep motor neurons healthy. Vitamin C is also known as L-ascorbic acid.
Anti-aging breakthrough via vitamin C
The researchers also tested the effects of vitamin C on 10 older cynomolgus monkeys in the span of three years. They divided them into two groups. One group got a daily dose of vitamin C, while the other group was the control group.
The researchers found that the monkeys who received vitamin C showed a “significant” improvement in the signs of aging in their motor neurons. This suggests that taking oral vitamin C supplements might be helpful for older individuals.
Although the researchers made their discoveries by studying animals, they found higher levels of CHIT1 in the fluid around the human brain and in the blood of older individuals.
The study was published in the peer-reviewed journal Nature on October 31, 2023.
Study abstract:
Aging is a critical factor in spinal cord-associated disorders1, yet aging-specific mechanisms underlying this relationship remain poorly understood. To address this knowledge gap, we combined single-nucleus RNA sequencing with behavioral and neurophysiological analysis in non-human primates (NHPs). We identified motor neuron senescence and neuroinflammation with microglial hyperactivation as intertwined hallmarks of spinal cord aging. As an underlying mechanism, we identified a previously unreported neurotoxic microglial state demarcated by elevated expression of CHIT1 (a secreted mammalian chitinase) specific to the aged spinal cords in NHP and human biopsies. In the aged spinal cord, CHIT1-positive microglia preferentially localize around motor neurons (MNs), and they are capable of triggering senescence, partly by activating SMAD signaling. We further validated the driving role of secreted CHIT1 on MN senescence by multi-modal experiments both in vivo, utilizing the NHP spinal cord as a model and in vitro, employing a sophisticated human MN-and-microenvironment interplay modeling system. Moreover, we demonstrated that ascorbic acid, a geroprotective compound, counteracted the pro-senescent effect of CHIT1 and mitigated motor neuron senescence in aged monkeys. Our findings provide the first single-cell resolution cellular and molecular landscape of the aged primate spinal cord and identify a new biomarker and intervention target for spinal cord degeneration.
This content was originally published here.
