Aging Neurons: New Molecules Protect Against Neurodegeneration | C. elegans Study
- The human brain, with its approximately 90 billion neurons, is vastly more complex than the nervous system of the nematode Caenorhabditis elegans, which consists of just 302 neurons.
- Researchers at the University of Cologne, led by Professor Dr.
- The researchers observed significant differences in cellular age even in young worms.
The human brain, with its approximately 90 billion neurons, is vastly more complex than the nervous system of the nematode Caenorhabditis elegans, which consists of just 302 neurons. Yet, neurons in the roundworm perform similar functions to those in the human nervous system. This makes C. Elegans a valuable model organism for studying how the brain ages and what factors contribute to neurodegeneration.
Researchers at the University of Cologne, led by Professor Dr. Björn Schumacher, have developed a novel “aging clock” that can predict the biological age of individual neurons in C. Elegans based on changes in gene expression. This allowed them to track the aging process of each nerve cell throughout the organism’s lifespan. The study, titled “Aging clocks delineate neuron types vulnerable or resilient to neurodegeneration and identify neuroprotective interventions,” was published in in Nature Aging.
Premature Neuronal Aging
The researchers observed significant differences in cellular age even in young worms. Some neurons appeared considerably “older” than the animals themselves. Dr. Christian Gallrein, a neuroscientist now at the Leibniz Institute for Age Research – Fritz Lipmann Institute in Jena, investigated what happened to these prematurely aged nerve cells in young adult worms. These cells rapidly showed massive degeneration, with their nerve extensions retracting within a short period.
The team identified the production of proteins as a key driver of neuronal aging. Rapidly aging nerve cells exhibited particularly active protein biosynthesis. Pharmacologically inhibiting this process helped preserve these quickly aging neurons. Given the similarities in neuronal aging between C. Elegans and the human brain, the researchers developed an artificial intelligence-assisted approach. Using machine learning, they classified therapeutic substances based on whether they could accelerate or delay the neuronal aging process.
Protective and Harmful Substances
This analysis revealed several small molecules, including syringic acid – a plant-derived natural compound found in blueberries and blue grapes – and vanoxerine, a dopamine reuptake inhibitor, that protect nerve cells from the aging process and help maintain the nervous system’s integrity with age. Conversely, substances like WAY-100635, a serotonin-5-HT1A receptor antagonist, and resveratrol were identified as potentially accelerating aging and neurodegeneration, potentially acting as neurotoxins.
“Our work has, for the first time, shown the differences in the aging process of individual nerve cells,” said Professor Schumacher. “This opens up entirely new insights into why some neurons age early. We now also have a new approach, using machine learning, to quickly identify therapeutic substances that could eventually enable the development of novel treatments to preserve brain function or prevent neurodegenerative diseases.”
Research published in by Nagoya University researchers adds another layer to this understanding. Their study, published in the journal Proceedings of the National Academy of Sciences, found that aging-related decline in brain function is caused by excessive activation of certain neurons over time, rather than a decrease in neuronal activity. This challenges the long-held assumption that declining brain function is primarily due to neuronal inactivity.
The Nagoya University team used C. Elegans and its ability to learn through association – a behavior called thermotaxis – to investigate this phenomenon. Associate Professor Kentaro Noma explained that C. Elegans shares many genes and mechanisms with humans, suggesting that the findings may be applicable to human brain aging. The study suggests that interventions aimed at reducing neuronal hyperactivation, such as dietary changes, could potentially mitigate age-related cognitive decline.
Further supporting the utility of C. Elegans as a model for neurodegenerative disease, a review published in in Frontiers in Cellular Neuroscience highlights the organism’s advantages: its simplicity, rapid growth, short life cycle, transparency, and relatively simple genetics. Researchers have successfully modeled neurodegenerative diseases in C. Elegans by expressing proteins linked to neurodegenerative aggregates, such as amyloid-β peptide, tau protein, and α-synuclein. The availability of RNA interference libraries and the ability to create new transgenic strains provide a powerful toolkit for studying the signaling pathways involved in these diseases.
A separate study, also published in , reported by Medical Xpress, utilized the aging clock developed by the University of Cologne team to identify molecules that protect against age-related neurodegeneration. This reinforces the idea that understanding the specific vulnerabilities of different neuron types is crucial for developing targeted interventions.
The convergence of these findings underscores the potential of C. Elegans as a powerful tool for unraveling the complexities of brain aging and neurodegenerative diseases. While the research is preliminary, it offers promising avenues for identifying therapeutic targets and developing strategies to protect against age-related cognitive decline.