Adults Can Potentially Generate New Brain Cells, According to Recent Research Shedding Light on a Long-Standing Controversy in Neuroscience
In a significant breakthrough for neuroscience, a team of researchers led by Marta Paterlini at the Karolinska Institute in Stockholm has provided strong evidence that the adult human brain can undergo neurogenesis, specifically in the hippocampus—a region crucial for learning, memory, and emotions. This process involves the formation of new neurons from neural progenitor cells, a topic that has been a subject of debate among neuroscientists for decades.
## Evidence for Neurogenesis
Using advanced methods such as single-nucleus RNA sequencing, flow cytometry, and machine learning, the researchers were able to identify and localize proliferating neural progenitor cells in adult human brain tissue. These techniques allowed them to detect cells with the genetic signature of neural progenitors.
However, the study found significant variation among individuals, with some adults showing higher levels of new neuron formation than others. In fact, five out of 14 adults did not show evidence of continued neurogenesis.
## Implications for Brain Health and Diseases
### Brain Health
The discovery of neurogenesis in the adult brain suggests a level of brain plasticity, which could be crucial for learning and adapting throughout life. This ability to form new neurons might help maintain cognitive function as we age.
### Diseases like Alzheimer's
Understanding neurogenesis could inform new therapeutic approaches for neurological diseases. For instance, enhancing or preserving neurogenesis might help counteract the neural loss seen in conditions like Alzheimer's disease. If neurogenesis contributes to brain resilience, then promoting it could be a strategy to manage or prevent the progression of neurodegenerative diseases.
However, more research is needed to fully understand how neurogenesis impacts brain health and disease and to explore its therapeutic potential. The recent findings provide a strong foundation for future studies to investigate these implications further.
The study, which was published in the journal Science on July 3, 2023, analysed over 400,000 individual nuclei of hippocampus cells from 24 people, and looked at 10 other brains using other techniques. The brains studied were from people of various ages, including children and teens.
The researchers used advanced techniques, including single-nucleus RNA sequencing and machine learning, to examine brain tissue samples from international biobanks. Nine out of 14 adult brains analysed with one technique showed signs of neurogenesis, while 10 out of 10 adult brains analysed with a second technique bore new cells.
The newer technologies enabled the researchers to detect the new brain cells at various stages of development. The team used fluorescent tags to mark the proliferating cells and built a machine learning algorithm to identify cells that would turn into neurogenic stem cells. The researchers used two cutting-edge imaging methods to map the location of new cells in the brain tissue.
The study's findings could have significant implications for the clinical neuroscience community. The fact that adult brains can sprout new neurons transforms how we think about lifelong learning, recovery from injury, and the untapped potential of neural plasticity.
Experts agree that the study provides strong evidence for adult neurogenesis. Dr. W. Taylor Kimberly, chief of neurocritical care at Massachusetts General Brigham, suggested exploring whether the adults who produced new brain cells did so in response to a neurological disease, such as Alzheimer's, or whether adult neurogenesis is a sign of good brain health.
Comparing patients who have dementia to "super agers" who are cognitively resilient in old age could help uncover the link between neurogenesis and disease, potentially leading to treatments. The dividing precursor cells were found in the same spots where animal studies have shown that adult stem cells reside, not just in babies and young kids, but also in teenagers and adults.
This groundbreaking research puts to rest the long-standing debate about whether adult human brains can grow new neurons, opening up a world of possibilities for understanding the human mind and brain health.
- The study's findings suggest that the ability to form new neurons in the adult human brain, a process known as neurogenesis, could be crucial for maintaining cognitive function as we age.
- Understanding neurogenesis could potentially inform new therapeutic approaches for neurological diseases, such as Alzheimer's, by enhancing or preserving neurogenesis to counteract neural loss.
- The variation in new neuron formation among individuals implies that mental health, fitness and exercise, health and wellness, nutrition, and aging could play significant roles in influencing the occurrence of neurogenesis.
- The discovery of neurogenesis in the adult brain could have far-reaching implications for the field of neurology, particularly in understanding neurological disorders like Alzheimer's and dementia, and potentially leading to treatments based on the differences between "super agers" and those with neurodegenerative diseases.
