Cell Stem Cell: Immature neurons function differently in people resistant to dementia

Alzheimer’s disease does not always produce symptoms of the same severity. In some people, postmortem examinations reveal characteristic pathological changes even though they did not develop dementia during their lifetime. This preservation of cognitive function is known as cognitive resilience.

The researchers compared hippocampal samples from the Netherlands Brain Bank. The analysis included three groups: donors without identified pathology, patients with Alzheimer’s disease dementia, and people with pathological changes who had retained their cognitive abilities.

Using gene activity analysis and specialized computational methods, the team identified rare cells with features of immature neurons. These cells were found in all three groups, including donors whose average age was over 80.

The scientists had expected to find substantially more of these cells in people resistant to dementia. However, the differences in cell numbers were smaller than anticipated. More pronounced differences emerged in molecular programs: resilient donors showed better preservation of processes associated with cell survival and responses to damage, while signals linked to inflammation and cell death were weaker.

The authors suggest that immature neurons may support the surrounding tissue and help maintain the function of neural networks. However, the presence of immature cells does not prove that they have formed recently or that new neurons are continuously generated in the aging brain. Further research is needed to determine how these cells interact with neighboring cells and whether they actually contribute to protection against dementia.