'Neural stem cells potentially be reactivated to form new neurons'

WASHINGTON: Neural stem cells that are quiescent or latent in some parts of the adult brain may one day become active and create new neurons. Yet, nothing is currently known about the change from quiescence to proliferation.

The role of cell metabolism in this process has been established by a team of researchers lead by researchers from the Universities of Geneva (UNIGE) and Lausanne (UNIL), along with a method for reawakening and reactivating these neural stem cells.

Researchers were successful in raising the number of new neurons in the mature and even old mouse brains. The journal Science Advances will publish these encouraging findings for the treatment of neurodegenerative illnesses.

Stem cells have the unique ability to continuously produce copies of themselves and give rise to differentiated cells with more specialized functions. Neural stem cells (NSCs) are responsible for building the brain during embryonic development, generating all the cells of the central nervous system, including neurons.

Neurogenesis capacity decreases with age

Surprisingly, NSCs persist in certain brain regions even after the brain is fully formed and can make new neurons throughout life. This biological phenomenon, called adult neurogenesis, is important for specific functions such as learning and memory processes.

However, in the adult brain, these stem cells become more silent or ''dormant'' and reduce their capacity for renewal and differentiation.

As a result, neurogenesis decreases significantly with age.The laboratories of Jean-Claude Martinou, Emeritus Professor in the Department of Molecular and Cellular Biology at the UNIGE Faculty of Science, and Marlen Knobloch, Associate Professor in the Department of Biomedical Sciences at the UNIL Faculty of Biology and Medicine, have uncovered a metabolic mechanism by which adult NSCs can emerge from their dormant state and become active.

''We found that mitochondria, the energy-producing organelles within cells, are involved in regulating the level of activation of adult NSCs,'' explains Francesco Petrelli, research fellow at UNIL and co-first author of the study with Valentina Scandella.

The mitochondrial pyruvate transporter (MPC), a protein complex discovered eleven years ago in Professor Martinou's group, plays a particular role in this regulation. Its activity influences the metabolic options a cell can use.

By knowing the metabolic pathways that distinguish active cells from dormant cells, scientists can wake up dormant cells by modifying their mitochondrial metabolism.