Why does the brain age faster in some of us? The new findings discovered

A new study published in Nature Medicine reveals that oligodendrocyte cells, which are supposed to protect nerve fibers, may become harmful with age and accelerate cognitive decline. Researchers identified low levels of the NRF2 protein as a possible cause, and an experiment in mice confirmed the causal link.

A new study published today (Wednesday) in the journal Nature Medicine reveals a surprising finding about brain aging. Researchers discovered that oligodendrocyte cells, whose role is to create a fatty insulating layer (myelin) around nerve fibers and protect them, may become harmful with age. In the brains of people with rapid cognitive decline, the myelin layer around large nerve fibers was particularly thick, which may disrupt the timing of communication between brain regions. At the molecular level, low levels of a vital protective protein called NRF2 were identified, which is responsible for clearing waste from the cell and protecting against oxidative damage. The hypothesis is that excess cells and crowding reduce the activity level of NRF2, turning the cells from helpers into harmers. An experiment in mice where the protein was 'turned off' showed that mice without the protein performed significantly worse on memory tests, strengthening the assumption that reduced protein activity is a key factor. The researchers emphasize that this is preliminary research and the causal proof comes from mice, and further studies in humans are needed.