Oct. 25, 2021 — Star-shaped cells in our brains called astrocytes play a crucial role in helping us think, move, and breathe. They nourish our neurons, the cells that transmit messages throughout our brain and nervous system to control our bodily functions.

A new study in mice suggests that astrocytes also may play a negative role in our brains. When these cells encounter injured neurons, they release toxic fatty acids that could contribute to the tissue damage that occurs with dementia and other neurodegenerative diseases.

After researchers made this discovery using mice, they genetically engineered the animals to block production of these fatty acids. Their aim was to see if stopping production of these toxins prevented nerve cell destruction.

In the modified mice, 75% of the nerve cells survived, compared with 10% of such cells in animals with normally functioning astrocytes, according to the findings, which were published in Nature.

These toxic fatty acids do not affect healthy cells, the study team noted. The effects may be confined only to nerve cells that are damaged, injured, or mutated.

These findings are preliminary, and the methods the investigators used in mice aren’t ready to be used in human studies. The researchers suggest that halting production of the fatty acids might one day be used to treat conditions such as dementia, multiple sclerosis, Parkinson’s disease, and Huntington’s disease. The approach might be safer than attacking astrocytes directly, as they still are needed to nourish healthy neurons.