The fatty frontier of neonatal brain injury research

Brain injuries can affect anyone, but infants and their rapidly developing brains are particularly vulnerable. On a cellular level, they respond differently to damage than those of older people, but it’s not clear why.

Maria Ioannou, a University of Alberta professor of cell biology, is on a research journey to discover ways to improve outcomes following neonatal brain injury. She suspects some answers might lie with the lipids in infant brain cells.

Lipids are a group of biological molecules best known as fat. They have many functions throughout the body, including energy storage and communication between cells. Lipids can also be stored in globules — called lipid droplets.

With support from a WCHRI Innovation Grant, Ioannou and her team set out to explore how stress affects the formation of lipid droplets within neonatal brain cells. They focused on a form of stress called excitotoxicity, which occurs when nerve cells are overwhelmed by very high levels of neurotransmitters (chemical messengers in the brain).

“We found that if you induce cellular stress, you start to see lipid droplets form,” says Ioannou, who holds the Canada Research Chair in brain liquid cell biology. The droplets seem to minimize the damage of cellular stress, as the team hypothesized, but it isn’t clear why.

It’s also uncertain whether the protective benefits of lipid droplets cease once they exceed a certain threshold. And why do lipid droplets form most frequently in microglia, the brain’s immune cells, which account for just 10 to 15 per cent of all brain cells? That’s not clear either.

“We’re in the process of writing up the findings, though there is still much that remains to be studied,” she says. That’s the fate of discovery scientists like her: the more experiments they do, the more follow-up questions emerge.

She hopes clarity will come with future studies of lipid droplets. In time, she plans to pivot to research on lipid-based therapies for the treatment of neonatal brain injury.

“At the end of the day, WCHRI’s mandate is to improve the health outcomes of women and children,” she says. “Even though this is a discovery project, I think it has a lot of potential to do just that.”