Excess calcium leads to inflammation that can cause ischemic strokes.
- Immune cells, called microglia, are flooded with calcium surges following ischemic strokes, which are caused by disruption of blood flow to the brain.
- Blocking these calcium surges can help control harmful inflammation and offer doctors a way to reduce the consequences of ischemic stroke.
- A drug has reduced these waves by 25% in mice.
Watch out for too much calcium. Already implicated in memory loss, excess calcium can lead to an increased risk of having a stroke. This discovery made by American researchers at the University of Virginia School of Medicine offers physicians a new approach to reducing the risk of stroke in patients. The results of the work were published on November 9 in the journal stroke.
waves of calcium
Immune cells, called microglia, are flooded with calcium surges following ischemic strokes, which are caused by disruption of blood flow to the brain. “These calcium surges trigger damaging inflammation that can worsen the effects of stroke”, continues Petr Tvrdik, author of the study. Blocking these calcium surges can help control harmful inflammation and offer doctors a way to reduce the consequences of ischemic stroke. “This publication culminates several years of research on this hitherto unknown aspect of stroke pathology.”, estimated Petr Tvrdik.
For several years, it has been known that the lack of blood flow to the brain during ischemic strokes causes waves of abnormal brain activity, called cortical spreading depolarizations (CSDs). These waves are harmful and can lead to further brain damage. Working on mice, scientists found that ischemic strokes trigger waves of calcium that travel through microglia immune cells. This calcium overload “triggers CSDs in a recurrent and progressive manner”, observed the researchers.
A promising drug
The researchers took it a step further and used a drug aimed at reducing calcium surges. The results showed, in mice, a reduction of these waves by 25%. This gives hope that a similar approach could be used to reduce the harmful effects of calcium surges in stroke patients,”although further research is needed”, they add.
