A molecule extracted from green tea leaves or pine cones may be able to reduce the brain damage from strokes, say scientists.
Gallotannin, and nobotanin B - found in a Japanese flower - both cut the damage from a simulated stroke in mouse brain cells grown in the laboratory.
However, there is no guarantee that they will work as well in a real patient.
The hours following a stroke are crucial to the future prospects, or even survival of the patient.
The stroke itself is caused by a halt to the blood flow to brain cells, either caused by bleeding on the brain, or by a blood clot lodged in a vessel.
However, although this kills some brain cells, once the blood supply is restored in the subsequent hours, many more cells tend to die.
This destructive reaction is still not fully understood, although scientists have found that a chemical signalling system has a role.Source BBC News