European scientists make important advances in stroke research

Brussels, 6 November 2006

German researchers have made new discoveries that may significantly reduce the harmful effects of a stroke. Scientists from several different research institutions and universities in Germany studied the effects of the naturally occurring brain protein known as Granulocyte-Colony Stimulating Factor, or G-CSF. They have established that G-CSF retains its therapeutic effects even when injected up to three days following a stroke. This new research could prove to be an important step in the development of stroke medication.

The results of their study, recently published in the open access journal BMC Biology, shows that G-CSF, a protein that controls the formation of neurons and neuron rejuvenation by triggering the production of white blood cells, is effective in restoring motor function in rats that have suffered a stroke. When injected only a few hours after a stroke, the protein is capable of reducing the size of the area in the brain affected by one third. In addition, when administered days after the stroke, it is beneficial in helping the animals recover proper motor function.

G-CSF had already been known to aid in the recovery of a stroke, but this is the first time it has been shown that delayed treatment is also successful. Researchers looked at two different scenarios to study the extent of G-CSF's beneficial qualities.

Firstly, they looked at its ability to reduce the overall area of the brain affected by a stroke, which is established by measuring the presence of dead neurons. For rats that received the injection four hours after a stroke, the size of the affected area is reduced by 34.5 percent.

The second phase of the study examined the functional performance of animals that received injections 24 to 72 hours after a stroke for up to ten days. These rats exhibited a marked improvement in physical abilities and coordination over other rats that were given an inert injection.

These findings are expected to lay the foundations for future G-CSF research in humans, and eventually the development of important medications to treat stroke sufferers.

Of the several different types of stroke, this study looked at the most common, known as ischemic stroke. Ischemic stroke refers to the condition where a blood vessel becomes blocked, thereby partially or totally restricting blood flow to the brain. It is responsible for 85 to 90 percent of all strokes.

Strokes are currently the third leading cause of death in Europe, responsible for approximately 650,000 deaths per year, and the leading cause of disability in older Europeans. It represents a significant burden on health care management systems in Western Europe, accounting for up to three to four percent of total costs.

The study was conducted by Armin Schneider from Sygnis Bioscience AG (formerly Axaron Bioscience AG) in Heidelberg, Germany, and Wolf-R?diger Sch?bitz from the Neurology department in M?nster, Germany, together with colleagues from the universities of Heidelberg and Erlangen.