Antioxidants halve the damage caused by stroke

Multitudes of animal studies have shown that brain damage after stroke can be reduced dramatically with antioxidants. Several clinical studies with people are underway.

Stroke is, after heart disease and cancer, one of the most common causes of death in Western countries. Many of those who survive have the misfortune of suffering the effects of brain damage, including paralysis. It is projected that more people will get strokes as the population ages.

Can this gloomy prospect be mitigated? Many studies have shown that antioxidants can both prevent stroke and decrease the brain damage due to stroke. This fascinating subject has been analysed in a high quality analysis from the pharmacological laboratory of the Rene Descartes University in Paris.

In most cases strokes are not caused by a bleed in the brain, but by blood clots which get stuck in the brain’s blood vessels. These clots either develop in the brain’s large arteries or are brought with the blood from another place in the body. Either way, the effects are the same. The flow of blood to a part of the brain is cut off so that it does not get oxygen and dies. This can cause paralysis of differing degrees in the opposite side of the body.

This is where antioxidants come in. They combat free radicals, which are the cause of the greatest part of the brain damage. The free radicals are created during the time when the brain is starved of oxygen. When the blood clot is broken down, either by the body or medically (which is possible up to three hours after the appearance of the first symptoms) the renewed blood flow, called reperfusion, unfortunately causes a massive production of free radicals. This worsens the brain damage. Regardless of whether the flow of blood can be restored or not, the result can be destructive.

Why do these free radicals appear in tissue which has been starved, either entirely or partially, of blood? The article examines the possible explanations. Some enzymes which normally deactivate free radicals stop working. Furthermore, the weakening of the mitochondria (the energy factories of the cells) pays a role. The mitochondria are responsible for the handling of oxygen within the cells, and when they are weakened they leak free radicals. It has been proven that brain damage becomes worse when these free radicals are released.

Therefore it is logical to believe that antioxidants can limit the damage. This agrees with a large number of studies done on animals. In these studies, the damage was reduced by more than 50% by treating the animals beforehand with antioxidants such as NAC (n-acetyl-cysteine), resveratol (the colouring agent in red wine), lipoic acid, or melatonin. Vitamin E has also been able to halve (or more) the damage. The treatment has naturally worked best when it was started quickly. Fast help is double help.’

What can the average person do? The summary concludes that antioxidants are “with certainty some of the most promising measures against stroke,” and that they are of “great interest” in combination with the medical breakdown of blood clots used today. You can choose for yourself, but it is worth pointing out that regular intake of antioxidants is believed to prevent the possibly tragic effects of stroke.


Reference:
Isabelle Margaill et al. Antioxidant strategies in the treatment of stroke. Free Radical Biology and Medicine 2005;39:429-43.