Stem cells as a breakthrough in stroke treatment?

Professor Keith Muir from Glasgow University claims that stem cells are a real chance for treatment of patients after a stroke. For years he and his team have been conducting research on usage of this method in practice. According to BBC he is currently trying to administer stem cells to the patients. The results turned out to be surprisingly good.

Stem cells are self-dividing cells with potential of being tissue specific. Regarding the range of this potential, there are pluripotent stem cells of embryonic origins and multipotent ones. Pluripotent stem cells may differentiate in all cell lineages. Their ability to replace damaged tissues by, to some extent, rebuilding it from the ground up was used in the therapy. In order to do that they have to be placed exactly in the area where their division is needed. Multipotent cells come from adult organism. Their source may be bone marrow, umbilical cord, placenta or fat tissue and the division potential is limited only to cell lineage from which they come from. That is why there is no need to place them in strictly specific place. The result of these cells division is not to replace damaged tissues, but to activate the organism to their regeneration. Regarding more predictable divisions, the usage of multipotent stem cells seems to be safer.

Why stem cells give hope in stroke treatment?

Various types of nerve cells lose their function as a result of ischaemia. That is why implanting the cells into already damaged neurons would be very difficult. Stem cells are affinite to damaged and inflammated tissues. What is more, they respond to natural signals of the organism. The team from Glasgow University claim that all types of stem cells might be used in stroke therapy, even patient’s own cells from the bone marrow. That is a proof for potentially wide availability of this kind of treatment.

Taking pathophysiology of the stroke into account, the scientists assessed optimal time of stem cells administration. According to their observations the cases in which stem cells are administered in a week time from ischemic episode have the best prognosis. Stem cells successfully counteract processes of apoptosis, the loss of angiogenesis and immunomodulation ability which occur in a week after a stroke.

The basis for consideration of professor Muir’s team were results of research on animals published by Hicks et. al. They examined a group of 69 rats with induced occlusion of middle cerebral artery. The animals experienced significant defects of motor and cognitive functions as a result of the big ischemic focus emergence. The scientists observed the dysfunctions and their regressions after administering stem cells. The results were promising: in 97% of rats motor, sensory and balance functions returned and 100% of rats begun to use running track and walk again.

According to BBC News release, professor Muir announced his results of using the therapy in patients after a stroke on European Stroke Conference in London.

9 patients between 60 an 80 years old after stroke who experienced it in a time from 6 months to 5 years before the therapy usage were the research group. They suffered from various consequences of the loss of sensory and motor functions including complete paralysis. In order to conduct a research the patients were placed in Southern General Hospital in Glasgow and were taken special care of. Then, every patient have had stem cells injected into the place where the brain tissue was damaged. None of the patients experienced side effects of the therapy and in 5 of them slight improvement of the state of health was observed. The patients with complete paralysis started to move their fingers and contact with surrounding. A patient with balance disorder and left hand paresis was able to walk on his own and even tie shoelaces. Professor Muir claims that the increase of patients’ independence surpassed his expectations. It wasn’t proved whether the improvement of health was a direct result of the therapy or whether it stemmed from the placebo effect.

The research which are conducted by the team from Glasgow are the first of such kind in the world and they need further clinical trials in order to confirm the effectiveness and safety of the treatment. Current reports give hope for breakthrough in stroke therapy which has not changed for years.



Written by: Julia Rudnicka, Anna Kozioł

Source:
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Would you like to know more? Watch on MEDtube.net: Stroke – 3D Medical Animation

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