Stem cells may not be useful in Alzheimer's treatment

As the world focuses on the death of Ronald Reagan from Alzheimer's disease, lobbyists are taking the opportunity to push research into human embryonic stem cells (ES cells), a potential treatment. But members of the scientific community have expressed concerns that Alzheimer's is being used to promote stem cell therapy, despite not being the most promising treatment.

Unlike Parkinson's, a neurodegenerative disease that affects a single area of the brain, Alzheimer's causes the loss of large numbers of neurones (nerve cells), with damage scattered across the brain. This means that stem cell transplants, intended to re-grow damaged tissues, may prove ineffective in the treatment of Alzheimer's patients. Although experiments have been carried out with mice, clinical use remains 'on the horizon' according to Fred Gage, a professor at San Diego's Salk Institute, whilst Lawrence Goldstein of the University of California admits, 'we don't even know what cells to replace initially'.

Direct treatment, such as targeting the protein clumps (known as amyloid) that cause the disease, may provide more immediate solutions. With amyloid as a focus, Marylin Albert of the John Hopkins University is optimistic that 'in five years, or certainly ten years, we'll have much more effective treatments'. Other possibilities include drugs that strengthen the synapses, the connections between neurones.

Ronald McKay, of the National Institute of Neurological Disorders and Stroke (USA), described stem cell transplants for Alzheimer's as 'a fairy tale', but transplants are not stem cell's only use. The versatile tool that they are, ES cells may provide the key to unlocking the cellular mechanisms behind the disease and they could be used in culture to test the efficacy of drugs before trials in humans.

So where does this leave human embryonic stem cell research? Such negative opinion may give President Bush's administration the ammunition they need to stick to their guns. Despite a 58-strong petition from the Senate, which even contained signatures of Republican party members, Trent Duffy, a spokesman for the President, said, 'There's a perception that if we go forward there would be a cure tomorrow. That's not the case'.