ES cells show promise in Parkinson's treatment

In another stem cell study, scientists working for the US National Institutes of Health (NIH) have shown that mouse embryonic stem cells (ES cells) can develop into nerve cells that can then be used to treat Parkinson's disease in rat models. The report also appears in Nature Online.

The team, led by Dr Ronald McKay, added a gene,  called Nurr1 to mouse ES cells in culture, and exposed them to a series of growth factors. Nurr1 is involved in the development, or differentiation, of stem cells into nerve cells that produce the chemical dopamine. The loss of dopamine-producing nerve cells is a feature of Parkinson's disease.

The resulting cells were transplanted into rats that lacked dopamine-producing cells on one side of their brain, thus inducing Parkinson's disease-like symptoms on one side of their bodies. Another group of rats received transplants without the Nurr1 gene, and others had 'sham operations'. The research team found that the ES cells with Nurr1 'established functional connections with surrounding brain cells and began to release dopamine'. The rats showed significant improvements in their symptoms, while the rats which did not receive Nurr1 showed a little improvement.

Dr McKay said that 'what we are showing here is that we absolutely, definitely have the right cell'. But he added that while the results of the study show that nerve cells derived from ES cells may be useful for treating Parkinson's and other neurological diseases, they are 'still preliminary'. Studies are being planned with a view to eventually trying similar treatments in humans.