Exploiting a new genetic model in the study of Parkinson's disease
Parkinson's disease is the second most widespread neurodegenerative disease in the world, with an estimated 1.2 million sufferers in Europe alone. One Marie Curie Fellow is carrying out innovative genetic research that could one day lead to a better prognosis for patients.
The risk of Parkinson’s increases with age: approximately 1% of people over 60 have it, rising to 4% for those over 80. The progressive nature of the disease makes it particularly devastating for patients and their families, and as the average lifespan continues to increase, the proportion of people suffering from Parkinson’s is also growing.
Aside from Parkinson’s disease, there is a whole spectrum of other Parkinson’s-like neurological disorders, some but not all of which are hereditary. Many cases are ‘sporadic’, i.e. occurring in an isolated or seemingly random way. Ongoing research has revealed a number of genetic mutations linked with sporadic Parkinson’s cases, enabling scientists to start to understand some of the specific cellular mechanisms at work.
“It is already widely known that the mitochondria, the cell’s powerhouses, play a part in Parkinson’s disease progression,” says Marie Curie Fellow Suvi Marianne Vartiainen, a 35-year-old researcher from Finland.
Now working on the Dromit project at the University of California, Los Angeles, Ms Vartiainen explains: “My first aim has been to develop a cell-culture method using fruit fly neurons, in order to unravel the chain of events that lead to Parkinson’s disease, including the role of the mitochondria.”
Ms Vartiainen says the fruit fly model is particularly useful – because the species has been so well studied and its genetic make-up so well mapped, it presents a unique opportunity to shed light on neuronal death in human patients.
“There are ready-made, functionality tested, genetically manipulated flies and fly cells available from government-funded centres,” the researcher says. “These fly stocks are available for the scientific community at a very affordable price. We can order transgenic flies, gene knock-outs and genetic mutants from these collections, basically allowing us to ‘visualise’ the genetic functioning of flies and, in this case, fly neurons.”
Specifically, research involves exposing fly cells to toxins that induce Parkinson’s in humans. One group of cells is normal while another has a known genetic manipulation that makes them resistant to these toxins. By comparing the effects of exposure in these two groups, the fellow says she hopes to get a deeper understanding of human neuropathology.
The ingenuity and originality of using a non-mammalian model was a key starting point for her project. “The organism I am using is very versatile and fast to work with. Testing new ideas is relatively inexpensive and time-efficient.”
Potential for new treatment?
Current treatments for Parkinson’s and Parkinson’s-like diseases offer only partial and temporary relief, being unable to address the underlying neuropathology. Ms Vartiainen says her work could make a difference, but she cautions it is still early days. “Legislation has been very unfavourable towards treatments that involve genetic manipulation, and despite mountains of convincing data, no one I know has yet been able to make a genetic therapy available for patients.”
On the other hand, over the longer term, she says, the work could lead to the discovery of chemical drug targets. In a best-case scenario, a link between the different disease mutations could be identified, enabling the development of drug-based treatments.
“At some point,” Ms Vartiainen hints, “a bigger player is going to have to step in, such as a big pharmaceutical company with the money and muscle to perform the required tests for a pharmaceutical compound.”
In the meantime, Ms Vartiainen says the international experience she has gained during her Marie Curie Fellowship has been invaluable. “I have been able to learn multiple techniques and, most of all, develop my scientific thinking. My new collaborative relationships will continue after my return to Finland and I am very hopeful about being able to publish my findings.
“Without the Marie Curie grant, this would not have been possible. I am very grateful for the support and I will promote these grants to my fellow researchers.”