On the 4th of September, in the prestigious magazine PloS One, Tiago Fleming Outeiro, head of the Unit of Cell and Molecular Neurosciences at the Institute of Molecular Medicine (IMM) published, along with researchers from the USA, a study that shows new clues about the action of dopamine, a central nervous system stimulant, on Parkinson’s disease.

The study was carried out at Harvard Medical School (USA) and at the IMM, and had the collaboration of Portuguese, American and German researchers.

Parkinson’s disease is characterised by the degeneration and death of neurons in a region of the brain, the substancia nigra.

Despite one not knowing about important aspects of the molecular mechanisms responsible for the disease, it is known that at its base is the formation of protein aggregate within the neurons, namely a small protein called alfa-synuclein. In the neurons of Parkinson’s disease sufferers the alfa-synuclein takes on an altered form, which provokes its aggregation into agglomerates that are toxic for the cells.

The study now published shows that the alterations in form suffered by alfa-synuclein may be induced by dopamine, suggesting a role by dopamine in the formation of the protein aggregates characteristic to Parkinson’s disease. Dopamine is a central nervous system stimulant, a precursor of adrenalin and noradrenalin, involved in psychological dependence on several vices and in the degeneration of the neurons in Parkinson’s disease. The results published today also provide a possible explanation for previous observations, which revealed that the neurons producing/receiving dopamine are more vulnerable to the cell death characteristic to Parkinson’s disease.

“Our work suggests that the vulnerability of neurons in Parkinson’s disease is related to dopamine’s capacity to favour forms of alfa-synuclein that lead to the appearance of protein aggregates”, states Tiago Fleming Outeiro, the first author of the study and IMM researcher. “In this work we have identified these specific forms of alfa-synuclein; we now hope that our results might allow us to better understand the molecular mechanism that leads to Parkinson’s disease, as well as to find new forms of prevention or therapy”, continues Tiago Fleming Outeiro.

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Institute of Molecular Medicine
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