New research into the causes of epilepsy, led by scientists at RCSI (Royal College of Surgeons in Ireland), has identified new approaches to drug therapy that could potentially revolutionise how epilepsy is treated in the future.

The study, published in the current edition of Scientific Reports, has identified a way to target the underlying cause of epilepsy, rather than masking the symptoms, and paves the way for the development of new drugs for the condition.

The researchers looked at regions in the brain distant from the normal sites of epileptic activity and found that in these areas, a molecule known as microRNA-22 was providing a protective function. The microRNA worked by blocking a cell receptor that normally promotes inflammatory responses in the brain leading to increased excitability that is characteristic of epilepsy. Without microRNA-22, the distant brain regions developed inflammation and began to generate seizures themselves. The scientists found that directly injecting the microRNA into hyper-excitable brain regions calmed the electrical activity and reduced seizures.

Professor David Henshall, from the RCSI Department of Physiology and Medical Physics and joint senior author on the study commented: "Epilepsy affects more than 37,000 people in Ireland and our study has shown promising results for the development of new treatments. We are looking forward to the next phase of the research which will potentially lead to a new type of drug that can tackle the underlying causes of epilepsy, reducing seizures and ultimately improving quality of life for people with the condition."

The first author on the study is Dr Eva Jimenez, Research Fellow, who worked with joint senior authors Professor David Henshall and Dr Tobias Engel, Lecturer, all based at the RCSI Department of Physiology and Medical Physics and numerous international collaborators.
The findings are a result of a major four-year collaborative effort to investigate molecular mechanisms of epilepsy development. Led by the team in at RCSI in Dublin, the work features academic and industry collaborators including Universidad Complutense de Madrid, Spain; Robert S. Dow Neurobiology Laboratories, Legacy Research Institute, Portland, Oregon, USA and Janssen Research and Development, LLC, Neuroscience, San Diego, California USA. 

The research was supported by a grant from Science Foundation Ireland's (SFI) Starting Investigator Research Grant (SIRG) and by EpimiRNA, an international consortium funded by the EU FP7 programme, coordinated by RCSI.