Brain fertiliser nurtures new hope for stroke survivors

Friday, 25 May 2018


A hormone already at our fingertips could provide a simple answer for a first-of-its-kind treatment to promote ‘brain fertilisers’ and significantly improve quality of life for stroke survivors, potentially even months or years after experiencing a stroke.

Dr Lin Kooi Ong and A/Prof Rohan Walker

In Australia, someone suffers a stroke every 10 minutes, with memory loss and learning difficulties just some of the side-effects for up to 80 per cent of survivors. However, new research has demonstrated an encouraging link between the administration of growth hormone and an improvement in cognition after experiencing stroke.

A team of researchers from the University of Newcastle and Hunter Medical Research Institute worked in collaboration with leading endocrinologist Professor Jörgen Isgaard from the University of Gothenburg, Sweden to make the discovery, published in the prestigious journal Stroke.

“We are proposing that growth hormone could play a critical role in brain repair after injury. Specifically, we found that growth hormone treatment after stroke significantly improved learning and memory performance – a promising development for survivors around the world,” co-author and University of Newcastle neuroscientist Associate Professor Rohan Walker explained.

Growth hormone and its role as a novel therapy

Growth hormone (GH) is a peptide hormone released from the pituitary gland, a tiny organ found at the base of the brain. The hormone promotes cell-growth throughout the body, including bone and muscle repair.

Although naturally occurring, synthetic GH is already approved, commercially available and predominantly used in treatment for GH deficiency, an encouraging prospect for the new research to quickly translate to clinical trials.

Previous studies have shown GH to have beneficial effects in promoting cognition post brain injury, however co-author and post-doctoral research fellow, Dr Lin Kooi Ong, said their work refining treatment methods in stroke survivors was vital moving forward.

“Although already used in medical treatment, this is the first time growth hormone has been looked at in this application. Our findings show that a boost of growth hormone in survivors could be a new link between stroke and recovery,” Dr Ong said.

A vital boost for cognitive repair

The research team evaluated the effects of administering GH at 48 hours post-stroke for a period of 28 days.

Particular focus was placed on the method of drug delivery, utilising an implantable system for controllable GH supply. They also assessed cognitive performance and analysed tissue samples to ascertain biological changes in the brain.

“Our results show a significant improvement in learning and memory tasks after the therapy, as well as a reduction in neural tissue loss.

“We also found that growth hormone treatment promoted ‘brain plasticity’ such as new blood vessel growth and the repair of neuronal networks after stroke, as well as a robust increase in the levels of neurotrophic factors or ‘brain fertilisers’ which promote cognitive functionality.

“The findings provide exciting new pre-clinical evidence for the use of GH as a therapeutic tool in the recovery phase of patients after stroke, and have the potential to change treatment altogether,” Dr Ong said.

Taking important steps towards recovery

With the research producing encouraging results in a pre-clinical environment, the team hope to secure further funding to begin clinical trials to further explore the effects of GH on different age groups, develop the administering method, and explore timing and dosage.

Co-author, Professor Michael Nilsson, Director of the Hunter Medical Research Institute and leading neuroscientist, neurologist and rehabilitation medicine specialist, said the new finding was an important step in stroke rehabilitation.

“Stroke was once a leading killer in Australia, but we have made significant progress in reducing deaths as a result of stroke. Whilst this is a great achievement, our community is faced with the new challenge of treating and rehabilitating survivors, hence the importance of this work.

“Stroke recovery can be a long and difficult process, with almost half a million survivors in Australia. Often, the consequence of stroke is severe and effects can be long-lasting.

“This encouraging discovery will be a welcome development for all those touched by the devastation stroke can leave behind,” Professor Nilsson said.

Could be a case of never too late

Dr Ong is hopeful the team’s important work will continue to evolve, a factor which is also true for the brain.

“A common misconception about the brain is that it stops developing once you reach a certain age. We know that the brain is constantly repairing and evolving, which is why you hear of incredible recoveries after brain injury.

“With this knowledge, we hope to secure more funding to begin clinical trials and explore whether GH treatment could be something administered successfully months or even years after stroke, giving new hope to survivors around the world,” Dr Ong said.

* Collaborators include Dr Lin Kooi Ong, Professor Jörgen Isgaard, Professor Michael Nilsson, Associate Professor Rohan Walker, Dr N. David Åberg (University of Gothenburg), Associate Professor Patricia Crock (John Hunter Children’s Hospital), Dr Andrew Bivard (Department of Neurology, John Hunter Hospital) and Professor Sarah Johnson.

* HMRI is a partnership between the University of Newcastle, Hunter New England Health and the community.