Brain’s ‘sea horse’ to ensure better treatment of mental disorders
Four scientists from the University of Copenhagen and Rigshospitalet, University of Copenhagen, have been delving into brain scans. The aim is to identify a specific biomarker – a ‘benchmark’ – that could help prevent memory loss, among other things, in psychiatric patients.
Mental disorders and cognitive impairment such as memory loss, attention deficiency and learning difficulties are very often inextricably linked in sufferers.
This applies to disorders such as depression and schizophrenia and it has a negative impact, in particular, on the sufferer’s social life and ability to remain in work.
It would therefore be extremely useful if we could identify a biomarker – a kind of biological benchmark – which can be used to determine whether certain biological, pharmacological and psychological treatments could prevent memory loss and other cognitive issues associated with mental disorders.
This biomarker has not yet been designed but four neuroscientists at the University of Copenhagen and Rigshospitalet, University of Copenhagen, believe that it should be possible. The team is led by Professor and Lundbeck Foundation Fellow Kamilla Miskowiak, and the four scientists have studied the hippocampus, an area of the human brain that literally resembles a sea horse. And in Latin, hippocampus actually means sea horse.
‘We’ve looked at a number of scientific studies based on MRI scans of the hippocampus of patients with mental disorders – for instance, people who’ve developed schizophrenia. And our findings indicate that hippocampal measures used in interventions to reduce cognitive dysfunction should be able to act as the biomarker we so badly need,’ says Professor Miskowiak.
Kamilla Miskowiak and her colleagues have recently published their results in a scientific review article in European Neuropsychopharmacology.
It shrinks
For some years now, neuroscientists have been aware that the hippocampus may shrink in volume in connection with depression, bipolar disorder or schizophrenia. This is obvious when we study MRI scans of the brains of people affected by these mental disorders.
The hippocampus plays a key role in learning and memory, but we have no idea why it seems to shrink when people suffer from depression. Or which came first – chicken or egg:
‘We can’t rule out that people with a genetic disposition for developing depression and a number of other mental disorders may be born with a smaller hippocampus,’ says Kamilla Miskowiak.
In recent years, neuroscientists – including Kamilla Miskowiak – have conducted trials in which people with depression or schizophrenia are given psychoactive drugs to see whether this improves their level of cognitive function. Substances used include the EPO hormone and lithium, an element already used to treat bipolar disorder and certain types of depression.
In several of these trials, systematic controls using MRI scans and memory tests proved that both EPO and lithium improved participants’ memories – and that hippocampal volume increased.
The scientists have no clear explanation as to why memory improves.
It may be linked to an increase in production of the specific proteins that play an important role both in generation of new brain cells and in the connection between brain cells.
However, Kamilla Miskowiak explains that the research team’s overall opinion is clear:
‘Our assumption is that it must be possible – in some way or other – to get the hippocampus to act as a biomarker when we design and select therapies to reduce the extremely inconvenient and painful cognitive dysfunctions often observed with mental disorders.’
Development activities
However, before hippocampal measures can be given biomarker status, there are a number of studies to be conducted, and the four scientists will now make a start on these.
‘We have to make sure that hippocampal growth is only seen in connection with initiatives to prevent cognitive impairment. And we’ll study this by performing a range of memory tests and MRI scans, both before and after the treatment programmes,’ Professor Miskowiak explains.
According to Kamilla Miskowiak, if hippocampal measures are given biomarker status, researchers will be able to include MRI scans of the hippocampus in the process to design therapies for the cognitive dysfunction that goes hand in hand with a mental disorder:
‘Both when testing novel interventions – typically, pharmacological preparations, drugs. And when investigating whether medicines approved for other purposes may have a positive effect on memory.’
Caroline Vintergaard Ott, Claire Bergstrom Johnson and Julian Macoveanu were co-authors of the scientific article.