Festival bites: BNA 2013 Day 1
Over the next four days BNA 2013: Festival of Neuroscience is filling the Barbican with an extravaganza of brain science. A lucky group of science writers from the Wellcome Trust are attending the Festival. Each day, we’ve asked them to give a short account of the seminars and lectures which they attend, to share the new research, stimulating discussions, and the unanswered questions, which they encounter. Today’s bite-sized pieces, from Theresa Taylor and Ryan O’Hare, offer a glimpse of the great range of events taking place on Sunday, the first day of the festival.
Plenary 1: Professor Karen Steel
By Theresa Taylor
“Hearing loss is not all about going to too many loud discos as a teenager,” said Professor Karen Steel from the Wolfeson Centre for Age Related Diseases at King’s College London. She was kicking off the BNA 2013 festival this morning (Sunday 7th April) with a lecture on her 30 years of research into the genetics of deafness.
Steel’s research uses mice as a model to identity the genes, and the physiological mechanisms which cause deafness. One in 850 children are born with permanent hearing impairments and half of over 70 year olds have hearing loss, but very few are given a molecular diagnosis. In addition, over half of childhood deafness is caused by a mutation in a single gene. This makes finding the underlying cause, in Steel’s words, a “real puzzle”.
By using mutant mice to investigate hearing loss Steel and her collaborators have identified several new genes, from hundreds of mutant lines, which could be implicated in hearing loss. Through comparing the various mutations found, Steel has confirmed that there is not a single mechanism leading to hearing loss, as mutations in different genes may have the same outcome but can effect entirely different processes within the ear.
Treating with antidepressants: Where are we now and where are we going?
By Theresa Taylor
When a patient starts taking anti-depressants, they aren’t expected to notice a change in their mood for a few weeks. But are they experiencing other unnoticed changes in outlook in the mean time? Dr Catherine Harmer director of the Psychopharmacology and Emotional Research Lab at Oxford University addressed this question during the symposium, Treating with antidepressants: Where are we now and where are we going?
Dr Harmer explained that a negative emotional bias underlies depression. This means people with depression are more prone to negative thinking about themselves and the world, as well remembering negative pieces of information. Dr Harmer’s team conducted a range of experiments with depressed patients, including asking them to remember negative and positive words. They found that after even just one dose of anti-depressants, patients moved from having a largely negative emotional bias, to remembering and interpreting information like their healthy counterparts. Their research also showed that the patients who had the greatest shift in their emotional bias at this early stage, often also made the most progress later at the clinical stage.
But why don’t the patients feel any different at this early stage if their medication has started to take effect? “You need the new information to come in, in order to act on that positive bias and for that new information to effect how you feel,” said Harmer. She suggested that these results could be applied in drug development, to assess if drugs are having an effect at this early stage, as well as in the management of individual patients’ conditions.
Epigenetics and neuroscience – how the ‘molecular toolbox of epigenetics’, affects the brain.
By Ryan O’Hare
The brain is a constantly changing environment, with neural connections forming and being cut, and cells dividing and differentiating, throughout its development. The ‘molecular toolbox’ of epigenetics adds an additional layer of complexity to the genetic machinery churning away inside our brain cells. Through adding or removing chemical tags to DNA and it’s scaffolding, it changes which genes are read and how they are expressed by cells, all without changing the DNA code itself. This can have a marked effect on our neurological condition. One of the difficulties researchers face in studying epigenetic changes is that they need to study living tissue – but how do we take brain tissue from a living person?
Professor Wilkinson of Cardiff University spoke of potential solutions involving screening for epigenetic markers. He also highlighted the turbulent nature of the epigenetic landscape in our brains, and the concerns around drug treatments which target epigenetic tags, suggesting that the same drug could have a variety of effects on a person depending on their current epigenetic state. Professor Wilkinson also discussed the controversial suggestion that these epigenetic, and supposedly temporary, changes to gene expression, could be passed on.
Early life stress and it’s long-term effects – experimental studies
By Ryan O’Hare
When we are under stress our bodies release a barrage of chemicals, chief among these are the stress hormones or glucocorticoids (GCs), such as cortisol. Exposure to these chemicals in the womb can have an impact on the developing brain of the foetus, and may be associated with a range of mood disorders in later life including depression and anxiety. This phenomenon, termed early life stress or ELS, was the subject of a talk by Professor Megan Holmes of the University of Edinburgh.
Professor Holmes explained the importance of an enzyme called 11-beta-HSD2 in protecting the foetus from high levels of GCs in the the blood of a stressed mum-to-be. The enzyme is expressed in the placenta, as well as the brain of the developing foetus, to convert stress hormones into an inactive, and less damaging, form. Professor Holmes explained that a lack of this enzyme in mice caused a decrease in birth weight, and affected the development and maturation of the brain, due to an excess of GCs. Work is ongoing to see whether the enzyme in the placenta or in the brain is key, although Professor Holmes expects it to be a combination of the two.
At the Festival today? Tell us what your highlights are and keep up to date with the latest Festival news on Twitter using the hashtag #BNAneurofest.
The scientific programme for BNA 2013: Festival of Neuroscience is not open to the public, but there are also public events happening throughout the week at the Barbican as part of the Wonder season. Including the Wonder Street Fair – a free public event bringing together science and art on the brain. There’ll be interactive exhibits, activities to help you explore the brain and much more. Visit the website for more information.