Tuesday, October 29, 2013

The new type of antidepressant that could work in just DAYS rather than weeks or months

  • Research shows blocking a hormone receptor in brain induces fast-acting antidepressant effects in mice - it could lead to new drugs for humans
  • Selectively blocking these serotonin receptors significantly reduced depression-like behaviour in mice in just five days
  • Currently, only two drugs - ketamine and scopolamine - act rapidly. But due to severe side effects, neither is suitable for human use



  • A fast-acting antidepressant pill which could alleviate symptoms of depression within days is being developed.
    Medicines used currently can take weeks - and for some patients, months - before they begin to alleviate the symptoms of depression. 
    Now, scientists in the U.S. have discovered that blocking a hormone receptor in the brain induces fast-acting antidepressant effects in mice, indicating a potential new class of treatments for depression. 
    A fast-acting antidepressant treatment which could alleviate symptoms of depression within five days is being developed
    A fast-acting antidepressant treatment which could alleviate symptoms of depression within five days is being developed by scientists in the U.S.

    The study's senior author Dr Stephanie Dulawa, associate professor of psychiatry and behavioural neuroscience at the University of Chicago, said: ‘One of the biggest problems in the treatment of depression today is a delay in onset of therapeutic effects. 
    ‘There has been a great need to discover faster-acting drugs.’
    Dr Dulawa said the delayed onset of antidepressant medicines’ benefits can significantly impact patients, especially those with severe depression, who often spend months switching between ineffective medications.
     

    Currently, only two drugs - ketamine and scopolamine - act rapidly. However, due to severe side effects, neither is suitable for human use.
    In looking for a new class of fast-acting drug, Dr Dulawa and her team tested biological pathways that had previously been shown to have antidepressant effects but had never been studied for rate of onset. 
    They looked at different serotonin receptors – serotonin is a neurotransmitter that has been shown to regulate mood, memory and appetite.
    Medicines used currently can take weeks - and for some patients, months - before they begin to alleviate the symptoms of depression
    Medicines used currently can take weeks - and for some patients, months - before they begin to alleviate the symptoms of depression

    Of these subtypes, serotonin 2C receptors stood out. Selectively blocking these receptors in mice significantly reduced depression-like behaviour in just five days, compared to a minimum of two weeks for conventional antidepressant medication.
    The paper's lead author Mark Opal, a graduate student at the University of Chicago, said: ‘We observed fast-acting therapeutic effects in multiple behavioural tasks after we administered compounds that selectively block serotonin 2C receptors.
    ‘We began our measurements at five days, but we think there's a possibility it could be effective even sooner than that.’
    Dr Dulawa said serotonin 2C receptors normally inhibit the release of dopamine, another neurotransmitter commonly associated with mood, from certain neurons in the brain. 
    The researchers believe that when 2C is blocked, more dopamine is released into some regions of the brain. The team also observed a rise in the levels of biomarkers that indicate antidepressant effects are occurring.
    Dr Dulawa said the findings, published in the journal Molecular Psychiatry, are the first new biological mechanism that has shown the ability to rapidly alleviate symptoms of depression since ketamine and scopolamine, and it potentially represents a much safer alternative. 
    Some current antidepressants on the market already affect serotonin 2C receptors, although not selectively, and Dr Dulawa believes they are likely to be safe for human use. 
    The team is now investigating compounds suitable for clinical trials.
    Dr Dulawa said: ‘One of the primary advantages to our discovery is that this is much more of an innocuous target than others that have been identified.’


    Read more: http://www.dailymail.co.uk/health/article-2478789/The-new-antidepressant-work-just-DAYS.html#ixzz2jAMOFQdt 
    Follow us: @MailOnline on Twitter | DailyMail on Facebook