Monday, June 15, 2009

Brain-Derived Neurotrophic Factor

The brain-derived neurotrophic factor (BDNF) is a neurotrophin (growth factor for neurons) which acts on the hippocampus, basal forebrain, and frontal cortex. These areas of the brain are involved in important functions of memory and cognition which are closely linked with psychiatric illnesses.

A new study has proposed using BDNF levels as a means of distinguishing between BP depression and MDD citing findings of greater BDNF levels in persons with MDD than with BP depression. (1)

Another study also examining serum levels of BDNF among different psychiatric disorders found that there was no significant difference between groups of unipolar depression, BD-I, or BD-II. However, measurements were done during euthymic states whereas the previous study measured serum levels during acute depressive episodes.(2) Since it is typically during a depressive episode that a patient will present for medical attention, evaluating BDNF levels during this phase seems more prudent.

Results of research done into the effects of ECT on BDNF levels have shown no correlation. (3) (Yet another article I don’t have full access to so I can not critique the study design, but it would be interesting to know when BDNF serum levels were measured as there is likely to be a time delay effect)…

…Especially when there is other research out there with long follow up periods indicating an association between ECT responders and BDNF levels.(4,5)

There have also been many studies linking the positive effects of different antidepressants to increased BDNF serum levels.(6, 7)

References: 1, 2, 3, 4, 5, 6, 7

1 comment:

  1. BDNF is one of my favorite proteins (and Rita Levi-Montaclini is one of my favorite scientists for finding it!). A research lab that my lab collaborates with (tangentially) looks at BDNF's involvement in Parkinson's disease (, and its role in neurogenesis is sort of what got me into neuroscience in the first place.

    the discreet role that this "single" protein plays in so many different conditions is astounding. I had no idea that it was involved in distinguishing different degrees/manifestations of depression.