Depression study finds evidence of serotonin signal transduction disturbances

Depression study finds evidence of serotonin signal transduction disturbances
Depression: evidence of serotonin signal transduction disturbances

Depression and anxiety disorders are the most common psychiatric disorders. Over the last few years, molecular brain imaging using Positron Emission Tomography (PET) has helped us to identify important mechanisms involved in the development and treatment of these disorders, particularly those associated with the serotonin neurotransmitter system. The drugs that are used for these conditions (SSRIs) were developed 30 years ago. To celebrate this anniversary, a team from MedUni Vienna, led by Siegfried Kasper, Director of the University Department of Psychiatry and Psychotherapy, has summarised the latest status of global research in this field in the leading journal, The Lancet Psychiatry.

"People laughed at us when we started treating depression with SSRIs (selective serotonin reuptake inhibitors) 30 years ago," explains Siegfried Kasper, who is also one of the pioneers of this method of treatment. "Today it is State of the Art and we are able to quantify disturbances in serotonin signal transmission in the as the cause of depression and ." 80% of those suffering from depression are treated with SSRIs – the success rate is around 70%. Kasper: "Their quality of life is enhanced and there is a significant and lasting improvement in their motivation and mood."

Quantifiable mechanisms

Using Positron Emission Tomography (PET) from nuclear medicine, it is possible to quantify receptors, transporters and enzymes, in order to diagnose neurochemical differences in brain disorders but also to make a detailed analysis of the effects a drug has on the brain.

For example, it was also shown that the level of (SERT) is greatly reduced in certain parts of the brain in patients with depression. At the same time, PET showed that SSRIs are a very effective pharmacological first-line therapy that brings about specific changes in the activity of the serotonin system. The serotonin transporter (SERT) is a cell membrane protein that facilitates return of the neurotransmitter serotonin (commonly known as the "happy hormone") into the cell. The activity of the serotonin transporter influences neural networks in the brain that are changed in depression. The serotonin transporter therefore also serves as a point of attack for the main antidepressants, such as SSRIs.

The current study is the result of a collaboration with the Neurobiology Research Unit of Copenhagen University Hospital. Rupert Lanzenberger's research group at the University Department of Psychiatry and Psychotherapy, under the direction of Siegfried Kasper, is one of the leading international research teams in the field of PET brain imaging in . The underlying mechanisms for this were investigated in Vienna, in collaboration with the University Department of Radiology and Nuclear Medicine.


Explore further

Testosterone helps to bind antidepressants in the brain

More information: "The serotonin transporter in psychiatric disorders: insights from PET imaging." The Lancet Psychiatry, 2015, Aug; 2(8):743-55. www.ncbi.nlm.nih.gov/pubmed/26249305
Citation: Depression study finds evidence of serotonin signal transduction disturbances (2015, August 26) retrieved 23 August 2019 from https://medicalxpress.com/news/2015-08-depression-evidence-serotonin-transduction-disturbances.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.
56 shares

Feedback to editors

User comments

Aug 27, 2015
"People laughed at us when we started treating depression with SSRIs (selective serotonin reuptake inhibitors) 30 years ago," explains Siegfried Kasper, who is also one of the pioneers of this method of treatment. "Today it is State of the Art and we are able to quantify disturbances in serotonin signal transmission in the brain as the cause of depression and anxiety disorders."

SSRIs are no longer state of the art (and haven't been for a few years, it's just that development along other lines has stalled) and they haven't ever established what causes disturbances in the transmission of serotonin in the first place (it's like saying your broken leg is the cause of your inability to walk without addressing the fact that someone hit you in the shin with a baseball bat).

Aug 29, 2015
"PET showed that SSRIs are a very effective pharmacological first-line therapy that brings about specific changes in the activity of the serotonin system."

Maybe the "specific changes" can explain the suicidal and homicidal thoughts some people have when on SSRi type medications?

The above study would suggest that depressed patients have a chemical imbalance, ergo a disease of the brain. Yet, despite no scientific evidence to support the chemical imbalance this theory is still taken at face value by many of the professionals that prescribe these drugs.

It would be enlightening to see a study that could, once and for all, prove that depressed people have a chemical imbalance. I've read the claims but have yet to see any such evidence to back up these claims.

Over to you Kasper.

Aug 30, 2015
Before announcing any cure or treatment for depression and anxiety, perhaps a definitive scientific explanation of what is depression and anxiety, is required.

Hopefully its described better than mild, moderate or severe.

We have surely made progress .........

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more