Nav: Home

A biological mechanism for depression

April 21, 2020

University of Illinois at Chicago researchers report that in depressed individuals there are increased amounts of an unmodified structural protein, called tubulin, in lipid rafts -- fatty sections of a cell membrane -- compared with non-depressed individuals.

Their findings are published in the Journal of Neuroscience.

Tubulin is part of a protein complex that provides structure to cells. This complex also is involved in binding a specific protein called Gs alpha, or Gsa, which is a signaling molecule that conveys the action of neurotransmitters like serotonin.

Previous work established that high levels of Gsa were in the lipid rafts of depressed individuals and that Gsa lost effectiveness when in those lipid rafts. Gsa moved out of the lipid rafts after treatment with antidepressants or after using a drug inhibitor for histone deacetylase 6 (HDAC-6) -- an enzyme that removes modifications from tubulin -- suggesting a role of tubulin in depression as well.

Mark Rasenick, UIC professor of physiology and psychiatry at the College of Medicine, and colleagues analyzed post-mortem brain tissue from individuals with and without a diagnosis of depression to determine the location and degree of modified tubulin. A subgroup for depression also included individuals who died by suicide.

"While some studies suggest that there are differences between depressed individuals who died by suicide and those that did not, we observed a profound decrease in the extent of acetylated tubulin in lipid raft membranes from brains of all depressed subjects," said Rasenick, who is also a research career scientist at the Jesse Brown Veteran Affairs Medical Center.

In all groups, there were no significant changes in the amounts of modified alpha tubulin, HDAC-6, or alpha tubulin acetyltransferase 1 -- a protein that adds modifications to tubulin. However, there was less modified tubulin found in the lipid rafts of both depression groups versus the non-depressed group. According to Rasenick, the data suggest that diminished tubulin acetylation may be essential in harnessing Gsa to lipid rafts during depression. Antidepressants reverse this process and allow fuller function of Gsa and the neurotransmitters that activate it.

PAX Neuroscience Inc., a company created by Rasenick, researches how Gsa localization could be a diagnostic biomarker in blood cells to identify individuals with depression. Now the company will explore tubulin-related depression therapeutics and diagnostics. This may add new approaches to therapy and create diagnostic platforms to determine, in just a few days, whether an antidepressant is working.

"This work is important because half of the people who appear to be suffering from depression don't seek treatment," Rasenick said. "This is likely due to the social stigma surrounding people with psychiatric problems. But having an identified biological basis for depression could help people to realize that depression is not 'their failure' and allow them to treat it like any other illness."
-end-
Harinder Singh, Justyna Chmura, Runa Bhaumik and Ghanshyam Pandey from UIC were co-authors.

Funding was provided by grants and awards from the U.S. Department of Veteran Affairs (BX001149 and BX 004475), the National Institutes of Health (RO1AT009169, R21 NS 109862 and RO1MH106565) and the American Heart Association (16POST27770113).

University of Illinois at Chicago

Related Depression Articles:

Children with social anxiety, maternal history of depression more likely to develop depression
Although researchers have known for decades that depression runs in families, new research from Binghamton University, State University of New York, suggests that children suffering from social anxiety may be at particular risk for depression in the future.
Depression and use of marijuana among US adults
This study examined the association of depression with cannabis use among US adults and the trends for this association from 2005 to 2016.
Maternal depression increases odds of depression in offspring, study shows
Depression in mothers during and after pregnancy increased the odds of depression in offspring during adolescence and adulthood by 70%.
Targeting depression: Researchers ID symptom-specific targets for treatment of depression
For the first time, physician-scientists at Beth Israel Deaconess Medical Center have identified two clusters of depressive symptoms that responded to two distinct neuroanatomical treatment targets in patients who underwent transcranial magnetic brain stimulation (TMS) for treatment of depression.
A biological mechanism for depression
Researchers report that in depressed individuals there are increased amounts of an unmodified structural protein, called tubulin, in lipid rafts compared with non-depressed individuals.
Depression in adults who are overweight or obese
In an analysis of primary care records of 519,513 UK adults who were overweight or obese between 2000-2016 and followed up until 2019, the incidence of new cases of depression was 92 per 10,000 people per year.
Why stress doesn't always cause depression
Rats susceptible to anhedonia, a core symptom of depression, possess more serotonin neurons after being exposed to chronic stress, but the effect can be reversed through amygdala activation, according to new research in JNeurosci.
Which comes first: Smartphone dependency or depression?
New research suggests a person's reliance on his or her smartphone predicts greater loneliness and depressive symptoms, as opposed to the other way around.
Depression breakthrough
Major depressive disorder -- referred to colloquially as the 'black dog' -- has been identified as a genetic cause for 20 distinct diseases, providing vital information to help detect and manage high rates of physical illnesses in people diagnosed with depression.
CPAP provides relief from depression
Researchers have found that continuous positive airway pressure (CPAP) treatment of obstructive sleep apnea (OSA) can improve depression symptoms in patients suffering from cardiovascular diseases.
More Depression News and Depression Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Debbie Millman: Designing Our Lives
From prehistoric cave art to today's social media feeds, to design is to be human. This hour, designer Debbie Millman guides us through a world made and remade–and helps us design our own paths.
Now Playing: Science for the People

#574 State of the Heart
This week we focus on heart disease, heart failure, what blood pressure is and why it's bad when it's high. Host Rachelle Saunders talks with physician, clinical researcher, and writer Haider Warraich about his book "State of the Heart: Exploring the History, Science, and Future of Cardiac Disease" and the ails of our hearts.
Now Playing: Radiolab

Insomnia Line
Coronasomnia is a not-so-surprising side-effect of the global pandemic. More and more of us are having trouble falling asleep. We wanted to find a way to get inside that nighttime world, to see why people are awake and what they are thinking about. So what'd Radiolab decide to do?  Open up the phone lines and talk to you. We created an insomnia hotline and on this week's experimental episode, we stayed up all night, taking hundreds of calls, spilling secrets, and at long last, watching the sunrise peek through.   This episode was produced by Lulu Miller with Rachael Cusick, Tracie Hunte, Tobin Low, Sarah Qari, Molly Webster, Pat Walters, Shima Oliaee, and Jonny Moens. Want more Radiolab in your life? Sign up for our newsletter! We share our latest favorites: articles, tv shows, funny Youtube videos, chocolate chip cookie recipes, and more. Support Radiolab by becoming a member today at Radiolab.org/donate.