Featured Research

from universities, journals, and other organizations

Hippocampal volume loss in depression reflects glial loss

Date:
December 17, 2013
Source:
Elsevier
Summary:
Depression has been associated with reduced volume of the hippocampus in magnetic resonance imaging studies in humans. A new study now clarifies the cellular basis of these volumetric changes, which have been unclear until now. Beginning in the 1980s, a series of studies in rodents suggested that an area of the hippocampus, a brain region implicated in mood and memory, was particularly vulnerable to stress. When analyzing the brain tissue in detail, they reported loss of nerve cells called neurons with stress.

Depression has been associated with reduced volume of the hippocampus in magnetic resonance imaging studies in humans. A new study just published in Biological Psychiatry now clarifies the cellular basis of these volumetric changes, which have been unclear until now.

Beginning in the 1980s, a series of studies in rodents conducted by Robert Sapolsky and other investigators suggested that the CA3 area of the hippocampus, a brain region implicated in mood and memory, was particularly vulnerable to stress. When analyzing the brain tissue in detail, they reported loss of nerve cells called neurons with stress. Other rodent studies described reductions in the birth of new neurons in the hippocampus associated with stress.

Collectively, these studies suggest that stress-related disorders, such as depression and posttraumatic stress disorder, might be associated with hippocampal volume loss. This hypothesis is supported by numerous studies reporting reduced hippocampal volume in depressed patients.

The current study, led by Dr. Carol Shively at Wake Forest School of Medicine, extends our insight into hippocampal volume loss associated with depression by studying female nonhuman primates called cynomolgus monkeys. The researchers studied only female monkeys because, while depression is the leading cause of disability in young and middle-aged adults, it is twice as common in women as men.

"In this study we observed unique features of the depressed nonhuman primate brain, in the hippocampus, that were unlike the rat and mouse models of depression that are currently used to develop depression medications," said Shively.

Monkeys have brains that share a lot of similarities with human brains, and medical research in primates can bridge important work being done in rodent models and in humans.

To conduct this study, Shively and her colleagues observed 16 female monkeys over 24 months, who were housed normally in stable social groups in the laboratory. Each monkey was observed weekly over the two year period and assessed for depressive behavior. Any observed depression occurred naturally, without experimental intervention or manipulation, since like humans, monkeys can become depressed.

Then, Stephanie Willard, a graduate student in the lab, examined the entire hippocampus and found that the reduced size of the hippocampus in the depressed monkeys was due to reductions in glia number and neuropil content. However, there were no differences in the number of neurons between the depressed and non-depressed monkeys. Glia surround and support neurons, aiding in communication throughout the brain. Neuropil is made up of a dense network of nerve fibers, their branches and synapses which connect glia and neurons.

"The current data highlight the glial sensitivity to stress," commented Dr. John Krystal, Editor of Biological Psychiatry. "Since glial loss can disturb neural communication in a number of important and well-defined ways, the current findings could have important implications for interpreting neuroimaging findings in depression and for the design of novel antidepressant treatments."

Shively agrees, adding that "new more effective medications for the nearly 15 million Americans suffering from depression are far more likely to be developed if they include studies of medication effects in depressed nonhuman primates."


Story Source:

The above story is based on materials provided by Elsevier. Note: Materials may be edited for content and length.


Journal Reference:

  1. Stephanie L. Willard, David R. Riddle, M. Elizabeth Forbes, Carol A. Shively. Cell Number and Neuropil Alterations in Subregions of the Anterior Hippocampus in a Female Monkey Model of Depression. Biological Psychiatry, 2013; 74 (12): 890 DOI: 10.1016/j.biopsych.2013.03.013

Cite This Page:

Elsevier. "Hippocampal volume loss in depression reflects glial loss." ScienceDaily. ScienceDaily, 17 December 2013. <www.sciencedaily.com/releases/2013/12/131217085219.htm>.
Elsevier. (2013, December 17). Hippocampal volume loss in depression reflects glial loss. ScienceDaily. Retrieved October 23, 2014 from www.sciencedaily.com/releases/2013/12/131217085219.htm
Elsevier. "Hippocampal volume loss in depression reflects glial loss." ScienceDaily. www.sciencedaily.com/releases/2013/12/131217085219.htm (accessed October 23, 2014).

Share This



More Mind & Brain News

Thursday, October 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Working Mother Getaway: Beaches Turks & Caicos

Working Mother Getaway: Beaches Turks & Caicos

Working Mother (Oct. 22, 2014) Feast your eyes on this gorgeous family-friendly resort. Video provided by Working Mother
Powered by NewsLook.com
What Your Favorite Color Says About You

What Your Favorite Color Says About You

Buzz60 (Oct. 22, 2014) We all have one color we love to wear, and believe it or not, your color preference may reveal some of your character traits. In celebration of National Color Day, Krystin Goodwin (@kyrstingoodwin) highlights what your favorite colors may say about you. Video provided by Buzz60
Powered by NewsLook.com
First-Of-Its-Kind Treatment Gives Man Ability To Walk Again

First-Of-Its-Kind Treatment Gives Man Ability To Walk Again

Newsy (Oct. 21, 2014) A medical team has for the first time given a man the ability to walk again after transplanting cells from his brain onto his severed spinal cord. Video provided by Newsy
Powered by NewsLook.com
Portable Breathalyzer Gets You Home Safely

Portable Breathalyzer Gets You Home Safely

Buzz60 (Oct. 21, 2014) Breeze, a portable breathalyzer, gets you home safely by instantly showing your blood alcohol content, and with one tap, lets you call an Uber, a cab or a friend from your contact list to pick you up. Sean Dowling (@SeanDowlingTV) has the details. Video provided by Buzz60
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins