Laser dissection of depression

Chinese investigators from Hefei and Dutch researchers in Amsterdam have collaborated using for the first time a combination of new elegant methodology in Depression research. They used postmortem human brain tissue that was donated to the Netherlands Brain Bank for research purposes and investigated a region in the basal part of the brain, the hypothalamus, that is known to be of crucial importance for the development of symptoms of depression.

This region is 6 mm³ large and is called the Paraventricular Nucleus (PVN) since it is situated along the third ventricle of the brain. This brain area is central in the regulations of our normal stress response, while a too high activity of the PVN is a pivotal characteristic of depression.

The hypothalamus consists of a large number of very small specialized cell groups that all have different functions and should thus be studied separately, hence the necessity of the application of the methodology used.

Corticotrophin-releasing factor (CRF) cells in the PVN of human hypothalamus are the central driving force of the stress response and are hyperactive in depression. The investigators sampled the PVN using new technology in psychiatry to study its molecular changes related to CRF.

Frozen hypothalami of 7 depressed patients and 7 controls of the same age, the same sex and obtained the same time after death. The frozen brain structures were serially sectioned and the PVN was dissected using a microscope with a laser beam. The micro-laser-dissected material was subsequently studied with a very sensitive and specific quantitative molecular technique for the analysis of gene expression (qPCR).

From the 16 gene products that were studied, because they were presumed to be involved in CRF activation in depression, 5 were found to show significant changes. The molecular changes found may not only explain the hyperactivity of the CRF cells but may also be potential targets for new therapeutic strategies.

Source: Molecular Psychiatry

Related stories:

Once a shy monkey, always a shy monkey? New study shows persistence of anxiety
We all know people who are tense and nervous and can't relax. They may have been wired differently since childhood.
Spiritual effects of hallucinogens persist, researchers report
In a follow-up to research showing that psilocybin, a substance contained in "sacred mushrooms," produces substantial spiritual effects, a Johns Hopkins team reports that those beneficial effects appear to last more than a year.
Migraine mutations reveal clues to biological basis of disorder
Fifteen percent to 20 percent of people worldwide suffer from migraines – excruciating headaches often presaged by dramatic sensations, or "auras." By studying a rare, inherited form of migraine, researchers at Vanderbilt University Medical Center have found clues to the biological basis of the painful, debilitating disorder.
Facebook concepts indicate brains of Alzheimer's patients aren't as networked
This is your brain on Facebook. Researchers at the Stanford University School of Medicine used concepts borrowed from the popular social networking site to analyze the brains of people with Alzheimer's disease. They found that patients' brains were less well-connected than the brains of people without the disorder.
Subtle nervous system abnormalities appear to predict risk of death in older individuals
Subtle but clinically detectable neurological abnormalities, such as reduced reflexes and an unstable posture, may be associated with the risk of death and stroke in otherwise healthy older adults, according to a report in the June 23 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.
Hunger hormone increases during stress, may have antidepressant effect
New research at UT Southwestern Medical Center may explain why some people who are stressed or depressed overeat. While levels of the so-called "hunger hormone" ghrelin are known to increase when a person doesn't eat, findings by UT Southwestern scientists suggest that the hormone might also help defend against symptoms of stress-induced depression and anxiety.
New research shows how aging brain brings a healthy dose of perspective
A University of Alberta researcher in collaboration with researchers from Duke University has proven that wisdom really does come with age, at least when it comes to your emotions.
Tsunami in the brain
After a stroke, even unaffected areas of the brain are at risk – depolarization waves arise at the edges of the dead tissue and spread through the adjacent areas of the brain. If these waves are repeated, more cells die. This has previously been observed only in animal studies.

News discussion:

Medicine & Health news