Saturday, April 19, 2014

Brain, Behavior, and Neuroscience Research in the News


All of these studies were published between April 16-18. Among the research presented below includes the following:
  • An article on how a hormone originally associated with appetite stimulation is now shown to accelerate synpase formation (along with being neuroprotective).
  • Two articles on how pervasive childhood issues (like shyness or being bullied) can be in a person's life.
  • Intravenous ketamine shows power in a trial involving people with PTSD.
  • New thinking is that Parkinson's Disease could be an autoimmune disorder.
  • In chronically depressed patients, increasing the depression-causing mechanisms actually instills resilience.
  • New research suggests connections between many neurodegenerative disorders.
  • Myelin has long thought to be centrally important in higher order brain cells, but new research suggests otherwise.
Enjoy!

Ghrelin accelerates synapse formation and activity development in cultured cortical networks

Irina I Stoyanova and Joost le Feber
Author Affiliations

BMC Neuroscience 2014, 15:49 doi:10.1186/1471-2202-15-49
Published: 17 April 2014


Abstract (provisional)


Background
While ghrelin was initially related to appetite stimulation and growth hormone secretion, it also has a neuroprotective effect in neurodegenerative diseases and regulates cognitive function. The cellular basis of those processes is related to synaptic efficacy and plasticity. Previous studies have shown that ghrelin not only stimulates synapse formation in cultured cortical neurons and hippocampal slices, but also alters some of the electrophysiological properties of neurons in the hypothalamus, amygdala and other subcortical areas. However, direct evidence for ghrelin's ability to modulate the activity in cortical neurons is not available yet. In this study, we investigated the effect of acylated ghrelin on the development of the activity level and activity patterns in cortical neurons, in relation to its effect on synaptogenesis. Additionally, we quantitatively evaluated the expression of the receptor for acylated ghrelin - growth hormone secretagogue receptor-1a (GHSR-1a) during development.

Results
We performed electrophysiology and immunohistochemistry on dissociated cortical cultures from neonates, treated chronically with acylated ghrelin. On average 76 +/- 4.6% of the cortical neurons expressed GHSR-1a. Synapse density was found to be much higher in ghrelin treated cultures than in controls across all age groups (1, 2 or 3 weeks). In all cultures (control and ghrelin treated), network activity gradually increased until it reached a maximum after approximately 3 weeks, followed by a slight decrease towards a plateau. During early developmental stages (1-2 weeks), the activity was much higher in ghrelin treated cultures and consequently, they reached the plateau value almost a week earlier than controls.

Conclusions
Acylated ghrelin leads to earlier network formation and activation in cultured cortical neuronal networks, the latter being a possibly consequence of accelerated synaptogenesis.

~ The complete article is available as a provisional PDF. The fully formatted PDF and HTML versions are in production.

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Inhibited children become anxious adults: Examining the causes and effects of early shyness

Date: April 17, 2014
Source: Penn State

Summary:
Three little girls sit together in a room, playing with the toys surrounding them. One of the girls -- "Emma" -- has clearly taken charge of the group, and the others happily go along with her. A fourth girl -- "Jane" -- enters the room, hiding her face while clinging to her mother. The first three continue to play, while mom sits Jane down with some toys a few feet away from the group. After mom leaves, however, Jane sits alone against the wall. Emma makes her way over to Jane, inviting her to play with the rest of the group. Jane -- looking trapped -- starts to cry, then stands up and tries desperately to open the door.

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Impact of childhood bullying still evident after 40 years

Date: April 17, 2014
Source: King's College London

Summary:
The negative social, physical and mental health effects of childhood bullying are still evident nearly 40 years later, according to new research. The study is the first to look at the effects of bullying beyond early adulthood. Just over a quarter of children in the study (28%) had been bullied occasionally, and 15% bullied frequently -- similar to rates in the UK today. Individuals who were bullied in childhood were more likely to have poorer physical and psychological health and cognitive functioning at age 50. Individuals who were frequently bullied in childhood were at an increased risk of depression, anxiety disorders, and suicidal thoughts.

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Intravenously administered ketamine shown to reduce symptoms of chronic post-traumatic stress disorder

Date: April 16, 2014
Source: Mount Sinai Medical Center

Summary:
For the first time, evidence that a single dose of IV-administered ketamine was associated with the rapid reduction of symptoms of post-traumatic stress disorder in patients with chronic PTSD was demonstrated in a proof-of-concept, randomized, double blind crossover study. These findings could be the first step toward developing new interventions for PTSD.

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Is Parkinson's an autoimmune disease?

Date: April 17, 2014
Source: Columbia University Medical Center

Summary:
The cause of neuronal death in Parkinson's disease is still unknown, but a new study proposes that neurons may be mistaken for foreign invaders and killed by the person's own immune system, similar to the way autoimmune diseases like type 1 diabetes, celiac disease, and multiple sclerosis attack the body's cells.

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Boosting depression-causing mechanisms in brain increases resilience, surprisingly

Date: April 17, 2014
Source: Mount Sinai Medical Center

Summary:
New research uncovers a conceptually novel approach to treating depression. Instead of dampening neuron firing found with stress-induced depression, researchers demonstrated for the first time that further activating these neurons opens a new avenue to mimic and promote natural resilience.

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Common links between neurodegenerative diseases identified

Date: April 17, 2014
Source: youris.com

Summary:
The pattern of brain alterations may be similar in several different neurodegenerative diseases, which opens the door to alternative therapeutic strategies to tackle these diseases, experts say.

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Finding turns neuroanatomy on its head

Posted On April 18, 2014


This is a computer image of three neurons showing differences in myelin.

Harvard neuroscientists have made a discovery that turns 160 years of neuroanatomy on its head.

Myelin, the electrical insulating material long known to be essential for the fast transmission of impulses along the axons of nerve cells, is not as ubiquitous as thought, according to a new work lead by Professor Paola Arlotta of the Harvard Stem Cell Institute (HSCI) and the University's Department of Stem Cell and Regenerative Biology, in collaboration with Professor Jeff Lichtman, of Harvard's Department of Molecular and Cellular Biology.

"Myelin is a relatively recent invention during evolution," says Arlotta. "It's thought that myelin allowed the brain to communicate really fast to the far reaches of the body, and that it has endowed the brain with the capacity to compute higher level functions." In fact, loss of myelin is a feature of a number of devastating diseases, including multiple sclerosis and schizophrenia.

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