Nav: Home

Ef­fects of rapid-act­ing an­ti­de­press­ants con­sol­id­ated in sleep?

April 22, 2020

Depression and long-term stress have been demonstrated to cause changes in the brain which offer a partial explanation for depressive moods, apathy, memory difficulties and other symptoms commonly associated with depression. Unbroken circles of negative thoughts are also often a distinct aspect of the mental status of depressed patients. This is down to very active and selective brain function.

"In turn, this strengthens the neural connections associated with precisely this type of thinking. Less active connections and neural networks supporting normal brain function weaken due to a lack of use, which completes the circle of negativity. The result is an imbalance of activity among neural networks, and clinical depression," says Associate Professor Tomi Rantamäki from the Faculty of Pharmacy, University of Helsinki.

The vicious circle could be broken by guiding the brain back towards a more comprehensive mode of action. Such guidance can be boosted by means of psychotherapy, but the effects manifest slowly. In recent years, rapid-acting modes of treatment for depression have been investigated, potentially offering entirely novel approaches. The latest new product is a nasal spray that contains esketamine, which was just granted a marketing authorisation in Europe.

"What ketamine, psychiatric electroconvulsive therapy, nitrous oxide and certain other therapies already in use or currently being trialled have in common is the fact that they increase the activity of broad cortical areas and strengthen synaptic connections. At their best, they force the broad neural networks of the cerebral cortex into an entirely new kind of interaction, which makes it possible to weaken the previous imbalance," notes Samuel Kohtala, a postdoctoral researcher at the University of Helsinki.

However, such rapid relief is only temporary, unless the plasticity mechanisms endogenous to the nervous system are utilised.

"According to the synaptic homeostasis hypothesis, synapses strengthened during the day undergo a process of renormalisation in deep sleep, which is dominated by slow-wave activity. The most potentiated synapses may retain their relative strength better than weaker synapses, which presents an opportunity for learning new information while purging the network of excessive noise. We think that rapid antidepressant treatments share the ability to regulate both synaptic potentiation and the reciprocal homeostatic mechanisms, which weaken synaptic strength during sleep. Either of these mechanisms can contribute to how the brain can reorganise its activity to defeat depression," Kohtala says.

Based on the studies, molecular mechanisms implicated in neuronal plasticity are particularly activated during periods of slow-wave activity. Thus, slow-wave responses could be a useful measure for determining treatment efficacy and developing novel treatments.

The researchers point out that, boosted by similar mechanisms, brain function may again be derailed during subsequent sleep periods, unless the neural networks driving the depression are sufficiently controlled, for example, by means of psychotherapy.

"The main symptoms of depression can be artificially affected by destabilising the functioning of neural networks. A more permanent effect requires tackling the root causes of the problem as well," Rantamäki emphasises.
-end-


University of Helsinki

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

Listen Again: The Power Of Spaces
How do spaces shape the human experience? In what ways do our rooms, homes, and buildings give us meaning and purpose? This hour, TED speakers explore the power of the spaces we make and inhabit. Guests include architect Michael Murphy, musician David Byrne, artist Es Devlin, and architect Siamak Hariri.
Now Playing: Science for the People

#576 Science Communication in Creative Places
When you think of science communication, you might think of TED talks or museum talks or video talks, or... people giving lectures. It's a lot of people talking. But there's more to sci comm than that. This week host Bethany Brookshire talks to three people who have looked at science communication in places you might not expect it. We'll speak with Mauna Dasari, a graduate student at Notre Dame, about making mammals into a March Madness match. We'll talk with Sarah Garner, director of the Pathologists Assistant Program at Tulane University School of Medicine, who takes pathology instruction out of...
Now Playing: Radiolab

What If?
There's plenty of speculation about what Donald Trump might do in the wake of the election. Would he dispute the results if he loses? Would he simply refuse to leave office, or even try to use the military to maintain control? Last summer, Rosa Brooks got together a team of experts and political operatives from both sides of the aisle to ask a slightly different question. Rather than arguing about whether he'd do those things, they dug into what exactly would happen if he did. Part war game part choose your own adventure, Rosa's Transition Integrity Project doesn't give us any predictions, and it isn't a referendum on Trump. Instead, it's a deeply illuminating stress test on our laws, our institutions, and on the commitment to democracy written into the constitution. This episode was reported by Bethel Habte, with help from Tracie Hunte, and produced by Bethel Habte. Jeremy Bloom provided original music. Support Radiolab by becoming a member today at Radiolab.org/donate.     You can read The Transition Integrity Project's report here.