Summary: A new study has identified a brain protein, vesicular nucleotide transporter ( Vnut ), as essential for regulating mood and motivation in mice. When Vnut was removed from brain cells called astrocytes, the animals displayed higher stress, depression-like behaviour, and decreased desire, particularly in women.
Reduced serotonin, a crucial molecule for inspiration and good mood, was linked to this effect. These findings point to a crucial responsibility that Vnut plays in dopamine legislation, which could help us understand mood disorders.
Important Information:
- In animals, removing Vnut from astrocytes caused panic and depressive behavior.
- Adult mice lacking Vnut had noticeably less motivation for rewards, a symptom associated with depression.
- The results were linked to lower serotonin levels, important for motivation and mental regulation.
Origin: University of Kentucky
A team led by researchers at the University of Kentucky was working on the identification of a crucial proteins in the brain that controls animals ‘ motivation for compensation.
The research, titled” Deletion of murine astrocytic intracellular genetic carrier raises anxiety and depressive-like behaviour and attenuates , motivation , for reward”, was published in , Molecular Psychiatry.
Through a variety of mechanisms, this research examines the significant regulators of mental activity. Finally, understanding this better could lead to innovative solutions for neurological and psychiatric problems”, said Weikang Cai, Ph. Dr., a professor in the Barnstable Brown Diabetes and Obesity Research Center ( BBDOC ) and an associate professor in the College of Medicine’s Department of Molecular and Cellular Biochemistry.
Cai is also the lead analyst of a grant that the National Institute of Mental Health awarded as a result of this job. He worked with Qian Huang, Ph. primary author of this paper, D., a research associate professor in the department of Molecular and Cellular Biochemistry.
The research team’s focus was on astrocytes, a type of mental body that supports the central nervous system. These tissues are known to release substances to converse with neurons, which are essential for proper brain function.
For instance, a protein called vesicular nucleotide transporter ( Vnut ) mediates the release of specific molecules, ATP, which usually provide energy to cells. Researchers were interested in finding out if the ATP released via Vnut is crucial for any mental performance.
To evaluate the practical significance of Vnut, experts removed this proteins from the astrocytes in their , rat model , and finally analyzed the , mice’s conduct. This protein termination, according to experts, did not alter mind structure, respiration, or memory.
Through open area checks and a prize test, the group also examined the loss of Vnut in the mice’s anxiety and depression-like actions.
” We found the loss of Vnut in adult animals led to increased stress, depressive-like activities and, more important, decreased desire for reward, especially in ladies”, said Cai.
Researchers found that adult mice spent most of their time against the walls in empty field experiments rather than the open area, which suggests that they had an anxious disposition.
According to Huang,” The current research shows that mice can produce depressive-like behavior when their astrocytes lose Vnut.” The exact mechanisms that govern despair in humans could be at play here.
Scientists noticed changes to the mice’s social variables, most notably a lack of attention and an increased paralysis during swimming tests.
Finally, the study group taught their mice to push a system with their nostril to get food pellets that contain sucrose when determining motivation for reward. Typical mice will get a strong incentive from the sweetened meals pellets.
Regular females continued to work for the prize pellets even when the work issues increased or when more pokes were required to get the meal. In stark comparison, females who lack Vnut tend to give up on the work more quickly, which means they have less of a desire for the reward, which is frequently a scientific sign for major depression in humans.
Interestingly, Cai’s research team pinpointed the decreased motivation for reward to the decreased level of dopamine, a “happy” molecule in the brain essential for inspiring behavior in both rodents and humans.
The findings from this study suggest that Vnut is a , important protein , in the regulation of serotonin signals in the head, feeling and enthusiasm, reduction of which results in functional consequences including panic, depressive-like habits and a reduction in the motivation for reward.
” This discovery helps us understand how specific proteins in certain , brain regions , influence emotions and , behavior, providing new approaches for future research about , mood disorders”, said Cai.
About this news about neuroscience research
Author: Sara Macias Palacio
Source: University of Kentucky
Contact: Sara Macias Palacio – University of Kentucky
Image: The image is credited to Neuroscience News
Original Research: Closed access.
Qian Huang and colleagues ‘ study,” Murine astrocytic vesicular nucleotide transporter deletion increases anxiety and depressive behavior and attenuates motivation for reward.” Molecular Psychiatry
Abstract
The murine astrocytic vesicular nucleotide transporter is removed, which causes anxiety and depressive behavior, and lessens motivation for reward.
Astrocytes are multi-functional glial cells in the central nervous system that have important roles in controlling metabolism, extracellular ion and neurotransmitter levels, and synaptic plasticity.
Astrocyte-derived signaling molecules mediate many of these modulatory functions of astrocytes, including vesicular release of ATP. We investigated the functional significance of astrocytic exocytosis of ATP using a novel genetic mouse model in this study.
We demonstrate that the loss of the vesicular nucleotide transporter ( Vnut ), a primary transporter responsible for the secretory vesicles, dramatically reduces ATP loading into secretory lysosomes and ATP release, without any alteration in the molecular machinery of exocytosis or total intracellular ATP content.
Deletion of astrocytic Vnut in adult mice leads to increased anxiety, depressive-like behaviors, and decreased motivation for reward, especially in females, without significant impact on food intake, systemic glucose metabolism, cognition, or sociability.
These behavioral changes are linked to significant decreases in the nucleus accumbens ‘ basal extracellular dopamine levels. Ex vivo brain slices from these mice also exhibit a clear trend toward a decrease in the nucleus accumbens’ evoked dopamine release.
Mechanistically, the reduced dopamine signaling we observed is likely due to an increased expression of monoamine oxidases.
Together, these data demonstrate a key modulatory role of astrocytic exocytosis of ATP in anxiety, depressive-like behavior, and motivation for reward, by regulating the mesolimbic dopamine circuitry.
