About My Health Careers Internship MedBlogs Contact us
Medindia LOGIN REGISTER
Advertisement

New Mechanism Reveals Possible Cause of Schizophrenia

by Julia Samuel on February 22, 2018 at 1:23 PM
Font : A-A+

New Mechanism Reveals Possible Cause of Schizophrenia

Elevated levels of a protein is associated with schizophrenia and other severe mental illnesses..

Protein neuregulin 3 controls how key neurotransmitters are released in the brain during schizophrenia. The protein is elevated in people with schizophrenia and other severe mental illnesses, but a recent study investigates how it causes such severe mental illness.

Advertisement


In a study published in the current issue of Proceedings of the National Academy of Sciences, neuroscientists from around the globe used genetic, electrophysiological, biochemical, and molecular techniques to uncover the function of neuregulin 3. They discovered it suppresses a protein complex required for proper neuron communication.

Certain variations in the gene encoding neuregulin 3 are considered risk factors for schizophrenia. The new study helps explain why neuregulin 3 is central to the disease. "We have identified a novel function of a schizophrenia susceptibility gene, neuregulin 3, which provides insight into cellular mechanisms of this devastating disorder and could lead to new therapeutic targets," said senior author Lin Mei, PhD.
Advertisement

Mei is professor and chair of the department of neurosciences at Case Western Reserve University School of Medicine. By understanding how neuregulin 3 acts in the brain, researchers could conceivably design drugs to restore its function during schizophrenia.

Schizophrenia affects nearly 1 in 100 American adults and is poorly understood, says Mei. It is difficult to tease apart the many interrelated proteins and neurotransmitters behind the disease. Mei's study outlines a previously unknown mechanism found in neurons affected by schizophrenia.

In the new study, researchers mutated the gene encoding neuregulin 3 in mice--but only in certain populations of neurons. When they mutated neuregulin 3 in neurons that help activate the brain--called pyramidal neurons--the genetically modified mice displayed behavior consistent with schizophrenia. They had healthy hearing and reflexes but were unusually active. They had trouble remembering and navigating mazes. In social interactions, the mice shied away from strangers. The experiments not only supported a role for neuregulin 3 in schizophrenia but also helped define types of neurons involved.

By studying brain samples from the mice, the researchers learned how neuregulin 3 works at the cellular level. They found it inhibits assembly of a complex of proteins at synapses, the place where adjacent nerve cells communicate. Neurons need the complex, called SNARE, to transmit certain neurotransmitters between each other.

In particular, SNARE complex helps neurons transmit glutamate--the most common "excitatory" neurotransmitter in the brain. Glutamate helps activate neurons and is essential for learning. Glutamate imbalances can cause schizophrenic symptoms.

People with severe mental illnesses like schizophrenia, bipolar disorder, and major depression, tend to have higher levels of neuregulin 3. The researchers mimicked protein levels found in the brains of schizophrenics by elevating neuregulin 3 in cultured neurons and found higher levels of neuregulin 3 suppresses glutamate release.

Cells with high levels of neuregulin 3 couldn't form SNARE complexes properly. Too much of the inhibitory protein prevented the complex from forming, and suppressed glutamate levels in the brain cells. The researchers concluded that neuregulin 3 is critical to proper glutamate transmission in the brain.

According to Mei, the findings are particularly intriguing because they show neuregulin 3 works differently than other proteins in its family. Neuregulin 1, for example, activates an entirely different set of proteins in other types of neurons. The mechanism Mei's team discovered for neuregulin 3 is even distinct from other roles previously described for the protein.

Said Mei, "In cancer biology, neuregulin 3 stimulates another risk gene of schizophrenia called ErbB4. Yet, unexpectedly, we found that neuregulin 3 in the brain may not act by activating ErbB4. Rather, it regulates glutamate release, and this novel function does not require ErbB4."

The findings suggest neuregulin 3 could serve as a new therapeutic target to help treat schizophrenia or other mental illnesses. Drugs that target neuregulin 3 could help restore glutamate levels in certain types of neurons--a novel approach to schizophrenia treatment.

"Identifying a novel mechanism of action is a prerequisite to understanding a disorder, and to development of therapeutic interventions," Mei said. "Of course, the road could be long to get there, but we are on our way."

Source: Eurekalert
Advertisement

Advertisement
News A-Z
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Advertisement
News Category
What's New on Medindia
Black Tea Protects against Blood Pressure and Heart Diseases
Green Mediterranean Diet may Help Repair Age-Related Brain Damages
Cervical Cancer Awareness Month 2022
View all

Medindia Newsletters Subscribe to our Free Newsletters!
Terms & Conditions and Privacy Policy.

More News on:
Schizophrenia Mental Health - Neurosis vs Psychosis Schizoaffective Disorder Mind-wandering Paranoia 

Recommended Reading
Schizophrenia
Schizophrenia is a mental disorder characterized by symptoms of thought, behavior and social ......
Commonly Used Food Preservative Enhances Schizophrenia Treatment
Sodium benzoate, when used as an add-on treatment was effective in those who are resistant to a ......
Digital Schizophrenia Pill With Sensor can Now Track Patients Taking the Medication
Abilify MyCite, a digital pill embedded with a sensor has been approved for use in patients ......
Gene Linked To Schizophrenia Risk Determines Early Brain Development
ZNF804A gene affects the structure and function of the brain during early fetal development leading ...
Mental Health - Neurosis vs Psychosis
Mental well-being is a concern and abnormal coping of emotions can lead to neurosis or psychosis. Me...
Mind-wandering
Mind wandering is a spontaneous and unintentional shifting of attention of thoughts from a primary t...
Paranoia
Paranoia is a false belief where the individual feels unfairly targeted or persecuted by everyone el...
Schizoaffective Disorder
Schizoaffective disorder is a serious mental disorder in which the individual reflects symptoms that...

Disclaimer - All information and content on this site are for information and educational purposes only. The information should not be used for either diagnosis or treatment or both for any health related problem or disease. Always seek the advice of a qualified physician for medical diagnosis and treatment. Full Disclaimer

© All Rights Reserved 1997 - 2022

This site uses cookies to deliver our services. By using our site, you acknowledge that you have read and understand our Cookie Policy, Privacy Policy, and our Terms of Use
open close
CONSULT A DOCTOR
I have read and I do accept terms of use - Telemedicine

Advantage Medindia: FREE subscription for 'Personalised Health & Wellness website with consultation' (Value Rs.300/-)