Author Interviews, Autism, Genetic Research / 23.02.2016
Regulation of microRNAs in the Brain May Be One Key to Autism Spectrum Disorders
MedicalResearch.com Interview with:
[caption id="attachment_21940" align="alignleft" width="213"]
Dr. Li Zeng[/caption]
Li ZENG, Ph.D.
Principal Investigator
Neural Stem Cell Research Lab
National Neuroscience Institute
Singapore
Medical Research: What is the background for this study? What are the main findings?
Dr. Zeng: Autism Spectrum Disorders (ASDs) are a group of highly inheritable behavioural disorders that pose major personal and public health concerns. Patients with ASDs have mild to severe communication difficulties, repetitive behaviour and social challenges. Such disorders significantly challenge an individual’s ability to conduct daily activities and function normally in society. Currently there are very few medication options that effectively treat ASDs. Therefore, there is a need to better understand the biology of that produces Autism Spectrum Disorder symptoms.
In the study, we found how one brain-specific microRNA (miR-128) plays a key role in causing abnormal brain development. MicroRNAs are small molecules that regulate gene expression in the human body to ensure proper cellular functions. Although it was known that miR-128 is misregulated in some patients with autism, what that meant and how it functioned was not known. We showed that miR-128 targets a protein called PCM1 that is critical to the cell division of neural precursor cells (NPCs). NPCs during early brain development have two fates - they either stay as NPCs and undergo self-renewal or become neurons through differentiation. The dysfunctional regulation of PCM1 by misregulated miR-128 impairs brain development, which may underlie brain size changes in people with Autism Spectrum Disorders.
Dr. Li Zeng[/caption]
Li ZENG, Ph.D.
Principal Investigator
Neural Stem Cell Research Lab
National Neuroscience Institute
Singapore
Medical Research: What is the background for this study? What are the main findings?
Dr. Zeng: Autism Spectrum Disorders (ASDs) are a group of highly inheritable behavioural disorders that pose major personal and public health concerns. Patients with ASDs have mild to severe communication difficulties, repetitive behaviour and social challenges. Such disorders significantly challenge an individual’s ability to conduct daily activities and function normally in society. Currently there are very few medication options that effectively treat ASDs. Therefore, there is a need to better understand the biology of that produces Autism Spectrum Disorder symptoms.
In the study, we found how one brain-specific microRNA (miR-128) plays a key role in causing abnormal brain development. MicroRNAs are small molecules that regulate gene expression in the human body to ensure proper cellular functions. Although it was known that miR-128 is misregulated in some patients with autism, what that meant and how it functioned was not known. We showed that miR-128 targets a protein called PCM1 that is critical to the cell division of neural precursor cells (NPCs). NPCs during early brain development have two fates - they either stay as NPCs and undergo self-renewal or become neurons through differentiation. The dysfunctional regulation of PCM1 by misregulated miR-128 impairs brain development, which may underlie brain size changes in people with Autism Spectrum Disorders.


Dr. Chugani[/caption]
MedicalResearch.com Interview with:
Diane C. Chugani, PhD
Director, Nemours Neuroscience Research
Nemours—AI DuPont Hospital for Children
Wilmington, DE 19803
Medical Research: What is the background for this study? What are the main findings?
Dr. Chugani: This clinical trial was performed at 5 sites throughout the country and was lead by our team at Wayne State University and Children’s Hospital of Michigan in Detroit. The study was sponsored by the National Institutes of Health through an Autism Centers of Excellence Network grant. Based upon our previous PET scanning studies showing low serotonin synthesis in the brains of young children with autism, we tested whether the serotonin-like drug buspirone would be beneficial in treating young children with Autism Spectrum Disorder. We found that low doses of buspirone were effective in reducing repetitive behaviors with no significant side effects in this group of children.
Dr. Kenworthy[/caption]
MedicalResearch.com Interview with:
Lauren Kenworthy, PhD
Associate professor of Neurology, Pediatrics, and Psychiatry
George Washington University School of Medicine
Director of the Center for Autism Spectrum Disorders
Children’s National Health System
Medical Research: What is the background for this study? What are the main findings?
Dr. Kenworthy: Connectivity among brain regions may account for variability in autism outcomes not explained by age or behavioral measures, according to a study. We have previously shown that behavioral assessments of intelligence, baseline adaptive behavior and executive functions in people with autism can explain some of the variation in outcomes and function, but we have not been able to explain all of the variance in outcome (e.g. Pugliese et al 2015a, 2015b).
In this study, we found that 44% of the study group experienced significant change in scores on adaptive behavior between the initial scan and follow-up. Connectivity between three resting-state networks, including the salience network, the default-mode network, and the frontoparietal task control network, was linked not only to future autistic behaviors but also to changes in autistic and adaptive behaviors over the post-scan period. Further, connectivity involving the salience network and associated brain regions was associated with improvement in adaptive behaviors, with 100% sensitivity and around 71% precision.
















