Zebrafish study provides new insights into autism spectrum disorder research

January 24, 2018, Oregon State University

Exposure to a compound used to treat migraines and seizures causes characteristics associated with autism, groundbreaking research with zebrafish has demonstrated.

The study conducted by Oregon State University and Wenzhou Medical University showed valproic acid exposure resulted in phenotypes and behaviors consistent with , or ASD, and validated as a for studying ASD and its causes.

"The main thing we want to emphasize is the usefulness of this model," said co-author Courtney Roper, a postdoctoral fellow in OSU's College of Agricultural Sciences. "We can very quickly look at genetic and environmental factors associated with that are very difficult to understand in humans. The ease and speed of the genetic analysis in this model make it very attractive compared to a rodent model."

Autism spectrum disorder consists of five related neurodevelopmental disorders characterized by pervasive impairments in social interactions, deficits in verbal and nonverbal communication, repetitive patterns of behaviors and unusual sensitivity to sensory stimulation.

All of the factors behind autism are not known, but the etiology is known to have both genetic and environmental components, including prenatal exposure to two drugs: thalidomide, a sedative associated with severe birth defects, and valproic acid.

Autism diagnoses have been on the rise since the 1990s. According to the Centers for Disease Control, about one child in 68 will be identified with autism spectrum disorder.

ASD strikes all racial, ethnic and socioeconomic groups but is about 4.5 times more common among boys (1 in 42) than girls (1 in 189).

Zebrafish are a small freshwater species that go from a cell to a swimming fish in about five days. They reproduce rapidly and are particularly useful for studying the development and genetics of vertebrates, including the effects of environmental contaminants and pharmaceuticals on .

Zebrafish share a remarkable similarity to humans at the molecular, genetic and cellular levels, meaning many zebrafish findings are immediately relevant to humans. Embryonic zebrafish are of special interest because they develop quickly, are transparent and can be easily maintained in small amounts of water.

The OSU findings showed that treating zebrafish embryos with , or VPA, starting eight hours after fertilization led to a significant increase in the ASD macrocephalic phenotype - i.e., an enlarged head.

It also caused hyperactivity of movement behaviors in embryos and larvae, and a tendency toward ASD-like larval social behaviors.

"In addition to the ASD-like characteristics, we observed an overgrowth of mature newborn neurons and neural stem cells in the developing brain after VPA exposure," Roper said. "Next, now that we have models for behavior established, is to start looking at the genetic and environmental interactions, examining some of the potential factors that might be driving autism in humans."

Explore further: Autism therapy: Brain stimulation restores social behavior in mice

More information: Jiangfei Chen et al, Developmental and behavioral alterations in zebrafish embryonically exposed to valproic acid (VPA): An aquatic model for autism, Neurotoxicology and Teratology (2018). DOI: 10.1016/j.ntt.2018.01.002

Related Stories

Autism therapy: Brain stimulation restores social behavior in mice

December 13, 2017
Scientists are examining the feasibility of treating autistic children with neuromodulation after a new study showed social impairments can be corrected by brain stimulation.

Zebrafish model gives new insight on autism spectrum disorder

May 27, 2015
Autism Spectrum Disorder (ASD) is a neurological condition that affects approximately two percent of people around the world. Although several genes have been linked to multiple concurring conditions of ASD, the process that ...

Genetic body / brain connection identified in genomic region linked to autism

October 6, 2017
For the first time, Whitehead Institute scientists have documented a direct link between deletions in two genes—fam57ba and doc2a—in zebrafish and certain brain and body traits, such as seizures, hyperactivity, enlarged ...

Imbalances in neural pathways may contribute to repetitive behaviors in autism

April 17, 2017
Genetic studies have linked a number of risk genes to autism spectrum disorder (ASD). Although the complex genetics underlying ASD likely involve interactions between many genes, some risk genes are singular drivers of autism-like ...

Scientists make autism advance using monkey model

August 21, 2017
Autism is a common neurodevelopmental disorder characterized by impaired social communication and restricted and repetitive behavior or interests. The reported prevalence of autism has been rising worldwide. Due to the application ...

Estrogens alleviate hyperactivity in zebrafish with autism gene

January 28, 2016
Research led by UCL, Yale and University of California, San Francisco has shown that the hormone estrogen alleviates the sleep disruption experienced by zebrafish genetically designed to help understand the biology of autism ...

Recommended for you

Autism's social deficits are reversed by an anti-cancer drug

March 12, 2018
Of all the challenges that come with a diagnosis of autism spectrum disorder (ASD), the social difficulties are among the most devastating. Currently, there is no treatment for this primary symptom of ASD. New research at ...

Scientists link genes to brain anatomy in autism

February 27, 2018
A team of scientists at the University of Cambridge has discovered that specific genes are linked to individual differences in brain anatomy in autistic children.

Blood and urine tests developed to indicate autism in children

February 19, 2018
New tests which can indicate autism in children have been developed by researchers at the University of Warwick.

Autism might be better detected using new two-minute questionnaire

February 5, 2018
Researchers at Rutgers New Jersey Medical School have developed a two-minute questionnaire for parents that could help pediatricians and other primary care providers detect autism in toddlers, at a time when intervention ...

Research compares neural activity in children with and without autism spectrum disorder

January 29, 2018
Pick a hand, any hand. That familiar refrain, repeated in schoolyards the world over, is the basis of a simple guessing game that was recently adapted to study how and why kids with autism spectrum disorder (ASD) interact ...

Zebrafish study provides new insights into autism spectrum disorder research

January 24, 2018
Exposure to a compound used to treat migraines and seizures causes characteristics associated with autism, groundbreaking research with zebrafish has demonstrated.


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.