Navigation Links
Misconnections in Developing Brain May Cause Autism

Mounting evidence opens possibility of future drug treatment, researchers say

MONDAY, Jan. 11 (HealthDay News) -- A new study adds to growing evidence that autism is caused by a miswiring of connections in a child's developing brain, resulting in impaired information flow.

According to researchers at Children's Hospital Boston, it may be possible to one day treat the problem with drugs that target the molecular pathways that cause the miswiring.

The study authors looked at a rare disorder called tuberous sclerosis complex (TSC), which causes benign tumors throughout the body, including the brain. Many people with TSC have epilepsy and intellectual disabilities, and about 25 percent to 50 percent of TSC patients have autism spectrum disorders.

In this study, the researchers found that mutations in one of TSC's causative genes (TSC2) prevent growing nerve fibers (axons) from locating their proper targets in the developing brain.

The team focused on a nerve fiber (axon) route between the eye's retina and the visual processing area of the brain in mice. When neurons were deficient in TSC2, their axons failed to end up in the correct locations. That's because the axons' tips, called growth cones, didn't respond to navigation cues from molecules called ephrins.

"Normally, ephrins cause growth cones to collapse in neurons, but in tuberous sclerosis the axons don't heed these repulsive cues, so keep growing," senior investigator Dr. Mustafa Sahin, of the hospital's neurology department, said in a news release.

This loss of axon responsiveness to ephrin signals is caused by activation of a molecular pathway called mTOR. The activity of this pathway increases when neurons are deficient in TSC2, the researchers noted.

This study examined retinal connections to the brain, but Sahin and colleagues said their findings may help improve general understanding of the organization of the developing brain. In autism, it's believed that abnormal wiring may occur in areas of the brain involved in social cognition.

"People have started to look at autism as a developmental disconnection syndrome -- there are either too many connections or too few connections between different parts of the brain," Sahin said in the hospital news release. "In the mouse models, we're seeing an exuberance of connections, consistent with the idea that autism may involve a sensory overload, and/or a lack of filtering of information."

The study was published online Jan. 10 in the journal Nature Neuroscience.

More information

The U.S. National Institute of Neurological Disorders and Stroke has more about autism.

-- Robert Preidt

SOURCE: Children's Hospital Boston, news release, Jan. 10, 2010

Copyright©2010 ScoutNews,LLC.
All rights reserved

Related medicine news :

1. NeoThrive(R) Enteral Feeding System Addresses the Serious Risk of Tubing Misconnections in NICU Facilities
2. AASM encourages those student-athletes at risk for developing osa to visit a sleep clinic
3. Pregnancy may increase the risk of developing binge eating disorder
4. Researcher developing new method for hearing loss assessment
5. Breastfeeding does not protect children against developing asthma or allergies
6. CEO Addresses Tennessee Business Leaders About Developing Pandemic and Business Continuity Plans
7. amfARs MSM Initiative Seeks Proposals From Front-Line Groups Working on HIV in Developing Countries
8. Developing a modular, nanoparticle drug delivery system
9. Jefferson scientists find protein may be key in developing deadly form of pancreatic cancer
10. AAAAI: Early Day Care Attendance May Protect Infants From Later Developing Asthma, From the Journal of Allergy and Clinical Immunology
11. IAEA and NFCR join forces to fight cancer in developing world
Post Your Comments:
(Date:11/29/2015)... ... , ... Khanna Vision Institute based in Los Angeles, announced that Dr. Khanna ... Peer Certification by the Board is done so the public knows that the Doctor ... after the completion of three years of training or Residency in Ophthalmology. This is ...
(Date:11/29/2015)... ... , ... Key Housing, a top-rated corporate housing service for the San Jose ... Epic. In showcasing this featured apartment community in San Jose, Key Housing is helping ... efficiently find housing suitable to their needs by showcasing quality housing. , “San Jose ...
(Date:11/28/2015)... ... 2015 , ... Pixel Film Studios is back again with ProPanel: Pulse ... are endless. Users have full control over angle of view, speed method, start point, ... sure to get heads to turn. , ProPanel: Pulse offers fully customizable pulsating shape ...
(Date:11/27/2015)... (PRWEB) , ... November 27, 2015 , ... ... affecting the health care in America. As people age, more care is needed, ... costs are rising, and medical professionals are being overworked. The forgotten part of ...
(Date:11/27/2015)... ... November 27, 2015 , ... ... 27th edition of USA Today in Atlanta, Dallas, New York, Minneapolis, South Florida, ... The digital component is distributed nationally, through a vast social media strategy and ...
Breaking Medicine News(10 mins):
(Date:11/26/2015)... , November 26, 2015 ... --> adds "Global Repaglinide ... "Investigation Report on China Repaglinide Market, ... forecasts data and information to its ... . --> ...
(Date:11/26/2015)... , Nov. 26, 2015 Research and ... of the "2016 Future Horizons and Growth ... Market: Supplier Shares, Country Segment Forecasts, Competitive Intelligence, ... --> --> ... of the Italian therapeutic drug monitoring market, including ...
(Date:11/26/2015)... DUBLIN , November 26, 2015 ... has announced the addition of the  ... in the European Cell Surface Marker ... Emerging Opportunities"  report to their offering.  ... announced the addition of the  "2016 ...
Breaking Medicine Technology: