Fw: [asaphilly] Link Between Autism & Abnormal Blood-Vessel Function and Oxidative Stress

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[asaphilly] Link Between Autism & Abnormal Blood-Vessel Function and

Oxidative Stress

http://www.upenn.edu/almanac/volumes/v53/n32/rr.html

Research Roundup

May 1, 2007, Volume 53, No. 32

a.. Link Between Autism and Abnormal Blood-Vessel Function and Oxidative

Stress

Link Between Autism and Abnormal Blood-Vessel Function and Oxidative

Stress

Researchers at Penn’s School of Medicine discovered that children with

autism showed signs of abnormal blood-vessel function and damaging levels of

oxidative stress compared to healthy children. The children with autism

possessed levels of biochemicals that indicate the presence of constricted blood

vessels via the endothelium (the cells that line vessels) with a higher tendency

to form clots (through cells called platelets). Exploring the relationship

between oxidative stress and blood-vessel function in autistic patients, may

lead to new therapeutic options for this syndrome. The researchers, led by Dr.

Domenico Pratico, associate professor of pharmacology, published their findings

in the August issue of the Archives of Neurology.

According to the Autism Society of America, the reported number of autism

cases is increasing 10 to 17 percent per year in the U.S. Autism, an early onset

neurological disorder, is characterized by impaired social interactions, limited

verbal and nonverbal communication, and repetitive and restricted behavioral

patterns. Patients with autism can differ in the severity and scope of their

symptoms, suggesting that multiple factors contribute to explaining the

disorder’s symptoms. Previous studies at other institutions have shown that

autistic patients have reduced cerebral blood flow, presumably due to

constricted blood vessels in the brain, versus healthy controls.

Dr. Pratico’s team measured isoprostane, a biomarker for oxidative

stress; thromboxane, an index of platelet activation; and prostacyclin, a

measure of blood vessel activation in the samples. Compared with controls,

children with autism had significantly higher urinary levels of isoprostane,

thromboxone, and prostacyclin.

Oxidative stress is the result of an excessive formation of chemically

unstable byproducts, called free radicals, within the cell. Under normal

conditions, the cell is able to destroy the free radicals. However, when

excessive free radicals accumulate, these molecules mount an attack against the

cell in search of chemical stability.

Autism is a complex neurological disorder and oxidative imbalance is one

feature of the autistic syndrome. Several lines of evidence support the

hypothesis that oxidative imbalance may also play a role in this disease: autism

is characterized by an impaired anti-oxidant defense system, higher free-radical

production, and improvement of behavioral symptoms after taking anti-oxidants.