|
L-Carnosine and Autism
by Jim English
L-Carnosine (Fig. 1) is a naturally occurring
amino acid found in high concentrations in muscle, heart and brain
tissues. L-Carnosine—not to be confused with the popular supplement,
L-carnitine—is a highly effective anti-aging nutrient that
possesses powerful antioxidant, free radical scavenging and neurotransmitter
properties. Carnosine inhibits the formation of carbonyl groups,
thereby reducing the formation of abnormal proteins. L-Carnosine
extends maximum cell division capacity, protects against DNA oxidation,
blocks glycosylation and reduces Advanced Glycation Endproducts
(AGEs), as well as acting as a cell membrane stabilizer and an intracellular
buffer (Fig. 2).
L-Carnosine is already a well-established anti-aging
nutrient that is used to treat liver disease, cataracts, Alzheimer's
disease, and cancer. L-Carnosine has recently been shown to possess
a tremendous potential for improving language and behavior in children
diagnosed with Autistic Spectrum Disorders (ASD).
Researchers treated 31 autistic children, ranging from 3 to 12 years
in age, with either 400 mg of L-Carnosine, twice a day, or a placebo,
for 8 weeks. At the end of the study the children treated with L-Carnosine
showed significant improvements in behavior, socialization, and
communication, as well as increases in language comprehension based
on CARS (Childhood Autism Rating Scale), vocabulary tests (E/ROWPVT)
and biweekly parent reports. In the conclusion to their report the
researchers state, "Oral supplementation with L-Carnosine resulted
in demonstrable improvements in autistic behaviors, as well as increases
in language comprehension that reached statistical significance."
In the Chez, et al study, the researchers report that L-Carnosine
may improve receptive language, auditory processing, socialization,
awareness of surroundings, and even help fine motor planning and
expressive language when compared to placebo. Responses are usually
seen between one to eight weeks after beginning treatment.
Based on his clinical experience in treating autistic spectrum disorders,
Dr. Chez recommends 400 mg of carnosine, twice daily, as an effective
dose. VRP's Carnosine is available in both 50 mg capsules (which
allows for smaller doses and greater parental control when titrating
to evaluate treatment effectiveness) and 500 mg capsules. L-Carnosine
can be given with or without food, and since it is tasteless capsules
may be opened to mix the white powder with foods and liquids. L-Carnosine
is well tolerated by diabetics and can be used with ketogenic and
gluten-casein free diets.
Anecdotal evidence suggests that some autistic children regress
in some of their language gains when treatment with L-Carnosine
was stopped. All children regained function when dosing was restarted.
Carnosine is considered an extremely non-toxic and safe substance.
As with other antioxidants, carnosine acts synergistically when
taken with other antioxidants. (For example, when vitamin E was
taken with carnosine, levels of both substances were higher in cardiac
muscle than when either was taken alone.)
Chez reports that manic or hyperactive autistic patients may show
signs of over stimulation, including increased irritability, hyperactivity,
or insomnia, when given higher doses of L-Carnosine. Symptoms usually
respond by decreasing either the dose of L-Carnosine or other medications
concurrently. No permanent negative physical changes have been noted
in over 1,000 children treated with L-Carnosine since June of 2001.
Furthermore, Chez reports no signs of adverse liver, blood, kidney,
or central nervous system side effects.
Double-Blind, placebo-controlled
study of L-carnosine supplementation in children with autistic
spectrum disorder
Michael G. Chez, M.D., Cathleen P. Buchanan,
Ph.D., Jamie L. Komen, M.A., Marina Becker, R.N.
L-Carnosine is an amino
acid dipeptide that may enhance frontal lobe function. We therefore
sought to investigate whether L-Carnosine supplementation for
children with Autistic Spectrum Disorders (ASD) results in observable,
objective changes in language and/or behavior in contrast to
placebo.
Thirty-one children
(21 M, mean age= 7.45; range = 3.2-12.5 yrs) meeting inclusion
criteria were enrolled in an 8 week blinded trial of either
400 mg BID powdered L-Carnosine or placebo. Children were assessed
at a pediatric neurology clinic with the Childhood Autism Rating
Scale (CARS), the Gilliam Autism Rating Scale (GARS), the Expressive
and Receptive One-Word Picture Vocabulary tests (E/ROWPVT),
and biweekly parental Clinical Global Impression of Change (CGI),
at baseline and 8 week endpoint.
Children on placebo (n=17)
did not show statistically significant changes on any of the
outcome measures. After 8 weeks on L-Carnosine, children (n=14)
showed statistically significant improvements on the GARS total
score, GARS Behavior, Socialization, and Communication subscales,
and the ROWPVT (all p's<.05).EOWPVT and CARS showed trends
in improvements, which were supported by parental CGI.
Oral supplementation
with L-Carnosine resulted in demonstrable improvements in autistic
behaviors as well as increases in language comprehension that
reached statistical significance. Although the mechanism of
action of the amino acid is not well understood, it is believed
that it acts to modulate neurotransmission and affect metal
ion transfer of zinc and copper in the entorhinal cortex. This
may enhance neurological function or act in a neuroprotective
fashion. |
|
