Autism Studies and Related Medical Conditions, January 2009 - TACA

Abstract: Service de Psychopathologie de l'Enfant et de l'Adolescent, Hopital Robert
Debre, Paris, France.
The effect of month-long naltrexone (NTX) treatment at a daily oral dose of 0.5
mg/kg/day was contrasted with placebo (PLC) in a double-blind study with conjoint
clinical and biochemical evaluations of therapeutic effects. Modest clinical benefits were
achieved with both PLC and NTX, with marginally better overall results following NTX,
and degree of improvement appeared to be related to plasma chemical profiles.
Massively elevated levels of beta-endorphin were observed in all children with assays
using C-terminal antibody but not with an N-terminal antibody assay. In addition, 70%
of the children exhibited abnormally low levels of adrenocorticotropic hormone, and
smaller subsets exhibited elevated norepinephrine (60%), arginine-vasopressin (50%),
and serotonin (20%). The best clinical responders exhibited the clearest normalization
of the elevated plasma chemistries, especially in C-terminal-beta-endorphin and
serotonin. There was some evidence of therapeutic carry-over effects in both clinical
and biochemical measures in those children who received NTX before PLC. The results
suggest that NTX only benefits a subgroup of autistic children, who may be identified by
the presence of certain plasma abnormalities. These results suggest a possible linkage
between abnormal plasma chemistries, especially those related to the proopiomelanocortin
system, and autistic symptoms.
Reichelt K.L. Knivsberg AM, Nodland M, Lind G: Nature and consequences of
hyperpeptiduria and bovine casomorphin found in autistic syndromes. Develop Brain
Dysfunct. 1994, 7: 71-85. [No abstract available]
Gardner M.L.G.: Absorption of intact proteins and peptides. Physiol of gastrointestinal
Tract 3rd edit (edit: LR Johnson) Raven press, New York 1994: 1795-1820.
Leboyer M, Bouvard MP, Launay JM, Recasens C, Plumet MH, Waller-Perotte
D, Tabuteau F, Bondoux D, Dugas M: Opiate hypothesis in infantile autism?
Therapeutic trials with naltrexone [Article in French]. Encephale 1993 Mar-
Apr;19(2):95-102.
Abstract: Service de Psychiatrie Adulte, Hopital Pitie-Salpetriere, Paris.
The opioid hypothesis suggests that childhood autism may result from excessive brain
opioid activity during neonatal period which may constitutionally inhibit social
motivation, yielding autistic isolation and aloofness (Panksepp, 1979). This hypothesis
has now received strong support and is currently based on three types of arguments:
(1) similarity between autistic symptomatology and abnormal behaviors induced in
young animals by injections of exogenous opioids, such as increasing social aloofness
and decreasing social vocalization; (2) direct biochemical evidence of abnormalities of
peripheral endogenous opioids being reported in autism and (3) therapeutic effects of
the long lasting opioid receptor blocking agent naltrexone in autism. In this article, we
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