Faulty serotonin--DHEA interactions in autism: results of the 5-hydroxytryptophan challenge test.
BACKGROUND
Autism is accompanied by peripheral and central disorders in the metabolism of serotonin (5-HT). The present study examines plasma dehydroepiandrosterone-sulphate (DHEA-S) and the cortisol/DHEA-S ratio following administration of L-5-hydroxytryptophan (5-HTP), the direct precursor of 5-HT, to autistic patients.


METHODS
Plasma DHEA-S levels were determined both before and after administration of 5-HTP or placebo, on two consecutive days in a single blind order in 18 male autistic patients and 22 matched healthy controls.


RESULTS
The 5-HTP-induced DHEA-S responses were significantly higher in autistic patients than in controls. In baseline conditions, the cortisol/DHEA-S ratio was significantly higher in autistic patients than in controls.


CONCLUSIONS
The results suggest that autism is accompanied by a major disequilibrium in the serotonergic system. The increased Cortisol (neurotoxic) versus DHEA-S (neuroprotective) ratio suggests that an increased neurotoxic potential occurs in autism.


CONCLUSIONS
It is concluded that a disequilibrium in the peripheral and central turnover of serotonin and an increased neurotoxic capacity by glucocorticoids are important pathways in autism.
Croonenberghs
Jan
J
University Center of Child and Adolescent Psychiatry, A.Z. Middelheim, Faculty of Medicine, University of Antwerp, Wilrijk, Belgium. jan.croonenberghs@zna.be
Spaas
Kristien
K
Wauters
Annick
A
Verkerk
Robert
R
Scharpe
Simon
S
Deboutte
Dirk
D
Maes
Michael
M
D006916:5-Hydroxytryptophan; D000293:Adolescent; D000704:Analysis of Variance; D001321:Autistic Disorder / Q000097:blood* / Q000175:diagnosis*; D019314:Dehydroepiandrosterone Sulfate / Q000097:blood*; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D008297:Male; D011569:Psychiatric Status Rating Scales; D012701:Serotonin / Q000097:blood*; D016037:Single-Blind Method
D012701:Serotonin; D019314:Dehydroepiandrosterone Sulfate; D006916:5-Hydroxytryptophan; D006854:Hydrocortisone