beta-endorphin and Rett-Syndrome

In its typical form, Rett syndrome is characterized by the development, towards the end of the first year of life, of neurologic abnormalities in a formerly healthy girl. Our analysis of 13 observations of "classical" Rett syndrome shows that the most common findings include cognitive regression, autistic behavior, hypotonia, apraxia, and very suggestive stereotyped movements. Two other cases emphasize the problems raised by mild, atypical or incomplete forms. At present, there is no biological or morphological marker for this syndrome whose pathophysiology is unknown. Increased levels of beta-endorphins in the cerebrospinal fluid may prove to be a marker and suggests therapeutic possibilities.

Topics: beta-Endorphin; Biomarkers; Child; Child, Preschool; Female; Humans; Rett Syndrome

We measured CSF levels of beta-endorphin, an opioid hormone, in 19 patients with infantile autism and in 3 patients with Rett syndrome, and compared them with control values. In infantile autism, CSF levels of beta-endorphin did not differ significantly from those of age-matched controls. There was no significant correlation between CSF levels and clinical symptoms, including self-injurious behavior, pain insensitivity, and stereotyped movement. However, CSF levels of beta-endorphin were significantly higher in the patients with Rett syndrome than in the control (p < .05). Data suggest that neurons containing beta-endorphin may not be involved in patients with infantile autism. Thus, there is no relationship between dysfunction of brain opioid and autism.

Topics: Autistic Disorder; beta-Endorphin; Child; Female; Humans; Male; Matched-Pair Analysis; Neurons; Rett Syndrome; Self-Injurious Behavior; Stereotyped Behavior

The authors investigated whether there is excessive opioid activity in infantile autism by measuring plasma beta-endorphin in patients with autism compared with patients who had Rett's syndrome and normal comparison subjects.. Radioimmunoassays for beta-endorphin using C-terminally and N-terminally directed antisera were applied to plasma samples from 67 children who met both DSM-III-R and ICD-10 diagnostic criteria for infantile autism, 22 girls with Rett's syndrome, and 67 normal children matched in age and sex with the children with autism.. Median N-terminally directed beta-endorphin immunoreactivity appeared to be slightly lower in subjects with autism (7 pg/ml) and clearly higher in the girls with Rett's syndrome (40 pg/ml) than in the comparison subjects (9 pg/ml). Median C-terminally directed beta-endorphin immunoreactivity was higher in the girls with Rett's syndrome (35 pg/ml) and much higher in patients with autism (70 pg/ml) than in comparison subjects (8 pg/ml).. These findings demonstrate the existence of a wide discrepancy between C- and N-terminally directed beta-endorphin immunoreactivity among children with autism. Despite the fact that the nature of the antigen recognized in the plasma of autistic children by the C-terminally directed anti-beta-endorphin serum remains to be characterized, the difference between C- and N-terminally directed beta-endorphin immunoreactivity might suggest an abnormal processing of the pro-opiomelanocortin gene in infantile autism.

Topics: Adolescent; Adrenocorticotropic Hormone; Adult; Autistic Disorder; beta-Endorphin; Child; Child, Preschool; Dopamine; Dynorphins; Enkephalin, Leucine; Enkephalin, Methionine; Epinephrine; Female; Humans; Male; Norepinephrine; Opioid Peptides; Peptide Termination Factors; Pro-Opiomelanocortin; Radioimmunoassay; Rett Syndrome

To investigate pediatric brain impairment, beta-endorphin levels, one of the opioid peptides that modulate human high cortical functions, were measured in cerebrospinal fluid (CSF). The study included 19 patients with infantile autism, 3 patients with Rett syndrome, 6 patients with infantile spasms, 16 patients with aseptic meningitis, and 23 age-matched controls. In the control group, the CSF beta-endorphin concentrations were negatively correlated with increasing age. There was no correlation between body temperature and the levels, and no significant difference in the levels according to sex. In infantile autism, the CSF level was not significantly different from that in controls. In Rett syndrome, it was significantly higher, while in infantile spasms it was lower than in controls. In aseptic meningitis, the CSF beta-endorphin level was significantly higher than in controls. The alterations in CSF beta-endorphin levels may play a role in these neurologic disorders and/or in central nervous system (CNS) infections.

Topics: Autistic Disorder; beta-Endorphin; Child; Child, Preschool; Female; Humans; Infant; Infant, Newborn; Male; Meningitis, Aseptic; Rett Syndrome; Spasms, Infantile

Because some symptoms of Rett's syndrome are suggestive of excessive endogenous opioid activity, we measured the levels of beta-endorphin-like immunoreactivity in lumbar CSF from 158 affected female patients and from 13 female controls. The mean (+/- SE) control level of beta-endorphin immunoreactivity in CSF was 35.3 +/- 2.8 pg/ml (range, 23 to 48 pg/ml), whereas those with Rett's syndrome had a mean level of 95.3 +/- 3.6 pg/ml (range, 31 to 293 pg/ml). The levels of beta-endorphin immunoreactivity in initial CSF samples exceeded the control range in 90% of the patients with Rett's syndrome. The mean beta-endorphin immunoreactivity was also elevated in CSF from leukemic children (119.2 +/- 16.9 pg/ml; range, 40 to 159 pg/ml), relative to the control group. These results are consistent with the hypothesis that some symptoms of Rett's syndrome may be associated with excessive endogenous opioid levels in the CNS.

Topics: Adolescent; Adult; beta-Endorphin; Child; Child, Preschool; Female; Humans; Leukemia; Male; Radioimmunoassay; Rett Syndrome

An evaluation of cerebrospinal fluid and plasma beta-endorphin and cortisol levels was performed in 15 girls affected with classic Rett syndrome. There were no differences between the patient group and the control group in plasma cortisol and beta-endorphin levels. But in Rett syndrome, a significant increase in beta-endorphin was noted in the cerebrospinal fluid, with an elevation of the cerebrospinal fluid/plasma beta-endorphin ratio and a decrease in cerebrospinal fluid cortisol. A substantial overlap between patients and control group diminishes the diagnostic value of cerebrospinal fluid beta-endorphin assay in girls suspected of having Rett syndrome.

Topics: Adolescent; Adult; beta-Endorphin; Child; Child, Preschool; Female; Humans; Hydrocortisone; Rett Syndrome

An hypothesis of increased endorphinergic activity has been proposed to account for the characteristic symptoms of Rett syndrome. Cerebrospinal fluid samples from eight girls with Rett syndrome were analysed for beta-endorphin (beta-EP) immunoactivity and compared with samples from a control group of 15 children with acute leukaemia in remission. Severity of symptoms was not found to be related to beta-EP level. A group of early-treated adolescents with phenylketonuria had beta-EP levels similar to the Rett syndrome patients, but no symptoms resembling theirs. Therefore it is unlikely that increased levels of beta-EP are of primary pathogenetic significance. The conflicting findings of many earlier reports may be a result of differences between control groups.

Topics: Adolescent; beta-Endorphin; Child; Female; Humans; Leukemia; Male; Neurologic Examination; Phenylketonurias; Reference Values; Rett Syndrome