Suppression of 2', 3'-cyclic nucleotide 3'-phosphohydrolase activity in suckling rat brain by ACTH

A comparative study of high-dose and low-dose ACTH therapy for West syndrome

PURPOSE

A prospective randomized controlled study was conducted for the purpose of identifying the lowest effective ACTH dose, with the fewest adverse effects, for the treatment of West syndrome (WS).

SUBJECTS AND METHODS

Twenty-five subjects with cryptogenic (CWS, n = 9) or symptomatic (SWS, n = 16) WS were enrolled in this study. They were randomly assigned to receive either low-dose (0.005 mg/kg per day = 0.2 IU/kg per day) or high-dose (0.025 mg/kg per day = 1 IU/kg per day) synthetic ACTH therapy. ACTH was administered every morning for 2 weeks and tapered to zero over the subsequent 2 weeks. Both effectiveness and adverse effects were compared between the two treatment regimens in each type of WS.

RESULT

After completion of the treatment protocol in the CWS group, spasms and hypsarrhythmia were completely suppressed in 3/4 (75%) given the low-dose and 5/5 (100%) given the high-dose treatment. In the SWS group, the spasms and hypsarrhythmia disappeared in 6/8 (75%) in each dose group. There were no significant differences in initial responses between the low-dose and high-dose treatments for either type of WS (P > 0.05). Long-term seizure and developmental outcomes, assessed in the 17 responders who were followed up for longer than 1 year after the completion of ACTH therapy, were also essentially the same. We did not recognize differences in side effect profiles between the two treatment regimens with the exceptions of sleepiness and brain shrinkage estimated by CT scan, both of which were significantly milder in the low-dose than in the high-dose group (P < 0.05).

CONCLUSION

Unexpectedly, this prospective randomized controlled study demonstrated the dose of ACTH required for spasm cessation and disappearance of the hypsarrhythmic EEG pattern to be lower than previously believed. A low-dose regimen should thus be considered for CWS, and for SWS associated with significant cerebral atrophy.

Liposteroid (dexamethasone palmitate) therapy for West syndrome: a comparative study with ACTH therapy

Dexamethasone palmitate (liposteroid) was used for the treatment of West syndrome and compared with adrenocorticotropic hormone (ACTH) therapy. A single intravenous injection of liposteroid (0.25 mg/kg) was administered seven times in 3 months (total dosage = 1.75 mg/kg) to five symptomatic patients with West syndrome, aged 4-11 months. ACTH (0.025 mg/kg/day) was administered intramuscularly for 6 weeks according to the conventional therapy in Japan (total dosage = 0.625 mg/kg) to five symptomatic patients with West syndrome, aged 6-10 months. Nodding spasm and hypsarrhythmia on EEG disappeared in all patients in the liposteroid therapy group within four doses; however, partial seizures and focal spikes on EEG reappeared in three patients 2 months after the end of liposteroid therapy. In the ACTH therapy group, nodding spasm and hypsarrhythmia on EEG similarly disappeared during treatment in all patients, but nodding spasm reappeared 2 months after therapy in two patients and partial seizures reappeared in one patient 3 months after therapy. No notable adverse reactions occurred in the liposteroid group, but transient dysfunction of the thyroid and anterior pituitary gland and increased levels of serum cortisol were experienced in the ACTH group. These results suggest that glucocorticoid incorporated in a lipid emulsion is useful for the treatment of West syndrome.

Cortical hypometabolism and delayed myelination in West syndrome

PURPOSE

We examined the relation between cortical hypometabolism and delayed myelination in patients with West syndrome (WS).

METHODS

Serial positron emission tomography (PET) with [18F]fluorodeoxyglucose ([18F]FDG) and magnetic resonance imaging (MRI) were performed in 18 patients with WS, first at the onset of epileptic spasms and later at age 10 months. The age at onset of seizures ranged from 2 to 7 months. Ten patients were diagnosed as having cryptogenic WS and 8 as having symptomatic WS.

RESULTS

Cortical hypometabolism was detected in many patients at onset of epilepsy, but disappeared later, whereas delayed myelination tended to become evident with age. PET showed diffuse or focal cortical hypometabolism in 12 patients at onset, but in only 6 patients at age 10 months. MRI showed delayed myelination in only 2 patients at onset of epilepsy, but the number of patients with delayed myelination increased to 12 at age 10 months. Delayed myelination was more often present in patients with cortical hypometabolism. Delayed myelination was noted in 11 (85%) of 13 patients with cortical hypometabolism on first or second PET scans, but in only 1 (20%) of 5 patients who did not show PET abnormalities. Hypometabolism on the first or second PET scan was positively correlated with delayed myelination at age 10 months.

CONCLUSIONS

In patients with WS, assessing myelination with MRI again at age 8-10 months is important even when MRI at the onset of epilepsy appears normal. Serial MRI and PET scans disclose more detailed pathophysiology of WS.

Medical treatment of West syndrome in Japan

Although corticotropin (ACTH) is still the most effective drug for the treatment of West syndrome, a variety of other treatment modalities have been tried because of corticotropin's frequent and sometimes serious side effects. A recent survey on the treatment of this devastating disorder by Japanese child neurologists disclosed different therapeutic approaches from those taken by American or European child neurologists. Most Japanese child neurologists use vitamin B6 as the first agent and corticotropin as the third or second drug. Moreover, the dosage of corticotropin used by them is considerably smaller. Therefore, the current status of medical treatment of West syndrome is reviewed, especially comparing Japan with other countries.

Low levels of CSF gangliotetraose-series gangliosides in West syndrome: implication of brain maturation disturbance

One ml of cerebrospinal fluid (CSF) from each patient with West syndrome and patients from disease control groups were analyzed separately by highly sensitive thin-layer chromatography/enzyme-immunostaining method. The levels (mean +/- S.D.) of GM1, GD1a, sum of GD1b, GT1b, and GQ1b, and total gangliotetraose-series gangliosides in West syndrome patients (n = 14) and in an age-matched control group (n = 14) were as follows: 11.6 +/- 7.8 and 30.9 +/- 12.3 ng/ml CSF, 51.5 +/- 23.2 and 91.7 +/- 41.2 ng/ml CSF, 129.6 +/- 57.6 and 195.9 +/- 123.6 ng/ml CSF, and 192.7 +/- 78.6 and 318.4 +/- 131.6 ng/ml CSF, respectively. The differences were statistically significant except for the sum of GD1b, GT1b, and GQ1b (by 2 sample t test). Because they are abundant in the outer surface of neuronal plasma membranes, gangliosides may play an important role in the transformation of a neuroblast into a functionally mature neuron. Low levels of CSF gangliotetraose-series gangliosides, especially GM1 and GD1a, in patients with West syndrome may suggest a maturation disturbance of the brain from an early developmental stage.

Administration of ACTH to suckling rats results in hyperkinetic behavior

The present study on ACTH-administered suckling rats was undertaken to monitor the late behavioral sequelae due to the effects of this drug. The locomotor activity of rats treated with ACTH in the suckling period increased significantly as to the gross size of movements when compared with control rats. The increase in locomotor activity was correlated with the suppression of CNPase activity. These results show that administration of ACTH during the suckling period has suppressive effects on the development of the brain and behavior, and that these effects persist for a longer period after termination of the administration of ACTH than the direct effect of the peptide on endocrine functions.