Homovanillic acid and 5-hydroxyindoleacetic acid levels in cerebrospinal fluid of patients with progressive myoclonus epilepsy

The possibility of disturbed dopamine and serotonin metabolism in the progressive myoclonus epilepsy (PME) occurring in Finland (a type of PME without Lafora bodies) was examined. Both basal concentrations of HVA and 5-HIAA in the CSF and their increase after oral probenecid administration were studied in 19 PME patients and in 19 age- and sex-matched control patients. The control patients had grand mal epilepsy but not myoclonus or ataxia. The basal value of HVA was significantly reduced and that of 5-HIAA was also slightly reduced in the PME patients as compared to the values of the epileptic controls or to those of 26 nonepileptic controls. The concentrations of HVA and 5-HIAA also seemed to correlate with the severity of the PME. The most severely affected patients had generally the lowest values. After oral probenecid this trend was also seen when the increases of HVA and 5-HIAA were expressed per microgram CSF probenecid, i.e. the mildly affected PME group showed higher increases in response to probenecid than the most severely affected PME group. The PME patients had higher probenecid levels in the CSF than the epileptic controls.     

Common dopaminergic mechanism for epileptic photosensitivity in progressive myoclonus epilepsies

We studied the effect of apomorphine, a dopamine receptor agonist, on epileptic photosensitivity in 7 patients with progressive myoclonus epilepsy (PME). Specific diagnoses included Baltic PME (Unverricht-Lundborg disease), Lafora disease, Kufs' disease, juvenile neuroaxonal dystrophy, and action myoclonus-renal failure syndrome; 2 patients had PME of uncertain etiology. Apomorphine blocked the epileptic photosensitivity in all patients and also reduced intention myoclonus in a patient with Baltic PME. There is a common deficit of dopaminergic inhibitory neurotransmission at the level of the striate cortex in patients with PME, regardless of the nature of the specific underlying neuropathologic process.     

Treatment of myoclonus with l-5-hydroxytryptophan and carbidopa: Clinical,electrophusiological, and biochemical observations

Six patients with myoclonus of varying cause were treated with L-5-hydroxytryptophan (L-5-HTP) and carbidopa. While spontaneous myoclonus decreased in three of the patients and action myoclonus in four, only two patients had marked functional improvement. Side effects included gastrointestinal and affective disturbances. L-5-HTP therapy caused a diminished frequency of paroxysmal discharges in the electroencephalograms of three patients which did not always correlate with clinical improvement. Lumbar cerebrospinal fluid 5-hydroxyindoleacetic acid (5-HIAA) concentration after probenecid was decreased in all patients prior to therapy, but this reduction did not predict treatment response. Urinary excretion patterns for 5-HTP, serotonin, and 5-HIAA during treatment were similar in responders and nonresponders. It is concluded that while some patients with myoclonus do benefit from L-5-HTP therapy, biochemical and electrophysilogical tests are not useful predictors of treatment response, and the high incidence of side effects limits the usefulness of this therapy.     

L-tryptophan-carbidopa trial in patients with long-standing progressive myoclonus epilepsy

Eleven patients with long-standing progressive myoclonus epilepsy, PME, and age- and sex-matched epileptic controls received L-tryptophan (L-Trp) 100 mg/kg body weight combined with carbidopa in addition to their usual anticonvulsant regimen. During six weeks of the trial an improvement in activities of daily living and a decrease of action myoclonus was noted in the PME patients. The frequency of seizures compared with the past year decreased significantly in the PME patients, but not in the epileptic controls. Changes in the EEGs of the PME patients were scant, but a slight decrease was noted in myoclonic spikes. Both plasma Trp and platelet 5-HT increased significantly and at least as much as in epileptic controls. 5-HIAA and HVA concentrations in the CSF of the PME patients increased significantly during the trial. The results support previous findings concerning Trp treatment in PME, and longer trials with Trp + carbidopa could be of value in this disease.     

Estradiol and progesterone influence a serotonin mediated behavioral syndrome (myoclonus) in female guinea pigs: Comparison with steroid effects on reproductive behavior

L-5-hydroxytryptophan (L-5-HTP)-induced myoclonus was used as a behavioral index of central serotonergic activity. Estradiol benzoate (EB) and progesterone (P) influenced the induction of myoclonus by L-5-HTP. When L-5-HTP was injected 46 h after EB, myoclonus was enhanced. P blocked this effect on EB when 100 or 125 mg/kg L-5-HTP (but not 80 mg/kg) was given 6 h after P in EB-primed animals. When L-5-HTP was given 3 or 11-15 h after P in EB-primed animals, there was no inhibitory effect of P on myoclonus. In fact, at the lowest dose (80 mg/kg), L-5-HTP increased myoclonus when given 3 h after P in EB-primed animals. The inhibitory effects of P in EB-primed females on myoclonus were temporally correlated with the display of lordosis, suggesting that the neural progestin receptor mechanisms that have been proposed to mediate P effects on lordosis are also involved in the inhibitory effects of P on myoclonus.     

Decrease of GABA in the cerebrospinal fluid of patients with progressive myoclonus epilepsy and its correlation with the decrease of 5HIAA and HVA

The degenerative type of progressive myoclonus epilepsy (PME) is a hereditary disease with grand mal seizures, stimulus sensitive myoclonus, characteristic EEG and mental deterioration in the late stage. GABAergic antiepileptic drugs are the most effective ones in this disease, with an unknown etiology. In this study, the GABA concentration in the CSF of 15 PME patients was measured and compared with values of sex- and age-matched epileptic controls. It was correlated with the concentrations of 5HIAA and HVA in the CSF, which were determined earlier from the same patients. The GABA concentration in the PME patients was statistically significantly decreased, to about 75% of that of the epileptic controls. It correlated with HVA and 5HIAA concentrations in the PME patients, but not in the epileptic controls. It is unknown whether these findings are related to the primary cause of PME or whether they are only secondary, owing to a loss of respective neurons or synapses.     

Deficient intestinal absorption of l-tryptophan in progressive myoclonus epilepsy without Lafora bodies

l-Tryptophan was administered orally to 7 patients with progressive myoclonus epilepsy (PME) without Lafora bodies and 7 controls. Total and free plasma tryptophan were subsequently measured at intervals. Concentration of free tryptophan was equal in the two groups. Total tryptophan was significantly lower in PME patients and the difference became marked at 120 and 240 min after the oral dose. At the same time urinary excretion of indican rose in PME patients but not in controls but the change was not statistically significant. Urinary 5-HIAA excretion was a little lower in PME patients. The increase of 5-HIAA after administration of l-tryptophan was equal in both groups. Intravenous administration of l-tryptophan produced an equal increase of plasma concentrations in PME patients as in controls, measured at 2-h intervals. These findings suggest incomplete absorption of l-tryptophan through the intestinal tract in PME patients.     

Clinical, biochemical, and pharmacological observation in a patient with postasphyxic myoclonus: association to serotonin hyperactivity

Posthypoxic action myoclonus is usually associated with impaired serotonin (5-HT) neurotransmission but in some patients 5-HT precursors aggravate and 5-HT blockers improve action myoclonus. We studied a 65-year-old man who presented with action myoclonus following a prolonged episode of moderate hypoxia and severe hypercarbia. The myoclonus increased with 5-hydroxytryptophan (5-HTP) 1,200 mg/day plus carbidopa 300 mg/day and sodium salt of valproic acid (SVA) 800 mg/day, and improved with 1 mg of clonazepam (CNZ) in an intravenous bolus. Biochemical analysis of the cerebrospinal fluid (CSF) prior to any drug therapy did not reveal abnormalities in the levels of homovanillic acid (HVA) and methoxyhydroxyphenylglycol (MHPG) but 5-hydroxyindoleacetic acid (5-HIAA) levels were elevated in comparison with controls (33 versus 21 ng/ml). SVA therapy produced a moderate increase and 5-HTP plus carbidopa a threefold elevation of 5-HIAA in CSF and marked aggravation of action myoclonus. Methysergide (3 mg/day) totally suppressed myoclonus and decreased CSF 5-HIAA to undetectable levels. Methysergide also reduced CSF tryptophan to 40% of baseline levels. Discontinuation of methysergide and substitution by placebo was followed by reappearance of myoclonus. A partial and incomplete spontaneous remission of symptoms took place 7 months after the asphyxic episode. Action myoclonus and enhanced 5-HT neurotransmission may be present in patients in which acidosis reverses the effects of hypoxia on 5-HT neurotransmission.     

Treatment of myoclonic syndromes with paroxetine alone or combined with 5-HTP

Paroxetine is a specific presynaptic 5-hydroxytryptamine (5-HT) reuptake inhibitor which ameliorated posthypoxic intention myoclonus in 2 out of 3 patients, when given alone or in combination with L-5-hydroxytryptophan (5-HTP) with carbidopa. The concentration of 5-HT in the cerebrospinal fluid from 1 patient was only 3 nmol/l despite the presence of 600 nmol/l of 5-HTP during steady state treatment with the amino acid and paroxetine. No effect of the combined medication was found in 2 patients disordered by palatal myoclonus.     

Movement-activated myoclonus in genetically defined progressive myoclonic epilepsies: EEG-EMG relationship estimated using autoregressive models.

OBJECTIVE: To study electroencephalography-electromyography (EEG-EMG) relationships in patients with different forms of progressive myoclonic epilepsies (PME). METHODS: EEG-EMG auto-spectra, coherence and phase functions were estimated by means of bivariate and time varying autoregressive (AR) models in 15 patients: 8 with Unverricht-Lundborg, 4 with Lafora body disease, and 3 with sialidosis. RESULTS: The coherence spectra of the EMG epochs including action myoclonus and contralateral frontocentral EEG derivations showed a main beta peak (average coherence: 0.60-0.79) in all patients, regardless of the type of PME. The time lag from cortex to muscle was 13.0-21.3 ms. Significantly, coherent gamma activity was consistently found only in the 3 patients with sialidosis; the most heterogeneous results were obtained in the patients with Lafora disease, who showed a more complex coherence profile. Periods of normal muscle contractions, which could be recorded in patients with Unverricht-Lundborg PME, were characterised by the presence of an EEG-EMG beta coherence peak on the same frequency as in the case of action myoclonus, but with a lower coherence value. CONCLUSIONS: AR models were capable of describing EEG-EMG relationships in patients with PME, and indicated that coherent cortical and EMG beta oscillations are crucially involved in the generation of myoclonus. Moreover, they could detect the uneven spectral profiles characterising the different forms of PME.     

Open trial with levodopa-carbidopa combination to patients with long-standing progressive myoclonus epilepsy

Six adult patients with long-standing progressive myoclonus epilepsy (PME) received levodopa combined with carbidopa in addition to their usual anticonvulsant regimen. During 5 weeks of treatment an improvement in daily activities and a decrease of action myoclonus were observed. The spontaneous EEG did not differ from the recordings prior to the trial, but the provoked EEG showed fewer reactions during provocations in 5 out of 6 patients. The treatment had no effect on psycho-motor reaction time or epileptic seizures. Pre-trial HVA values in the CSF of the PME patients were significantly lower than those of their epileptic controls, but during the trial CSF HVA values in PME patients increased markedly. No untoward side-effects were noted. The results suggest that there could be an alteration of dopaminergic tone in PME.     

Estradiol and progesterone influencel-5-hydroxytryptophan-induced myoclonus in male guinea pigs: Sex differences in serotonin-steroid interactions

The effects of castration in males and sex differences in the effects of estradiol and progesterone on L-5-hydroxytryptophan (L-5-HTP)-induced myoclonus in guinea pigs were examined. Castration had no effect on L-5-HTP-induced myoclonus in males. There were sex differences in sensitivity to L-5-HTP. In the absence of steroids, L-5-HTP-induced myoclonus was higher in gonadectomized males than females. A low dose of estradiol benzoate (EB; 3.5 micrograms) given 46 h before L-5-HTP (100 mg/kg) enhanced myoclonus in gonadectomized females but not males. However, at a higher dose of EB (10 micrograms) and a lower dose of L-5-HTP (80 mg/kg), myoclonic responding was enhanced in males. These findings indicate that estradiol has a similar effect on L-5-HTP-induced myoclonus in males and females, but do not rule out the possibility of sex differences in sensitivity to L-5-HTP when both sexes are given estradiol priming. When L-5-HTP was given 6 h after 0.5 mg progesterone in estradiol-primed males, myoclonus was enhanced. Progesterone treatment reverses the facilitative effect of EB on L-5-HTP-induced myoclonus in females. Therefore, progesterone has opposite effects on L-5-HTP-induced myoclonus in males and females. These findings were discussed with respect to the interaction of steroids and 5-HT transmission in the regulation of steroid-dependent reproductive behavior.     

Indole levels in human lumbar and ventricular cerebrospinal fluid and the effect of L-tryptophan administration

Levels of tryptophan (TRP), 5-hydroxytryptophan (5-HTP), 5-hydroxytryptamine (5-HT), and 5-hydroxyindoleacetic acid (5-HIAA) in human lumbar and ventricular cerebrospinal fluid (CSF) were measured by reversed phase liquid chromatography (HPLC) with electrochemical detection. The levels of TRP ranged from 1593 to 4865 nmol/l in ventricular (VF) and from 1257 to 2557 nmol/l in lumbar CSF. The level of 5-HTP varied from 1.1 to 68.9 nmol/l in VF and from 5.3 to 10.8 nmol/l in lumbar CSF; no previous reports of 5-HTP levels in CSF exist. The serotonin level was 1.9-27.3 nmol/l in VF and 5.7-12.0 nmol/l in lumbar CSF. The levels of 5-HIAA were considerably higher in VF than in lumbar fluid with respective means of 498 +/- 52.4 nmol/l and 112 +/- 15.6 nmol/l (P less than 0.001). An oral dose of 2 g L-tryptophan significantly increased all indole levels except that of 5-HT, both in patients with progressive myoclonus epilepsy and in controls.     

CSF oligoclonal bands, immunoglobulins, and viral antibodies in progressive myoclonus epilepsy

We studied CSF and serum samples from 16 patients with progressive myoclonus epilepsy (PME). These patients had juvenile-onset PME with evidence of autosomal recessive inheritance and no Lafora bodies. Twelve of the 16 patients with PME had immunologic abnormalities. Oligoclonal gamma bands were seen in six of the eight patients from whom sufficient CSF was available. The CSF albumin and serum/CSF albumin ratios were normal in all 16 patients, indicating the presence of intact blood-brain barriers. Six of the 16 patients showed increased CSF IgG levels and five had an increased CNS IgG synthesis. All patients had normal serum and CSF IgM and IgA levels. Three patients, all with bands, had reduced measles and/or vaccinia serum/CSF antibody ratios. The findings suggest altered immune response of the CNS of some patients with PME apparently caused by nonspecific immunostimulation.     

Circadian rhythms in serum and CSF cortisol of rhesus monkeys, and their modulation by timed injections ofl-5-hydroxytryptophan

Levels of in serum and cerebrospinal fluid have been studied in male and female rhesus monkeys. Untreated animals showed circadian rhythms of cortisol in both compartments, highest values occurring at 08.00 h and lowest at 20.00 h, but the decline following the morning peak was slower in cerebrospinal fluid (CSF) than in serum. Both levels and CSF/serum ratios (c. 0.017-0.027) were similar in males and females. The ratio between highest and lowest points on the circadian rhythm was greater for CSF (males: 2.50; females: 2.63) than for serum (1.69 and 1.78). There were significant correlations between CSF and serum levels in individual monkeys at each of the four time points studied. No circadian rhythm in CSF homovanillic acid (HVA) or 5-hydroxyindoleacetic acid (5-HIAA) was found, nor any correlation between these monoamine metabolites and cortisol levels. Injecting cortisol once daily in the evening (18.00h) resulted in greater proportional elevation in the CSF than in serum cortisol in samples taken two hours later, and the values in the two compartments were no longer correlated at this time. There was no effect on CSF 5-HIAA levels, Injecting L-5-hydroxytryptophan (L-5-HTP) (2.5 mg/kg) at four different time points produced abnormal daily patterns of cortisol secretion, the peak following the injection of L-5-HTP. The distortion of the normal circadian rhythm thus induced was greater in the CSF than in he serum, and CSF/serum ratios were increased one hour following L-5-HTP administration. The data suggested, but did not prove, that L-5-HTP injection may have produced the least Proportional elevation of cortisol at 08.00 h (at the time of normal daily maxima). 5-HIAA, but not HVA, was elevated one hour after L-5-HTP to 2-3 ties normal . A dose of 0.2 mg dexamethasone at 23.00 h suppressed cortisol levels in serum examined at 08.00 h the next day. This suppression was partially reversed by giving L-5-HTP one hour before taking the next morning's sample. Rhythmic and episodic changes in serum cortisol thus have a proportionally greater effect on the daily pattern of cortisol level in the CSF (and hence the cerebral compartment) than that in the vascular compartment, and thus the exposure of cortisol-sensitive tissues in the two compartments to cortisol may differ.     

The autosomal recessively inherited progressive myoclonus epilepsies and their genes

Autosomal recessively inherited progressive myoclonus epilepsies (PMEs) include Lafora disease, Unverricht-Lundborg disease, the neuronal ceroid lipofuscinoses, type I sialidosis (cherry-red spot myoclonus), action myoclonus–renal failure syndrome, and type III Gaucher disease. Almost all the autosomal recessively inherited PMEs are lysosomal diseases, with the exception of Lafora disease in which neither the accumulating material nor the gene products are in lysosomes. Progress in identifying the causative defects of PME is near-complete. Much work lies ahead to resolve the pathobiology and neurophysiology of this group of devastating disorders.     

Serotoninergic system in dementia of the Alzheimer type. Abnormal forms of 5-hydroxytryptophan and serotonin in cerebrospinal fluid

Serotonin (5-HT), its precursor 5-hydroxytryptophan (5-HTP), and its major metabolite 5-hydroxyindoleacetic acid (5-HIAA) were measured in the cerebrospinal fluid (CSF) of 14 patients with dementia of the Alzheimer type (DAT) and in nine controls by high-performance liquid chromatography with a novel multisensor coulometric detection system. Concentrations of both 5-HT and 5-HIAA detected by this system were lower than the concentrations obtained using conventional amperometric detection. This difference was caused by coelution of compounds that could be resolved from 5-HT and 5-HIAA by the multisensor coulometric system. One of the coelution compounds, observed in DAT but not in control CSF, behaved like a partially oxidized 5-HT. A compound behaving like partially oxidized 5-HTP was also observed in DAT CSF. Concentrations of 5-HTP, 5-HT, and 5-HIAA were lower in DAT CSF than in a corresponding fraction of control CSF. These results indicate involvement of the serotoninergic system in DAT and might lead to development of a diagnostic test for DAT.     

Serotonin and monoamine metabolites in cerebrospinal fluid in children: interrelationships and the influence of age, sex and precursor]

Cerebrospinal fluid and blood were taken from 15 non-neurologic children. Tryptophan(Trp), 5-HTP, 5-HT, 5-HIAA, HVA, MHPG in CSF, and 5-HT, free and total Trp(F-Trp and T-Trp) in serum were determined by HPLC method. Results showed that Trp, 5-HTP, 5-HT, 5-HIAA in CSF were positively correlated significantly. Good correlations were also found between F-Trp in serum and Trp in CSF (C-Trp), 5-HIAA and HVA, 5-HTP and MHPG. C-Trp, 5-HTP, 5-HT, 5-HIAA and HVA declined significantly with increasing age. MHPG was higher in male than in female children.     

Sex-linked differences in cortisol, ACTH and prolactin responses to 5-hydroxy-tryptophan in healthy controls and minor and major depressed patients

Some researchers have found that the administration of 5-hydroxytryptophan (5-HTP) results in increased cortisol secretion in major depressives but not in healthy controls. Other authors observed gender-related differences in cortisol responses to 5-HTP in major depressives. In order to investigate the pituitary/adrenal responsivity to 5-HTP, the authors measured cortisol, adrenocorticotropic hormone (ACTH) and prolactin (PRL) in 30 healthy controls and in 90 depressed patients; the hormone levels were determined in baseline conditions and 60, 90 and 120 min after 125 mg L-5-HTP (orally, non-enteric coated). We found that healthy men had significantly higher cortisol responses to L-5-HTP than healthy women. In the major depressives with melancholia and/or psychotic features these differences were reversed: women exhibited significantly higher cortisol and PRL responses than men. In the female group the most severely depressed patients had increased cortisol and PRL responses to L-5-HTP. The amplitudes of the cortisol, ACTH and PRL responses to L-5-HTP were significantly and positively correlated. It was concluded that the central serotonergic regulation of ACTH and PRL is significantly different between the sexes and between healthy controls, minor depressives and severely depressed patients.     

Measurement of 5-hydroxyindole compounds during L-5-HTP treatment in depressed patients.

L-5-hydroxytryptophan (L-5-HTP), an immediate serotonin precursor, was given to the hospitalized depressed patients in an open clinical trial of the Phase 2 study for antidepressive effects of the agent. A relatively small dose, 150mg orally for seven days, was employed, and seven of 14 patients responded to the treatment with mild or moderate emelioration of their depressive symptoms. Urinary excretion levels and plasma concentrations of three 5-hydroxyindole compounds, 5-HTP, 5-HT and 5-HIAA, were measured during the drug treatment. Approximately 70% of the orally administered dose of L-5-HTP was recovered from the urine of depressed patients. Major part of urinary indoleamine metabolites was free and conjugate 5-HIAA. Excretion levels of these compounds in urine were not consistenly altered in the depressed patients as compared to those in normal subjects. Clinical response to L-5-HTP treatment appeared to have some correlation with the biochemical measures in the depressed patients, that is, non-responders exhibited significantly lower excretion levels of 5-HT and 5-HIAA in urine, and lower plasma levels of 5-HT than responders. Administered L-5-HTP may not be fully utilized in the depressed patients who did not react to the agent.