Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0036572 (seizures)
 80,221 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Melatonin, which is used to treat sleep disorders, has anticonvulsant properties. The authors measured salivary melatonin and cortisol, at baseline and following seizures, in patients with intractable temporal lobe epilepsy and controls. Melatonin was reduced in patients with epilepsy at baseline compared with controls, and increased threefold following seizures. Cortisol also increased following seizures. Patients with intractable epilepsy have low baseline melatonin levels that increase dramatically following seizures.
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PMID:Patients with intractable epilepsy have low melatonin, which increases following seizures. 1111 38

The objective of this study was to assess melatonin production in patients with acute intermittent porphyria (AIP), with and without known epileptic seizures, as a guide to whether melatonin may have anti-convulsive or pro-convulsive effects in AIP. Melatonin concentration in urine, sampled over eight hours on two consecutive nights, was analysed in eight AIP patients with epileptic seizures and in 14 AIP relatives without epilepsy. The AIP patients with epileptic seizures had a significantly lower urinary excretion of melatonin, compared with their AIP relatives without epilepsy, which may indicate that melatonin has a protective effect on seizures.
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PMID:Melatonin and epileptic seizures in patients with acute intermittent porphyria. 1117 50

The neuronal isoform of nitric oxide synthase (nNOS), a NADPH-dependent diaphorase, is considered to play a role in motoneuron death induced by sciatic nerve transection in neonatal rats. Neuronal loss in these circumstances has been correlated with nitric oxide (NO) production and NADPH-diaphorase positivity in motoneurons after axotomy. In the present study we looked for a possible protective effect of melatonin, an antioxidant agent and inhibitor of nNOS, on spinal motoneurons after axonal injury. Neonatal Wistar rats (P2) were submitted to sciatic nerve transection and allowed to survive to P7. Melatonin at doses of 1, 5, 10, 50 and 100 mg/kg was given subcutaneously before and at intervals after the surgery. Controls operated in the same way received dilution vehicle or no treatment. The animals were killed by perfusion of fixative and the spinal cord was examined in serial paraffin sections. The motoneurons of the sciatic pool were counted in the axotomized and contralateral sides. Immunohistochemistry for nNOS and glial fibrillary acidic protein was used to evaluate nNOS expression in the axotomized cells and the astrocytic response. We found that melatonin at doses of 1-50 mg/kg decreased neuronal death. Astrocytic hypertrophy in melatonin treated animals was less intense. There were no differences in nNOS expression between treated and control rats, and surviving motoneurons of the sciatic pool did not express the enzyme, suggesting that nNOS may not be involved in neuronal death or survival in these experimental conditions. Possible mechanisms of melatonin neuroprotection, which was equally effective at doses of 1-50 mg/kg, are discussed. Doses of 50 and 100 mg/kg caused failure to thrive, seizures or death. The fact that neuroprotective doses were far smaller than toxic ones should encourage testing of melatonin in neurologic diseases.
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PMID:Neuroprotective action of melatonin on neonatal rat motoneurons after sciatic nerve transection. 1181 4

The pineal hormone melatonin is the mediator of external light to physiologic adaptation to day and night rhythms, it regulates reproduction in animals but attempts to utilize melatonin in women for contraception have failed. Melatonin seems to be the natural hormone to facilitate sleep in insomniac patients and causes no hang over. When applied together with benzodiazepine it allows reduction of benzodiazepine without withdrawal effects. It should be applied 2 h before sleeping time in doses between 3 and 5 mg. Melatonin acts via the gamma-aminobutyric acid- and benzodiazepine receptor explaining its success in treatment of seizures in children and in adults. Constant application of benzodiazepine reduced the production of natural melatonin in rats, supporting the evidence that long-term application of benzodiazepine in humans does not restore sleeping habits but reduces natural sleeping habits even more. Low melatonin levels were seen in bulimia or neuralgia and in women with fibromyalgia; replacement reduced pain, sleeping disorders, and depression in fibromyalgia and bulimia. Melatonin profiles are a diagnostic tool to distinguish between several forms of depression, like major depression, winter depression (SAD), unipolar depression, delayed sleep phase syndrome (DSPS). In patients with a major depression success with antidepressants correlated with an increase in their melatonin profiles but only patients suffering from DSPS can be successfully treated with melatonin. In perimenopausal women melatonin administration did produce a change in LH, FSH and thyroid hormones. Some oncostatic properties are supported by cell culture work and studies in animals. In Nordic countries indigenous people suffer less from breast and prostate cancer, winter darkness seems to protect. The supposedly increased melatonin levels created the 'melatonin hypothesis'. Epidemiological studies did show that blind people indeed have half the rate of breast cancers, supporting the hypothesis. Controversial results concerning melatonin and insulin resistance and glucose tolerance have been published. In postmenopausal women application of melatonin reduced glucose tolerance and insulin sensitivity. Pregnant women should avoid melatonin, since its teratogenic effect is not known. Patients suffering from non-hormone dependent tumors, like leukemia, should avoid melanin, since tumor growth was promoted in animal experiments. It can be expected that melatonin will receive wide consideration for treatment of sleeping disturbances, jet lag, and fibromyalgia once an oral formulation becomes available in Europe.
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PMID:Melatonin deficiencies in women. 1195 97

Daily melatonin (10-50 mg/kg, i.p.) treatment at 08.30 h or 17.00 h for 1 week of female rats (2-months-old) increased the latency to the appearance of the first convulsion in the pilocarpine-induced seizure model. Other behavior parameters remained unaltered. The anticonvulsant effect of melatonin seemed to be more intense at the light-dark transition. Moreover, the effect of repeated melatonin treatment was also age-related, since it showed a lower threshold in 2-month-old than in 21-day-old rats, and the acute treatment was not efficient. [3H]N-methylscopolamine binding was unaltered in the hippocampus and striatum of adult rats after the association of melatonin and pilocarpine. While muscarinic binding was unaltered in adult rats, it increased in the hippocampus of young rats in the presence of melatonin (50 mg/kg) and pilocarpine, and did not change in the striatum. Melatonin partially recovered [3H]GABA binding in the hippocampus in the presence of pilocarpine-induced seizures, and intensified pilocarpine effects in the striatum of adult rats.
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PMID:Attenuating effects of melatonin on pilocarpine-induced seizures in rats. 1197 67

The present study was carried out to investigate the effect of melatonin, a potent antioxidant, and phenytoin, a conventional antiepileptic, against FeCl3-induced posttraumatic seizures. Male Wistar rats weighing 200-250 g were implanted with epidural electrodes and allowed to recover. After the recording of baseline EEG, FeCl3 (5 ul, 100 mM) was administered intracortically over a period of 5 min and EEG was monitored for 2 h. Subsequently, rats were sacrificed to estimate oxidative stress, i.e., the amount of malondialdehyde (MDA) in whole brain tissue. A sham group was run parallel with saline (pH adjusted), and a similar protocol for EEG recording and estimation of oxidative stress was followed. FeCl3-treated animals exhibited epileptiform EEG changes (high amplitude sharp waves of increased frequency and polyspikes) within 15 min, which continued throughout the period of observation. MDA levels were found to be significantly elevated as compared to the sham group. Melatonin (50 mg/kg i.p.) administered 30 min before FeCl3 injection delayed the onset of appearance of epileptiform EEG changes, while at a 100 mg/kg dose of there was complete protection, as none of the animal exhibited epileptiform EEG discharge. Brain MDA levels were also significantly reduced in melatonin (50 and 100 mg/kg dose)-treated animals as compared to the vehicle-treated FeCl3-injected rats. In the phenytoin group, all animals showed epileptiform EEG discharge. However, phenytoin at both 50 and 100 mg/kg dose delayed the onset of epileptiform EEG discharge. There were no significant changes in brain MDA levels in the phenytoin-treated group as compared to controls. Melatonin and phenytoin at doses of 100 mg/kg did not show any sign of motor impairment as observed during the rota-rod test. These findings showed a superior protective effect of melatonin over phenytoin in an intracortical FeCl3 model of posttraumatic epilepsy.
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PMID:Effect of melatonin and phenytoin on an intracortical ferric chloride model of posttraumatic seizures in rats. 1208 76

Melatonin is known to have a neuroprotective effect by preventing epileptic seizures, which are normally induced by cyanide. To demonstrate the neuroprotective function of melatonin, we examined cell death and changes in plasma melatonin level in KCN-treated mice. Neuronal cell death is shown in substantial nigra of KCN-treated groups. In melatonin-treated groups, this cell death decreased in substantia nigra. Plasma melatonin level at 12:00 was significantly decreased to 52.6% after KCN injection as compared to the normal group. In contrast, melatonin level was significantly decreased (74.5%) in KCN + melatonin group. Melatonin level at 24:00 was significantly decreased to 57.0% after KCN injection and also significantly decreased to 81.0% in KCN-melatonin group as compared to the normal group. Results from the present study suggest that melatonin prevents neuronal cell death in KCN-induced brain.
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PMID:Effects of melatonin on KCN-induced neurodegeneration in mice. 1232 6

Oxidative Stress is implicated as one of the primary factors that contribute to the development of neurodegenerative diseases like Alzheimer's Disease, Parkinsonism and neurological conditions like epileptic seizures, stroke, brain damage, neurotrauma etc. The increased formation and release of oxygen free radicals coupled with the rather low antioxidative potential of the central nervous system are the major reasons that account for the enhanced oxidative stress seen in neuronal cells. In addition to this, brain is also enriched with polyunsaturated fatty acids that render neuronal cells easily vulnerable to oxidative attack. The fact that there is increased incidence of neurodegenerative disorders in aged individuals, has prompted many investigators to search for a common factor whose progressive decline with increase in age could account for increased oxidative stress resulting in senescence and age associated degenerative diseases. Since melatonin, the hormone secreted from the pineal gland has a remarkable anti-oxidant property and whose rate of production declines with increase in age, has prompted many to suggest that this hormone plays a crucial role in the genesis of neurodegenerative diseases. Melatonin cannot only scavenges oxygen free radicals like super oxide radical (O2-), hydroxyl radical (*OH), peroxyl radical (LOO*) and peroxynitrite anion (ONOO-), but can also enhance the antioxidative potential of the cell by stimulating the synthesis of antioxidative enzymes like super oxide dismutase (SOD), glutathione peroxidase (GPX), and also the enzymes that are involved in the synthesis of glutathione. In many instances, melatonin increases the expression of m RNA's of the antioxidative enzymes. Melatonin administration has been shown to be effective in counteracting the neurodegenerative conditions both in experimental models of neurodegenerative diseases and in patients suffering from such diseases. A disturbance of melatonin rhythm and secretion also has been noted in patients suffering from certain neurodegenerative diseases. From all these, it is evident that melatonin has a neuroprotective role.
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PMID:Melatonin oxidative stress and neurodegenerative diseases. 1258 15

We examined the effect of melatonin on brain levels of amino acids and nitric oxide (NO) after pentylenetetrazole (PTZ)-induced seizures in rats. Animals were treated with melatonin (10-160 mg/kg, i.p.) 30 min before PTZ administration (100 mg/kg, s.c.), and were killed 3 hr later. At the dose of 80 mg/kg, melatonin significantly increased the latency (5.7-12.7 min) and decreased the duration (31.2-18.4 s) of the first seizure, reducing PTZ induced mortality from 87.5 to 25%. After kill, brains were removed and neurotransmitters and nitrite levels measured in prefrontal cortex (PF), parieto-temporal cortex (PF), striatum (ST), hippocampus (HP) and brain stem (BS) by high performance liquid chromatography. PTZ treatment increased glutamine levels in all brain areas studied, without changes in glutamate, gamma-amino butyric acid (GABA) and glycine. Aspartate and taurine increased in PF and PT and in HS and PT, respectively. Melatonin administration displayed a dose-dependent effect. At doses of 10-40 mg/kg, melatonin counteracted the PTZ-induced glutamine increase and reduced both glutamate and aspartate levels in the studied areas, with minor changes in GABA and glycine content. At doses of 80 and 160 mg/kg, the levels of glutamine, and glutamate, and to a lesser extent aspartate increased, whereas serine levels did not change. These two doses of melatonin also increased taurine, GABA and glycine in most brain areas studied. Treatment with melatonin (40-160 mg/kg) significantly decreased nitrite content in PT cortex, ST and BS areas of epileptic rats, without changes in the other brain regions. The results suggest that the anticonvulsant property of melatonin involves a modulation of both brain amino acids and NO production.
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PMID:Changes in brain amino acids and nitric oxide after melatonin administration in rats with pentylenetetrazole-induced seizures. 1282 14

The pharmacokinetic and pharmacodynamic interaction of phenytoin and carbamazepine with melatonin was studied in a maximal electroshock seizure (MES) model in mice. The anticonvulsant ED(20), ED(33), ED(50) and ED(100) of phenytoin and carbamazepine, and ED(50) of melatonin were determined. Thereafter, the subanticonvulsant doses of phenytoin and carbamazepine were combined with ED(50) dose of melatonin. In combination with melatonin, 100% protection against seizures was achieved with phenytoin and carbamazepine in doses as low as ED(50) and ED(33), respectively. Serum levels of phenytoin and carbamazepine in animals that received ED(50) dose of phenytoin and carbamazepine per se, were not significantly different to those of the groups that received melatonin also. The study suggests that the synergistic antiepileptic effect is most likely a pharmacodynamic interaction, and not due to pharmacokinetic changes. Melatonin, thus, can be a potential adjunct to antiepileptic drugs, achieving a therapeutic effect at lower concentrations, hence limiting their dose-related toxicities.
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PMID:Modulation of antiepileptic effect of phenytoin and carbamazepine by melatonin in mice. 1507 7


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