Abstracts

Rationale:      Melatonin (N-acetyl-5-methoxytryptamine) is a multifunctional hormone that is a neuroprotective agent and an antioxidant, plays a key role in the coordination and synchronization of the nervous system. It has a high permeability through the blood-brain barrier, therefore fluctuations in its concentration in the peripheral blood have a significant effect on the functional state of the brain neurons. Melatonin has a subtle specific inhibitory effect, speeds up the falling asleep process.     The purpose of this research is to study the level of melatonin in patients with epilepsy, depending on the severity of the disease, the type and frequency of seizures.  Methods: The studies were carried out on the basis of clinical symptoms and instrumental data analysis. The detection of melatonin in the blood serum was carried out by applying a modified Cole and Crank fluorometric method with orthophthalic aldehyde. Taken into account the circadian rhythms of melatonin production, the studies were conducted from 7:00 to 8:00 am, during the period of maximum secretion.The EEG (electroencephalography) and EEG-video monitoring were used as screening techniques. Results:      The clinical material was analyzed on the basis of the survey of 256 patients with epilepsy, whose average age was 32-37 years. On the basis of the multifactorial analysis of the clinical data, three groups of patients were singled out: the 1st group –  patients with an unfavorable, progressive disease course; the 2nd group – patients with a favorable course of the disease; the 3rd group – patients with the onset of epilepsy. The severe adverse course of the disease was confirmed by the presence of pronounced EEG changes. The control group is 52 practically healthy people.      In all patients, a significant decrease in morning melatonin secretion was found on average by 25.6% in comparison with the control group indicators (Table 1).      A low level of melatonin was characteristic of patients with primary and secondary generalized convulsive attacks, as well as with prolonged complex partial attacks: an average of 0.478±0.017 μM/L in the 1-st group and 0.566±0.012 μM/L in the 2-nd one. In the third group, in the presence of generalized tonic-clonic seizures, a sufficiently low content of this hormone was also detected, on average 0.702±0.014 μM/L.      In patients with epileptic seizures associated with the sleep cycle, the melatonin level was significantly lower than on a par in the groups (Table 2).      In 28 patients with generalized convulsive epileptic seizures associated with sleep, an EEG with sleep deprivation was made. The deterioration of the EEG pattern in 89.3% of cases was accompanied by the appearance of new epileptiform phenomena: spikes, "spike-slow wave" complexes, high-amplitude sharp waves. In 57.1% of patients, a significant focal "slowing down" of the EEG was registered. Conclusions: Thus, melatonin deficiency can be one of the reasons for increasing the activity of excitatory systems. The correlation between epileptiform changes in the EEG and certain decrease in melatonin level has also been detected. The higher the melatonin level in patients, the lower is the convulsive readiness of the organism and the more favorable course of epilepsy. Funding: Personal funds