ObjectiveTo explore the dynamic expression changes of neuronal growth and differentiation-associated miR-124a and miR-9 in the process of epileptogenesis. MethodsEstablish the lithium-pilocarpine induced status epilepticus (SE) rat model. Animal behavior change induced by SE as well as in the period of chronic epilepsy was observed by naked-eye or video-recording. Major time points for the study were chosen at 1d, 7d, 14d and 28d post-SE, on which the post-SE rats were decapitated and their hippocampal specimens were obtained. Total RNA from each specimen was extracted and qPCR was exploited to detect miR-124a and miR-9 expression in the specimens. Statistical analysis was used to show the dynamic expressional changes of miR-124a and miR-9 in rat hippocampus at 1d, 7d, 14d and 28d post-SE during the process of epileptogenesis. ResultsCompared with normal rats, the expression level of miR-124a in rat hippocampus did not show a significant difference at 1d post-SE, but it had shown markedly differences at 7d, 14d and 28d post-SE(P < 0.05), with a declining trend. Compared with normal rats, the expression level of miR-9 had demonstrated significant differences at 1d, 7d, 14d and 28d post-SE(P < 0.05)with a generally increasing trend, although there was slight fluctuation of expressional up-regulation at 7d post-SE. ConclusionNeuronal growth and differentiation-associated miR-124a and miR-9 had shown dynamic changes of down-regulation or up-regulation in the process of epileptogenesis. It can be suspected that miR-124a and miR-9 take part in hippocampal neurogenesis post-SE and be involved in epileptogenesis process.
ObjectiveImpaired breathing during and following seizures is an important cause of sudden unexpected death in epilepsy (SUDEP), but the network mechanisms by which seizures impair breathing have not been thoroughly investigated. Progress would be greatly facilitated by a model in which breathing could be investigated during seizures in a controlled setting. MethodRecent work with an acute Long-Evans rat model of limbic seizures has demonstrated that depression of brainstem arousal systems may be critical for impaired consciousness during and after seizures. We now utilize the same rat model to investigate breathing during partial seizures with secondary generalization. ResultBreathing is markedly impaired during seizures(P < 0.05;n=21), and that the severity of breathing impairment is strongly correlated with the extent of seizure propagation (Pearson R=-0.73;P < 0.001;n=30). ConclusionSeizure propagation could increase the severity of breathing impairment caused by seizures. Based on these results, we suggest that this animal model would help us to improve understanding of pathways involved in impairment of breathing caused by seizures and this is an important initial step in addressing this significant cause of SUDEP in people living with epilepsy.
Objective To summarize and analyze the clinical and video-EEG (VEEG) characteristics of adult sleep-related epilepsy, so as to provide evidence for clinical diagnosis, differential diagnosis and treatment. Methods The clinical data, routine EEG and long-term VEEG of 187 adult patients with sleep-related epilepsy treated in Department of Neurology, Xiangya Hospital, Central South University from January 2017 to December 2017 were retrospectively analyzed by χ2 test. Results Clinical manifestations: The duration of sleep-related epilepsy in 187 adults was concentrated in 1～10 years (101 cases, 54.01%); the frequency of seizures was mainly from several to dozens of times a year (99 cases, 52.94%); 119 cases (63.64%) had two or more types of seizures. Among the patients, 121 cases (39.29%) had focal origin, 152 cases (49.35%) had bilateral tonic clonus and 110 cases (58.82%) were treated with two or more drugs. EEG results: ① The detection rate of epileptiform discharges in routine EEG was 22.78%, and that in long-term video EEG was 80.43%. There was significant difference between the two methods (P< 0.01); ② Eighteen epileptiform discharges were monitored by routine EEG during interparoxysmal period and 111 epileptiform discharges were monitored by video EEG; and ③ Fifty-six epileptic events were monitored and all occurred in the process of long-term VEEG monitoring, 50 of them occurred in sleep (89.29%) and 6 in awake (10.71%); 45 cases (80.36%) were diagnosed as epileptic seizures, 9 cases (16.07%) were diagnosed as non-epileptic seizures, and 2 cases (3.57%) could not be determined. ④ The detection rate of epileptic discharges during sleep was higher than that during awake period in long-term VEEG monitoring (P< 0.01). The detection rate of epileptiform discharges in NREM stage I–II was the highest in sleep stage. Conclusion Sleep-related epilepsy in adults has certain clinical features and EEG manifestations. Compared with conventional EEG, long-term video-EEG can improve the detection rate of epileptiform discharges, provide diagnostic basis for the qualitative analysis of sleep-related seizures, and reflect the relationship between epileptiform discharges and sleep, and provide basis for the clinical diagnosis and treatment of sleep-related epilepsy in adults.