Influence of ketogenic diet on the clinical effects and electroencephalogram features in 31 children with pharmacoresistant epileptic encephalopathy / 中华儿科杂志

<p><b>OBJECTIVE</b>To investigate the effect of ketogenic diet (KD) on the clinical and electroencephalogram features in children with pharmacoresistant epileptic encephalopathy.</p><p><b>METHOD</b>Thirty-one children (19 boys, 12 girls) aged 7 months to 7 years (mean 2 years 5 month) with epilepsy refractory to conventional antiepileptic drugs (AEDs) were included in this study. In addition to their original AED treatment, the children were assigned to different ketogenic diets based on their age. The prospective electro-clinical assessment was performed prior to the KD and then one week, one month and again 3 months after the initiation of therapy, respectively.</p><p><b>RESULT</b>The reduction of seizure frequency in 52%, 68% and 71% of all patients exceeded 50% one week, one month and three months after KD treatment respectively. KD is particularly effective in myoclonic astatic epilepsy (MAE; Doose Syndrome) and West syndrome with 100% and 81.25% of the patients having a greater than 50% seizure reduction, respectively. After 3 months of KD treatment, more than 2/3 patients experienced a reduction in interictal epileptiform discharges (IEDs) and improvement in EEG background.</p><p><b>CONCLUSION</b>The clinical and electroencephalographic improvement confirms that KD is beneficial in children with refractory epilepsy.</p>

Cyclooxygenase-2 inhibitor inhibits hippocampal synaptic reorganization in pilocarpine-induced status epilepticus rats / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

<p><b>OBJECTIVE</b>To examine modulations caused by cyclooxygenase-2 (COX-2) inhibitors on altered microenvironments and overbalanced neurotransmitters in pilocarpine-induced epileptic status rats and to investigate possible mechanisms.</p><p><b>METHODS</b>Celecoxib (a COX-2 inhibitor) was administered 45 min prior to pilocarpine administration. The effects of COX-2 inhibitors on mIPSCs (miniature GABAergic inhibitory postsynaptic currents) of CA3 pyramidal cells in the hippocampus were recorded. Expressions of COX-2, c-Fos, newly generated neurons, and activated microgliosis were analyzed by immunohistochemistry, and expressions of alpha-subunit of gamma-amino butyric acid (GABA(A)) receptors and mitogen-activated protein kinase/extracellular signal-regulated protein kinase (MAPK/ERK) activity were detected by Western blotting.</p><p><b>RESULTS</b>Pretreatment with celecoxib showed protection against pilocarpine-induced seizures. Celecoxib prevented microglia activation in the hilus and inhibited the abnormal neurogenesis and astrogliosis in the hippocampus by inhibiting MAPK/ERK activity and c-Fos transcription. Celecoxib also up-regulated the expression of GABA(A) receptors. NS-398 (N-2-cyclohexyloxy-4-nitrophenyl-methanesulfonamide), another COX-2 inhibitor, enhanced the frequency and decay time of mIPSCs.</p><p><b>CONCLUSION</b>The COX-2 inhibitor celecoxib decreased neuronal excitability and prevented epileptogenesis in pilocarpine-induced status epilepticus rats. Celecoxib regulates synaptic reorganization by inhibiting astrogliosis and ectopic neurogenesis by attenuating MAPK/ERK signal activity, mediated by a GABAergic mechanism.</p>

Morphological and behavioral consequences of recurrent seizures in neonatal rats are associated with glucocorticoid levels / 神经科学通报·英文版

<p><b>OBJECTIVE</b>It is well documented that epilepsy can increase neurogenesis in certain brain regions and cause behavioral alternations in patients and different epileptic animal models. A series of experimental studies have demonstrated that neurogenesis is regulated by various factors including glucocorticoid (CORT), which can reduce neurogenesis. Most of studies in animal have been focused on adulthood stage, while the effect of recurrent seizures to immature brain in neonatal period has not been well established. This study was designed to investigate how the recurrent seizures occurred in the neonatal period affected the immature brain and how CORT regulated neurogenesis in immature animals.</p><p><b>METHODS</b>Neonatal rats were subjected to 3 pilocarpine-induced seizures from postnatal day 1 to day 7. Then neurogenesis at different postnatal ages (i.e. P8, P12, P22, P50) was observed. Behavioral performance was tested when the rats were mature (P40), and plasma CORT levels following recurrent seizures were simultaneously monitored.</p><p><b>RESULTS</b>Rats with neonatal seizures had a significant reduction in the number of Bromodeoxyuridine (BrdU) labeled cells in the dentate gyrus compared with the control groups when the animals were euthanized on P8 or P12 (P<0.05); whereas there was no difference between the two groups on P22. Until P50, rats with neonatal seizures had increased number of BrdU-labeled cells compared with the control group (P<0.05). In Morris water maze task, pilocarpine-treated rats were significantly slower than the control rats at the first and second day, and there were no differences at other days. In probe trial, there was no significant difference in time spent in the goal quadrant between the two groups. Endocrine studies showed a correlation between the number of BrdU positive cells and the CORT level. Sustained increase in circulating CORT levels was observed following neonatal seizures on P8 and P12.</p><p><b>CONCLUSION</b>Neonatal recurrent seizures can biphasely modulate neurogenesis over different time windows with a down-regulation at early time and up-regulation afterwards, cause persistent deficits in cognitive functions of adults, and increase the circulating CORT levels. CORT levels are related with the morphological and behavioral consequences of recurrent seizures.</p>

Neurogenesis of dentate granule cells following kainic acid induced seizures in immature rats / 中华儿科杂志

<p><b>OBJECTIVE</b>Data accumulated over the past years have led to widespread recognition that neurogenesis, the emergence of new neurons, persists in the hippocampal dentate gyrus of the adult mammalian brain, and can be increased by seizures in multiple models. Also, aberrant reorganization of dentate granule cell axons, the mossy fiber sprouting, occurs in human temporal lobe epilepsy and rodent epilepsy models. However a number of studies suggest that the immature brain is less vulnerable to the morphologic alteration of hippocampus after seizures. The goal of this study was to determine whether the seizures can induce dentate granule cell neurogenesis and mossy fiber sprouting in the immature rat.</p><p><b>METHODS</b>Seizures was elicited by unilateral microinfusion of kainic acid (KA, 1 micro g) into the amygdula at postnatal day 15 (P15). Rat pups were given bromodeoxyuridine (BrdU) intraperitoneally on day 5 after KA administration and killed 7 d or 21 d later. The brains were processed for BrdU mitotic labeling combined with double-label immunohistochemistry using neuron-specific, early differentiation marker TuJ1 (betaIII tubulin) or granule-specific marker CaBP (calcium-binding protein calbindin D28k) as well as glia-specific marker GFAP (glial fibrillary acidic protein). Mossy fiber sprouting in intermolecular layer and CA3 subfield was assessed in Timm-stained sections both 1 month and 3 months after KA administration by using a rating scale and density measurement.</p><p><b>RESULTS</b>The dentate BrdU-immunoreactive cells of the KA-treated rats increased significantly compared with those of control rats on day 7 and 21 after BrdU administration (7 d: 244 +/- 15 vs. 190 +/- 10; 21 d: 218 +/- 19 vs. 133 +/- 12, P < 0.05). Approximately 80.2% and 78.7% of BrdU-labeled cells coexpressed TuJ1 in KA-treated rats and control rats on day 7 after BrdU respectively (P > 0.05). On 21 d after BrdU, 60.2% and 58.2% of dentate BrdU-labeled cells coexpressed GaBP in KA-treated rats and control rats respectively (P > 0.05). GFAP colocalized with 3%-5% dentate BrdU-labeled cells in the rats of both groups on day 7 and 21 after BrdU. It was also demonstrated that status epilepticus at P15 did not result in any detectable mossy fiber sprouting within the hippocampus both 1 month and 3 months after KA administration.</p><p><b>CONCLUSIONS</b>KA induced seizures can increase granule cell neurogenesis in the immature rat. Most of newly appeared cells migrate from subgranular proliferation zone (SGZ) into granule cell layer, the hilus as well as the molecular layer, and there they can differentiate into granule neurons. These observations also indicate that there is an early developmental resistance to seizure-induced mossy fiber sprouting in the immature brain.</p>

Malnutrition increases hippocampal neurogenesis in the immature rat after status epilepticus / 中华儿科杂志

<p><b>OBJECTIVE</b>Neurogenesis in the dentate gyrus of hippocampus persists in brain of the immature and adult mammalian including human and it can be regulated by physiological and pathological events including nutritional status and seizures. The present study was designed to investigate the potential effects of malnutrition followed by status epileptics on hippocampal neurogenesis in the immature rat.</p><p><b>METHODS</b>Rat pups were divided into 4 groups: malnourished (M), nourished (N), malnourished plus seizures (MS) and nourished plus seizures (NS). The rat pups of group M and group MS were maintained on a starvation regimen from postnatal day 2 (P2) to P18. The status epilepticus of the rat pups in group MS and group NS was elicited by unilateral microinfusion of kainic acid (KA) into the amygdula at P15. Rat pups of the 4 groups were given bromodeoxyuridine (BrdU) intraperitoneally twice daily for 2 days beginning at P17. At P19, the rat pups were killed and the brains were processed for BrdU mitotic labeling combined with double-label immunohistochemistry using early neuron- or glia-specific markers TuJ1 (beta III tubulin) or GFAP (glial fibrillary acidic protein).</p><p><b>RESULTS</b>There were no significant differences in the latent time of seizure between group M and group N [(12.4 +/- 2.6) min vs. (12.1 +/- 2.9) min, P < 0.05]. Histological assessment did not reveal any evidence of hippocampal cell loss after status epilepticus in either group. BrdU-labeled cells were significantly higher in the rats of group MS (374 +/- 18) than group M (303 +/- 20), group NS (312 +/- 24) than group N (269 +/- 18), respectively (P < 0.01). There was also significant difference between group M and group N, group MS and group NS, respectively (P < 0.01). No significant difference was seen between the rats of group NS and group M (P > 0.05). Approximately 60% of BrdU-labeled cells coexpressed TuJ1, and 5% approximately 10% of those co-expressed GFAP.</p><p><b>CONCLUSION</b>Early malnutrition do not alter KA seizure susceptibility and the behavioral manifestations of seizures at P15. Although malnutrition and status epilepticus can increase the proliferation of newly developed cells in the immature rat respectively, malnutrition followed by status epilepticus further increases this proliferation. Furthermore, most of newly developed cells differentiate into early neurons.</p>