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Xiaoyun Liu,1,* Liling Yang,1,* Yuxiang Han,1 Jingjing Xu,2 Zaiying Pang,1 Yifeng Du,1 Yabo Feng,1,* Youting Lin1,* 1Department of Neurology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan City, Shandong Province, 250021, People’s Republic of China; 2Department of Geriatrics, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan City, Shandong Province, 250021, People’s Republic of China*These authors contributed equally to this workCorrespondence: Yabo Feng; Youting LinDepartment of Neurology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, No. 324, Jingwu Road, Huaiyin Zone, Jinan City, Shandong Province, 250021, People’s Republic of ChinaTel/Fax +86-531‐68776354Email fyb-sd@hotmail.com; youtinglin2019@126.comObjective: The purpose of this study was to illustrate the electrophysiological features of sleep disturbances in patients with anti-leucine-rich glioma-inactivated protein 1 (anti-LGI1) encephalitis in both active and recovery stages.Methods: Retrospectively filed video electroencephalogram (VEEG) and polysomnography (PSG) data in 24 patients with anti-LGI1 encephalitis were analyzed in comparison with that in 20 individuals without sleep disorders as control group.Results: Sleep efficiency (SE) and total sleep time involving REM and NREM sleep were significantly decreased in patients with anti-LGI1 encephalitis during the active stage compared to that during the recovery stage and in the control group. Imbalanced sleep structure was found, demonstrated by elevated N1, decreased N3 and REM components, as well as abnormal N2 structure characterized with significantly lower spindle duration and density during the active stage. These findings were independent of the presence of nocturnal episodic events or sleep hyperkinetic movements (HMs). HMs were present in 11/23 patients throughout NREM and REM sleep (nonspecific in sleep stages) during the active stage. During the recovery stage, SE and sleep structures were dramatically improved, including the percentage of N3 and REM sleep, spindle duration and density. Ten of 11 patients with HMs were followed up. HMs were totally remitted in 3 patients and still persistent in 1, while evolved into REM sleep behavior disorder (RBD) in 4 with comorbid periodic limb movement syndrome (PLMS) in 3/4, and only PLMS in 2.Conclusion: Sleep disturbances were remarkable and intrinsic features in active anti-LGI1 encephalitis, marked by overall disruptions of both NREM and REM sleep, as well as the presence of HMs, which tend to evolve into RBD or PLMS during the recovery stage. Long-term follow-up with PSG is needed, especially for those patients with severe sleep disturbances during the active phase.Keywords: anti-leucine-rich glioma-inactivated protein 1 encephalitis, video electroencephalogram, polysomnography, sleep disturbances, REM sleep behavior disorder, periodic limb movement in sleep

Knee instability as a symptom of ligament injury usually only receives attention when it causes pain or impacts patients’ mobility in China. In this study both the physical and psychosocial impact of an innovative approach to treatment, Half-cut Wood Training, was examined. Twenty individuals with knee instability who received Halfcut Wood Training (Intervention group) and twenty two individuals with knee instability who did not receive Half-cut Wood Training (as Control group) participated in the study. The electric WIFI based HBF-306 was used to collect the anthropometry and biomedical data. Symptom severity was assessed by a doctor and through response to a specific question. Half-cut Wood Training was used as the intervention for the knee instability patients, and the effects among pre-intervention, post-intervention and control group on self-esteem, self-efficacy, quality of life and reductions in knee instability were assessed and compared to patients in the control group. The Half-cut Wood Training has significantly improved the physical health, self-esteem, self-efficacy, legs and feet functioning of patients in the intervention group compared with control group. Moreover, the Symptom were decreased (F = 15.47, P < 0.001), and the doctor reported knee function was improved (F = 36.20, P < 0.001). The subgroups including number of sessions of attending the Half-cut Wood Training had effects on the reduction of symptoms and duration of training time more than one month has effect on the improvement of physical health. Half-cut Wood Training provides beneficial means of improving knee function, self-esteem, self-efficacy, and physical health of the quality of life of patients with the knee instability.

Purpose Late-onset epilepsy due to autoimmune dysfunction has been reported. However, definitive diagnosis requires positive antibody results. As a result, patients with negative antibody results, but presenting with classical manifestation of autoimmune epilepsy, may be managed as suspected cases. In this study, we aim to isolate and profile the concentration of cytokines/chemokines in the cerebrospinal fluid (CSF) and the serum to ascertain if they could act as alternative diagnostic biomarkers. Patients and methods Twenty patients aged ≥50 years were considered in this study. Ten patients were diagnosed with suspected autoimmune epilepsy (sAE) based on clinic manifestation, electroencephalogram, magnetic resonance imaging, and with negative antibody results of the serum and the CSF. The equivalent control group exhibited neurological disorders due to non-inflammatory pathologies. Serum and CSF were analyzed for cytokines/chemokines concentration, including interleukin (IL)-6, IL-10, IL-17, chemokine (C-X-C motif) ligand (CXCL)12 and CXCL13, as well as high-mobility group box protein 1 (HMGB1) and B cell activation factor (BAFF)). Results The CSF levels of IL-6, IL-17, HMGB1, and CXCL12 were significantly higher in the sAE group than in the control group. There was no difference in the CSF levels of IL-10, CXCL13 and BAFF. The serum levels of HMGB1 and CXCL12 were elevated in the sAE group compared with the control group, and there was no statistical difference in the serum levels of IL-6, IL-10, IL-17, CXCL13, and BAFF between the two groups. Conclusion Our study shows that cytokines/chemokines may act as alternative biomarkers for diagnosis of sAE. The activation of both HMGB1/CXCL12-mediated immunity and T helper cells 17 (Th17) cells may be playing a central role in the pathogenesis of sAE. We suggest that cytokines/chemokines be treated as adjuvant biomarkers, instead of solely relying on antibody screening test. However, a larger cohort in a prospective approach is required to validate our findings.

Purpose The purpose of this study was to characterize the spectrum of motor events in patients with acute anti-leucine-rich glioma-inactivated protein 1 (anti-LGI1) encephalitis through video-electroencephalogram (VEEG) recordings. Method We collected data retrospectively from 16 patients diagnosed with anti-LGI1 encephalitis who had completed VEEG recording during hospitalization. Results VEEG monitoring lasted a median of 11.0 h (range 4.5∼20). Fourteen types of seizures were recorded in 9 patients (56.3 %). Eight of the 14 types of seizures demonstrated typical ictal EEG evolution (including 2 subclinical seizures), 3/14 demonstrated EEG electrodecremental events (EDE) at onset but without further evolution, and 3/14 could be only judged by analyzing semiology. FBDS was recorded in 6 patients (37.5 %), and all these attacks were followed by epileptic seizures. Simple hyperkinetic movements (HMs), such as jerk-like or twisting movements, were found in 8 (50 %) patients, and 6 of them had complex HMs, such as manipulating movements or mimics of daily activities, during sleep. Conclusions 1. Atypical seizures, for instance, seizures without EEG evolution, are not rare but likely to be overlooked. 2. FBDS is closely linked with epileptic seizures, revealing FBDS to be a part of epileptic attacks. 3. HMs could expand the spectrum of motor manifestations, overlapping with sleep disorders. 4. The high prevalence of these motor events might be due to the disrupted cortical-subcortical network, which is critical in motor control and sleep.

Background Although antibody-mediated immune responses are considered pathogenic and responsible for neural injury in anti-leucine-rich glioma-inactivated protein 1 (anti-LGI1) encephalitis, previous studies have indicated that cytokines and chemokines might play roles in the pathogenic process by serving as B cell enhancers. In this study, we detected the profiles of cytokines and chemokines in the cerebral fluid (CSF) and serum of patients with anti-LGI1 encephalitis to identify potential biomarkers. Methods Sixteen patients diagnosed with anti-LGI1 encephalitis and nine patients diagnosed with noninflammatory neurologic disorders were included in the study. Cytokines and chemokines including IL-6, IL-10, IL-17, CXCL12, CXCL13, BAFF and HMGB1 in serum and CSF were measured. Results The serum and CSF levels of CXCL13 were significantly higher in patients with anti-LGI1 encephalitis (36.32±34.71 pg/mL and 2.23±2.41 pg/mL, respectively) than in controls (10.84±5.02 pg/mL and 0.34±0.21 pg/mL, respectively). There was no significant difference in serum or CSF levels of IL-6, IL-10, IL-17, CXCL12, BAFF and HMGB1 between the two groups. Conclusion CXCL13 is a potential biomarker of active inflammation in anti-LGI1 encephalitis. The distinctive response of cytokines and chemokines might be closely linked to the mechanisms underlying this condition.

Purpose Late-onset epilepsy due to autoimmune dysfunction has been reported. However, definitive diagnosis requires positive antibody results. As a result, patients with negative antibody results, but presenting with classical manifestation of autoimmune epilepsy, may be managed as suspected cases. In this study, we aim to isolate and profile the concentration of cytokines/chemokines in the cerebrospinal fluid (CSF) and the serum to ascertain if they could act as alternative diagnostic biomarkers. Patients and Methods Twenty patients aged ≥50 years were considered in this study. Ten patients were diagnosed with suspected autoimmune epilepsy (sAE) based on clinic manifestation, electroencephalogram, magnetic resonance imaging, and with negative antibody results of the serum and the CSF. The equivalent control group exhibited neurological disorders due to non-inflammatory pathologies. Serum and CSF were analyzed for cytokines/chemokines concentration, including interleukin (IL)-6, IL-10, IL-17, chemokine (C-X-C motif) ligand (CXCL)12 and CXCL13, as well as high-mobility group box protein 1 (HMGB1) and B cell activation factor (BAFF)). Results The CSF levels of IL-6, IL-17, HMGB1, and CXCL12 were significantly higher in the sAE group than in the control group. There was no difference in the CSF levels of IL-10, CXCL13 and BAFF. The serum levels of HMGB1 and CXCL12 were elevated in the sAE group compared with the control group, and there was no statistical difference in the serum levels of IL-6, IL-10, IL-17, CXCL13, and BAFF between the two groups. Conclusion Our study shows that cytokines/chemokines may act as alternative biomarkers for diagnosis of sAE. The activation of both HMGB1/CXCL12-mediated immunity and T helper cells 17 (Th17) cells may be playing a central role in the pathogenesis of sAE. We suggest that cytokines/chemokines be treated as adjuvant biomarkers, instead of solely relying on antibody screening test. However, a larger cohort in a prospective approach is required to validate our findings.

Background Painful ophthalmoplegia can be caused by various etiologies, and broad differential diagnosis is needed. Carotid-cavernous fistula (CCF) is a rare cause of painful ophthalmoplegia, and early diagnosis is quite difficult. Case presentation Here, we present a case of paroxysmal painful ophthalmoplegia caused by CCF. The episodic symptoms were nonstereotypical and lasted minutes to hours. Magnetic resonance imaging (MRI) and computed tomography angiography (CTA) results were normal, which confounded efforts to determine a diagnosis. Subsequently, digital subtraction angiography (DSA) revealed a posterior-draining CCF. The CCF was treated at an early stage without residual symptoms. Conclusions We propose that symptoms could be relapsing or remitting during an early stage of CCF and that posterior-draining CCF is prone to misdiagnosis due to atypical manifestations. Normal CTA results cannot exclude carotid-cavernous fistula, and DSA should be performed once CCF is suspected.

This study aimed to study the protective effect of (2R,4R)-4-aminopyrrolidine-2,4-dicarboxylate (2R,4R-APDC), a selective metabotropic glutamate receptor agonist, against hippocampal neuronal apoptosis induced by seizures in a rat model of pilocarpine-induced epilepsy. The Morris water maze test was used to assess the spatial memory abilities of epileptic rats with or without 2R,4R-APDC treatment. TUNEL assay was performed to examine neuronal apoptosis in hippocampus. Western blot was conducted to evaluate changes in the levels of caspase-3 and caspase-9 in hippocampus. Real-time PCR was used to determine the levels of microRNA-128 (miR-128) in hippocampus. The results of the Morris water maze test showed that the 2R,4R-APDC treatment reduced the escape latencies and swimming lengths of rats after seizures. The TUNEL assay showed that 2R,4R-APDC significantly counteracted seizure-induced cell apoptosis. The western blot confirmed this finding, demonstrating that the levels of cleaved caspase-3 and cleaved caspase-9 were potently decreased by 2R,4R-APDC in rat hippocampus after seizures. In addition, 2R,4R-APDC upregulated miR-128 expression levels in the hippocampus. A miR-128 mimic or inhibitor decreased or increased the percentage of TUNEL-positive cells in rats after seizures and 2R,4R-APDC treatment, respectively. The levels of both cleaved caspase-3 and cleaved caspase-9 were decreased in hippocampus exposed to the miR-128 mimic, whereas they were markedly increased in miR-128 inhibitor-treated hippocampus. In conclusion, 2R,4R-APDC protected hippocampal cells from cell apoptosis after seizures, possibly by upregulating miR-128.

Temporal lobe epilepsy is characterized by spontaneous recurrent seizures (SRS) and associated with behavioral problems. However, the molecular mechanisms underlying these problems are not yet clear. In this study, kainic acid (KA) was systemically administered to immature male Wistar rats to induce SRS. The behavior of the immature rats was evaluated with a water maze, elevated-plus mazes, and open field tests. The expression patterns of synaptophysin, SNAP-25, and synaptotagmin 1 (Syt 1) were examined by reverse-transcriptase polymerase chain reaction (RT-PCR) and Western blot analysis. KA-treated rats with SRS demonstrated learning and memory deficits, reduced anxiety, and increased locomotor activity, compared with placebo-treated rats and KA-treated rats without SRS. No neuronal cell loss was observed in the hippocampus 6 weeks after exposure to KA. However, RT-PCR and Western blot analyses revealed decreased synaptophysin, SNAP-25, and Syt 1 expression in KA-treated rats with SRS. Synaptophysin, SNAP-25, and Syt1 expression levels were found to be positively correlated with learning and memory but negatively correlated with anxiety and locomotor activity. These data suggested that SRS may induce changes in synaptophysin, SNAP-25, and Syt1 expression and may be functionally related to SRS-induced behavioral deficits.

Parkinson's disease (PD) is characterized by the loss of neuromelanin (NM)-containing neurons in the substantia nigra pars compacta (SNc), and it is divided into two motor subtypes: the postural instability gait difficulty (PIGD) and the tremor dominant (TD) subtypes. With NM-sensitive Magnetic Resonance Imaging (NM-MRI), investigators have been able to accurately detect signal attenuation in SNc of PD; however, the difference of NM loss between PIGD and TD subtypes is still unclear. Thus, the aim of this study was to evaluate the differences in NM-MRI between PD motor subtypes. PD patients were classified into PIGD (n=14) and TD groups (n=9); 20 age and sex matched controls were recruited. We compared the signal intensity contrast ratios in medial and lateral regions of the SNc using NM-MRI in PIGD, TD, and controls, respectively. Remarkable signal attenuation was observed in the lateral part of SNc in PD when compared with the controls, and we were able to detect more severe signal attenuation in the medial part of SNc in PIGD patients in comparison with that in the TD group. Also, the medial part of SNc, ipsilateral to the most clinically affected side, showed the highest power to discriminate the PD motor subtypes (AUC, 81%; sensitivity, 71.4%; specificity, 77.8%). Our results indicated a potential diagnostic value of NM-MRI to discriminate the PD motor subtypes, providing new evidence for the neuropathology-based differences between the two subtypes.

Mitochondrial dysfunction has been suggested to be a contributing factor of epilepsy, but the underlying mechanisms are not completely explored. Mitochondrial biogenesis is involved in regulation of mitochondrial content, morphology, and function. In the current study, we show mitochondrial biogenesis severely impaired in hippocampi of rats with chronic seizures induced by pilocarpine, as evidenced by decreased mitochondrial DNA (mtDNA) content and decreased mtDNA-encoded protein level. Furthermore, we show mtDNA transcription and replication reduced in rats with chronic seizures. These defects were independent of downregulation of mitochondrial biogenesis-related factors, such as peroxisome proliferator-activated receptor gamma coactivator-1α, nuclear respiratory factor-1, and mitochondrial transcription factor A (Tfam), but depended on reduced Tfam–DNA binding activity. The present study suggests novel mechanisms for mitochondrial dysfunction during chronic seizures.

Peroxisome proliferator-activated receptor (PPAR) γ coactivator 1-α (PGC-1α) is a transcriptional coactivator identified as an upstream regulator of lipid catabolism, mitochondrial number and function. PGC-1α protects neurons against oxidative damage by inducing several members of the mitochondrial antioxidant system such as superoxide dismutase 2 (SOD2) and uncoupling protein 2 (UCP2). Its role in seizure-induced oxidative stress has not been studied. Here we showed that pilocarpine-induced status epilepticus (SE) stimulates the PGC-1α/mitochondrial antioxidant system signaling pathway in the rat hippocampus. Because nitric oxide (NO) is the key factor of mitochondrial biogenesis through the transcriptional induction of PGC-1α, we investigated whether NO is involved in activation of the PGC-1α/mitochondrial antioxidant system after SE. Treatment with the NO synthase (NOS) inhibitor N(G)-nitro-l-argininemethyl ester (l-NAME) attenuated the increased expression of the PGC-1α/mitochondrial antioxidant system after SE and enhanced oxidative stress. These results suggest that SE can induce the PGC-1α/mitochondrial antioxidant system signaling pathway, which may represent a protective mechanism against SE-induced oxidative stress. Furthermore, NO may positively regulate the mitochondrial antioxidant system by inducing PGC-1α in pilocarpine-induced SE.

Valproic acid (VPA), a widely prescribed drug for seizures and bipolar disorder, induces apoptosis in microglia, but the underlying mechanism by which microglia apoptosis in response to VPA is not yet known. In this study, we found that the mitochondrial pathway played an important role in VPA-induced apoptosis in both BV-2 microglia and mouse primary microglial cells. In addition, VPA increased the level of phospho-p38 mitogen-activated protein kinase (MAPK), but had no effects on phospho-ERK and phospho-JNK MAPKs. Moreover, p38 inhibitor SB203580 strongly inhibited VPA-induced apoptosis and caspase-3 activation. Taken together, our results clearly demonstrated that VPA could induce apoptosis of microglia via p38 MAPK and mitochondrial apoptosis pathway.

Oxidative damage to mitochondrial DNA (mtDNA) has been implicated as an important mechanism underlying mitochondrial deficiency in epileptic seizures. In focusing on the role of the DNA repair pathway, we determined the response of the mitochondrial base excision repair (mtBER) pathway in pilocarpine-induced status epilepticus (SE) in hippocampi of male Wistar rats. The expression of 8-oxoguanine DNA glycosylase (OGG1) and polymerase gamma (polgamma) was decreased at both the cellular mRNA and mitochondrial protein levels at 3, 9 and 25h after the onset of SE. The mRNA and protein levels of APE1 were maintained, but the mitochondrial protein level decreased at 3 and 9h and recovered at 25h. Therefore, the mtBER pathway failed to respond to SE induced by pilocarpine. The failure of mitochondrial import might be an important factor responsible for the lowered mtBER enzymes in mitochondria. We hypothesize that the down-regulation of mtBER enzymes may aggravate mtDNA damage and mitochondrial deficiency after the onset of SE.

Seizures and status epilepticus induce an excessive production of reactive oxygen species leading to oxidative stress. Vitamin E, a classic antioxidant, has a neuroprotective effect on rats with seizures by regulating reactive oxygen species production. The activity of chaperone-mediated autophagy, a selective pathway for the degradation of cytosolic proteins in lysosomes, is enhanced during oxidative stress. Whether chaperone-mediated autophagy is induced during status epilepticus is not established. To address this problem, we used pilocarpine to elicit status epilepticus in rats. Lysosome-associated membrane protein 2a was used to estimate chaperone-mediated autophagy. We showed that compared to control animals, lysosome-associated membrane protein 2a at lysosomal membranes increased significantly in rats at 8 h, 16 h, and 24 h after induction of status epilepticus, which directly correlated with chaperone-mediated autophagy activity. Since reactive oxygen species are believed to be important in the pathogenesis of status epilepticus and are essential for the process of chaperone-mediated autophagy, we also sought to determine if pretreatment with vitamin E reduced chaperone-mediated autophagy. Pretreatment with vitamin E reduced oxidative stress and partially inhibited chaperone-mediated autophagy in brain at 24 h after status epilepticus versus vehicle. Taken together, these data show that chaperone-mediated autophagy is increased in rats with pilocarpine-induced status epilepticus through upregulation of de novo synthesis of lysosome-associated membrane protein 2a. Antioxidants such as vitamin E may partially inhibit activated chaperone-mediated autophagy.

Autophagy, a process of bulk degradation of cellular constituents through autophagosome-lysosomal pathway, is enhanced during oxidative stress. Whether autophagy is induced during status epilepticus (SE), which induces an excess production of reactive oxygen species (ROS) and leads to oxidative stress, is not established. We also sought to determine if pretreatment with Vitamin E reduced autophagy. We used pilocarpine to elicit SE in rats. The ratio of LC3 II to LC3 I and beclin 1 were used to estimate autophagy. We found that ratio of LC3 II to LC3 I and beclin 1 increased significantly at 2, 8, 16, 24 and 72 h, peaking at 24 h after SE onset. Pretreatment with Vitamin E partially inhibited autophagy by reducing LC3 II formation and de novo synthesis of beclin 1 at 24 h after seizures. These data show that autophagy is increased in rats with pilocarpine-induced SE, and Vitamin E have a partial inhibition on autophagy.

Intense poly(ADP-ribose) polymerase-1 (PARP-1) activation was implicated as a major cause of caspase-independent cell death in the hippocampal neuronal culture (HNC) model of acute acquired epilepsy (AE). The molecular mechanisms are quite complicated. The linkage among neuronal death, cellular nicotinamide adenine dinucleotide (NAD) levels, apoptosis-inducing factor (AIF) translocation, SIRT1 expression and activity were investigated here. The results showed that PARP-1 over-activation caused by Mg²⁺-free stimuli led to cellular NAD depletion which could block AIF translocation from mitochondria to nucleus and attenuate neuronal death. Also, SIRT1 deacetylase activity was reduced by Mg²⁺-free treatment, accompanied by elevated ratio of neuronal death, which could be rescued by NAD repletion. These data demonstrated that cellular NAD depletion and decline of SIRT1 activity play critical roles in PARP-1-mediated epileptic neuronal death in the HNC model of acute AE.

Inhibition of poly(ADP-ribose) polymerase (PARP) has been proposed to have a neuroprotective effect on hippocampal neurons in animal models of epilepsy. However, the mechanisms of PARP-mediated epileptic neuron apoptosis in vitro are still not thoroughly understood. Therefore, we investigated the effect of PARP inhibition and the underlying mechanisms in the hippocampal neuronal culture model of acquired epilepsy which is generally accepted as the neuronal culture model of spontaneous seizure discharge in vitro. As a result, PARP was activated and the administration of 3,4-dihydro-5-[4-(1-piperidinyl)butoxy]-1(2H)-isoquinolinone (DPQ), an inhibitor of PARP, significantly decreased the percentage of neuron apoptosis induced by Mg(2+)-free treatment. Western blot and confocal laser scanning microscopy (CLSM) analysis showed that DPQ increased the phosphorylation of Akt and attenuated mitochondria-nucleus translocation of the apoptosis-inducing factor (AIF). Furthermore, wortmannin, an inhibitor of PI-3K, inhibited the translocation of AIF to the nucleus. The results of the present study demonstrated that the inhibition of PARP might have therapeutic value in seizure-induced hippocampal neuron damage in vitro via suppressing Akt-mediated AIF translocation.

Diazoxide (DZ), a highly selective opener of the mitochondrial ATP-sensitive potassium (mitoK(ATP)) channel, has neuroprotective effects. However, the mechanism of DZ protecting hippocampal neurons against cell death in pilocarpine-induced seizures is unknown. In this study, we investigated DZ attenuating neuronal loss caused by pilocarpine-induced seizures in rat hippocampus. DZ inhibited seizure-induced change in phospho-Akt expression, translocation of apoptosis-inducing factor (AIF), release of cytochrome c (CytC) and caspase-3 activation, which could be abolished by preincubation with 5-hydroxydecanoic acid, an inhibitor of mitoK(ATP). In addition, wortmannin, an inhibitor of phosphatidylinositol-3-kinase (PI3K), attenuated the translocation of AIF, CytC release and caspase-3 activation after seizures. DZ could reduce neuronal death induced by seizures in hippocampus by suppressing the translocation of AIF, CytC release and the activation of caspase-3 via the PI3K/Akt pathway.

In this study, we demonstrated a decreased level of mitochondrial DNA (mtDNA) with a large number of oxidized bases in hippocampi of rats with epilepsy induced by pilocarpine. In order to verify the underlying mechanism of mtDNA impairment, we detected the response of antioxidant defense system and mitochondrial base excision repair (mtBER) pathway. Superoxide dismutase2 (SOD-2) and glutathione (GSH) were significantly decreased in the experimental group, manifesting a decreased capacity of scavenging free radicals. Mitochondrial base excision repair (mtBER) pathway, which is the main repair pathway for the removal of oxidative base modifications, displayed unbalanced expression in epileptic group. DNA polymerasegamma (polgamma) increased, while apurinic/apyrimidinic endonuclease (APE1), one of mtBER initiators, decreased in mitochondria in the chronic phase of epileptogenesis. In conclusion, mtDNA was impaired during chronic recurrent seizures, whereas the endogenous antioxidants and the mtBER pathway failed to respond to the elevated mtDNA damage.

Ghrelin, a 28-amino-acid peptide, is mainly secreted by the stomach. Evidence has shown ghrelin to have neuroprotective effects. However, whether ghrelin protects hippocampal neurons against cell death in pilocarpine-induced seizures is unknown. We used Nissl staining to show that ghrelin attenuated the neuronal loss caused by pilocarpine-induced seizures in the hippocampus. Ghrelin exerted the protective action through regulating the phosphatidylinositol-3-kinase and Akt pathway. Moreover, ghrelin treatment reversed the decreased ratio of Bcl-2 to Bax induced by seizures while inhibiting the activated caspase-3. Ghrelin can inhibit hippocampal neuronal damage caused by pilocarpine-induced seizures, which might have therapeutic value in seizures.