Project description:The epilepsies represent one of the most common neurological disorders. Mesial temporal lobe epilepsies (MTLE) are the most frequent form of partial epilepsies and display frequent resistance to anti-epileptic drugs thus representing a major health care problem. In TLE, the origin of seizure activity typically involves the hippocampal formation, which displays major neuropathological features, described with the term hippocampal sclerosis (HS). HS is the most frequent pathological substrate of refractory mesial temporal lobe epilepsy. Complex partial seizures (CPS) are the predominant seizure type associated with medial temporal lobe epilepsy. MTLE is commonly due to mesial temporal sclerosis (MTS). The biology underlying the epilepstic seizures and the transcriptome associated to the seizure in intractable medial temporal lobe epilepsy is ill understood. The aim of the study was to identify potential biomarkers that could identify epileptic seizure. Thus we performed transcriptome profiling of ten medial temporal lobe epilepsy cases which are resistant to the drug and underwent temporal lobectomy. The cases constitutes of patients with intractable complex partial seizure, treated medically and have undergone detailed presurgical evaluation and subjected to surgery for standard temporal lobectomy and amygdalo-hippocampectomy. The spiking areas identified after the electrocorticography will form the test tissues, which compared with the nonspiking areas removed during the surgery, from the same patient. This could probably form one of the appropriate controls, as test and control are from same patient, which eliminates the genome variations that could incur due to the comparison with the tissues from the another patient. Also this could get rid of expression changes due to the treatments undergone by the patient. We performed two color microarray wherein we labled seizure focus (spiking area) with Cy5 and non-seizure region tissues (non-spiking) with Cy3. As a strategy to test the possibility of potential diagnostic biomarkers we are intended to test the differentially regulated molecules in an independent set of epilepsy samples. Two color experiment
Project description:The epilepsies represent one of the most common neurological disorders. Mesial temporal lobe epilepsies (MTLE) are the most frequent form of partial epilepsies and display frequent resistance to anti-epileptic drugs thus representing a major health care problem. In TLE, the origin of seizure activity typically involves the hippocampal formation, which displays major neuropathological features, described with the term hippocampal sclerosis (HS). HS is the most frequent pathological substrate of refractory mesial temporal lobe epilepsy. Complex partial seizures (CPS) are the predominant seizure type associated with medial temporal lobe epilepsy. MTLE is commonly due to mesial temporal sclerosis (MTS). The biology underlying the epilepstic seizures and the transcriptome associated to the seizure in intractable medial temporal lobe epilepsy is ill understood. The aim of the study was to identify potential biomarkers that could identify epileptic seizure. Thus we performed transcriptome profiling of ten medial temporal lobe epilepsy cases which are resistant to the drug and underwent temporal lobectomy. The cases constitutes of patients with intractable complex partial seizure, treated medically and have undergone detailed presurgical evaluation and subjected to surgery for standard temporal lobectomy and amygdalo-hippocampectomy. The spiking areas identified after the electrocorticography will form the test tissues, which compared with the nonspiking areas removed during the surgery, from the same patient. This could probably form one of the appropriate controls, as test and control are from same patient, which eliminates the genome variations that could incur due to the comparison with the tissues from the another patient. Also this could get rid of expression changes due to the treatments undergone by the patient. We performed two color microarray wherein we labled seizure focus (spiking area) with Cy5 and non-seizure region tissues (non-spiking) with Cy3. As a strategy to test the possibility of potential diagnostic biomarkers we are intended to test the differentially regulated molecules in an independent set of epilepsy samples.
Project description:This study was performed to test the hypothesis that systemic leukocyte gene expression has prognostic value differentiating low from high seizure frequency refractory temporal lobe epilepsy (TLE). A consecutive series of sixteen patients with refractory temporal lobe epilepsy was studied. Based on a median baseline seizure frequency of 2.0 seizures per month, low versus high seizure frequency was defined as < 2 seizures/month and > 2 seizures/month, respectively.
Project description:Analysis of biopsy hippocampal tissue of patients with pharmacoresistant temporal lobe epilepsy (TLE) undergoing neurosurgical removal of the epileptogenic focus for seizure control. Chronic TLE goes along with focal hyperexcitability. Results provide insight into molecular mechanisms that may play a role in seizure propensity
Project description:Analysis of biopsy hippocampal tissue of patients with pharmacoresistant temporal lobe epilepsy (TLE) undergoing neurosurgical removal of the epileptogenic focus for seizure control. Chronic TLE goes along with focal hyperexcitability. Results provide insight into molecular mechanisms that may play a role in seizure propensity 150 human hippocampus samples
Project description:Temporal lobe epilepsy (TLE) is the most common intractable form of epilepsy in adults and status epilepticus (SE) is the most severe form of seizure that can be non-convulsive and is then difficult to diagnose. Diagnosis of both conditions is principally based on clinical examination and history, often depending on EEG and imaging. A molecular biomarker of these two conditions would be transformational in supporting both diagnoses.Cerebrospinal fluid offers an alternative source of microRNA biomarkers with the advantage of being in closer contact with the target tissue and sites of pathology. The present study indicates cerebrospinal fluid may contain microRNA biomarkers of TLE and SE and offers insights into trafficking mechanisms of biofluid microRNAs that may further enhance diagnostic value.
Project description:Epilepsy is characterized by hypersynchronous neuronal discharges, which are associated with an increased cerebral metabolic rate of oxygen and ATP demand. Uncontrolled seizure activity (status epilepticus) results in mitochondrial exhaustion and ATP depletion, which potentially generate energy mismatch and neuronal loss. Many cells can adapt to increased energy demand by increasing metabolic capacities. However, acute metabolic adaptation during epileptic activity and its relationship to chronic epilepsy remains poorly understood. We elicited seizure-like events (SLEs) in an in vitro model of status epilepticus for eight hours. Electrophysiological recording and tissue oxygen partial pressure recordings were performed. After eight hours of ongoing SLEs, we used proteomics-based kinetic modeling to evaluate changes in metabolic capacities. We compared our findings regarding acute metabolic adaptation to published proteomic and transcriptomic data from chronic epilepsy patients. Epileptic tissue acutely responded to uninterrupted SLEs by upregulating ATP production capacity. This was achieved by a coordinated increase in the abundance of proteins from the respiratory chain and oxidative phosphorylation system. In contrast, chronic epileptic tissue shows a 25-40% decrease in ATP production capacity. In summary, our study reveals that epilepsy leads to dynamic metabolic changes. Acute epileptic activity boosts ATP production, while chronic epilepsy reduces it significantly.
Project description:Epilepsy is a disorder that affects around 1% of the population. Epilepsy is widely controlled by anti-convulsant drugs; however, approximately one third of patients do not respond to this treatment. In many cases of drug resistant epilepsy (DRE) surgical removal of the indicated tissue may be performed to decrease seizure burden. Mitochondrial damage and oxidative stress has been implicated in epilepsy suggesting that alternation in both energy metabolism and redox balance are critical to seizure onset. To understand the underlying biological processes involved in DRE, a combination of proteomics and metabolomics strategies together with oxidative damage assessment were used to compare molecular differences and enzymatic activities in tissue implicated in seizure onset to tissue with no abnormal activity within patients. Label free quantitation identified 17 proteins with altered abundance in the seizure onset zone as compared to tissue with normal activity. Assessment of oxidative protein damage by protein carbonylation identified additional 11 proteins with potentially altered function in the seizure onset zone. Pathway analysis revealed that most of the affected proteins are involved in energy metabolism and redox balance. Further enzymatic assays showed significantly decreased activity of transketolase (TKT) indicating a disruption of the Pentose Phosphate Pathway and diversion of intermediates into purine metabolic pathway, resulting in the generation of the potentially pro-convulsant metabolites. Altogether, these findings suggest that imbalance in energy metabolism and redox balance, pathways critical to proper neuronal function, play important roles in neuronal network hyperexcitability and can be used as a primary target for potential therapeutic strategies to combat DRE.
Project description:Epilepsy frequently develops as a result of brain insult, for example brain injury or stroke. Currently there are no tools allowing us to predict which trauma patients will eventually develop epilepsy. There is evidence that microRNAs levels are altered in plasma, making them attractive candidates for peripheral biomarkers of epilepsy. We analyzed miRNA levels in plasma samples using Affymetrix microarrays 4.1 and performed comparative analysis of samples. We performed 3 comparisons: i) control animals vs. Status epilepticus animals, ii) animals which developed first spontaneous seizure around 7 days post stimulation (EARLY), or later after 21days post stimulation (LATE), iii) animals that had developed seizures at given timepoint (EPI) and animals that did not experience seizures by given timepoint (NONEPI).
Project description:Pediatric epilepsy is a neurological condition that causes repeated and unprovoked seizures and is more common in 1–5-year-old children. Drug resistance has been indicated as a key challenge in improving the clinical outcomes of patients with pediatric epilepsy. In the present study, we aimed to identify serum small extracellular vesicles (sEVs) derived microRNAs (miRNAs) from the serum samples of children for predicting the prognosis in patients with epilepsy and drug-resistant epilepsy