Combination antioxidant therapy prevents epileptogenesis and modifies chronic epilepsy.
Ontology highlight
ABSTRACT:
SUBMITTER: Shekh-Ahmad T
PROVIDER: S-EPMC6692059 | biostudies-literature | 2019 Sep
REPOSITORIES: biostudies-literature
Publications
Combination antioxidant therapy prevents epileptogenesis and modifies chronic epilepsy.
Shekh-Ahmad Tawfeeq T Lieb Andreas A Kovac Stjepana S Gola Lukas L Christian Wigley W W Abramov Andrey Y AY Walker Matthew C MC
Redox biology 20190719
Many epilepsies are acquired conditions following an insult to the brain such as a prolonged seizure, traumatic brain injury or stroke. The generation of reactive oxygen species (ROS) and induction of oxidative stress are common sequelae of such brain insults and have been shown to contribute to neuronal death and the development of epilepsy. Here, we show that combination therapy targeting the generation of ROS through NADPH oxidase inhibition and the endogenous antioxidant system through nucle ...[more]
Similar Datasets
Project description:Mesial temporal lobe epilepsy (MTLE) is the most common type of focal seizure disorder. In MTLE, seizures typically originate from a sclerotic hippocampus. Approximately one-third of patients do not respond to anti-seizure drugs and have few effective therapeutic options. Surgery to resect or ablate the affected temporal lobe is one such option, but it is not indicated or adequate for all individuals and can have adverse effects. Here, we report the development of an alternative cell therapy strategy for drug-resistant MTLE. The cell therapeutic is derived from a clinical-grade human embryonic stem cell line, and composed of cryopreserved post-mitotic medial ganglionic eminence (MGE)-type GABAergic inhibitory neurons of a predominantly pallial interneuron lineage. Single-dose intrahippocampal delivery of cryopreserved human pallial interneurons in a chronic mouse model of drug-resistant MTLE resulted in consistent and stable suppression of mesiotemporal seizures, with most animals becoming seizure-free. The grafted human interneurons distributed locally, matured, and persisted in the sclerotic hippocampus throughout the 8.5-month study. Pathological hallmarks of MTLE, such as hippocampal granule cell dispersion and sclerosis, were significantly reduced, and epileptic animal survival rates increased, after administration of the human interneurons. Suppression of seizure activity and amelioration of neuropathology were dose-dependent and suggested a broad therapeutic dosing range. No ectopic tissue or teratoma formation was detected after cell transplantation. Furthermore, behavioral abnormalities were not observed at any dose on a battery of assays. These findings support further development of human pallial MGE-type GABAergic interneuron cell therapy for the treatment of drug-resistant focal epilepsies.
2023-10-10 | GSE208672 | GEO
Project description:The importance of comorbidities in determining the quality of life of individuals with epilepsy and their families has received increasing attention in the past decade. Along with it has come a recognition that in some individuals, certain comorbidities may have preexisted, and may have contributed to their developing epilepsy. Many mechanisms are capable of interconnecting different dysfunctions that manifest as distinct disorders, often diagnosed and managed by different specialists. We review the human data from the perspective of epidemiology as well as insights gathered from neurodiagnostic and endocrine studies. Animal studies are reviewed to refine our mechanistic understanding of the connections, because they permit the narrowing of variables, which is not possible when studying humans.
| S-EPMC4930916 | biostudies-literature
Project description:Neuropathological features of Alzheimer's disease (AD) are recapitulated in transgenic mice expressing familial AD-causing mutations, but ectopic transgene overexpression makes it difficult to relate these abnormalities to disease pathogenesis. Alternatively, the APP/PS-1 double knock-in (DKI) mouse produces mutant amyloid precursor protein (APP) and presenilin-1 (PS-1) with normal levels and regulatory controls. Here, we investigated effects of amyloid on brain structure and neuroplasticity by vaccinating DKI mice with amyloid-β starting at 8 months of age. At 14 months, vaccination blocked cerebral amyloid deposition and its attendant microglial activation. Neuropil abnormalities were pronounced only within plaques, and included circumscribed loss and dysmorphology of axons, dendrites, terminals and spines. Blockade of amyloid deposition restored neuropil integrity. Amyloid removal did not rescue reductions in the hippocampal neural progenitor and neuroblast populations, but adding 1 month of voluntary exercise to amyloid-β vaccination markedly stimulated hippocampal neurogenesis. These results identify amyloid-dependent and -independent structural changes in the DKI mouse model of AD. Combining exercise with amyloid-directed immunotherapy produces greater restoration of brain structure and neuroplasticity than is achieved with either maneuver alone.
| S-EPMC3094748 | biostudies-literature
Project description:This article highlights the emerging therapeutic potential of specific epigenetic modulators as promising antiepileptogenic or disease-modifying agents for curing epilepsy. Currently, there is an unmet need for antiepileptogenic agents that truly prevent the development of epilepsy in people at risk. There is strong evidence that epigenetic signaling, which exerts high fidelity regulation of gene expression, plays a crucial role in the pathophysiology of epileptogenesis and chronic epilepsy. These modifications are not hard-wired into the genome and are constantly reprogrammed by environmental influences. The potential epigenetic mechanisms, including histone modifications, DNA methylation, microRNA-based transcriptional control, and bromodomain reading activity, can drastically alter the neuronal gene expression profile by exerting their summative effects in a coordinated fashion. Such an epigenetic intervention appears more rational strategy for preventing epilepsy because it targets the primary pathway that initially triggers the numerous downstream cellular and molecular events mediating epileptogenesis. Among currently approved epigenetic drugs, the majority are anticancer drugs with well-established profiles in clinical trials and practice. Evidence from preclinical studies supports the premise that these drugs may be applied to a wide range of brain disorders. Targeting histone deacetylation by inhibiting histone deacetylase enzymes appears to be one promising epigenetic therapy since certain inhibitors have been shown to prevent epileptogenesis in animal models. However, developing neuronal specific epigenetic modulators requires rational, pathophysiology-based optimization to efficiently intercept the upstream pathways in epileptogenesis. Overall, epigenetic agents have been well positioned as new frontier tools towards the national goal of curing epilepsy.
| S-EPMC5565684 | biostudies-literature
Project description:Currently available epilepsy drugs only affect the symptoms (seizures), and there is a need for innovative treatments that target the underlying disease. Increasing evidence points to inflammation as a potentially important mechanism in epileptogenesis. In the last decade, a new generation of etiologically realistic syndrome-specific experimental models have been developed, which are expected to capture the epileptogenic mechanisms operating in corresponding patient populations, and to exhibit similar treatment responsiveness. Recently, an intervention known to have broad-ranging anti-inflammatory effects (selective brain cooling) has been found to prevent the development of spontaneously occurring seizures in an etiologically realistic rat model of post-traumatic epilepsy. Several drugs used clinically for other indications also have the potential for inhibiting inflammation, and should be investigated for antiepileptogenic activity in these models. If results of such studies are positive, these compounds could rapidly enter Phase III trials in patients at high risk of developing epilepsy.
| S-EPMC4264793 | biostudies-literature
Project description:Epilepsy is a major neurological disorder that affects approximately 1% of the population. The processes that lead to the development of epilepsy (epileptogenesis) are largely unknown. Levetiracetam is a novel antiepileptic drug (AED) that in the kindling model inhibits epileptogenesis in addition to being effective in controlling established epilepsy. The mechanisms of action of levetiracetam as an AED and an antiepileptogenic drug are unknown. By identifying the effect of chronic levetiracetam therapy on gene expression in the brain we hope to be able to identify genes that are involved in epileptogenesis. By comparing the gene expression profiles of levetiracetam and phenytoin treatments, we hope to be able to distinguish between genes that are important for the antiepileptic (anti-seizure) effect and genes that are important for the antiepileptogenic effect of levetiracetam. Phenytoin is a well-established AED; its mechanism of action involves inhibition of sodium channels. In contrast to levetiracetam, available data suggest that phenytoin in certain situations may enhance rather than inhibit the development of epilepsy. ,We will identify changes in gene expression in the hippocampus, frontal cortex, and brain stem caused by chronic treatment (3 months) with levetiracetam or phenytoin. We will search for differences in the gene expression profiles after chronic treatment with the two drugs, to explain the different clinical effects of the two drugs.,We hypothesize that chronic treatment with levetiracetam leads to changes in the expression of genes that are involved in both the antiepileptogenetic and antiepileptic effect of the drug, whereas chronic treatment with phenytoin affects genes that may be related to pro-epileptogenetic as well as antiepileptic effects of that drug. We further hypothesize that i) regional differences in the effects of levetiracetam and phenytoin may reflect important functional differences in the actions of these two drugs, and ii) there may be different mechanisms involved in their anti-seizure effect. Male Wistar rats receive levetiracetam (150 mg/kg x 2), phenytoin (75 mg/kg x 2) or control solution (N=7 in each group) through a gastric tube twice daily for 90 days. Experimental animals and controls are housed together in the same cages in groups of three, facilitating paired comparisons among the three groups in animals that have experienced the same environment throughout the 3 month experimental period. Four hrs after the last dose animals are anesthetized, decapitated, and total RNA is extracted from brain stem, frontal cortex, and hippocampus. RNA will be sent to the TGEN facility for hybridization to the rat U230A chips. The number of chips needed is (2 drugs + 1 control) * (3 brain regions) * (7 animals per group) = 63 chips. We will initially select those genes for analysis that are called present by the Affymetrix software in 4 or more animals for at least one of the 6 experimental groups. Then t-tests with Benjamini & Hochberg correction for protection against multiple comparisons will be used to identify genes that are differentially expressed at a false discovery rate of .05 among any of the six groups. We will be primarily interested in the following expression profiles, analyzed as paired comparisons by the Affymetrix software: 1. phenytoin vs control in hippocampus, 2. phenytoin vs control in brain stem, 3. levetiracetam vs control in hippocampus, 4. levetiracetam vs control in brain stem. We will then compare the profiles of both drugs in each brain region (e.g. phenytoin vs levetiracetam in hippocampus) to select genes that are drug-specific. We will also take a Venn diagram approach to identify genes that are drug-specific across both brain regions tested.
2007-08-01 | E-GEOD-2880 | biostudies-arrayexpress
Project description:The isolation and identification of the discrete plant cannabinoids in marijuana revived interest in analyzing historical therapeutic claims made for cannabis in clinical case studies and anecdotes. In particular, sources as old as the 11th and 15th centuries claimed efficacy for crude marijuana extracts in the treatment of convulsive disorders, prompting a particularly active area of preclinical research into the therapeutic potential of plant cannabinoids in epilepsy. Since that time, a large body of literature has accumulated describing the effects of several of the >100 individual plant cannabinoids in preclinical models of seizures, epilepsy, epileptogenesis, and epilepsy-related neuroprotection. We surveyed the literature for relevant reports of such plant cannabinoid effects and critically reviewed their findings. We found that acute CB1R agonism in simple models of acute seizures in rodents typically produces anti-convulsant effects whereas CB1R antagonists exert converse effects in the same models. However, when the effects of such ligands are examined in more complex models of epilepsy, epileptogenesis and neuroprotection, a less simplistic narrative emerges. Here, the complex interactions between (i) brain regions involved in a given model, (ii) relative contributions of endocannabinoid signaling to modulation of synaptic transmission in such areas, (iii) multi-target effects, (iv) cannabinoid type 1 and type 2 receptor signaling interactions and, (v) timing, (vi) duration and (vii) localization of ligand administration suggest that there is both anti-epileptic therapeutic potential and a pro-epileptic risk in up- and down-regulation of endocannabinoid signaling in the central nervous system. Factors such receptor desensitization and specific pharmacology of ligands used (e.g. full vs partial agonists and neutral antagonists vs inverse agonists) also appear to play an important role in the effects reported. Furthermore, the effects of several plant cannabinoids, most notably cannabidiol (CBD) and cannabidavarin (CBDV), in models of seizures, epilepsy, epileptogenesis, and neuroprotection are less ambiguous, and consistent with reports of therapeutically beneficial effects of these compounds in clinical studies. However, continued paucity of firm information regarding the therapeutic molecular mechanism of CBD/CBDV highlights the continued need for research in this area in order to identify as yet under-exploited targets for drug development and raise our understanding of treatment-resistant epilepsies. The recent reporting of positive results for cannabidiol treatment in two Phase III clinical trials in treatment-resistant epilepsies provides pivotal evidence of clinical efficacy for one plant cannabinoid in epilepsy. Moreover, risks and/or benefits associated with the use of unlicensed ?9-THC containing marijuana extracts in pediatric epilepsies remain poorly understood. Therefore, in light of these paradigm-changing clinical events, the present review's findings aim to drive future drug development for newly-identified targets and indications, identify important limitations of animal models in the investigation of plant cannabinoid effects in the epilepsies, and focuses future research in this area on specific, unanswered questions regarding the complexities of endocannabinoid signaling in epilepsy. This article is part of a Special Issue titled Cannabinoids and Epilepsy.
| S-EPMC5651410 | biostudies-literature
Project description:The long-term effects of opioids on sensitization processes are believed to be mediated through the N-methyl-D-aspartate receptor. Quantitative sensory testing (QST) changes observed after a ketamine infusion have been previously described but the effect that chronic opioids will have is not known. The results of this prospective randomized factorial trial compared the thermal QST changes observed after a .05 mg/kg ketamine infusion or a saline placebo in chronic pain subjects who were either opioid-naive or were chronically using opioids for chronic noncancer pain are presented. No baseline QST differences were noted between the 4 groups at baseline. Comparison of changes preinfusion with postinfusion QST measurements resulted in decreased average change in temporal summation response between opioid subjects who received a placebo compared with those who received a ketamine infusion (-5.22, SD = 9.96 vs 13.81, SD = 19.55; P = .004). Additionally, the average change in temporal summation was decreased among subjects who received a ketamine infusion and were not chronically using opioids compared with subjects who were using chronic opioids and received a placebo infusion (-1.91, SD = 13.25 vs 13.81, SD = 19.55; P = .007). The results indicate that low-dose ketamine infusions produce subtle changes in QST phenotypes that are modified by the chronic use of opioids. This illustrates the potential diagnostic and therapeutic value of ketamine in the setting of chronic opioid use. PERSPECTIVE:The presented data further our understanding of modulation of sensory perception in the setting of chronic opioid use and the role of the N-methyl-D-aspartate receptor. The use of low-dose ketamine infusions may be useful for the treatment as well as diagnosis of opioid-related neuropathic conditions.
| S-EPMC5729746 | biostudies-literature
Project description:In this study, we aimed to modify the immune response in the long term after allogeneic bone marrow transplantation (allo-BMT) by using the proteasome inhibitor ixazomib (IXZ) at the late stages of the post-transplant period. This approach facilitated the immune reconstitution after transplantation. IXZ significantly prolonged survival and decreased the risk of chronic graft-versus-host disease (cGvHD) in two different murine models without hampering the graft-versus-leukemia (GvL) effect, as confirmed by bioluminescence assays. Remarkably, the use of IXZ was related to an increase of regulatory T cells both in peripheral blood and in the GvHD target organs and a decrease of effector donor T cells. Regarding B cells, IXZ treated mice had faster recovery of B cells in PB and of pre-pro-B cells in the bone marrow. Mice receiving ixazomib had a lower number of neutrophils in the GvHD target organs as compared to the vehicle group. In summary, delayed administration of IXZ ameliorated cGvHD while preserving GvL and promoted a pro-tolerogenic immune response after allo-BMT.
| S-EPMC8636253 | biostudies-literature
Project description:Epilepsy is one of the most common neurological disorders, yet its pathophysiology is poorly understood due to the high complexity of affected neuronal circuits. To identify dysfunctional neuronal subtypes underlying seizure activity in the human brain, we have performed single-nucleus transcriptomics analysis of >110,000 neuronal transcriptomes derived from temporal cortex samples of multiple temporal lobe epilepsy and non-epileptic subjects. We found that the largest transcriptomic changes occur in distinct neuronal subtypes from several families of principal neurons (L5-6_Fezf2 and L2-3_Cux2) and GABAergic interneurons (Sst and Pvalb), whereas other subtypes in the same families were less affected. Furthermore, the subtypes with the largest epilepsy-related transcriptomic changes may belong to the same circuit, since we observed coordinated transcriptomic shifts across these subtypes. Glutamate signaling exhibited one of the strongest dysregulations in epilepsy, highlighted by layer-wise transcriptional changes in multiple glutamate receptor genes and strong upregulation of genes coding for AMPA receptor auxiliary subunits. Overall, our data reveal a neuronal subtype-specific molecular phenotype of epilepsy.
| S-EPMC7541486 | biostudies-literature