Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0036572 (seizures)
 80,221 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We report the development of a radioimmunoassay for prepro-TRH(160-169) (PS4), a thyrotropin-releasing hormone (TRH) enhancing peptide, and its use in characterizing the effect of electroconvulsive seizures on the levels of this peptide in various brain regions of male Wistar rats. We found that electroconvulsive seizures significantly elevated the PS4 levels in hippocampus, amygdala, pyriform (olfactory) cortex, and anterior cortex but not in striatum, motor cortex, locus ceruleus, or ventral lateral medulla. The levels of PS4 were highly correlated with the corresponding TRH (p-Glu-His-Pro-NH2) and TRH-Gly (p-Glu-His-Pro-Gly) levels in hippocampus, amygdala, and pyriform cortex, consistent with the prepro-TRH source of all of these peptides. The PS4 levels in hippocampus and amygdala were significantly correlated with the immobility time in the Porsolt forced swim test, an established animal model for antidepressant effects. The PS4 levels in peripheral blood, hypothalamus, anterior cortex, amygdala, and eyes increased severalfold at 20 min following intracisternal injection of 228 microg of this peptide, suggesting that it readily crosses the blood-brain barrier. The pituitary levels of PS4 and TRH-Gly, on the other hand, were decreased within 20 min by intracisternal PS4, suggesting PS4 stimulated the release of prepro-TRH peptides from the pituitary. Fresh rat and human serum rapidly degraded PS4, indicating that it may act primarily as a paracrine modulator of TRH effects in pituitary, brain, and reproductive system.
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PMID:Electroconvulsive seizures increase levels of PS4, the TRH-enhancing peptide [prepro-TRH(160-169)], in rat brain. 915 70

The relationship between the thyrotropin (TSH) response to thyrotropin-releasing hormone (TRH) and the duration of seizures induced by electroconvulsive therapy (ECT) in depressed patients was investigated. In a balanced-order cross-over design, 16 depressed women were given 0.4 mg TRH or placebo intravenously, 20 min before ECT in the first two sessions. In the third ECT session TRH was given just prior to ECT. Thyrotropin (TSH) levels at various sampling times, as well as the duration of seizures, were measured. There was a significant inverse correlation between plasma TSH concentrations 20 min after TRH administration (deltaTSH) and seizure duration. Furthermore, when patients were categorized according to their TSH response to TRH, the group with blunted responses (deltaTSH <6 microIU/ mL, n = 7) had a longer seizure time during ECT than the group with non-blunted responses (deltaTSH > 6 microIU/mL, n = 9). Finally, the seizure duration in the group with blunted TSH responses was reduced significantly when TRH was co-administered, while it remained unchanged in the group with non-blunted TSH responses. It is concluded that a blunted TSH response to TRH might indicate a seizure susceptibility as measured by the duration of seizures induced by ECT. The fact that TRH pre-administration had a reducing effect suggests that this substance might be involved in the pathophysiology of ECT-induced seizures.
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PMID:Blunted TSH response to TRH and seizure duration in ECT. 1006 9

Intractable seizures remain a significant therapeutic challenge despite current advances in the treatment of epilepsy. Thyrotropin-releasing hormone, the first neuroendocrine releasing factor to be isolated and fully characterized, was also the first releasing factor investigated as a possible neurotransmitter/neuromodulator outside the hypothalamus. Basic and clinical research has revealed a distinct neuroanatomic distribution and a neurochemical role for thyrotropin-releasing hormone in seizure modulation. Thyrotropin-releasing hormone and selected analogs were reported to have antiepileptic effects in several animal seizure paradigms, including kindling and electroconvulsive shock. Clinically, thyrotropin-releasing hormone treatment has been reported to be efficacious in such intractable epilepsies as infantile spasms, Lennox-Gastaut syndrome, myoclonic seizures, and other generalized and refractory partial seizures. Herein, we review evidence that suggests that thyrotropin-releasing hormone and selected thyrotropin-releasing hormone analogs may represent a new class of novel antiepileptic drugs, namely, antiepileptic neuropeptides and provide insights into potential new treatments for the intractable epilepsies.
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PMID:Thyrotropin-releasing hormone in the treatment of intractable epilepsy. 1181 29

Gene expression profiling by microarrays is a powerful tool for identification of genes that may encode key proteins involved in molecular mechanisms underlying epileptogenesis. Using the Affymetrix oligonucleotide microarray, we have surveyed the expression levels of more than 26,000 genes and expressed sequence tags (ESTs) in the amygdala-kindling model of temporal lobe epilepsy. Furthermore, the effect of the antiepileptic drug levetiracetam (LEV) on kindling-induced alterations of gene expression was studied. Treatment of rats with LEV during kindling acquisition significantly suppressed kindling development. For gene expression profiling, six groups of rats were included in the present study: (i) and (ii) sham-operated rats treated with saline or LEV; (iii) and (iv) electrode-implanted but non-kindled rats treated with saline or LEV; (v) and (vi) kindled rats treated with saline or LEV. Treatment was terminated after 11 or 12 daily amygdala stimulations, when all vehicle-treated rats had reached kindling criterion, i.e. a stage 5 seizure. Twenty-four hours later, the ipsilateral temporal lobe was dissected for mRNA preparation. Six temporal lobe preparations from each group were analysed for differential gene expression. In control (non-kindled) rats, LEV treatment was devoid of any significant effect on gene expression. In saline-treated kindled rats, a large number of genes were observed to display mRNA expression alterations compared with non-kindled rats. LEV treatment induced marked effects on gene expression from kindled rats. Previously described epilepsy-related genes, such as neuropeptide Y (NPY), thyrotropin-releasing hormone (TRH) and glial fibrillary acidic protein (GFAP) were confirmed to be up-regulated by kindling and partially normalized by LEV treatment. Real-time quantitative polymerase chain reaction confirmed NPY, TRH and GFAP expression data from chip experiments. Furthermore, a number of novel genes were identified from the gene chip experiments. A subgroup of these genes demonstrated correlation between expression changes and kindled phenotype measurements. In summary, this study identified many genes with potentially important roles in epileptogenesis and highlighted several important issues in using the gene chip technology for the study of animal models of CNS disorders.
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PMID:The antiepileptic drug levetiracetam selectively modifies kindling-induced alterations in gene expression in the temporal lobe of rats. 1472 28

Electroconvulsive therapy (ECT) remains the treatment of choice for drug-resistant patients with depressive disorders, yet the mechanism for its efficacy remains unknown. Gene transcription changes were measured in the frontal cortex and hippocampus of rats subjected to sham seizures or to 1 or 10 electroconvulsive seizures (ECS), a model of ECT. Among the 3500-4400 RNA sequences detected in each sample, ECS increased by 1.5- to 11-fold or decreased by at least 34% the expression of 120 unique genes. The hippocampus produced more than three times the number of gene changes seen in the cortex, and many hippocampal gene changes persisted with chronic ECS, unlike in the cortex. Among the 120 genes, 77 have not been reported in previous studies of ECS or seizure responses, and 39 were confirmed among 59 studied by quantitative real time PCR. Another 19 genes, 10 previously unreported, changed by <1.5-fold but with very high significance. Multiple genes were identified within distinct pathways, including the BDNF-MAP kinase-cAMP-cAMP response element-binding protein pathway (15 genes), the arachidonic acid pathway (5 genes), and more than 10 genes in each of the immediate-early gene, neurogenesis, and exercise response gene groups. Neurogenesis, neurite outgrowth, and neuronal plasticity associated with BDNF, glutamate, and cAMP-protein kinase A signaling pathways may mediate the antidepressant effects of ECT in humans. These genes, and others that increase only with chronic ECS such as neuropeptide Y and thyrotropin-releasing hormone, may provide novel ways to select drugs for the treatment of depression and mimic the rapid effectiveness of ECT.
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PMID:Electroconvulsive seizures regulate gene expression of distinct neurotrophic signaling pathways. 1502 59

We describe a case of West syndrome with the balanced translocation t(X;18)(p22;p11.2). Treatment with high-dose vitamin B6, adrenocorticotropic hormone, thyrotropin-releasing hormone, and antiepileptic compounds was not effective, and the patient exhibited persistent refractory seizures and severe developmental delays. Although no mutation analysis and X chromosome inactivation were performed, we suggest that the chromosomal abnormality in the present patient is the main etiologic factor responsible for the infantile spasms and severe developmental delay.
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PMID:West syndrome in a patient with balanced translocation t(X;18)(p22;p11.2). 1762 26

Basic scientific advances in understanding the neuropsychobiology of bipolar disorder have given us a multitude of opportunities to explore and exploit new avenues of therapeutics. Pharmacotherapeutic approaches include: neuropeptides (agonists such as thyrotropin-releasing hormone and antagonists such as corticotropin-releasing hormone), neurotrophic factors (especially brain-derived neurotrophic factor), and glutamatergic mechanisms (such as riluzole, ketamine, and antagonists of the NR-2B subunit of the glutamate receptor). Physiological interventions that would offer alternatives to electroconvulsive therapy include: repeated transcranial magnetic stimulation, especially at more intense stimulation parameters; magnetic stimulation therapy (seizures induced more focally by magnetic rather than electrical stimulation with resulting reduced meaning loss); vagal nerve stimulation, and deep brain stimulation. However, these, as well as the panoply of existing treatments, require further intensive investigation to place each of them in the proper therapeutic sequence and combination for the individual patient, based on development of better clinical and biological predictors of response. Large clinical trial networks and development of systematic research in clinical practice settings, such as that featured by the National Cancer Institute for cancer chemotherapy, would greatly accelerate the progress in incorporating new, as well as existing, agents into the best treatment strategies. The bipolar disorders, which are increasingly recognized as complex, highly comorbid conditions with a high morbidity and mortality, of which the majority start in childhood and adolescence, are not likely to respond completely to any single new treatment agent, and new public health initiatives and research strategies are needed as much as any new single treatment advance.
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PMID:Promising avenues of therapeutics for bipolar illness. 1868 89

Both seizures and antiepileptic drugs may induce disturbances in hormonal system. Regarding endocrine effects of anticonvulsants, an interaction of these drugs with gonadal, thyroid, and adrenal axis deserves attention. Since majority of antiepileptic drugs block voltage dependent sodium and calcium channels, enhance GABAergic transmission and/or antagonize glutamate receptors, one may expect that similar neurochemical mechanisms are engaged in the interaction of these drugs with synthesis of hypothalamic neurohormones such as gonadotropin-releasing hormone (GnRH), thyrotropin-releasing hormone (TRH), corticotropin-releasing hormone (CRH) and growth hormone releasing hormone (GHRH). Moreover some antiepileptic drugs may affect hormone metabolism via inhibiting or stimulating cytochrome P-450 iso-enzymes. An influence of antiepileptic drugs on hypothalamic-pituitary-gonadal axis appears to be sex-dependent. In males, valproate decreased follicle-stimulating hormone (FSH) and luteinizing hormone (LH) but elevated dehydroepiandrosterone sulfate (DHEAS) concentrations. Carbamazepine decreased testosterone/sex-hormone binding globulin (SHBG) ratio, whereas its active metabolite--oxcarbazepine--had no effect on androgens. In females, valproate decreased FSH-stimulated estradiol release and enhanced testosterone level. On the other hand, carbamazepine decreased testosterone level but enhanced SHBG concentration. It has been reported that carbamazepine, oxcarbazepine or joined administration of carbamazepine and valproate decrease thyroxine (T4) level in patients with no effect on thyrotropin (TSH). While valproate itself has no effect on T4, phenytoin, phenobarbital and primidone, as metabolic enzyme inducers, can decrease the level of free and bound thyroxine. On the other hand, new antiepileptics such as levetiracetam, tiagabine, vigabatrine or lamotrigine had no effect on thyroid hormones. With respect to hormonal regulation of metabolic processes, valproate was reported to enhance leptin and insulin blood level and increased body weight, whereas topiramate showed an opposite effect. In contrast to thyroid and gonadal hormones, only a few data concern antiepileptic drug action in HPA axis. To this end, no effect of antiepileptic drugs on adrenocorticotropic hormone (ACTH)/cortisol circadian rhytmicity was found. Valproate decreased CRH release in rats, whereas lamotrigine stabilized ACTH/cortisol secretion. Moreover, felbamate was found to inhibit stress-induced corticosterone release in mice. Interestingly, recent data suggest that felbamat and some other new antiepileptic drugs may inhibit transcriptional activity of glucocorticoid receptors. Summing up, the above data suggest that traditional antiepileptic drugs may cause endocrine disturbances, especially in gonadal hormones.
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PMID:[Endocrine effects of antiepileptic drugs]. 1920 63

Infantile spasms are an epilepsy syndrome with distinctive features, including age onset during infancy, characteristic epileptic spasms, and specific electroencephalographic patterns (interictal hypsarrhythmia and ictal voltage suppression). Adrenocorticotropic hormone (ACTH) was first employed to treat infantile spasms in 1958, and since then it has been tried in prospective and retrospective studies for infantile spasms. Oral corticosteroids were also used in a few studies for infantile spasms. Variable success in cessation of infantile spasms and normalization of electroencephalograms was demonstrated. However, frequent significant adverse effects are associated with ACTH and oral corticosteroids. Vigabatrin has been used since the 1990s, and shown to be successful in resolution of infantile spasms, especially for infantile spasms associated with tuberous sclerosis. It is associated with visual field constriction, which is often asymptomatic and requires perimetric visual field study to identify. When ACTH, oral corticosteroids, and vigabatrin fail to induce cessation of infantile spasms, other alternative treatments include valproic acid, nitrazepam, pyridoxine, topiramate, zonisamide, lamotrigine, levetiracetam, felbamate, ganaxolone, liposteroid, thyrotropin-releasing hormone, intravenous immunoglobulin and a ketogenic diet. Rarely, infantile spasms in association with biotinidase deficiency, phenylketonuria, and pyridoxine-dependent seizures are successfully treated with biotin, a low phenylalanine diet, and pyridoxine, respectively. For medically intractable infantile spasms, some properly selected patients may have complete cessation of infantile spasms with appropriate surgical treatments.
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PMID:Current trends in the treatment of infantile spasms. 1955 23

In the present study, L-pGlu-(1-benzyl)-L-His-L-ProNH(2) (NP-355), a newer CNS active thyrotropin-releasing hormone (TRH) analog was evaluated for its antiepileptic potential. NP-355 (5, 10 and 20 micromol/kg; i.v.) pretreatment significantly delayed onset and reduced the frequency of convulsions in pentylenetetrazole-induced seizures. NP-355 was also found to be protective against picrotoxin- and kainic acid-induced seizures. Maximum electroshock-induced seizures were not protected even at 20 micromol/kg in mice. Effects of NP-355 on functional observation battery did not exhibit any undesirable effects. Moreover, the antiepileptic activity produced by NP-355 was observed without significantly altering mean arterial blood pressure. NP-355 significantly increases the CBF to 17+/-3% as compared to saline (6+/-2%). NP-355 (100, 300 and 1000 microM) produces a concentration-dependent depression (16%, 63% and 77%, respectively) of the peak sodium current. NP-355 did not alter neurobehavioral parameters. This study demonstrates that NP-355 has potential antiepileptic activity and devoid of undesirable effects.
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PMID:Neuropharmacological profile of L-pGlu-(1-benzyl)-L-His-L-ProNH2, a newer thyrotropin-releasing hormone analog: effects on seizure models, sodium current, cerebral blood flow and behavioral parameters. 1983 80


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