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

In an effort to detect active renal tubular dysfunction in 74 epileptic patients being treated with antiepileptic drugs (AEDs), we measured the urinary activity of two lysosomal enzymes, N-acetyl-beta-glucosaminidase (NAG) and beta-galactosidase (beta-gal). The heterogeneity of the types of seizures and therapeutic regimens permitted us to examine the potential differences in AED effects. We also examined the chronological changes in the urinary excretion rates of NAG and beta-gal in 132 healthy controls, aged 3 months to 37 years. Increased NAG excretion rates (defined as > or = 2 S.D. compared with age-matched controls) were found in 36.5% of the patients. Valproic acid was highly associated with this increase, and in combination with potassium bromide caused the highest levels of NAG excretion. Among the patients taking carbamazepine, only 11.1% exhibited high levels of NAG in urine. Children under 1 year of age showed higher levels of NAG excretion than older patients. In spite of the abnormally high urinary excretion of NAG, we could not detect any signs of renal dysfunction by urinalysis and measurement of blood urea nitrogen and serum electrolytes. We cannot exclude the possibility that the increased levels of urinary NAG in epileptic patients might be due to renal tubular enzyme induction by AEDs.
 ...
PMID:Urinary excretion of N-acetyl-beta-glucosaminidase and beta-galactosidase by patients with epilepsy. 821 37

To evaluate the potential for lipofectin-mediated central nervous system gene transfer, the plasmid coding for cholecystokinin was administered intracerebroventricularly to rats, which have congenital audiogenic seizures and high responses to peripheral electric stimulation-induced analgesia. Previous studies had shown that low brain cholecystokinin levels may be the neurochemical variable of rat's audiogenic seizure and high responses to the analgesia because cholecystokinin is an anticonvulsant and anti-opioid neuropeptide. Gene transfer of cholecystokinin corrected the increased susceptibility to audiogenic seizures and the high responses to analgesia for about one week. Similar administration of plasmid expressing beta-galactosidase indicated that the vector mainly transfected ependymal cells lining the ventricle and pia mater cells. The increased cholecystokinin messenger RNA and immunoreactivity in the hippocampus following stereotactic intrahippocampal administration of cholecystokinin plasmid was also demonstrated with in situ hybridization and immunohistochemistry techniques. These results suggest that lipofectin-mediated gene transfer will be useful for studies of brain function, the modification of behavior and gene therapy for central nervous system disorders.
 ...
PMID:Lipofectin-facilitated transfer of cholecystokinin gene corrects behavioral abnormalities of rats with audiogenic seizures. 904 70

As a first step in the development of a gene therapy approach to epilepsy, we evaluated the ability of adenovirus vectors to direct the transfer into and expression of a marker gene in human brain slices obtained from patients undergoing surgery for medically intractable epilepsy. Following injection of adenovirus vectors containing the Escherichia coli lacZ gene into hippocampal and cortical brain slices, lacZ mRNA, beta-galactosidase protein, and enzymatic activity were detected, confirming successful gene transfer, transcription, and translation into a functional protein. Transfected cells were predominantly glial, with some neurons expressing beta-galactosidase as well. These results support the potential of adenovirus vectors to transfer genetic information into human epileptogenic brain, resulting in expression of the gene into a functional protein. These findings also have implications for the development of gene therapy approaches to certain seizure disorders. A number of potential therapeutic approaches are discussed, including the elevation of inhibitory neurotransmitter or neuropeptide levels, expression or modulation of postsynaptic receptors, and manipulation of signal transduction systems.
 ...
PMID:Adenovirus vector-mediated gene transfer into human epileptogenic brain slices: prospects for gene therapy in epilepsy. 939 59

An impairment of GABA(A)-receptor-mediated inhibitory neurotransmission has been implicated in the development of epileptic seizures. To determine whether seizures affect GABA(A)-receptor gene transcription in vivo, a transgenic mouse line carrying a lacZ-fusion gene driven by GABA(A)-receptor delta-subunit promoter and upstream sequences was subjected to pentylenetetrazol (PTZ)-induced seizures. After injection of a single convulsive dose of PTZ, the activity of the delta-subunit promoter, as monitored by beta-galactosidase immunohistochemistry, was increased selectively in neurons of layers II-IV of neocortex. In contrast, mice kindled by repeated administration of initially subconvulsive doses of PTZ did not show a change in transgene expression, even shortly after the last PTZ-induced seizure. These results show that transient changes in transcription of the GABA(A)-receptor delta-subunit gene occur after acute seizures, but not after kindling. The limited responsiveness of the GABA(A)-receptor delta-subunit promoter after repeated stimulation may reflect an inappropriate adaptation of cellular responses to recurrent excitation, thereby contributing to the development of seizure disorders.
 ...
PMID:Activation of the GABA(A)-receptor delta-subunit gene promoter following pentylenetetrazole-induced seizures in transgenic mice. 942 23

We describe 3-year clinical course of a 54-year-old Japanese man who presented with action myoclonus, parkinsonism and epilepsy. There was no family history or consanguinity. The patient was well until the age of 51 years (in 1986), when he noted slow movements, memory disturbance and left hand tremor. He was treated with anti-Parkinson drugs without any improvements. Soon thereafter, he developed a gait disturbance and generalized tonic clonic seizures. He was admitted to our service at the age of 53 years. General physical examination revealed no hepatosplenomegaly. Neurological examination showed mild dementia. Neither retinal pigmentation nor cherry red spot was noted. He was unable to walk due to marked frozen gait. His upward gaze was limited and saccadic eye movement was slow. He had action myoclonus in both upper extremities and resting tremor on the left side. He showed mild left hemiparesis. Deep tendon reflex was hyperactive in both side with extensor plantar responses. MRI demonstrated cortical atrophy, especially marked at the bilateral temporal lobes with a right side predominance. Leukocyte lysosomal enzyme activities of beta-hexosaminidase, beta-galactosidase and sialidase were within normal limits. The patient died of pneumonia on April 25, 1989. At the time of a neurological CPC, neurologists reached the clinical diagnosis of adult-type neuronal ceroid-lipofuscinosis. Postmortem examination revealed bilateral bronchopneumonia. The brain weighed 1,219 g and showed atrophy of the temporal lobes. Histological examination showed neuronal cells with swollen cytoplasm and lipofuscin-like granules throughout the CNS, including the cerebral cortex, thalamus, substantia nigra, motor nuclei of the brain stem, dentate nuclei, inferior olivary nuclei. Clarke's nuclei and anterior horn cells. Marked neuronal loss was noted in the right temporal lobe and substantia nigra. Electron micrographs of the frontal cortex revealed "fingerprint profiles" in the cytoplasm of neuronal and glial cells. Pathological findings were consistent with the diagnosis of adult-type neuronal ceroid-lipofuscinosis (Kufs' disease).
 ...
PMID:[A 54-year-old man with action myoclonus, parkinsonism and epilepsy]. 1058 20

Transplantation of genetically engineered cells can provide sustained focal delivery of naturally occurring molecules, including neurotransmitters and growth factors. We have engineered immortalized mouse cortical neurons and glia to deliver GABA by driving GAD(65) expression. Engineered cell lines showed GAD(65) mRNA expression, enzymatic activity, and GABA release. In vitro, basal flux of GABA was approximately 20% of total cellular GABA. We transplanted these GABA-producing cells bilaterally into either the anterior or the posterior substantia nigra of 43 rats. The rats were subsequently kindled through an electrode placed in the entorhinal cortex. GABA-producing cells, but not beta-galactosidase-producing cells, affected kindling rates. The number of stimulations needed to reach the first stage-5 seizure and to achieve full kindling differed significantly between the anterior and posterior transplantation sites when GAD(65)-producing cells were transplanted but not when beta-galactosidase-producing cells were transplanted. Our data show that transplanted engineered cells can make and release GABA at physiologically meaningful concentrations.
 ...
PMID:Conditionally immortalized cell lines, engineered to produce and release GABA, modulate the development of behavioral seizures. 1068 70

We have cross-bred twitcher mice (galactosylceramidase deficiency) and acid beta-galactosidase knockout mice (G(M1) gangliosidosis) and found that the acid beta-galactosidase gene dosage exerts an unexpected and paradoxical influence on the twitcher phenotype. Twitcher mice with an additional complete deficiency of acid beta-galactosidase have the mildest phenotype with the longest lifespan and nearly rescued CNS pathology. In contrast, twitcher mice with a single functional acid beta-galactosidase gene have the most severe disease with the shortest lifespan, despite the fact that G(M1) gangliosidosis carrier mice with an otherwise normal genetic background are phenotypically normal. A significant proportion of these galc(-/-), bgal(+/-) mice clinically develop additional extreme hyper-reactivity and generalized seizures not seen in any other genotypes. Consistent with the clinical seizures, widespread neuronal degeneration is present in the galc(-/-), bgal(+/-) mice, most prominently in the CA3 region of the hippocampus. The double knockout mice show a massive accumulation of lactosylceramide in all tissues. The brain inexplicably contains only a half-normal amount of galactosylceramide, which may account for the mild clinical and pathological phenotype. On the other hand, brain psychosine level is increased in all twitcher mice, but galc(-/-), bgal(+/-) mice show a significantly higher level than other genotypes. The reduced galactosylceramide in the brain of the double knockout mice and the significantly higher psychosine in the brain of the galc(-/-), bgal(+/-) mice cannot readily be explained from the genotypes of these mice. These observations are contrary to the expected outcome of Mendelian autosomal recessive single gene disorders and may also be interpreted as that the acid beta-galactosidase gene functions as a modifier gene for the phenotypic expression of genetic galactosylceramidase deficiency.
 ...
PMID:Paradoxical influence of acid beta-galactosidase gene dosage on phenotype of the twitcher mouse (genetic galactosylceramidase deficiency). 1086 Dec 97

We hypothesized that overexpression of specific glutamate receptors within the hippocampus would induce seizures and the associated cellular changes seen in temporal lobe epilepsy (TLE). The GluR6 kainate receptor was overexpressed by injecting rat hippocampi with HSVGluR6, a viral vector transducing fully edited GluR6. These animals experienced limbic seizures approximately 4 h following the injection. Control animals injected with HSVlac, a vector expressing beta-galactosidase, did not have seizures. Recordings from hippocampal CA1 pyramidal cells were performed 12 to 48 h and 1 week to 1 month postinjection. We observed nonsynaptic Na(+)-mediated bursting in 77.5% of cells 12 to 48 h following injection of HSVGluR6 but not HSVlac. The synaptic responses were normal in both groups. However, the physiological properties of cells from HSVGluR6-injected hippocampi changed over time. Two weeks following HSVGluR6 injection, synaptic bursts could be evoked, but intrinsic bursting became rare. These changes persisted for at least 1 month. We postulate that this transition from intrinsic to synaptic hyperexcitability may be important in the development of TLE.
 ...
PMID:Overexpression of GluR6 in rat hippocampus produces seizures and spontaneous nonsynaptic bursting in vitro. 1096 7

Gene therapy is being investigated as a putative treatment option for cardiovascular diseases, including cerebral vasospasm. Because there is presently no information regarding gene transfer to human cerebral arteries, the principal objective of this study was to characterize adenovirus-mediated expression and function of recombinant endothelial nitric oxide synthase (eNOS) gene in human pial arteries. Pial arteries (outer diameter 500 to 1,000 microm) were isolated from 30 patients undergoing temporal lobectomy for intractable seizures and were studied using histologic staining, histochemistry, electron microscopy, and isometric force recording. Gene transfer experiments were performed ex vivo using adenoviral vectors encoding genes for bovine eNOS (AdCMVeNOS) and Escherichia coli beta-galactosidase (AdCMVLacZ). In transduced arteries, studied 24 hours after exposure to vectors, expression of recombinant beta-galactosidase and eNOS was detected by histochemistry, localizing mainly to the adventitia (n = 4). Immunoelectron microscopy localized recombinant eNOS in adventitial fibroblasts. During contractions to U46619, bradykinin-induced relaxations were significantly augmented in AdCMVeNOS-transduced rings compared with control and AdCMVLacZ-transduced rings (P < 0.01; n = 6). The NOS inhibitor L-nitroarginine methylester (L-NAME) caused significantly greater contraction in AdCMVeNOS-transduced rings (P < 0.001; n = 4) and inhibited bradykinin-induced relaxations in control and transduced rings (P < 0.001; n = 6). The current findings suggest that in AdCMVeNOS-transduced human pial arteries, expression of recombinant eNOS occurs mainly in adventitial fibroblasts where it augments relaxations to NO-dependent agonists such as bradykinin. Findings from the current study might be beneficial in future clinical applications of gene therapy for the treatment or prevention of cerebral vasospasm.
 ...
PMID:Adenovirus-mediated gene transfer to human cerebral arteries. 1099 58

Angelman syndrome (AS), characterized by motor dysfunction, mental retardation, and seizures, is caused by several genetic etiologies involving chromosome 15q11-q13, including mutations of the UBE3A gene. UBE3A encodes UBE3A/E6-AP, a ubiquitin-protein ligase, and shows brain-specific imprinting, with brain expression predominantly from the maternal allele. Lack of a functional maternal allele of UBE3A causes AS. In order to understand the causal relationship between maternal UBE3A mutations and AS, we have constructed a mouse model with targeted inactivation of Ube3a. The inactive allele contains a lacZ reporter gene for analysis of brain-specific imprinting. Maternal, but not paternal, transmission of the targeted allele leads to beta-galactosidase activity in hippocampal and cerebellar neurons. Maternal inheritance of the Ube3a mutant allele also causes impaired performance in tests of motor function and spatial learning, as well as abnormal hippocampal EEG recordings. As predicted from the dependence of UBE3A-mediated ubiquitination of p53 on HPV E6 protein, our maternal-deficient mice show normal brain p53 levels.
 ...
PMID:Neurobehavioral and electroencephalographic abnormalities in Ube3a maternal-deficient mice. 1189 68


<< Previous 1 2 3 Next >>