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)

Genetic variation in G protein-coupled receptors (GPCRs) results in the disruption of GPCR function in a wide variety of human genetic diseases. In vitro strategies have been used to elucidate the molecular pathologies that underlie naturally occurring GPCR mutations. Various degrees of inactive, overactive, or constitutively active receptors have been identified. These mutations often alter ligand binding, G protein coupling, receptor desensitization, and receptor recycling. The role of inactivating and activating calcium-sensing receptor (CASR) mutations is discussed with respect to familial hypocalciuric hypercalemia (FHH) and autosomal dominant hypocalemia (ADH). Among ADH mutations, those associated with tonic-clonic seizures are discussed. Other receptors discussed include rhodopsin, thyrotropin, parathyroid hormone, melanocortin, follicle-stimulating hormone, luteinizing hormone, gonadotropin-releasing hormone (GnRHR), adrenocorticotropic hormone, vasopressin, endothelin-beta, purinergic, and the G protein associated with asthma (GPRA). Diseases caused by mutations that disrupt GPCR function are significant because they might be selectively targeted by drugs that rescue altered receptors. Examples of drug development based on targeting GPCRs mutated in disease include the calcimimetics used to compensate for some CASR mutations, obesity therapeutics targeting melanocortin receptors, interventions that alter GnRHR loss from the cell surface in idiopathic hypogonadotropic hypogonadism and novel drugs that might rescue the P2RY12 receptor in a rare bleeding disorder. The discovery of GPRA suggests that drug screens against variant GPCRs may identify novel drugs. This review of the variety of GPCRs that are disrupted in monogenic disease provides the basis for examining the significance of common pharmacogenetic variants.
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PMID:G protein-coupled receptors disrupted in human genetic disease. 1837 Feb 33

Alcohol Denat. is the generic term used by the cosmetics industry to describe denatured alcohol. Alcohol Denat. and various specially denatured (SD) alcohols are used as cosmetic ingredients in a wide variety of products. Many denaturants have been previously considered, on an individual basis, as cosmetic ingredients by the Cosmetic Ingredient Review (CIR) Expert Panel, whereas others, including Brucine and Brucine Sulfate, Denatonium Benzoate, and Quassin, have not previously been evaluated. Quassin is a bitter alkaloid obtained from the wood of Quassia amara. Quassin has been used as an insect antifeedant and insecticide and several studies demonstrate its effectiveness. At oral doses up to 1000 mg/kg using rats, Quassin was not toxic in acute and short-term tests, but some reversible piloerection, decrease in motor activity, and a partial loss of righting reflex were found in mice at 500 mg/kg. At 1000 mg/kg given intraperitoneally (i.p.), all mice died within 24 h of receiving treatment. In a cytotoxicity test with brine shrimp, 1 mg/ml of Quassin did not possess any cytotoxic or antiplasmodial activity. Quassin administered to rat Leydig cells in vitro at concentrations of 5-25 ng/ml inhibited both the basal and luteinizing hormone (LH)-stimulated testosterone secretion in a dose-related fashion. Quassin at doses up to 2.0 g/kg in drinking water using rats produced no significant effect on the body weights, but the mean weights of the testes, seminal vesicles, and epididymides were significantly reduced, and the weights of the anterior pituitary glands were significantly increased. The sperm counts and levels of LH, follicle-stimulating hormone (FSH), and testosterone were significantly lower in groups treated with Quassin. Brucine is a derivative of 2-hydroxystrychnine. Swiss-Webster mice given Brucine base, 30 ml/kg, had an acute oral LD(50) of 150 mg/kg, with central nervous system depression followed by convulsions and seizures in some cases. In those animals that died, respiratory arrest was the cause. The acute i.p. LD(50) for 15 ml/kg of Brucine base was 62.0 mg/kg, with central nervous system depression prior to the onset of convulsions, just as with oral Brucine. The acute intravenous (i.v.) LD(50) was 12.0 mg/kg. Brucine was nonmutagenic in an Ames assay at levels up to 6666 mu g/plate, with and without metabolic activation. In a repeat-insult patch test, for a hair care product containing 47% SD Alcohol 40 (95%), it was reported that Brucine Sulfate may be considered a nonprimary irritant and a nonprimary sensitizer. Three different sunscreen products (35% SD Alcohol 40-B, 72.4% SD Alcohol 40, and 74.5% SD Alcohol 40) did not show any signs of photoallergy in human subjects. Also, these three formulas did not exhibit any evidence of phototoxicity in humans. Denatonium Benzoate is a bitter substance detectable at a concentration of 10 ppb, discernibly bitter at 50 ppb, and unpleasantly bitter at 10 ppm. The distribution of topically applied lidocaine, a topical anesthetic chemically related to Denatonium Benzoate demonstrated that virtually no lidocaine appears in the plasma, suggesting that the larger Denatonium Benzoate molecule also would have little or no systemic exposure. Denatonium Benzoate (0.1%) did not show adverse effects in 10 rats in an acute inhalation toxicity test and 0.005% to 0.05% was nonirritating to ocular mucosa in 6 albino rabbits. The acute oral LD(50) for the male rats was 640 mg/kg and for females, 584 mg/kg. The LD(50) for the male rabbits was 508 mg/kg and for the female rabbits, 640 mg/kg. In two chronic toxicity studies, Denatonium Benzoate was administered (by gavage) at 1.6, 8, and 16 mg/kg/day, one using cynomologus monkeys and the other rats, resulted in no compound-related toxicity. The toxicity of SD Alcohols has also been tested, with implications for the particular denaturant used. An irritation test of 55.65% SD Alcohol 40-B denatured with Denatonium Benzoate using rabbits produced minimal effects. A spray formula containing 12% SD Alcohol 40-B was found to be nonirritating when evaluated for vaginal mucosal irritation in New Zealand white rabbits. Cosmetic formulations containing SD Alcohol 40-B (denatured with Denatonium Benzoate) were not sensitizers in repeated insult patch tests. A gel formula containing 29% SD Alcohol 40-B and a spray liquid containing 12% SD Alcohol 40-B did not induce photoallergy, dermal sensitization, or phototoxic response in human subjects. Although the absorption of ethanol (aka Alcohol for purposes of cosmetic ingredient labeling) occurs through skin, ethanol does not appear to affect the integrity of the skin barrier nor reach a very high systemic concentration following dermal exposure. Ethanol may be found in the bloodstream as a result of inhalation exposure and ingestion. Topically applied, ethanol can act as a penetration enhancer. Most of the systemic toxicity of ethanol appears to be associated with chronic abuse of alcohol. Although ethanol is denatured to make it unfit for consumption, there have been reports of intentional and unintentional consumption of products containing denatured alcohol. Ethanol is a reproductive and developmental toxicant. Ethanol is genotoxic in some test systems and it has been proposed that the genotoxic effects of ethanol are mediated via its metabolite, acetaldehyde. A brief summary is provided of the effects of chronic ingestion of alcohol including intoxication, liver damage, brain damage, and possible carcinogenicity. The CIR Expert Panel recognizes that certain ingredients in this group are reportedly used in a given product category, but the concentration of use is not available. Because dermal application or inhalation of cosmetic products containing these ingredients will not produce significant systemic exposure to ethanol, the CIR Expert Panel concluded that safety of the ingredients should be predicated on the safety of the denaturants used. The Panel considered that the adverse effects known to be associated with Alcohol ingestion included in this safety assessment do not suggest a concern for Alcohol Denat. or SD Alcohols because of the presence of the denaturants, which are added for the express purpose of making the Alcohol unpotable. The CIR Expert Panel has previously conducted safety assessments of t-Butyl Alcohol, Diethyl Phthalate, Methyl Alcohol, Salicylic Acid, Sodium Salicylate, and Methyl Salicylate, in which each was affirmed safe or safe with qualifications. Given their use as denaturants are at low concentrations of use in Alcohol, the CIR Expert Panel determined that Alcohol Denat. denatured with t-Butyl Alcohol, Diethyl Phthalate, Methyl Alcohol, Salicylic Acid, Sodium Salicylate, and Methyl Salicylate is safe as used in cosmetic formulations with no qualifications. Likewise, because they are denatured with either t-Butyl Alcohol, Diethyl Phthalate, or Methyl Alcohol, SD Alcohols 3-A, 30, 39-B, 39-C, and 40-C all are considered safe as used. The Panel considered the available data for Denatonium Benzoate and SD Alcohol 40-B to be sufficient to support the safety of these ingredients in cosmetics. Denatonium Benzoate is sufficiently bitter that it is an effective denaturant at only 0.0006%. The Panel recognized that data on dermal penetration of Denatonium Benzoate were not available, but considered that the available data on lidocaine, a smaller structurally related chemical, indicates that dermal exposure does not result in measurable systemic exposure. The available data, however, were not sufficient to support the safety of Quassin, Brucine, and Brucine Sulfate, Alcohol Denat. denatured with those denaturants, or SD Alcohol 39 and SD Alcohol 40 (SD Alcohols denatured with Quassin, Brucine, and/or Brucine Sulfate), and in order for the Expert Panel to reach a conclusion for these denaturants, additional data are needed.
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PMID:Final report of the safety assessment of Alcohol Denat., including SD Alcohol 3-A, SD Alcohol 30, SD Alcohol 39, SD Alcohol 39-B, SD Alcohol 39-C, SD Alcohol 40, SD Alcohol 40-B, and SD Alcohol 40-C, and the denaturants, Quassin, Brucine Sulfate/Brucine, and Denatonium Benzoate. 1856 60

The lde/lde rats show a severe dwarf phenotype with early postnatal lethality and a high incidence of epileptic seizure. Seizures are first detected in this model between 16 and 63 days of age, and mostly begin as wild running and progress to generalized tonic-clonic convulsions. Because our histological examination detected many extracellular vacuoles in the hippocampus and amygdaloid bodies of these animals at 28 days of age, these pathological alterations may be related to the epileptogenesis in lde/lde rats. In addition to these defects, male lde/lde rats have apparently smaller testes with reduced number of germ cells and poorly matured adult-type Leydig cells in comparison with wild-type controls. In the present study, we performed anatomical, histological, and endocrinologic examinations to characterize the testicular phenotype of lde/lde rats at 21, 28, 35, and 56 days of age. Male lde/lde rats showed severely retarded growth of the testes and accessory sex organs. Their seminiferous tubules were significantly smaller and contained markedly fewer germ cells at all time points examined as compared with controls. Significantly fewer Sertoli cells at 21 and 28 days of age, markedly decreased spermatocyte number at 28 days of age, and delayed appearance of spermatids at 56 days of age were observed in the testes of lde/lde rats. More TUNEL (T&T-mediated duTP-biotin nick-end labeling)-positive cells were detected in lde/lde seminiferous tubules, and the largest number of apoptotic cells was recorded at 28 days of age. The increases in 3beta-hydroxysteroid dehydrogenase-positive adult-type Leydig cells and 11beta-hydroxysteroid dehydrogenase-positive mature adult-type Leydig cells were also severely retarded in the testes of lde/lde rats. Consistent with these defects, significantly lower plasma follicle-stimulating hormone (FSH), luteinizing hormone (LH), and testosterone concentrations were detected in lde/lde males at 28 days of age, and weak immunostaining for FSH and smaller cytoplasm of LH-positive cells were detected in the anterior pituitary lobes of lde/lde males. Despite a normal level of plasma LH after 35 days of age, a significantly lower level of plasma testosterone was detected at 56 days of age. These results indicate that the normal lde allele is related to prepubertal elevations of gonadotropins and normal development of adult-type Leydig cells. Because lde/lde rats experience epileptic seizures during the period when the hypothalamus-pituitary-testicular axis is established, lde/lde rats would be useful as a model for reproductive disorder with pediatric epilepsy.
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PMID:Retarded differentiation of Leydig cells and increased apoptosis of germ cells in the initial round of spermatogenesis of rats with lethal dwarf and epilepsy (lde/lde) phenotypes. 1867 60

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

Pyridoxal phosphate and pyridoxamine phosphate, the catalytically active forms of vitamin B(6), influence brain function by participating at stages in metabolism of proteins, lipids, carbohydrates, other coenzymes and hormones. Vitamin B(6) participates in the metabolism of amino acids in the form of decarboxylation, transamination, deamination, racemization and desulfhydration reactions. The crucial roles that these coenzymes play in the maintenance of functional integrity of the brain become evident when one realizes that some compounds implicated as neurotransmitters are synthesized and/or metabolized by the aid of the vitamin B(6)-dependent enzymatic reactions. These include dopamine, norepinephrine and serotonin, tyramine, tryptamine, taurine, histamine, gamma aminobutyric acid, and even acetylcholine indirectly. In recent years, the above-mentioned biogenic amines have become of considerable interest to neurobiologists who are investigating the etiology and the pathological manifestations of many disorders of the central nervous system such as Parkinsonism, Huntington's chorea, minimal brain disfunction, schizophrenia, depression, sleep disorders and seizure disorders. Vitamin B(6) deficiency in these cases is characterized by anemia, growth retardation and alteration in neuronal function, including neuropathies, hyperirritability, hyperexcitability and convulsions. The importance of vitamin B(6) in the study of brain function assumes still greater significance when one considers the effects of nutritional deficiencies on growth and development of the brain and mental processes and in the involvement of vitamin B(6) in some inborn errors of metabolism which result in mental retardation. Vitamin B(6) deficiency results in a lowered concentration of Coenzyme A in blood, in reduced absorption and storage of vitamin B(12), and in increased excretion of vitamin C. Furthermore, vitamin B(6) acts synergistically with vitamin E to control metabolism of unsaturated fats, with vitamin C in tyrosine metabolism and with niacin in its action and participates in niacin synthesis. In addition, vitamin B(6) deficiency results in insufficiency of insulin and in alteration of the functions of adrenal and pituitary glands, since it is involved in the synthesis of growth hormone, follicle-stimulating hormone, luteinizing hormone, aldosterone, glucagon, cortisol, estradiol, testosterone and epinephrine. It is hoped that by understanding the factors that regulate the synthesis, binding, storage and degradation of pyridoxal phosphate in the brain, a better insight into the role of vitamin B(6) in neurobiology may be gained.
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PMID:Regulation and function of pyridoxal phosphate in CNS. 1964 63

Postictal increases in prolactin (PRL), luteinizing hormone, and follicle-stimulating hormone have been recorded in patients with both generalized tonic-clonic and partial seizures. Elevations of PRL and luteinizing hormone were seen immediately and at 20 minutes after generalized tonic-clonic seizures in male and female patients. Usually, PRL blood levels return to normal values within 1 hour. Previous studies have evaluated the utility of the transient increases in PRL, neuron-specific enolase, and S-100 protein as markers of epileptic seizures in children and adults. The conclusion was that measurement of serum PRL is a reliable confirmatory test in the presence of a seizure, but only modestly effective as a screening test for suspected seizures. Temporal lobe epilepsy is associated with abnormalities of reproductive physiology, but the mechanisms of hormonal dysregulation are not clear. A direct influence of epilepsy on the reproductive endocrine system is suggested by acute changes in PRL and gonadotropin levels following generalized and partial seizures, pointing to a possible relationship between temporolimbic epileptiform discharges and particular reproductive endocrine disorders. Chronic effects of the epileptic state and the acute impact of seizures could alter hypothalamic function, as indicated by downstream pulsatile secretion of luteinizing hormone. The brain controls reproductive function primarily through hypothalamic regulation of pituitary secretion regions of the hypothalamus. These are areas that are involved in the regulation, production, and secretion of gonadotropin-releasing hormone and receive extensive direct connections from the cerebral hemispheres, especially from temporolimbic structures, most notably from the amygdala, that are commonly involved in temporal lobe epilepsy. Significant relationships have been uncovered through which ictal and postictal effects of seizures and epilepsy may influence the function of this complex neuroendocrine system.
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PMID:Hormonal alterations following seizures. 2069 21

Hypothalamic hamartomas (HHs) are benign lesions that are often associated with central precocious puberty and may present with gelastic seizures. Treatment modalities for HH include medical therapy with long-term gonadotropin-releasing hormone analogs or resection. The authors report the case of a 7-year-old girl who was diagnosed with an HH due to precocious puberty and was treated medically with a gonadotropin-releasing hormone analog for 3 years. Despite normalization of her plasma levels of luteinizing hormone, follicle-stimulating hormone, and estradiol and arrest of her precocious puberty, the patient developed progressive weight gain associated with extreme hyperphagia and morbid obesity by the age of 10 years. Her compulsive eating patterns were refractory to counseling and other interventions attempted by her parents and physicians. After resection of the HH, her hyperphagia resolved and her weight stabilized. To the authors' knowledge, this is the first report describing resection of an HH for the purpose of treating hyperphagia and obesity.
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PMID:Successful treatment of hyperphagia by resection of a hypothalamic hamartoma. 2357 Apr 42

Klinefelter syndrome is a disorder of variation of sex chromosome, the most common karyotype being 47XXY. Multiple case reports and articles have been published linking the increased prevalence of psychiatric disorders like Schizophrenia, Schizophreniform psychosis, Attention deficit hyperkinetic disorder, Learning disorder, etc. and seizure disorder in Klinefelter syndrome than in general population, attributing to the extra X chromosome. Here is a case of a 45-year-old gentleman with Klinefelter syndrome with schizophrenia-like psychosis and seizure disorder. He was diagnosed as Klinefelter syndrome 15 years back by genetic testing (47XXY) when he was investigated for infertility. His luteinizing hormone (LH) (32.04 mIU/ml) and follicle-stimulating hormone (FSH) (50.70 mIU/ml) levels were high and his testosterone level was low (1.76 ng/ml). He had four episodes of seizures in 2004 for which he was started on phenytoin and sodium valproate, and was seizure-free for past 10 years. He was brought to our hospital in July 2014 with complaints of talking and laughing to self, suspicion, hearing voices and aggressive behaviour, which were persistent mildly for past 15 years and aggravated for past 6 months. He was not going for work for past 15 years, does not mingle with relatives or friends.
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PMID:A Case Report of Klinefelter Syndrome with Schizophrenia-Like Psychosis and Seizure Disorder. 2666 93


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