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Polychlorinated biphenyls (PCBs) cause a wide spectrum of toxic effects in the brain through undefined mechanisms. Exposure to the PCB mixture Aroclor-1254 (A1254) increases the repressor element-1 silencing transcription factor (REST) expression, leading to neuronal death. This study sought to understand the sequence of some molecular mechanisms to determine whether A1254 could increase REST expression and the cytoprotective effect of the phorbol ester tetradecanoylphorbol acetate (TPA) on A1254-induced toxicity in SH-SY5Y cells. As shown by Western blot analysis, A1254 (10 µg/ml) downregulates extracellular signal-related kinase 2 (ERK2) phosphorylation in a time-dependent manner, thereby triggering the binding of specificity protein 1 (Sp1) and Sp3 to the REST gene promoter as revealed by chromatin immunoprecipitation analysis. This chain of events results in an increase in REST mRNA and cell death, as assessed by quantitative real-time polymerase chain reaction and dimethylthiazolyl-2-5-diphenyltetrazolium-bromide assay, respectively. Accordingly, TPA prevented both the A1254-induced decrease in ERK2 phosphorylation and the A1254-induced increase in Sp1, Sp3, and REST protein expression. After 48 hr, TPA prevented A1254-induced cell death. ERK2 overexpression counteracted the A1254-induced increase in Sp1 and Sp3 protein expression and prevented A1254-induced Sp1 and Sp3 binding to the REST gene promoter, thus counteracting the increase in REST mRNA expression induced by the toxicant. In neuroblastoma SH-SY5Y cells, ERK2/Sp1/SP3/REST is a new pathway underlying the neurotoxic effect of PCB. The ERK2/Sp1/Sp3/REST pathway, which underlies A1254-induced neuronal death, might represent a new drug signaling cascade in PCB-induced neuronal toxicity

The Na(+)/Ca(2+) exchanger (NCX) is a plasma membrane protein that can switch Na(+) and Ca(2+) in either direction to maintain the homeostasis of intracellular Ca(2+). A family of three genes (NCX1, NCX2, and NCX3) has been identified in neurons and muscle cells. NCX activity has also been reported in certain immune cells (e.g., mast cells). We have examined the expression and function of these NCX isoforms in the human monocytes and lung macrophages. Monocytes were purified from peripheral blood of healthy donors. Macrophages (HLM) were isolated and purified from the lung parenchyma of patients undergoing thoracic surgery. NCX1 and NCX3, but not NCX2, were expressed in HLM and monocytes at both mRNA and protein level. Exposure to Na(+)-free medium induced a significant increase in intracellular calcium concentration ([Ca(2+)](i)) in both cell types, suggesting that NCX isoforms expressed on these cells were functionally active. This response was completely abolished by the NCX inhibitor 5-(N-4-chlorobenzyl)-20,40-dimethylbenzamil (CB-DMB). In addition, incubation of macrophages with Na(+)-free medium induced a marked release of TNF-??. Preincubation of HLM with CB-DMB and RNAi-mediated knockdown of NCX1 blocked TNF-?? release. Our results demonstrate that human macrophages and monocytes express NCX1 and NCX3 that operate in a bidirectional manner to restore [Ca(2+)](i) to generate Ca(2+) signals and to induce TNF-?? production. We suggest that NCX may modulate Ca(2+) homeostasis and proinflammatory functions in human macrophages and monocytes.

In celiac disease (CD), gluten, the disease-inducing toxic component in wheat, induces the secretion of IgA-class autoantibodies which target tissue transglutaminase (tTG). These autoantibodies are produced in the small-intestinal mucosa, and, during gluten consumption, they can also be detected in patients' serum but disappear slowly from the circulation on a gluten-free diet. Interestingly, after adoption of a gluten-free diet the serum autoantibodies disappear from the circulation more rapidly than the small-intestinal mucosal autoantibody deposits. The finding of IgA deposits on extracellular tTG in the liver, kidney, lymph nodes and muscles of patients with CD indicates that tTG is accessible to the gut-derived autoantibodies. Although the specific autoantibody response directed against tTG is very characteristic in celiac patients, their role in the immunopathology of the celiac mucosal lesion is a matter of debate. Here we report a brief summary of anti-tTG antibody effects demonstrating that these antibodies are functional and not mere bystanders in the disease pathogenesis. In fact, they inhibit intestinal epithelial cell differentiation, induce intestinal epithelial cell proliferation, increase epithelial permeability and activate monocytes and disturb angiogenesis.

The present invention describes compounds of formula (I), and in particular the 7- nitro-5-phenyl-1 -(pyrrolidin-1 - ylmethyl)-1 H-benzo[e][1,4]diazepin-2(3H)-one compound and their pharmaceuticall acceptable salts. The compounds of the invention are useful for medical use, particularly as active ingredient potentially useful for the treatment of cerebral ischemia and other disease characterized by deregulation of sodium and calcium homeostasis

The silencing in PC-12 cells or the knocking-out in mice of the ncx3 gene, that encodes for the Na+/Ca2+ exchanger type 3, prevented the enhancement of both I(NCX) and Ca(2+) content in ER stores induced by beta -amyloid 1-42, suggesting that NCX3 was involved in the increase of ER Ca(2+) content stimulated by this peptide. By contrast, in the late phase (72 h), when the NCX3 proteolytic cleavage abruptly decreased, the occurrence of a parallel reduction in ER Ca(2+) content triggered ER stress, as revealed by caspase-12 activation. Concomitantly, the late increase in [Ca(2+)](i) coincided with neuronal death. Interestingly, NCX3 silencing caused an earlier activation of Aβ(1-42)-induced caspase-12. Indeed, in NCX3-silenced neurons, Aβ(1-42) exposure hastened caspase-dependent apoptosis, thus reinforcing neuronal cell death. These results suggest that Aβ(1-42), through Ca(2+)-dependent calpain activation, generates a hyperfunctional form of the Na+/Ca2+ exchanger NCX3 that, by increasing Ca(2+) content into ER, delays caspase-12 activation and thusER-stress and neuronal death.

We evaluated whether changes in expression and activity of the three sodium/calcium exchanger isoforms, NCX1, NCX2 and NCX3 occurred in PC12 cells when the ERK1/2, JNK, and p38 MAPKs were silenced, pharmacologically blocked, or activated with NGF. Several findings suggesting that MAPKs control NCX emerged: (1) A decrease in NCX1 and NCX3 basal expression occurred when JNK or MEK1, the ERK1/2 upstream activator, were pharmacologically blocked, respectively; (2) NGF increased CREB1 and Sp1 binding to ncx1 promoter and in CREB1 binding to two different sequences close to ncx2 transcription start site on genomic DNA; (3) An up-regulation of NCX1 and NCX3, abrogated upon either MEK1 or p38 blockade, and a down-regulation of NCX2, abolished upon p38 blockade, occurred upon NGF-induced MAPK activation. NCX1 up-regulation was abolished upon either CREB1 or Sp1 silencing, whereas NCX2 down-regulation was abrogated only by CREB1 silencing. NCX3 up-regulation was unaffected by CREB1 or Sp1 silencing and abolished upon proteasomal inhibition; (4) Whole-cell Na(+) /Ca(2+) exchange decreased when MEK1 and JNK were blocked and increased when MAPKs were activated by NGF. Collectively, these results demonstrate a MAPK-dependent regulation of NCX expression and activity which could be relevant in mediating some of the effects of MAPKs in neurons.

Lo scopo principale degli autori del presente trattato è stato quello di correlare le conoscenze sempre più approfondite sull’azione molecolare dei farmaci con gli effetti farmacologici esercitati nell’uomo e che costituiscono i presupposti razionali della terapia medica. Uno spazio adeguato è stato inoltre riservato alla trattazione degli aspetti farmacocinetici clinici, delle reazioni avverse e delle interazioni tra i farmaci, che rappresentano un aspetto in continuo divenire e che sono spesso alla base di eventi avversi clinicamente rilevanti.[...] L’ intento del testo è stato quello di fornire un’informazione la più completa possibile con l’inserimento nella trattazione di argomenti che hanno assunto negli ultimi anni particolare rilevanza nel campo delle possibili prospettive terapeutiche più moderne. Nel trattato sono presenti infatti capitoli innovativi quali quello sui Farmaci Biotecnologici a bersaglio definito, sulla Farmacogenetica e sulla Terapia Genica. Completano la trattazione argomenti inerenti gli aspetti socio-sanitari , economici e normativi della Farmacologia contenuti nei capitoli sulla Sperimentazione Clinica dei Farmaci, sulla Farmacoeconomia e sulla Farmacologia del Doping. Infine, in considerazione del largo uso che si fa dei prodotti di origine vegetale , si è ritenuto utile affrontare tale problematica nel capitolo Principi di fitoterapia nella pratica clinica

Full color throughout Ischemic brain damage represents a major source of morbidity and mortality in westernized society and poses a significant financial burden on the health care system. To date, few effective therapies have been realized to treat stroke and promising avenues have not proven clinically useful. Recent evidence, however, suggests that channels, pumps, and ionic exchangers are involved in CNS ischemia and ischemic stroke, but the potential contribution of these channels for curing stroke is far less understood than for many other normal and pathological conditions. New Strategies in Stroke Intervention: Ionic Channels, Pumps, and Transporters analyzes the roles played by targets in stroke development and the potential action of drugs modulating these proteins. This book provides a groundbreaking review of these ionic channels, pumps, and transporters as regulators of neuronal ionic homeostasis, providing a better understanding of ischemic brain disorders and the new pharmacological avenues for a cure. It will be a useful tool for researchers working in this field, and any student interested in the physiological, pathophysiological, and pharmacological features of stroke damage.

Il brevetto riguarda composti di formula (I), ed in particolare 7-nitro-5-fenil-1(pirrolidin-1-ilmetil)-1H-benzo[e][1,4] diazepin-2(3H)-one, e loro sali farmaceuticamente accettabili, per l’uso medico ed in particolare come principio farmacologicamente attivo per il trattamento dell’ischemia cerebrale e di ogni altra patologia caratterizzata dalla perdita del controllo dell’omeostasi degli ioni sodio e calcio.

La presente invenzione riguarda il campo dei profarmaci, utili nel trattamento delle disfunzioni endoteliali e di ogni altra patologia causata da una ridotta disponibilità di arginina e/o di monossido d’azoto. L’Arginina è considerata l’unico precursore fisiologico per la formazione di NO. Essa è classificata come aminoacido semi-essenziale essendo parzialmente assorbita dalla dieta e parzialmente sintetizzata de novo nell’adulto sano (Nutr. Rev. 1976, 34, 307-9; J. parent. Ent. Nutr. 1986, 10, 227-238). Si descrivono esteri dell’arginina (enantiomeri L- e/o D-) con D-galattosio utili come profarmaci dotati di elevata capacità di penetrazione attraverso le membrane cellulari e la barriera ematoencefalica. Gli esteri dell’invenzione, una volta assorbiti, rilasciano gradualmente l’arginina ed assicurano livelli di farmaco prolungati e elevati, generando una risposta terapeutica consistente e prolungata nel tempo. Ulteriori descrizioni Senza limitazione alcuna, ogni malattia che trae beneficio dal trattamento con arginina, è vantaggiosamente trattabile anche con i presenti esteri, i quali permettono una maggiore accessibilità dell’aminoacido nei comparti dell’organismo posti oltre le membrane cellulari e/o la BEE. Gli esteri dell’invenzione sono in grado di attraversare le membrane cellulari e la BEE sfruttando i sistemi di trasporto transmembranali specifici per gli aminoacidi cationici (Y+, B0,+, b0,+ e Y+L). Da un punto di vista tecnico, le metodologie utilizzate per l’ottenimento di questi risultati comprendono sintesi organica, NMR, HPLC-massa, colture cellulari, microscopia convenzionale e confocale. L’esterificazione con galattosio ha permesso l’ottenimento di una maggiore concentrazione di arginina a livello intracellulare e del SNC, facilitandone il passaggio attraverso le membrane plasmatiche e la BEE. Le malattie trattabili con gli esteri della presente invenzione sono in particolare le seguenti. Disfunzioni endoteliali, intendendo con tale termine ogni patologia caratterizzata da una alterata funzionalità dell’endotelio. Esempi di tali disfunzioni sono: insufficienza cardiaca congestizia, aterosclerosi, sindromi coronariche acute, angina pectoris, scompenso cardiaco cronico, ipertensione arteriosa (essenziale, reno-vascolare, gravidica o preclampsia, portale, ecc.). Altre malattie che possono vantaggiosamente essere trattate con gli esteri dell’invenzione sono: diabete, iperammoniemia da insufficienza epatica, disfunzioni erettili, dispermie seminali, in particolare quelle in presenza di oligoastenospermia, oligozoospermia e bradicinesi, patologie collegate ad una ridotta disponibilità di ormone della crescita (ad es. deficit della crescita), patologie collegate ad una ridotta disponibilità di poliamine cerebrali, patologie neurodegenerative quali il Morbo di Alzheimer, il morbo di Parkinson e l’ictus cerebrale, ecc. Grazie all’attività elevata e prolungata nel tempo dei presenti esteri, si è ottenuto il vantaggio di evitare somministrazioni di arginina in dosaggi particolarmente elevati, e/o ripetute a breve frequenza nel tempo, con particolare vantaggio per quei trattamenti di carattere curativo o preventivo che richiedono una terapia prolungata. Inoltre, il superamento della BEE ha permesso di sfruttare efficacemente le azioni dell’arginina per patologie a carico del sistema nervoso centrale e periferico, evitando complicate e fastidiose procedure di somministrazione in-situ. Ulteriore oggetto dell’invenzione sono composizioni farmaceutiche, utili per il trattamento di patologie che beneficiano del trattamento con arginina, caratterizzate dal contenere un estere di arginina e D-galattosio.

The present study explores the hypothesis that the new anti-epileptic drug levetiracetam (LEV) could interfere with the inositol 1,4,5-trisphosphate (IP(3))-dependent release of intracellular Ca(2+) initiated by G(q)-coupled receptor activation, a process that plays a role in triggering and maintaining seizures. We assessed the effect of LEV on the amplitude of [Ca(2+)](i) response to bradykinin (BK) and ATP in single Fura-2/acetoxymethyl ester-loaded PC12 rat pheochromocytoma cells, which express very high levels of LEV binding sites. LEV dose-dependently reduced the [Ca(2+)](i) increase, elicited either by 1 microM BK or by 100 microM ATP (IC(50), 0.39 +/- 0.01 microM for BK and 0.20 +/- 0.01 microM for ATP; Hill coefficients, 1.33 +/- 0.04 for BK and 1.38 +/- 0.06 for ATP). Interestingly, although the discharge of ryanodine stores by a process of calcium-induced calcium release also took place as part of the [Ca(2+)](i) response to BK, LEV inhibitory effect was mainly exerted on the IP(3)-dependent stores. In fact, the drug was still effective after the pharmacological blockade of ryanodine receptors. Furthermore, LEV did not affect Ca(2+) stored in the intracellular deposits since it did not reduce the amplitude of [Ca(2+)](i) response either to thapsigargin or to ionomycin. In conclusion, LEV inhibits Ca(2+) release from the IP(3)-sensitive stores without reducing Ca(2+) storage into these deposits. Because of the relevant implications of IP(3)-dependent Ca(2+) release in neuron excitability and epileptogenesis, this novel effect of LEV could provide a useful insight into the mechanisms underlying its antiepileptic properties

BACKGROUND & AIMS: Severe diarrhea and enteropathy of unknown origin are frequent in patients infected with human immunodeficiency type 1 virus (HIV-1). The HIV-1 transactivating factor protein (Tat) is a key factor in the pathogenesis of acquired immunodeficiency syndrome. We investigated whether Tat could directly induce ion secretion and cell damage in enterocytes. METHODS: Electrical parameters (ion transport studies) were measured in Caco-2 cell monolayers and in human colonic mucosa specimens mounted in Ussing chambers. The effect of Tat on intestinal mucosa integrity was determined by monitoring the transepithelial electrical resistance of Caco-2 cell monolayers. (3)H-thymidine incorporation and cell count were used to evaluate the effect of Tat on cell growth. Intracellular calcium concentrations were measured at the single-cell level using microfluorometry technique. RESULTS: Tat protein induced ion secretion in Caco-2 cells and in human colonic mucosa similar to that induced by bacterial enterotoxins. It also significantly prevented enterocyte proliferation. In both instances, the effect of Tat was maximum at concentrations within the range detected in the sera of HIV-1-infected patients. Anti-Tat antibodies inhibited both effects. Ion secretion and the antiproliferative effects were mediated by L-type Ca(2+) channels. An increase in intracellular calcium concentration in Caco-2 cells was found after addition of Tat. CONCLUSIONS: These results indicate that Tat may be involved in HIV-1-related intestinal disease through direct interaction with enterocytes.