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1.
Neurobiol Dis ; 138: 104791, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32032735

RESUMO

CDKL5 deficiency disorder (CDD) is a rare X-linked neurodevelopmental disorder that is characterised by early-onset seizures, intellectual disability, gross motor impairment, and autistic-like features. CDD is caused by mutations in the cyclin-dependent kinase-like 5 (CDKL5) gene that encodes a serine/threonine kinase with a predominant expression in the brain. Loss of CDKL5 causes neurodevelopmental alterations in vitro and in vivo, including defective dendritic arborisation and spine maturation, which most likely underlie the cognitive defects and autistic features present in humans and mice. Here, we show that treatment with epigallatocathechin-3-gallate (EGCG), the major polyphenol of green tea, can restore defects in dendritic and synaptic development of primary Cdkl5 knockout (KO) neurons. Furthermore, defective synaptic maturation in the hippocampi and cortices of adult Cdkl5-KO mice can be rescued through the intraperitoneal administration of EGCG, which is however not sufficient to normalise behavioural CDKL5-dependent deficits. EGCG is a pleiotropic compound with numerous cellular targets, including the dual-specificity tyrosine-phosphorylation-regulated kinase 1A (DYRK1A) that is selectively inhibited by EGCG. DYRK1A controls dendritic development and spine formation and its deregulation has been implicated in neurodevelopmental and degenerative diseases. Treatment with another DYRK1A inhibitor, harmine, was capable of correcting neuronal CDKL5-dependent defects; moreover, DYRK1A levels were upregulated in primary Cdkl5-KO neurons in concomitance with increased phosphorylation of Tau, a well-accepted DYRK1A substrate. Altogether, our results indicate that DYRK1A deregulation may contribute, at least in part, to the neurodevelopmental alterations caused by CDKL5 deficiency.


Assuntos
Catequina/análogos & derivados , Síndromes Epilépticas/metabolismo , Polifenóis/metabolismo , Espasmos Infantis/metabolismo , Chá/metabolismo , Animais , Encéfalo/metabolismo , Catequina/metabolismo , Hipocampo/metabolismo , Masculino , Camundongos , Camundongos Knockout , Neurônios/metabolismo , Fosforilação , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Tirosina Quinases/metabolismo , Quinases Dyrk
2.
Neuropharmacology ; 164: 107897, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31794725

RESUMO

Mutations in the X-linked cyclin-dependent kinase-like 5 (CDKL5) gene are responsible for the onset of CDKL5 Deficiency Disorder (CDD), a neurological pathology characterised by severe infantile seizures, intellectual disability, impairment of gross motor skills, sleep and gastrointestinal disturbances. CDKL5 is a serine/threonine kinase the molecular network of which is not yet fully understood. Loss of CDKL5 both in vitro and in vivo leads to altered neuronal morphology including axon specification and outgrowth, dendritic arborisation and spine morphology suggesting a link between CDKL5 and the regulation of proper cytoskeleton functioning. Recently, we found that CDKL5 regulates the binding of CLIP170 to microtubules (MT). CLIP170 is a MT-plus end tracking protein (+TIP) that associates with MTs when present in its open, active conformation. Here we present evidence suggesting CLIP170 contributes to neuronal CDKL5-dependent defects and that it represents an important novel druggable target for CDD; indeed, CLIP170 is directly targeted by the neuroactive steroid pregnenolone (PREG), which induces the active conformation of the protein thus promoting MT-dynamics. We here show that PREG and a synthetic derivative pregnenolone-methyl-ether (PME) can restore the MT association of CLIP170 and revert morphological and molecular defects in Cdkl5-KO neurons at different stages of maturation. All together, these findings identify CLIP170 as possible novel druggable target for CDKL5 related disorders providing an intriguing prospective for future disease-modifying drug-based therapies.


Assuntos
Síndromes Epilépticas/tratamento farmacológico , Síndromes Epilépticas/genética , Pregnenolona/uso terapêutico , Espasmos Infantis/tratamento farmacológico , Espasmos Infantis/genética , Animais , Axônios/efeitos dos fármacos , Axônios/ultraestrutura , Células COS , Chlorocebus aethiops , Ensaio Cometa , Dendritos/efeitos dos fármacos , Dendritos/ultraestrutura , Proteína 4 Homóloga a Disks-Large/genética , Proteína 4 Homóloga a Disks-Large/metabolismo , Feminino , Cones de Crescimento/efeitos dos fármacos , Masculino , Camundongos , Camundongos Knockout , Microtúbulos/efeitos dos fármacos , Microtúbulos/patologia , Neurônios/patologia , Gravidez
3.
Endocrinology ; 121(5): 1649-53, 1987 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3117520

RESUMO

Low basal GH secretion and reduced GH responsiveness to different GH secretagogues, including GHRF, have been reported in aged animals and humans. Parallel to the in vivo findings, an impaired GH responsiveness to GHRF is evident in somatotropes from old rats of either sex. We report here that in anterior pituitaries (APs) from aged male and female rats GHRF-induced stimulation of adenylate cyclase (AC) activity was strikingly reduced (male rats, change from baseline 700% in young and 100% in old rats) or lacking (female rats, change from baseline 430% in young and 13% in old rats) when compared to that evoked by GHRF in the APs from young counterparts. Pretreatment with GHRH (5 micrograms/rat iv for 3 days) decreased the high basal AC activity of old male rats [from 33.38 +/- 3.60 to 15.99 +/- 5.75 (SEM) pmol cAMP/min.mg protein], did not alter the GHRF-stimulated rise in AC activity in old male rats, and induced a small but unequivocal rise in AC activity in old female rats (change from baseline 35% vs. 13%, respectively). Pretreatment with GHRF markedly reduced the acute effect of GHRF in the APs from young rats of both sexes (male rats, change from baseline 360% and 700%; female rats, change from baseline 230% and 430% in GHRF-pretreated and control rats, respectively). In parallel studies performed in female rats, it was shown that in vivo pretreatment with GHRF at the same schedule markedly reduced the effect of acute GHRF stimulation on GH secretion from cultured pituitary cells of young rats but left unchanged GHRF-induced stimulation of GH secretion from pituitary cells of old rats. In all, these data suggest that deficiency of endogenous GHRF synthesis and/or release may underlie defective GH secretion in old rats and that a GHRF replacement regimen that reduces the sensitivity of the young somatotrope cells does not alter the sensitivity of (male rats) or exerts a priming effect (female rats) on the old somatotrope cell.


Assuntos
Adenilil Ciclases/metabolismo , Hormônio Liberador de Hormônio do Crescimento/farmacologia , Adeno-Hipófise/crescimento & desenvolvimento , Envelhecimento , Animais , Células Cultivadas , Feminino , Hormônio do Crescimento/metabolismo , Homeostase , Masculino , Adeno-Hipófise/enzimologia , Adeno-Hipófise/metabolismo , Ratos , Ratos Endogâmicos , Fatores Sexuais
4.
Neuropharmacology ; 27(5): 499-505, 1988 May.
Artigo em Inglês | MEDLINE | ID: mdl-2455874

RESUMO

Intravenous administration of acetyl salicylate of lysine, a soluble salt of aspirin, reduced in rats the firing discharge of thalamic neurones, evoked by noxious stimuli. Concomitantly, concentrations of 5-hydroxyindole acetic acid increased, while those of met-enkephalin-like immuno-reactive derivatives were decreased in several areas of the brain. Similar electrophysiological and biochemical responses were obtained by administering tryptophan or 5-hydroxytryptophan plus carbidopa. The effect of aspirin on the evoked firing of the thalamic neurones was counteracted by pretreating the animals with metergoline. On the other hand, naloxone did not antagonize the inhibitory effect of aspirin and 5-hydroxytryptophan on pain-induced neuronal excitation. These data indicate that a serotonin-, but not a naloxone-sensitive opiate mechanism, may be relevant for aspirin-mediated antinociception.


Assuntos
Analgésicos , Aspirina/farmacologia , Encéfalo/metabolismo , Encefalina Metionina/metabolismo , Serotonina/metabolismo , Animais , Aspirina/administração & dosagem , Encéfalo/efeitos dos fármacos , Potenciais Evocados/efeitos dos fármacos , Ácido Hidroxi-Indolacético/metabolismo , Injeções Intravenosas , Masculino , Naloxona/farmacologia , Ratos , Ratos Endogâmicos
5.
J Med Chem ; 24(5): 622-5, 1981 May.
Artigo em Inglês | MEDLINE | ID: mdl-7241521

RESUMO

The synthesis of three oligomeric derivatives of 4-isobutylphenyl-2-propionic acid (ibuprofen), namely, the monoester of tetraethylene glycol (I) and the diesters of poly(oxyethylene) samples having molecular weights of 1000 (+/- 50) and 2000 (+/- 150) (II and III), has been performed via the imidazolide method. The antiinflammatory activity of I-III, and of equivalent amounts of free drug, was determined in the carrageenan-induced rat paw edema assay at different times after oral administration and found to be considerably prolonged in the case of the three derivatives. The lowest molecular weight derivative (I) also had an enhanced initial activity with regard to 4-isobutylphenyl-2-propionic acid. These results were confirmed by measuring the plasma levels of 4-isobutylphenyl-2-propionic acid in rats at different times after oral administration.


Assuntos
Ibuprofeno/análogos & derivados , Animais , Anti-Inflamatórios/síntese química , Fenômenos Químicos , Química , Feminino , Ibuprofeno/síntese química , Ibuprofeno/farmacologia , Cinética , Dose Letal Mediana , Masculino , Camundongos , Ratos
6.
Biomaterials ; 2(1): 49-52, 1981 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7236833

RESUMO

A series of starch-nicotinic acid copolymers with a degree of esterification ranging from about 15% to about 90% was prepared, and the stability in solution of two representative samples of the series was tested. The variation of some physico-chemical characteristics in the series was examined by solubility tests, viscometry and refractometry, and found to be not simply correlatable to the nicotinylation degree.


Assuntos
Ácidos Nicotínicos/administração & dosagem , Polímeros , Amido , Ésteres , Solubilidade , Relação Estrutura-Atividade , Viscosidade
7.
Brain Res ; 473(2): 236-40, 1988 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-2852985

RESUMO

Manganese chloride increased cell mortality when added to human fibroblast cultures. The toxicity of the metal was greatly enhanced by dopamine; this effect was antagonized by the presence in the culture medium of catalase and superoxide dismutase enzymes. Manganese chloride also caused a marked decrease of striatal dopamine concentrations when infused into rat substantia nigra. Manganese neurotoxicity was lowered by pretreating the animals with drugs that reduced striatal dopamine turnover rate. Administration of an antioxidant, such as vitamin E, also partially prevented striatal dopamine decline induced by intranigral manganese infusion. Therefore, the decreased availability or autoxidation of dopamine attenuated manganese neurotoxicity. These findings are in agreement with previous observations suggesting that manganese increases toxic products originating from dopamine catabolism.


Assuntos
Corpo Estriado/patologia , Dopamina/farmacologia , Compostos de Manganês , Intoxicação por Manganês , Neurotoxinas , Animais , Catalase/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Cloretos/toxicidade , Corpo Estriado/efeitos dos fármacos , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Humanos , Lisurida/farmacologia , Lítio/toxicidade , Cloreto de Lítio , Manganês/farmacologia , Metiltirosinas/farmacologia , Níquel/toxicidade , Ratos , Superóxido Dismutase/farmacologia , Vitamina E/farmacologia , alfa-Metiltirosina
8.
Eur J Pharmacol ; 142(3): 425-9, 1987 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-2962879

RESUMO

It has been shown recently that SKF 38393-A (2,3,4,5-tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine-7-ol), a D-1 receptor agonist, possesses a prolactin-releasing effect in the rat, though the pituitary or central nervous system location of the receptors involved has not been clarified. The aim of our study was to elucidate this point. SKF 38393-A administered to freely moving adult female and male rats induced a striking, short-lived increase of basal prolactin levels. The prolactin stimulatory effect of SKF 38393-A was counteracted by pretreatment with SCH 23390, A D-1 receptor blocker. SKF 38393-A (10(-11)-10(-6)M) added to monolayer primary cultures of anterior pituitary cells from rats of both sexes failed to modify prolactin release. At higher concentrations (10(-5)-10(-4) M) the drug induced a slight inhibition of prolactin release. Similarly, SKF 38393-A failed to stimulate adenylate cyclase activity in anterior pituitary membranes from rats of both sexes at low concentrations, while it inhibited enzyme activity at higher concentrations (10(-5)-10(-3) M). The latter effect was counteracted by concomitant addition of the antagonist of D-2 receptors, 1-sulpiride. These data demonstrate that: (1) the anterior pituitary does not contain D-1-dopamine receptors (positively coupled to adenylate cyclase) stimulatory to prolactin release; (2) the striking prolactin-releasing effect of SKF 38393-A in the rat is due to activation of extra-pituitary D-1 dopamine receptors; (3) SKF 38393-A, at high concentrations, is capable of activating pituitary D-2 receptors.


Assuntos
Hipófise/metabolismo , Prolactina/metabolismo , Receptores Dopaminérgicos/fisiologia , 2,3,4,5-Tetra-Hidro-7,8-Di-Hidroxi-1-Fenil-1H-3-Benzazepina , Adenilil Ciclases/metabolismo , Animais , Depressores do Apetite/farmacologia , Benzazepinas/farmacologia , Feminino , Masculino , Técnicas de Cultura de Órgãos , Radioimunoensaio , Ratos , Ratos Endogâmicos , Receptores de Dopamina D1
9.
J Neural Transm Suppl ; 22: 33-45, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-2946813

RESUMO

Unilateral lesions of the nigro-striatal dopamine (DA) pathway induced contralateral rotations to apomorphine, increased (3H)-spiroperidol binding and enhanced the sensitivity of striatal adenylate cyclase to DA stimulation. Prolonged L-dopa administration counteracted the increased density of (3H)-spiroperidol binding sites but further enhanced the hypersensitivity of adenylate cyclase to DA and decreased the inhibitory effect of opiates on this enzyme. The apomorphine-induced contralateral rotations were also strongly potentiated. On the contrary the binding of (3H)-SCH-23390 was affected neither by DA nerve degeneration nor by chronic L-dopa treatment. These results suggest that DA-D1 and DA-D2 receptors are differently affected by prolonged L-dopa treatment. The biochemical changes of DA-D1 receptors associated with adenylate cyclase seem to be correlated with the enhanced behavioural responses to apomorphine and could be a consequence of a decreased opiate inhibitory tone on the enzyme. The increased supersensitivity of the DA-D1 receptors may play a role in the clinical changes seen in parkinsonian patients following chronic use of L-dopa.


Assuntos
Corpo Estriado/efeitos dos fármacos , Levodopa/farmacologia , Receptores Dopaminérgicos/efeitos dos fármacos , Substância Negra/fisiologia , Adenilil Ciclases/metabolismo , Animais , Apomorfina/farmacologia , Benzazepinas/metabolismo , Benzazepinas/farmacologia , Carbidopa/farmacologia , Dopamina/fisiologia , Hidroxidopaminas/farmacologia , Masculino , Oxidopamina , Ratos , Ratos Endogâmicos , Receptores de Dopamina D1 , Espiperona/metabolismo , Comportamento Estereotipado/efeitos dos fármacos , Sulpirida/farmacologia
10.
Minerva Med ; 73(42): 2973-6, 1982 Nov 03.
Artigo em Italiano | MEDLINE | ID: mdl-7133509

RESUMO

A case of inguinogenital gangrene in a 63 years old man is reported. The patient was admitted to the hyperbaric medicine centre in a serious general condition. The use of HOT, antibiotics and selective surgery as treatment of metabolic disturbances effectively improved the patient's general condition, and HOT also proved effective in the treatment of hepatic insufficiency.


Assuntos
Gangrena/terapia , Virilha , Oxigenoterapia Hiperbárica , Infecções por Pseudomonas/terapia , Escroto , Gangrena/etiologia , Gangrena/cirurgia , Gentamicinas/uso terapêutico , Humanos , Lincomicina/uso terapêutico , Cirrose Hepática Alcoólica/complicações , Cirrose Hepática Alcoólica/terapia , Masculino , Pessoa de Meia-Idade , Retalhos Cirúrgicos
11.
Farmaco ; 46(6): 725-42, 1991 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1722978

RESUMO

Although bombesin (BN) and substance P share only the C-terminal dipeptide amide, some substance P receptor antagonists are also weak bombesin receptor antagonists. In order to increase the selectivity of the antagonism for the BN receptor, a series of hybrid peptides were synthesized by the solid-phase methodology, and screened on 3T3 fibroblasts for binding and mitogenic activity. The analogues inhibiting BN-induced thymidine incorporation were further tested for peripheral (amylase release and urinary bladder contraction) and central activity (grooming behaviour).


Assuntos
Receptores de Neurotransmissores/antagonistas & inibidores , Substância P/antagonistas & inibidores , Células 3T3 , Sequência de Aminoácidos , Amilases/metabolismo , Animais , Asseio Animal/efeitos dos fármacos , Técnicas In Vitro , Masculino , Camundongos , Mitógenos/farmacologia , Dados de Sequência Molecular , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Pâncreas/efeitos dos fármacos , Pâncreas/enzimologia , Ratos , Receptores da Bombesina , Receptores da Neurocinina-1 , Bexiga Urinária/efeitos dos fármacos
17.
Cell Biol Int Rep ; 7(2): 161-70, 1983 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-6188544

RESUMO

The 60Sn and 40Sn subunit ribosome synthesis declined significantly in Yoshida rat ascites hepatoma AH-130 cells from the log phase to the plateau phase of the in vivo growth. Two main classes of 40Sn particles with protein/RNA ratios of 1.82 (p2) and 1.20 (p3) and a minor "heavy" one with protein/RNA ratio of 0.96 (p1) could be distinguished reproducibly by their ultraviolet absorption after sucrose zone sedimentation. The p2 particles appeared the dominating class in log phase cells. In plateau phase cells a decrease of p2 and an increase of p3 particles was observed. Under these conditions the p1 particles and the peaks corresponding to 60Sn subunits and to 80S ribosomes were also increased. Newly synthetized 40Sn particles banded in the p3 region of the gradient and p2 particles originated from them. These particles entered into the ribosomal cycle and contained poly(A) RNA. Formation of radioactive 80S couples by subunits entering into the ribosomal cycle was markedly stimulated in log phase cells and almost completely blocked in cells at the plateau phase of growth.


Assuntos
Divisão Celular , Interfase , Ribossomos/metabolismo , Animais , Linhagem Celular , Centrifugação com Gradiente de Concentração , Cinética , Neoplasias Hepáticas Experimentais , Poli A/análise , RNA/análise , RNA Mensageiro , RNA Ribossômico/análise , Ratos , Proteínas Ribossômicas/análise
18.
G Ital Cardiol ; 26(6): 681-7, 1996 Jun.
Artigo em Italiano | MEDLINE | ID: mdl-8803589

RESUMO

Carotid sinus syndrome (SSC) is quite rarely associated with malignancy of the head and neck. We report a case of mixed type of SSC coupled to a left parapharyngeal centroblastic polymorphic non-Hodgkin lymphoma with high degree of histological malignancy. Syncope was the starting symptom and diagnosis, suspected on the ground of objective local signs, was settled by neck CT. Histological identification was performed after the tumor was surgically removed. Paralysis of left vocal cord and left cervical sympathetic nerve resulted associated with disappearance of spontaneous hypotensive events. The complex diagnostic program, often borne by such patients, stimulates to a critical review.


Assuntos
Seio Carotídeo , Linfoma não Hodgkin/complicações , Neoplasias Faríngeas/complicações , Síncope/etiologia , Doenças das Artérias Carótidas/complicações , Doenças das Artérias Carótidas/diagnóstico por imagem , Seio Carotídeo/diagnóstico por imagem , Humanos , Linfoma não Hodgkin/patologia , Masculino , Pessoa de Meia-Idade , Neoplasias Faríngeas/patologia , Radiografia , Síndrome
19.
Pacing Clin Electrophysiol ; 21(10): 1943-8, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9793091

RESUMO

SPEM is a multicenter randomized double-blind study performed to test the acute and chronic electrophysiological behavior of three different ventricular leads: (1) an ion exchange membrane with 30-microgram dexamethasone elution in a contoured activated carbon tip lead (Membrane 1400T, 30 patients); (2) the same lead design without steroid (Membrane 1401T, 24 patients); and (3) the same lead design without steroid or membrane (control group, 27 patients). Twenty-three of the 81 patients were women; the mean age for all patients was 74 +/- 10 years. Parameters are calculated both in uni- and bipolar configuration at implant and at follow-up after 1, 5, 15, 30, 90, 180, and 360 days. Implant threshold (chronaxie = 0.413 +/- 0.280 ms, rheobase = 0.264 +/- 0.099 V), signal amplitude (13.45 +/- 5.87 mV), and slew rate (2.05 +/- 1.38 V/s) reveal no significant differences. Pacing impedance values both at implant (unipolar 571 +/- 165 omega; bipolar 605 +/- 123 omega) and at follow-ups (unipolar 480 +/- 72 omega; bipolar 518 +/- 75 omega) are slightly lower in the unipolar configuration. At 15 and 30-day follow-ups, control group and nonsteroid leads show a higher threshold value growth (in unipolar from 0.16 +/- 0.11 to 1.19 +/- 0.85 microJ; in bipolar from 0.18 +/- 0.13 to 1.24 +/- 0.88 microJ) than the membrane steroid leads (in unipolar from 0.13 +/- 0.11 to 0.70 +/- 0.39 microJ; in bipolar from 0.23 +/- 0.32 to 0.76 +/- 0.36 microJ); the threshold of nonsteroid leads decreases after 1-3 months and it settles at the same threshold level of the leads with membrane and steroid (in unipolar 0.60 +/- 0.33 microJ; in bipolar 0.55 +/- 0.26 microJ), which has been stable since the first month. The ion exchange membrane is effective in reducing the chronic pacing threshold like acute steroid elution at low doses, but membrane alone does not prevent an acute pacing threshold increase through the first month postimplant.


Assuntos
Eletrodos Implantados , Membranas Artificiais , Marca-Passo Artificial , Idoso , Materiais Biocompatíveis , Estimulação Cardíaca Artificial/métodos , Dexametasona/administração & dosagem , Método Duplo-Cego , Impedância Elétrica , Desenho de Equipamento , Feminino , Seguimentos , Glucocorticoides/administração & dosagem , Humanos , Masculino , Fatores de Tempo
20.
G Ital Cardiol ; 9(4): 428-33, 1979.
Artigo em Italiano | MEDLINE | ID: mdl-456804

RESUMO

This report describes a case of Wolff-Parkinson-White syndrome with atrial fibrillation in which the ventricular complexes conducted over the accessory pathway have promptly disappeared with the use of intravenously administered lidocaine. Lidocaine is suggested as the most suitable drug in such situations. Finally possible connections are presented between high dosage administered lidocaine and conversion to normal sinus rhythm.


Assuntos
Fibrilação Atrial/complicações , Lidocaína/uso terapêutico , Síndrome de Wolff-Parkinson-White/complicações , Fibrilação Atrial/tratamento farmacológico , Feminino , Humanos , Pessoa de Meia-Idade , Síndrome de Wolff-Parkinson-White/tratamento farmacológico
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