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1.
Pain Med ; 21(9): 1891-1901, 2020 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-31617931

RESUMEN

BACKGROUND: Tapentadol is a molecule incorporating mu opioid receptor agonism and norepinephrine reuptake inhibition to provide analgesia, with the potential for a lower incidence of gastrointestinal side effects than full mu opioid agonists. Postmarketing surveillance of tapentadol as an active pharmaceutical ingredient has consistently revealed low levels of abuse and diversion. OBJECTIVE: The purpose of the present study was to further characterize the abuse liability of tapentadol extended-release (ER) by evaluating the prevalence of past 30-day tapentadol ER abuse and reported routes of administration as compared with ER opioids with Food and Drug Administration (FDA) abuse-deterrent labeling ("ADF opioids") and ER opioids without FDA abuse-deterrent labeling ("non-ADF opioids"). METHODS: Data were collected from January 2014 through December 2017 from 776 centers located in 43 states throughout the United States using the Addiction Severity Index-Multimedia Version (ASI-MV), an instrument that is integral to the National Addictions Vigilance Intervention and Prevention Program (NAVIPPRO, Inflexxion, an IBH Company, Costa Mesa, CA, USA). RESULTS: Tapentadol ER had lower rates of past 30-day abuse than ADF ER and non-ADF ER opioid comparators, both at a population level and when adjusted for drug utilization. Tapentadol ER was primarily abused orally, although it was also abused through alternate routes of administration. Cumulative rates of tapentadol ER abuse by alternative routes of administration were lower than both ADF and non-ADF ER opioid comparators, although large confidence intervals resulting from the small sample size of reported tapentadol ER use limit firm conclusions. CONCLUSIONS: In summary, tapentadol ER was found to have lower rates of both past 30-day abuse and use via alternate routes of administration, specifically snorting and smoking, than ADF and non-ADF ER comparators.


Asunto(s)
Multimedia , Trastornos Relacionados con Opioides , Analgésicos Opioides/uso terapéutico , Preparaciones de Acción Retardada , Humanos , Trastornos Relacionados con Opioides/tratamiento farmacológico , Trastornos Relacionados con Opioides/epidemiología , Prevalencia , Tapentadol , Estados Unidos
2.
Mol Vis ; 18: 2153-64, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22879735

RESUMEN

PURPOSE: To explore whether, following direct contact, there is mutual influence between pericytes (PC) and endothelial cells (EC), and to establish whether protein kinase C (PKC) activation, a condition associated with hyperglycemia, can affect, via the mRNA-binding Hu-antigen R (HuR)/ELAV protein, the expression of vascular endothelial growth factor (VEGF). METHODS: PC and EC were cultured separately or in direct contact (1:1 ratio), and exposed or not to phorbol esters, a PKC activator (100 nM for 15 min). Barrier integrity was evaluated by measuring endothelial electrical resistance and permeability to sodium fluorescein. Immunocytochemistry was performed to visualize EC and PC in coculture, and to evaluate phorbol 12-myristate-13-acetate (PMA)-induced HuR translocation. PKCßI/ßII, HuR, and VEGF protein content was measured with western blotting, VEGF secretion in cell culture medium was evaluated with enzyme-linked immunosorbent assay (ELISA), and quantification of VEGF mRNA was performed with real-time quantitative PCR. RESULTS: In monocultures, VEGF mRNA/protein basal levels were more elevated in PC than in EC. However, the basal expression of VEGF protein, but not mRNA, in PC and EC was affected by culture conditions. In fact, physical contact with PC upregulated VEGF protein levels in the EC, while VEGF was downregulated in PC cocultured with EC. In this last condition, PKCßII and HuR protein basal levels were also decreased in monocultured PC. Moreover, in basal conditions, the amount of VEGF released from the coculture was higher than from the monocultures. Direct activation of PKCß induced HuR translocation from the nuclear area to the cytoplasm, and increased the protein levels of the kinase itself, HuR, and VEGF in PC and EC in both culture conditions. Concerning VEGF mRNA, PKC activation induced an increase in PKC levels only in monocultured EC and, conversely, a significant decrease in the same transcript amount in cocultured PC. PMA stimulus also led to a significant increase in VEGF secretion in coculture. CONCLUSIONS: When cocultured with PC, EC form a significantly tighter barrier than the endothelial monolayer. The physical contact leads to opposite changes in VEGF protein levels in PC and EC. In particular, in basal conditions, cocultured PC seemed to downregulate their own expression of this proproliferating factor, as well as that of PKCßII and HuR, likely to maintain the 1:1 ratio with the cohabiting EC. In mono- and cocultured PC/EC, PKC direct activation led to a similar increase in PKCßI/ßII, HuR, and VEGF protein levels, changes that may also occur at early stages of diabetic retinopathy. The release of VEGF in the medium was favored by physical contact between PC and EC and was further increased by PMA exposure. In contrast with the effects on VEGF protein, PKCß activation induced modifications in VEGF mRNA content that are different in function of the cell type and the culture conditions. These findings suggest that the changes in the VEGF protein and transcript observed in PC/EC can be ascribed to distinct and concomitant pathways. Further studies on this in vitro coculture model would be useful to better understand the PC/EC interaction in physiologic and pathological conditions.


Asunto(s)
Proteínas ELAV/metabolismo , Células Endoteliales/metabolismo , Pericitos/metabolismo , Proteína Quinasa C/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Animales , Bovinos , Permeabilidad de la Membrana Celular/efectos de los fármacos , Técnicas de Cocultivo , Cámaras de Difusión de Cultivos , Proteínas ELAV/genética , Células Endoteliales/citología , Células Endoteliales/efectos de los fármacos , Ensayo de Inmunoadsorción Enzimática , Expresión Génica/efectos de los fármacos , Pericitos/citología , Pericitos/efectos de los fármacos , Cultivo Primario de Células , Proteína Quinasa C/genética , Proteína Quinasa C beta , Transporte de Proteínas/efectos de los fármacos , Reacción en Cadena en Tiempo Real de la Polimerasa , Retina/citología , Retina/efectos de los fármacos , Retina/metabolismo , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Acetato de Tetradecanoilforbol/farmacología , Factor A de Crecimiento Endotelial Vascular/genética
3.
Front Pharmacol ; 13: 951833, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36046820

RESUMEN

Diabetic retinopathy (DR), one of the most common complications of diabetes mellitus, is characterized by degeneration of retinal neurons and neoangiogenesis. Until today, the pharmacological approaches for DR are limited and focused on counteracting the end-stage of this neurodegenerative disease, therefore efforts should be carried out to discover novel pharmacological targets useful to prevent DR development. Hyperglycemia is a major risk factor for endothelial dysfunction and vascular complication, which subsequently may trigger neurodegeneration. We previously demonstrated that, in the rat retina, hyperglycemia activates a new molecular cascade implicating, up-stream, protein kinase C ßII (PKC ßII), which in turn leads to a higher expression of vascular endothelial growth factor (VEGF), via the mRNA-binding Hu-antigen R (HuR) protein. VEGF is a pivotal mediator of neovascularization and a well-known vasopermeability factor. Blocking the increase of VEGF via modulation of this cascade can thus represent a new pharmacological option to prevent DR progression. To this aim, proper in vitro models are crucial for drug discovery, as they allow to better identify promising effective molecules. Considering that endothelial cells are key elements in DR and that hyperglycemia triggers the PKCßII/HuR/VEGF pathway, we set up two distinct in vitro models applying two different stimuli. Namely, human umbilical vein endothelial cells were exposed to phorbol 12-myristate 13-acetate, which mimics diacylglycerol whose synthesis is triggered by diabetic hyperglycemia, while human retinal endothelial cells were treated with high glucose for different times. After selecting the optimal experimental conditions able to determine an increased VEGF production, in search of molecules useful to prevent DR development, we investigated the capability of troxerutin, an antioxidant flavonoid, to counteract not only the rise of VEGF but also the activation of the PKCßII/HuR cascade in both in vitro models. The results show the capability of troxerutin to hinder the hyperglycemia-induced increase in VEGF in both models through PKCßII/HuR pathway modulation. Further, these data confirm the key engagement of this cascade as an early event triggered by hyperglycemia to promote VEGF expression. Finally, the present findings also suggest the potential use of troxerutin as a preventive treatment during the early phases of DR.

4.
Mol Psychiatry ; 13(6): 641-7, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17684496

RESUMEN

The identification of biological markers of Alzheimer's disease (AD) can be extremely useful to improve diagnostic accuracy and/or to monitor the efficacy of putative therapies. In this regard, peripheral cells may be of great importance, because of their easy accessibility. After subjects were grouped according to diagnosis, the expression of conformationally mutant p53 in blood cells was compared by immunoprecipitation or by a cytofluorimetric assay. In total, 104 patients with AD, 92 age-matched controls, 15 patients with Parkinson's disease and 9 with other types of dementia were analyzed. Two independent methods to evaluate the differential expression of a conformational mutant p53 were developed. Mononuclear cells were analyzed by immunoprecipitation or by flow-cytometric analysis, following incubation with a conformation-specific p53 antibody, which discriminates unfolded p53 tertiary structure. Mononuclear cells from AD patients express a higher amount of mutant-like p53 compared to non-AD subjects, thus supporting the study of conformational mutant p53 as a new putative marker to discriminate AD from non-AD patients. We also observed a strong positive correlation between the expression of p53 and the age of patients. The expression of p53 was independent from the length of illness and from the Mini Mental State Examination value.


Asunto(s)
Enfermedad de Alzheimer/genética , Proteína p53 Supresora de Tumor/química , Proteína p53 Supresora de Tumor/genética , Anciano , Anciano de 80 o más Años , Envejecimiento/genética , ADN/sangre , ADN/genética , ADN/aislamiento & purificación , Demencia/sangre , Demencia/genética , Citometría de Flujo , Humanos , Italia , Leucocitos , Enfermedad de Parkinson/sangre , Enfermedad de Parkinson/genética , Polonia , Conformación Proteica , Valores de Referencia , Proteína p53 Supresora de Tumor/sangre
5.
Science ; 252(5011): 1421-4, 1991 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-17772917

RESUMEN

By means of controlled collisions of atoms and molecules with liquid surfaces, molecular beam experiments can be used to probe how gases stick to, rebound from, and exchange energy with molecules in the liquid phase. This report describes measurements of energy exchange in collisions between gases (neon, xenon, and sulfur hexafluoride) and polyatomic liquids (squalane and perfluoropolyether). Energy transfer depends critically on liquid composition and is more efficient for the hydrocarbon than for the perfluorinated ether.

6.
IEEE Trans Inf Technol Biomed ; 12(1): 94-9, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18270041

RESUMEN

An electronic health record depends on the consistent handling of people's identities within and outside healthcare organizations. Currently, the Person Identification Service (PIDS), a CORBA specification, is the only well-researched standard that meets these needs. In this paper, we introduce WS/PIDS, a PIDS specification for Web Services (WS) that closely matches the original PIDS and improves on it by providing explicit support for medical multimedia attributes. WS/PIDS is currently supported by a test implementation, layered on top of a PIDS back-end, with Java- and NET-based, and Web clients. WS/PIDS is interoperable among platforms; it preserves PIDS semantics to a large extent, and it is intended to be fully compliant with established and emerging WS standards. The specification is open source and immediately usable in dynamic clinical systems participating in grid environments. WS/PIDS has been tested successfully with a comprehensive set of use cases, and it is being used in a clinical research setting.


Asunto(s)
Internet , Sistemas de Registros Médicos Computarizados , Adhesión a Directriz
7.
Neuroscience ; 147(3): 652-63, 2007 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-17560043

RESUMEN

Several studies suggest a pivotal role of amyloid beta (Abeta)(1-42) and nitric oxide (NO) in the pathogenesis of Alzheimer's disease. NO also possess central neuromodulatory properties. To study the soluble Abeta(1-42) effects on dopamine concentrations in rat prefrontal cortex, microdialysis technique was used. We showed that i.c.v. injection or retrodialysis Abeta(1-42) administration reduced basal and K(+)-stimulated dopamine levels, measured 2 and 48 h after peptide administration. Immunofluorescent experiments revealed that after 48 h from i.c.v. injection Abeta(1-42) was no longer detectable in the ventricular space. We then evaluated the role of NO on Abeta(1-42)-induced reduction in dopamine concentrations. Subchronic L-arginine administration decreased basal dopamine levels, measured either 2 h after i.c.v. Abeta(1-42) or on day 2 post-injection, whereas subchronic 7-nitroindazole administration increased basal dopamine concentrations, measured 2 h after i.c.v. Abeta(1-42) injection, and decreased them when measured on day 2 post-Abeta(1-42)-injection. No dopaminergic response activity was observed after K(+) stimulation in all groups. These results suggest that the dopaminergic system seems to be acutely vulnerable to soluble Abeta(1-42) effects. Finally, the opposite role of NO occurring at different phases might be regarded as a possible link between Abeta(1-42)-induced effects and dopaminergic dysfunction.


Asunto(s)
Péptidos beta-Amiloides/farmacología , Dopamina/metabolismo , Óxido Nítrico/fisiología , Fragmentos de Péptidos/farmacología , Corteza Prefrontal/efectos de los fármacos , Análisis de Varianza , Animales , Arginina/farmacología , Interacciones Farmacológicas , Inhibidores Enzimáticos/farmacología , Indazoles/farmacología , Masculino , Microdiálisis/métodos , Ratas , Ratas Wistar , Factores de Tiempo
8.
Trends Neurosci ; 20(9): 410-5, 1997 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9292970

RESUMEN

High levels of expression of Ca2+/phospholipid-dependent protein kinase C (PKC) occur in neuronal tissues and play a strategic role in the modulation of short- and long-term functions (ion channels, receptor desensitization, neurotransmitter release and synaptic efficiency) that become modified during the brain ageing process. Recent studies have clarified the key role played by the anchoring proteins in mediating subcellular PKC location, that is, in driving the enzyme to specific sites of action. The protein, receptor for activated C-kinase 1 (RACK1) is involved in PKC-mediated signal transduction. A postnatal developmental increase in RACK1 levels indicates their significance in the outgrowth of neuronal processes. In a physiological model of impairment in PKC translocation-the aged rat brain cortex-RACK1 levels are reduced and the PKC isoenzymes known to interact with it do not translocate to membrane compartments upon stimulation. Anchoring proteins might represent new targets for compounds that modulate PKC signal transduction processes.


Asunto(s)
Envejecimiento/fisiología , Encéfalo/enzimología , Péptidos/fisiología , Proteína Quinasa C/metabolismo , Receptores de Superficie Celular/fisiología , Animales , Encéfalo/crecimiento & desarrollo , Encéfalo/fisiología , Activación Enzimática/fisiología , Humanos , Péptidos/metabolismo , Ratas , Receptores de Cinasa C Activada , Receptores de Superficie Celular/metabolismo
9.
Minerva Med ; 97(2): 147-51, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16760853

RESUMEN

AIM: Weight gain and the risk of developing alterations in lipid and glucose metabolism are possible side effects of atypical antipsychotic therapy in young and adult patients. The objective of this study was to examine whether elderly patients with Alzheimer's disease (AD) gain weight or develop disturbances in lipid and glucose metabolism while being treated with atypical antipsychotic drugs. METHODS: This retrospective study identified 36 out of 99 patients (mean age: 75.4+/-7.1, 27 female, 9 males) who were taking risperidone (N=9, mean dosage: 1.42+/-0.49 mg/day), olanzapine (N=17: 4.42+/-1.10 mg/day), and quetiapine (N=10: 75+/-27 mg/day) over a 12 months period. Anthropometric parameters, mini nutritional assessment (MNA), total, HDL and LDL cholesterol, triglycerides, glycaemia were assessed at baseline (T0) and 12 (T1) months. RESULTS: Body weight (BMI=23+/-5 vs 23+/-5), MNA score (21+/-4 vs 21+/-4), blood glucose (5.7+/-2 vs 4.9+/-0.9 mmol/L) or total cholesterol (4.9+/-1.1 vs 4.3+/-0.7 mmol/L), HDL cholesterol (1.3+/-0.3 vs 1.1+/-0.3 mmol/L), LDL cholesterol (3.3+/-0.7 vs 3 +/- 0.4 mmol/L), triglycerides (1.1+/-0 vs 1+/-0.3 mmol/L) did not reveal treatment-induced changes in the patients evaluated (T0 vs T1). CONCLUSION: These results suggest that the treatment with low-dose of atypical antipsychotic drugs is not associated with weight gain or increase the risk of developing type II diabetes or abnormalities of lipid metabolism among elderly patients with AD, who were residing in long-term nursing home.


Asunto(s)
Enfermedad de Alzheimer/psicología , Antipsicóticos/efectos adversos , Glucemia/efectos de los fármacos , Lípidos/sangre , Aumento de Peso , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/sangre , Benzodiazepinas/efectos adversos , Dibenzotiazepinas/efectos adversos , Femenino , Humanos , Masculino , Trastornos Mentales/tratamiento farmacológico , Casas de Salud , Olanzapina , Fumarato de Quetiapina , Estudios Retrospectivos , Risperidona/efectos adversos
10.
J Neuroimmunol ; 298: 189-93, 2016 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-27609295

RESUMEN

Immune-mediated and neurodegenerative mechanisms are involved in multiple sclerosis (MS). Growing evidences highlight the role of HSP70 genes in the susceptibility of some neurological diseases. In this explorative study we analyzed a polymorphism (i.e. HSP70-hom rs2227956) of the gene HSPA1L, which encodes for the protein hsp70-hom. We sequenced the polymorphism by polymerase chain reaction (PCR), in 191 MS patients and 365 healthy controls. The hsp70-hom protein expression was quantified by western blotting. We reported a strong association between rs2227956 polymorphism and MS risk, which is independent from the association with HSP70-2 rs1061581, and a significant link between hsp70-hom protein expression and MS severity.


Asunto(s)
Predisposición Genética a la Enfermedad/genética , Proteínas HSP70 de Choque Térmico/genética , Proteínas HSP70 de Choque Térmico/metabolismo , Esclerosis Múltiple/genética , Esclerosis Múltiple/metabolismo , Polimorfismo Genético/genética , Adulto , Evaluación de la Discapacidad , Femenino , Frecuencia de los Genes , Genotipo , Humanos , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/metabolismo , Funciones de Verosimilitud , Masculino , Escala del Estado Mental , Persona de Mediana Edad
11.
J Neurosci ; 20(10): 3705-13, 2000 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-10804212

RESUMEN

Expansion of a polyglutamine sequence in the N terminus of huntingtin is the gain-of-function event that causes Huntington's disease. This mutation affects primarily the medium-size spiny neurons of the striatum. Huntingtin is expressed in many neuronal and non-neuronal cell types, implying a more general function for the wild-type protein. Here we report that wild-type huntingtin acts by protecting CNS cells from a variety of apoptotic stimuli, including serum withdrawal, death receptors, and pro-apoptotic Bcl-2 homologs. This protection may take place at the level of caspase-9 activation. The full-length protein also modulates the toxicity of the poly-Q expansion. Cells expressing full-length mutant protein are susceptible to fewer death stimuli than cells expressing truncated mutant huntingtin.


Asunto(s)
Apoptosis/fisiología , Caspasas/metabolismo , Proteínas del Tejido Nervioso/genética , Neuronas/citología , Neuronas/enzimología , Proteínas Nucleares/genética , Animales , Caspasa 3 , Caspasa 9 , Línea Celular Transformada , Supervivencia Celular/fisiología , Corteza Cerebral/citología , Cuerpo Estriado/citología , Regulación Enzimológica de la Expresión Génica , Etiquetado Corte-Fin in Situ , Mutagénesis/fisiología , Neuronas/química , Regiones Promotoras Genéticas/fisiología , Proteínas Proto-Oncogénicas c-bcl-2/genética , Transfección , Proteína bcl-X
12.
Trends Pharmacol Sci ; 20(10): 418-23, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10498955

RESUMEN

The treatment of Alzheimer's disease remains a major challenge because of our incomplete understanding of the triggering events that lead to the selective neurodegeneration characteristic of Alzheimer's brains. The rational design of a pharmacological intervention is therefore a great theoretical challenge. One approach involves the study of the pharmacological modulation of the amyloid precursor protein metabolism, in which the goal is to reduce the formation of beta-amyloid in the hope of reducing the formation of a potentially neurotoxic peptide. Such an approach has led to the identification of a complex intracellular mechanism that can be regulated by neurotransmitters and other ligands.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/biosíntesis , Fármacos Neuroprotectores/farmacología , Secuencia de Aminoácidos , Animales , Humanos , Datos de Secuencia Molecular
13.
J Cereb Blood Flow Metab ; 8(1): 96-9, 1988 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2448324

RESUMEN

Increasing evidence suggests a role for calcium ions in the pathophysiology of ischemic brain damage. The major mechanism allowing calcium entry from the extracellular compartment is the opening of voltage-operated calcium channels. In this line, we have explored the hypothesis that the characteristics of central L-type voltage-dependent calcium channels, labeled by the dihydropyridine ligand 3H-PN 200-110, may be modified by experimental ischemia. The results show that short-term mild ischemia, produced in the rat by 1 h of right carotid ligation, induces an increase in the number of 3H-PN 200-110 binding sites in the hippocampus ipsilateral to the side of carotid occlusion, accompanied by an increase in the dissociation constant value, whereas no changes in the kinetic parameters of the binding were observed in the other areas examined, i.e., the cortex and the striatum. The changes in hippocampus are transient: 96 h after the occlusion, binding parameters return to the control range. The modifications of the binding characteristics in the hippocampus may be related to alterations of Ca2+ fluxes through L-type calcium channels.


Asunto(s)
Calcio/metabolismo , Hipocampo/metabolismo , Canales Iónicos/metabolismo , Ataque Isquémico Transitorio/metabolismo , Animales , Bloqueadores de los Canales de Calcio , Membrana Celular/metabolismo , Corteza Cerebral/metabolismo , Cuerpo Estriado/metabolismo , Isradipino , Cinética , Masculino , Oxadiazoles/metabolismo , Ratas , Ratas Endogámicas
14.
Neurobiol Aging ; 8(4): 355-7, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-2442637

RESUMEN

Drugs acting on neuronal calcium homeostasis may potentially affect the aging brain, but the risk/benefit ratio of this approach should be carefully evaluated.


Asunto(s)
Envejecimiento/metabolismo , Encéfalo/metabolismo , Bloqueadores de los Canales de Calcio/uso terapéutico , Trastornos del Metabolismo del Calcio/tratamiento farmacológico , Anciano , Envejecimiento/fisiología , Encéfalo/fisiopatología , Homeostasis , Humanos , Canales Iónicos/fisiología
15.
Neurobiol Aging ; 15(2): 203-6, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7838292

RESUMEN

Intracellular Ca2+ release channels are key players in the regulation of Ca2+ homeostasis. In the present study, we investigated the age-related changes of inositol 1,4,5-trisphosphate (IP3) receptor/Ca2+ release channel and ryanodine receptor/Ca2+ release channel in microsomes derived from either cerebellum or cerebrum cortex from male Wistar rats. A significant reduction (about 50%) in density of IP3 receptor/Ca2+ release channels was observed in cerebrum cortex, only, in 8- and 28-month old rats, whereas density and Kd of ryanodine binding sites were unaffected in both cerebellum and cerebrum microsomes. These findings, along with impairment of Ca(2+)-dependent protein kinase C phosphorylation of endogeneous substrates, point to coordinate, quantitative alterations of both targets of phosphoinositide metabolism, i.e., PKC and IP3 receptor, in the cerebrum cortex at least. The relevance of the present findings is discussed in relation to reported changes of neuronal Ca2+ homeostasis during aging.


Asunto(s)
Envejecimiento/metabolismo , Química Encefálica/fisiología , Canales de Calcio/metabolismo , Inositol 1,4,5-Trifosfato/metabolismo , Proteínas Musculares/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismo , Animales , Western Blotting , Calcio/metabolismo , Cerebelo/enzimología , Cerebelo/metabolismo , Corteza Cerebral/enzimología , Corteza Cerebral/metabolismo , Electroforesis en Gel de Poliacrilamida , Receptores de Inositol 1,4,5-Trifosfato , Masculino , Microsomas/metabolismo , Proteína Quinasa C/metabolismo , Ratas , Ratas Wistar , Canal Liberador de Calcio Receptor de Rianodina
16.
Neurobiol Aging ; 4(2): 147-49, 1983.
Artículo en Inglés | MEDLINE | ID: mdl-6633783

RESUMEN

Enkephalin like peptides seem to have an important regulatory role at ganglia level. The aim of the present study is to investigate whether the content of enkephalin-like peptides in sympathetic ganglia is affected by the aging process. The results show that the enkephalin like peptides content is low in superior cervical and coeliac ganglia of aged rats (25 months). The age-related decrease of enkephalin content in these structures may be of importance in determining an altered sympathetic control during aging.


Asunto(s)
Encefalina Metionina/análogos & derivados , Ganglios Simpáticos/análisis , Factores de Edad , Animales , Encefalina Metionina/análisis , Masculino , Peso Molecular , Péptidos/análisis , Ratas , Ratas Endogámicas
17.
Neurobiol Aging ; 2(3): 229-31, 1981.
Artículo en Inglés | MEDLINE | ID: mdl-6273758

RESUMEN

Parameters of dopaminergic transmission were studied in the retina of mature (3-4 months) and aged (23-24 months) rats. In the retina of senescent rats were found significantly higher dihydroxyphenylacetic acid (DOPAC) levels and a higher number of (3H-)spiroperidol binding sites. We detected also an increase of (3H)- methionine-enkephalin binding sites. The changes in the density of (3H)-spiroperidol and (3H)-Metenkephalin binding sites in the retina are opposite to those observed in the brain of aged rats.


Asunto(s)
Ácido 3,4-Dihidroxifenilacético/análisis , Envejecimiento , Fenilacetatos/análisis , Receptores Dopaminérgicos/análisis , Retina/fisiología , Animales , Sitios de Unión , Cuerpo Estriado/análisis , Cuerpo Estriado/fisiología , Encefalinas/análisis , Masculino , Ratas , Receptores Opioides/análisis , Retina/análisis
18.
Neurobiol Aging ; 11(5): 563-6, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2234288

RESUMEN

Protein kinase C (PKC) function was analyzed in aged male Sprague-Dawley rat brain using two different approaches: the binding of [3H]-phorbol-12,13-dibutyrate and the in vitro phosphorylation of histone H1. In cortex the binding was decreased while in cerebellum no age-related modifications were observed. In hippocampus the binding capacity was increased in old animals and the affinity decreased. The kinase activity in both soluble and particulate fractions was decreased in cortex, increased in hippocampus and unmodified in cerebellum. The area selective, age-dependent modifications in neuronal PKC may sustain short- and long-term regional changes of neuronal excitability.


Asunto(s)
Envejecimiento/metabolismo , Encéfalo/metabolismo , Ésteres del Forbol/metabolismo , Proteína Quinasa C/metabolismo , Factores de Edad , Animales , Sitios de Unión , Masculino , Ratas , Ratas Endogámicas
19.
Neurobiol Aging ; 11(4): 433-6, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2166240

RESUMEN

Omegaconotoxin binding was studied in young (3 months) and old (24 months) male Sprague-Dawley rats. In both groups omegaconotoxin binding displayed high affinity, was specific and saturable. The age-related changes are mainly a decrease in the Bmax in striatum and cortex (-29% and -31%, respectively). Binding parameters were unmodified in hippocampus of the two age groups. These data are consistent with the decrease of calcium uptake and neurotransmitter release observed in the brain of aged rodents.


Asunto(s)
Envejecimiento/metabolismo , Encéfalo/metabolismo , Péptidos Cíclicos/metabolismo , omega-Conotoxinas , Factores de Edad , Animales , Sitios de Unión , Canales de Calcio/metabolismo , Corteza Cerebral/metabolismo , Cuerpo Estriado/metabolismo , Hipocampo/metabolismo , Masculino , Ratas , Ratas Endogámicas
20.
Neurobiol Aging ; 19(3): 191-9, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9661993

RESUMEN

Increased cytokine-mediated cytotoxic natural killer (NK) cell activity has recently been demonstrated in patients with senile dementia of the Alzheimer's type (SDAT). In the present study, we evaluated whether protein-kinase C (PKC), a main regulatory enzyme involved in the mechanism of exocytosis by NK cells, has a role in the cytotoxic response of NK cells (during IL-2 and IFN-beta exposure) from SDAT patients. Our data demonstrate the presence of an increased cytotoxic response by NK cells to IL-2 (mean increase +102%) and IFN-beta (mean increase +132%) in SDAT patients in comparison with healthy elderly subjects (+75% and +88% for IL-2 and IFN-beta, respectively). A smaller suppression of NK cytotoxicity after cortisol was also observed in SDAT (mean decrease -24%) than in the control group (-44%). The NK cell activity of SDAT patients was inversely correlated with the cognitive status as evaluated by the analysis of MMSE (Mini Mental State Examination) score. A comparison of young and elderly healthy subjects revealed no variations in NK cell activity. A physiological decrease in cytosolic PKC activity was demonstrated in healthy old subjects after IL-2 and IFN-beta incubation, but not in SDAT patients, while no variations in kinase activity were observed after cortisol incubation. The decreased activity with cytokines was associated with reduced levels of PKC alpha and betaII isoforms. An alteration in cytokine-mediated NK cell activity associated with PKC dysregulation is therefore suggested to occur in patients with SDAT. These changes may indicate the existence of an immunological component to the pathogenesis and progression of the disease.


Asunto(s)
Enfermedad de Alzheimer/enzimología , Enfermedad de Alzheimer/inmunología , Citotoxicidad Celular Dependiente de Anticuerpos/fisiología , Células Asesinas Naturales/enzimología , Células Asesinas Naturales/inmunología , Proteína Quinasa C/metabolismo , Adulto , Anciano , Western Blotting , Femenino , Humanos , Hidrocortisona/farmacología , Técnicas In Vitro , Interferón beta/farmacología , Interleucina-2/farmacología , Leucemia Mieloide/patología , Masculino , Transducción de Señal , Células Tumorales Cultivadas
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