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1.
Front Pharmacol ; 14: 1296577, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38152694

RESUMEN

Chronic migraine is a disabling neurovascular disorder that ranks amongst the top causes of years lived with disability worldwide. The duration and the frequency of migraine affect cognitive and affective domains, inducing worsening of memory, executive functions, orientation and causing anxiety. Population-based studies report a worrying level of resistance to treatments. Therefore, this study aims: 1) to assess efficacy of monoclonal antibodies (mAbs) directed towards the calcitonin gene-related peptide (CGRP) or its receptor (CGRP-R) for chronic migraine resistant to current preventatives; 2) to design a clinical trial protocol to evaluate the efficacy and safety of combination therapy utilizing anti-CGRP/CGRP-R together with onabotulinumtoxin A in patients suffering from resistant chronic migraine; 3) to provide a molecular rationale for combination therapy. A controlled trial is warranted as pooled analysis of real-world data from our group highlighted that combined treatment provides ≥50% reduction vs. baseline (onabotulinumtoxin A) of monthly headache days (MHDs) in up to 58.8% of patients, but there has been only sparse application of this combined therapy to date. The mAbs chosen are: erenumab, because its combination effect with onabotulinumtoxin A improved symptoms in 65% of patients; eptinezumab, due to its faster action. The results highlight that early diagnosis of migraine improves therapeutic outcomes with mAbs alone, confirming their effectiveness and the need for an adequately powered clinical trial evaluating the safety and potential superior effectiveness of eptinezumab/erenumab and onabotulinumtoxin A together.

2.
Biomed Pharmacother ; 153: 113488, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36076584

RESUMEN

Up to 80 % nursing home residents with dementia experiences chronic pain. Contextually, 97 % presents fluctuant neuropsychiatric symptoms (NPS). Among the most challenging is agitation, connected with undertreated pain and managed through neuroleptics doubling death risk. Evidence is accumulating in favor of the involvement of the endocannabinoid system in nociception and NPS. This double-blind, placebo-controlled, randomized trial (NAbiximols Clinical Translation To the treatment of Pain and Agitation In Severe Dementia [NACTOPAISD]) aims at investigating efficacy and safety of oral spray nabiximols, containing Δ9-tetrahydrocannabinol and cannabidiol (Sativex®), for pain and agitation treatment in severe dementia patients (Mini-Mental State Examination ≤ 12) over 65. The coprimary endpoints are efficacy on pain and agitation, assessed through the recently validated Italian Mobilization-Observation-Behavior-Intensity-Dementia and the Cohen-Mansfield Agitation Inventory. The secondary endpoint is the evaluation of efficacy duration after wash-out and the assessment of quality of life through the DEMQOL. Any adverse events will be reported. The results undergo statistical analysis plan. NACTOPAISD might provide rationale for a translational safer pain and agitation treatment in severe dementia. It is approved by Calabria Region Ethics Committee and follows the Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) and the Consolidated Standards of Reporting Trials (CONSORT) statements.


Asunto(s)
Cannabidiol , Dolor Crónico , Demencia , Dronabinol , Agitación Psicomotora , Anciano , Cannabidiol/administración & dosificación , Cannabidiol/efectos adversos , Dolor Crónico/tratamiento farmacológico , Dolor Crónico/etiología , Demencia/complicaciones , Demencia/tratamiento farmacológico , Método Doble Ciego , Dronabinol/administración & dosificación , Dronabinol/efectos adversos , Combinación de Medicamentos , Humanos , Vaporizadores Orales , Agitación Psicomotora/tratamiento farmacológico , Agitación Psicomotora/etiología , Ensayos Clínicos Controlados Aleatorios como Asunto
3.
Biomed Pharmacother ; 150: 113013, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35658247

RESUMEN

The 97% of dementia patients develops fluctuant neuropsychiatric symptoms often related to under-diagnosed and unrelieved pain. Up to 80% severe demented nursing home residents experiences chronic pain due to age-related comorbidities. Patients lacking self-report skills risk not to be appropriately treated for pain. Mobilization-Observation-Behavior-Intensity-Dementia (MOBID2) is the sole pain scale to consider the frequent co-occurrence of musculoskeletal and visceral pain and to unravel concealed pain through active guided movements. Accordingly, the Italian real-world setting can benefit from its translation and validation. This clinical study provides a translated, adapted and validated version of the MOBID2, the Italian I-MOBID2. The translation, adaptation and validation of the scale for non-verbal, severe demented patients was conducted according to current guidelines in a cohort of 11 patients over 65 with mini-mental state examination ≤ 12. The I-MOBID2 proves: good face and scale content validity index (0.89); reliable internal consistency (Cronbach's α = 0.751); good to excellent inter-rater (Intraclass correlation coefficient, and test-retest (ICC = 0.902) reliability. The construct validity is high (Rho = 0.748 p < 0.05 for 11 patients, Spearman rank order correlation of the overall pain intensity score with the maximum item score of I-MOBID2 Part 1; rho=0.895 p < 0.01 for 11 patients, for the overall pain intensity score with the maximum item score of I-MOBID2 Part 2) and a good rate of inter-rater and test-retest agreement was demonstrated by Cohen's K = 0.744. The average execution time is of 5.8 min, thus making I-MOBID2 a useful tool suitable also for future development in community setting with administration by caregivers.


Asunto(s)
Dolor Crónico , Demencia , Dolor Crónico/psicología , Demencia/terapia , Humanos , Dimensión del Dolor , Psicometría , Reproducibilidad de los Resultados , Encuestas y Cuestionarios
4.
Cell Death Dis ; 6: e1814, 2015 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-26158520

RESUMEN

Mitochondrial apoptosis-inducing factor (AIF) influences the oxidative phosphorylation (OXPHOS) system and can be recruited as a mediator of cell death. Pathogenic mutations in the AIFM1 gene cause severe human diseases. Clinical manifestations include inherited peripheral neuropathies, prenatal cerebral abnormalities and progressive mitochondrial encephalomyopathies. In humans, rodents and invertebrates, AIF deficiency results in loss of respiratory complexes and, therefore, impaired OXPHOS. The molecular mechanisms underlying AIF-induced mitochondrial dysfunction remain elusive. Here we show that AIF physically interacts with the oxidoreductase CHCHD4/MIA40. In patient-derived fibroblasts as well as in tissues and glia cells from Harlequin (Hq) mutant mice, AIF deficiency correlates with decreased MIA40 protein levels, without affecting mRNA transcription. Importantly, MIA40 overexpression counteracts loss of respiratory subunits in Hq cells. Together, our findings suggest that MIA40 reduction contributes to the effects of AIF deficiency on OXPHOS, as it may impact on the correct assembly and maintenance of the respiratory subunits. This may be relevant for the development of new therapeutic approaches for AIF-related mitochondrial disorders.


Asunto(s)
Factor Inductor de la Apoptosis/genética , Apoptosis/genética , Proteínas de Transporte de Membrana Mitocondrial/genética , Animales , Factor Inductor de la Apoptosis/deficiencia , Humanos , Ratones , Mitocondrias/genética , Mitocondrias/metabolismo , Proteínas del Complejo de Importación de Proteínas Precursoras Mitocondriales , Fosforilación Oxidativa
5.
Cell Death Dis ; 5: e1175, 2014 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-24722300

RESUMEN

Functional neuronal circuits require a constant remodeling of their network composed of highly interconnected neurons. The plasticity of synapses and the shaping of elaborated dendritic branches are energy demanding and therefore depend on an efficient mitochondrial oxidative phosphorylation (OXPHOS). The spatial and functional regulations of dendritic patterning occur also after cell fate specification; however, the molecular mechanisms underlying this complex process remain elusive. Here, we exploit the changes in dendritic architecture in highly branched neurons as a result of aberrant mitochondrial activity. In sensory neurons of Caenorhabditis elegans, genetic manipulations of mitochondrial complex I subunits cause an unexpected outgrowth of dendritic arbors and ectopic structures. The increased number of dendritic branches is coordinated through a specific signaling cascade rather than as a simple consequence of oxidative stress. On the basis of genetic and pharmacological evidence, we show that OXPHOS deficiency promotes branching through the activation of the AMP-activated protein kinase AMPK and the downstream target phosphoinositide 3-kinase PI3K. Taken together, our findings describe a well-defined signaling pathway that regulates dendritic outgrowth in conditions of compromised OXPHOS and the resulting AMPK activation.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Caenorhabditis elegans/citología , Caenorhabditis elegans/enzimología , Dendritas/enzimología , Mitocondrias/metabolismo , Transducción de Señal , Envejecimiento/metabolismo , Animales , Proteínas de Caenorhabditis elegans/metabolismo , Respiración de la Célula , Complejo I de Transporte de Electrón , Activación Enzimática , Fosforilación Oxidativa , Células Receptoras Sensoriales/citología , Células Receptoras Sensoriales/metabolismo
6.
Cell Death Dis ; 2: e228, 2011 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-22071633

RESUMEN

Huntington's disease (HD) is a complex and severe disorder characterized by the gradual and the progressive loss of neurons, predominantly in the striatum, which leads to the typical motor and cognitive impairments associated with this pathology. HD is caused by a highly polymorphic CAG trinucleotide repeat expansion in the exon-1 of the gene encoding for huntingtin protein. Since the first discovery of the huntingtin gene, investigations with a consistent number of in-vitro and in-vivo models have provided insights into the toxic events related to the expression of the mutant protein. In this review, we will summarize the progress made in characterizing the signaling pathways that contribute to neuronal degeneration in HD. We will highlight the age-dependent loss of proteostasis that is primarily responsible for the formation of aggregates observed in HD patients. The most promising molecular targets for the development of pharmacological interventions will also be discussed.


Asunto(s)
Enfermedad de Huntington/patología , Animales , Modelos Animales de Enfermedad , Humanos , Enfermedad de Huntington/metabolismo , Ratones , Degeneración Nerviosa/patología
7.
Cell Death Differ ; 18(2): 191-200, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21217767

RESUMEN

Huntington's disease (HD) is a fatal neurodegenerative disorder caused by expansion of a polyglutamine tract in the huntingtin protein (htt) that mediates formation of intracellular protein aggregates. In the brains of HD patients and HD transgenic mice, accumulation of protein aggregates has been causally linked to lesions in axo-dendritic and synaptic compartments. Here we show that dendritic spines - sites of synaptogenesis - are lost in the proximity of htt aggregates because of functional defects in local endosomal recycling mediated by the Rab11 protein. Impaired exit from recycling endosomes (RE) and association of endocytosed protein with intracellular structures containing htt aggregates was demonstrated in cultured hippocampal neurons cells expressing a mutant htt fragment. Dendrites in hippocampal neurons became dystrophic around enlarged amphisome-like structures positive for Rab11, LC3 and mutant htt aggregates. Furthermore, Rab11 overexpression rescues neurodegeneration and dramatically extends lifespan in a Drosophila model of HD. Our findings are consistent with the model that mutant htt aggregation increases local autophagic activity, thereby sequestering Rab11 and diverting spine-forming cargo from RE into enlarged amphisomes. This mechanism may contribute to the toxicity caused by protein misfolding found in a number of neurodegenerative diseases.


Asunto(s)
Espinas Dendríticas/ultraestructura , Enfermedad de Huntington/metabolismo , Proteínas de Unión al GTP rab/metabolismo , Animales , Espinas Dendríticas/metabolismo , Modelos Animales de Enfermedad , Drosophila/metabolismo , Endosomas/metabolismo , Proteína Huntingtina , Enfermedad de Huntington/patología , Ratones , Ratones Transgénicos , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Neuronas/metabolismo , Neuronas/patología , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Células PC12 , Ratas
8.
Cell Death Differ ; 17(7): 1115-25, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20094060

RESUMEN

As evidence emerges that complex gene alterations are involved in the onset of Parkinson's disease (PD), the role of environmental chemicals in the pathogenesis of this disease becomes intensely debated. Although it is undisputed that acute exposure to certain chemicals such as 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) is sufficient to cause human parkinsonism, the evidence that the risk for PD increases because of environmental exposure is generally weaker. Several studies have suggested that pesticide exposure and life in rural areas are significant risks factors for PD. Among other pesticides, paraquat (PQ) has been linked to PD by epidemiological studies and experimental work in rodents, in which it causes lesions in the substantia nigra, pars compacta. However, the evidence that human exposure to the chemical results in an increased risk for PD is rather limited and based on insufficient epidemiological data. This review critically analyses the evidence that implicates PQ in parkinsonism and discusses the limitations of chemical modelling of PD.


Asunto(s)
Herbicidas/toxicidad , Paraquat/toxicidad , Enfermedad de Parkinson/etiología , Animales , Apoptosis , Modelos Animales de Enfermedad , Humanos , Ratones , Degeneración Nerviosa/etiología , Enfermedad de Parkinson/epidemiología , Factores de Riesgo
10.
Cell Death Differ ; 17(1): 119-33, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19713973

RESUMEN

Cell death requires coordinated intracellular signalling before disassembly of cell architecture by degradative enzymes. Although the death signalling cascades that involve the mitochondria, the ER and the plasma membrane have been extensively characterized, only a handful of studies have examined the functional and structural alterations of the nuclear pore complex (NPC) during neuronal death. Here, we show that during excitotoxic neuronal degeneration calpains redistributed across the nuclear envelope and mediated the degradation of NPC components causing altered permeability of the nuclear membrane. In primary dissociated neurons, simultaneous recording of cytosolic [Ca(2+)] and localization of fluorescent proteins showed that the onset of Ca(2+) overload signalled a progressive increase in the diffusion of small reporter molecules across the nuclear envelope. Later, calpain-mediated changes in nuclear pore permeability allowed accumulation of large proteins in the nucleus. Further, in a model of excitotoxic neuronal degeneration in Caenorhabditis elegans, we found similar nuclear changes and redistribution of fluorescent probes across the nuclear membrane in dying neurons. Our findings strongly suggest that increased leakiness of the nuclear barrier affects nucleocytoplasmic transport, alters the localization of proteins across the nuclear envelope and it is likely to be involved in Ca(2+)-dependent cell death, including ischemic neuronal demise.


Asunto(s)
Apoptosis , Calcio/metabolismo , Proteínas de Complejo Poro Nuclear/metabolismo , Poro Nuclear/fisiología , Animales , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Calpaína/metabolismo , Células Cultivadas , Ácido Glutámico/farmacología , Gliceraldehído 3-Fosfato Deshidrogenasa (NADP+)/metabolismo , Células HeLa , Humanos , Ratas , Receptores Nicotínicos/metabolismo , Transducción de Señal
11.
Radiol Med ; 114(4): 608-25, 2009 Jun.
Artículo en Inglés, Italiano | MEDLINE | ID: mdl-19444588

RESUMEN

PURPOSE: The treatment of pain in bone metastases is currently multidisciplinary. Among the various therapies, local radiotherapy is the gold standard for pain palliation from single metastasis, even though the maximum benefit is obtained between 12 and 20 weeks from initiation. In carefully selected patients, several ablation therapies achieve this objective in 4 weeks. The purpose of this study was to assess the technical success, effectiveness and possible complications of percutaneous ablation therapies in patients with symptomatic bone metastases. MATERIALS AND METHODS: From November 2003 to May 2008, ten ablation treatments were performed in ten patients with acute pain from metastatic bone lesions. Patient selection and choice of the most appropriate ablation treatment was made based on lesion characteristics. Three patients were treated with radiofrequency, one with plasma-mediated radiofrequency, two with plasma-mediated radiofrequency and cementoplasty, three with radiofrequency and cementoplasty and one with microwave. RESULTS: Assessments were based not only on imaging but also on the visual analogue scale (VAS) score for determining pain and on changes in morphine-equivalent doses. In both cases, 3-month follow-up showed a statistically significant reduction of pain. In no case did local complications occur either during or after treatment. Only one patient treated with radiofrequency (1/9, 11%) developed low-grade fever and general malaise during the 6 days following the procedure, compatible with a post-radiofrequency syndrome, which was treated with acetaminophen (paracetamol) only and resolved on day 7. CONCLUSIONS: Percutaneous ablation therapies represent a safe and valuable alternative for treating localised pain from single bone metastasis, providing rapid (4-week) relief of symptoms and a significant reduction in morphine doses. This contributes to improving the quality of life of patients with metastatic disease.


Asunto(s)
Neoplasias Óseas/secundario , Neoplasias Óseas/cirugía , Ablación por Catéter , Adulto , Anciano , Anciano de 80 o más Años , Analgésicos Opioides/uso terapéutico , Neoplasias Óseas/complicaciones , Neoplasias Óseas/tratamiento farmacológico , Relación Dosis-Respuesta a Droga , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Morfina/uso terapéutico , Dolor/tratamiento farmacológico , Dolor/etiología , Calidad de Vida , Estudios Retrospectivos , Resultado del Tratamiento
12.
Radiol Med ; 113(7): 999-1007, 2008 Oct.
Artículo en Inglés, Italiano | MEDLINE | ID: mdl-18795233

RESUMEN

PURPOSE: This study was undertaken to evaluate the efficacy of image-guided percutaneous drainage in treating abdominal and pelvic abscesses. MATERIALS AND METHODS: From August 2001 to August 2006, 95 patients (49 men and 46 women; mean age 61 years, range 25-92) with 107 abscesses underwent image-guided percutaneous drainage. Thirty-one abscesses were retroperitoneal (9 peripancreatic, 17 perirenal, 5 pararenal), 37 intraperitoneal (2 in communication with the small bowel), 8 intrahepatic (2 in communication with the extrahepatic biliary system and 2 with the intrahepatic biliary system), 4 perisplenic and 27 pelvic (4 in communication with the large bowel). Seventy-one of 107 procedures were performed with ultrasonographic (US) guidance and 36/107 with computed tomography (CT) guidance. All procedures were carried out with 8-to 14-Fr pigtail drainage catheters. RESULTS: Immediate technical success was achieved in 107/107 fluid collections. No major complications occurred. In 98/107 abscesses, we obtained progressive shrinkage of the collection (>50%) with consequent clinical success. In 9/107 cases, percutaneous drainage was unable to resolve the fluid collection. There were 12 cases of catheter displacement and six of obstruction. CONCLUSIONS: Percutaneous drainage is feasible and effective in treating abdominal and pelvic abscesses. It may be considered both as a preparatory step for surgery and a valuable alternative to open surgery. Failure of the procedure does not, however, preclude a subsequent surgical operation.


Asunto(s)
Absceso Abdominal/diagnóstico por imagen , Absceso Abdominal/terapia , Absceso/diagnóstico por imagen , Absceso/terapia , Drenaje/métodos , Pelvis , Tomografía Computarizada por Rayos X/métodos , Ultrasonografía Intervencional , Adulto , Anciano , Anciano de 80 o más Años , Drenaje/instrumentación , Estudios de Factibilidad , Femenino , Humanos , Absceso Hepático/diagnóstico por imagen , Absceso Hepático/terapia , Masculino , Persona de Mediana Edad , Pelvis/diagnóstico por imagen , Resultado del Tratamiento
13.
Cell Death Differ ; 15(5): 820-30, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18309326

RESUMEN

Primary chronic lymphocytic leukemia (CLL) cells are exquisitely sensitive to ABT-737, a small molecule BCL2-antagonist, which induces many of the classical biochemical and ultrastructural features of apoptosis, including BAX/BAK oligomerization, cytochrome c release, caspase activation and chromatin condensation. Surprisingly, ABT-737 also induces mitochondrial inner membrane permeabilization (MIMP) resulting in mitochondrial matrix swelling and rupture of the outer mitochondrial membrane (OMM), so permitting the rapid efflux of cytochrome c from mitochondrial cristae and facilitating rapid caspase activation and apoptosis. BAX and BAK appear to be involved in the OMM discontinuities as they localize to the OMM break points. Notably, ABT-737 induced mitochondrial matrix swelling and OMM discontinuities in other primary B-cell malignancies, including mantle cell, follicular and marginal zone lymphoma cells but not in several cell lines studied. Thus, we describe a new paradigm of apoptosis in primary B-cell malignancies, whereby targeting of BCL2 results in all the classical features of apoptosis together with OMM rupture independent of caspase activation. This mechanism may be far more prevalent than hitherto recognized due to the failure of most methods, used to measure apoptosis, to recognize such a mechanism.


Asunto(s)
Apoptosis/efectos de los fármacos , Compuestos de Bifenilo/farmacología , Leucemia Linfocítica Crónica de Células B/metabolismo , Membranas Mitocondriales/efectos de los fármacos , Nitrofenoles/farmacología , Sulfonamidas/farmacología , Adulto , Clorometilcetonas de Aminoácidos/metabolismo , Linfocitos B/efectos de los fármacos , Linfocitos B/metabolismo , Linfocitos B/patología , Línea Celular Tumoral , Inhibidores de Cisteína Proteinasa/metabolismo , Relación Dosis-Respuesta a Droga , Humanos , Leucemia Linfocítica Crónica de Células B/patología , Membranas Mitocondriales/ultraestructura , Piperazinas/farmacología , Proteínas Proto-Oncogénicas c-bcl-2/antagonistas & inhibidores , Proteína Destructora del Antagonista Homólogo bcl-2/metabolismo , Proteína X Asociada a bcl-2/metabolismo
14.
Cell Death Differ ; 15(2): 283-98, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18007665

RESUMEN

Disruption of synaptic integrity, loss of connectivity and axodendritic degeneration are early and essential components of neurodegeneration. Although neuronal cell death mechanisms have been thoroughly investigated, less is known about the signals involved in axodendritic damage and the processes involved in regeneration. Here we conducted a genome-wide RNA interference-based forward genetic screen, using small interfering RNA targeting all human kinases, and identified clusters of kinases families essential for growth cone collapse, neurite retraction and neurite outgrowth. Of 59 kinases identified as positive regulators of neurite outgrowth, almost 50% were in the tyrosine kinase/tyrosine kinase-like (TK/TKL) receptor subgroups, underlining the importance of extracellular ligands in this process. Neurite outgrowth was inhibited by 66 other kinases, none of which were TK/TKL members, whereas 79 kinases inhibited lysophosphatidic acid-induced neurite retraction. Twenty kinases were involved in both inhibitory processes suggesting shared mechanisms. Within this group of 20 kinases, some (ULK1, PDK1, MAP4K4) have been implicated previously in axonal events, but others (MAST2, FASTK, CKM and DGUOK) have not. For a subset of kinases, the effect on neurite outgrowth was validated in rat primary cerebellar cultures. The ability to affect regeneration was further tested in a model of axodendritic lesion using primary rat midbrain cultures. Finally, we demonstrated that haploinsufficiency of two members of the AGC kinase subgroup, ROCK1 and PKN1, was able to suppress retinal degeneration in Drosophila model of class III Autosomal Dominant Retinitis Pigmentosa.


Asunto(s)
Conos de Crecimiento/fisiología , Neuritas/fisiología , Proteínas Quinasas/metabolismo , Interferencia de ARN , Animales , Drosophila , Humanos , Neuritas/metabolismo , Ratas , Ratas Wistar , Retinitis Pigmentosa/genética , Retinitis Pigmentosa/metabolismo
17.
Ann N Y Acad Sci ; 1099: 451-5, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17446485

RESUMEN

Neurodegenerative conditions commonly involve loss of neuronal connectivity, synaptic dysfunction with excessive pruning, and ionic imbalances. These often serve as a prelude to cell death either through the activation of apoptotic or necrotic death routines or excess autophagy. In many instances, a local or generalized Ca2+ deregulation is involved in signaling or executing cell death. We have recently shown that in brain ischemia, and during excitotoxicity triggered by excess glutamate, the irreversible Ca2+ deregulation leading to necrosis is due to calpain-mediated modulation of the plasma membrane Na+/Ca2+ exchanger (NCX). Here we show that the NCX can also be cleaved by caspases in neurons undergoing apoptosis, which suggests that cleavage of the main Ca2+ extrusion pathway is a lethal event in multiple forms of cell death.


Asunto(s)
Apoptosis , Neuronas/metabolismo , Péptido Hidrolasas/metabolismo , Intercambiador de Sodio-Calcio/metabolismo , Línea Celular Tumoral , Membrana Celular/metabolismo , Medio de Cultivo Libre de Suero , Humanos , Hidrólisis , Neuronas/citología
20.
Cell Death Differ ; 9(8): 818-31, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12107825

RESUMEN

Neuronal death, which follows ischemic injury or is triggered by excitotoxins, can occur by both apoptosis and necrosis. Caspases, which are not directly required for necrotic cell death, are central mediators of the apoptotic program. Here we demonstrate that caspases cleave and inactivate the plasma membrane Ca(2+) pump (PMCA) in neurons and non-neuronal cells undergoing apoptosis. PMCA cleavage impairs intracellular Ca(2+) handling, which results in Ca(2+) overload. Expression of non-cleavable PMCA mutants prevents the disturbance in Ca(2+) handling, slows down the kinetics of apoptosis, and markedly delays secondary cell lysis (necrosis). These findings suggest that caspase-mediated cleavage and inactivation of PMCAs can lead to necrosis, an event that is reduced by caspase inhibitors in brain ischemia.


Asunto(s)
Apoptosis/fisiología , ATPasas Transportadoras de Calcio/metabolismo , Caspasas/metabolismo , Membrana Celular/enzimología , Hipoxia-Isquemia Encefálica/enzimología , Necrosis , Neuronas/enzimología , Animales , Animales Recién Nacidos , Apoptosis/efectos de los fármacos , Sitios de Unión/efectos de los fármacos , Sitios de Unión/fisiología , Células CHO , Calcio/metabolismo , Señalización del Calcio/efectos de los fármacos , Señalización del Calcio/fisiología , ATPasas Transportadoras de Calcio/efectos de los fármacos , Caspasa 3 , Caspasas/efectos de los fármacos , Caspasas/genética , Proteínas de Transporte de Catión , Membrana Celular/efectos de los fármacos , Células Clonales/citología , Células Clonales/efectos de los fármacos , Células Clonales/metabolismo , Colorantes , Cricetinae , Hipoxia-Isquemia Encefálica/patología , Hipoxia-Isquemia Encefálica/fisiopatología , Inmunohistoquímica , Líquido Intracelular/metabolismo , Ratones , Mutación/efectos de los fármacos , Mutación/genética , Neuronas/efectos de los fármacos , Neuronas/patología , Neurotoxinas/farmacología , ATPasas Transportadoras de Calcio de la Membrana Plasmática , Ratas
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