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1.
J Intern Med ; 281(1): 7-24, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27251308

RESUMEN

In this review, we present findings that support autocrine cell protection by C-peptide in the context of clinical studies of type 1 diabetes (T1D), which universally measure C-peptide serum levels as a surrogate for ß cell functional mass. Over the last decade, evidence has accumulated that supports models in which C-peptide, cosecreted with insulin by pancreatic ß cells, acts on peripheral targets including the vascular endothelium to reduce oxidative stress and apoptosis subsequent to exposure to diabetic insults. In parallel, as assays have become more sensitive, C-peptide has been detected in the circulation of most subjects with T1D where higher C-peptide levels are associated with fewer and slower development of diabetic microvascular complications, consistent with antioxidant protection by C-peptide. Clinical trials investigating C-peptide-replacement therapy effects have demonstrated amelioration of T1D nephropathy and neuropathy. Recently, the antioxidant action of C-peptide was extended to the ß cells secreting it, that is an autocrine mechanism. Autocrine protection has major implications for the treatment of diabetes because the more C-peptide secreted, the more protection provided to the same ß cells resulting in a slower decay in ß cell functional mass over the time course of disease. Why ß cells evolved to cosecrete an antioxidant C-peptide hormone together with the glycaemia-lowering insulin hormone is explored in the context of proposed evolutionary advantages of physiologically transient oxidative stress and insulin resistance as an adaptation for survival through times of fuel scarcity. The importance of recognizing autocrine C-peptide protection of functional ß cell mass in observational clinical studies, and its therapeutic implications in interventional C-peptide-replacement studies, will be discussed.


Asunto(s)
Péptido C/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Células Secretoras de Insulina/metabolismo , Animales , Péptido C/sangre , Modelos Animales de Enfermedad , Células Endoteliales/metabolismo , Humanos , Resistencia a la Insulina , Especies Reactivas de Oxígeno
2.
Eur J Neurol ; 22(10): 1337-54, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26255640

RESUMEN

In recent years, evidence has emerged for a bidirectional relationship between sleep and neurological and psychiatric disorders. First, sleep-wake disorders (SWDs) are very common and may be the first/main manifestation of underlying neurological and psychiatric disorders. Secondly, SWDs may represent an independent risk factor for neuropsychiatric morbidities. Thirdly, sleep-wake function (SWF) may influence the course and outcome of neurological and psychiatric disorders. This review summarizes the most important research and clinical findings in the fields of neuropsychiatric sleep and circadian research and medicine, and discusses the promise they bear for the next decade. The findings herein summarize discussions conducted in a workshop with 26 European experts in these fields, and formulate specific future priorities for clinical practice and translational research. More generally, the conclusion emerging from this workshop is the recognition of a tremendous opportunity offered by our knowledge of SWF and SWDs that has unfortunately not yet entered as an important key factor in clinical practice, particularly in Europe. Strengthening pre-graduate and postgraduate teaching, creating academic multidisciplinary sleep-wake centres and simplifying diagnostic approaches of SWDs coupled with targeted treatment strategies yield enormous clinical benefits for these diseases.


Asunto(s)
Investigación Biomédica/tendencias , Neurología/tendencias , Psiquiatría/tendencias , Trastornos del Sueño-Vigilia/fisiopatología , Sueño/fisiología , Humanos
3.
Arch Ital Biol ; 152(2-3): 118-28, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25828684

RESUMEN

Rapid eye movement sleep behavior disorder (RBD) is a parasomnia characterized by the loss of muscle atonia during paradoxical (REM) sleep (PS). Conversely, cataplexy, one of the key symptoms of narcolepsy, is a striking sudden episode of muscle weakness triggered by emotions during wakefulness, and comparable to REM sleep atonia. The neuronal dysfunctions responsible for RBD and cataplexy are not known. In the present review, we present the most recent results on the neuronal network responsible for PS. Based on these results, we propose an updated integrated model of the mechanisms responsible for PS and explore different hypotheses explaining RBD and cataplexy. We propose that RBD is due to a specific degeneration of a subpopulation of PS-on glutamatergic neurons specifically responsible of muscle atonia, localized in the caudal pontine sublaterodorsal tegmental nucleus (SLD). Another possibility is the occurrence in RBD patients of a specific lesion of the glycinergic/GABAergic premotor-neurons localized in the medullary ventral gigantocellular reticular nucleus. Conversely, cataplexy in narcoleptics would be due to the activation during waking of the caudal PS-on SLD neurons responsible for muscle atonia. A direct or indirect pathway activated during positive emotion from the central amygdala to the SLD PS-on neurons would induce such activation. In normal conditions, the activation of SLD neurons would be blocked by the simultaneous excitation by the hypocretins of the PS-off GABAergic neurons localized in the ventrolateral periaqueductal gray and the adjacent deep mesencephalic reticular nucleus gating the activation of the PS-on SLD neurons.


Asunto(s)
Encéfalo/metabolismo , Narcolepsia/fisiopatología , Trastorno de la Conducta del Sueño REM/fisiopatología , Animales , Encéfalo/fisiología , Modelos Animales de Enfermedad , Humanos , Narcolepsia/etiología , Narcolepsia/metabolismo , Neurotransmisores/metabolismo , Trastorno de la Conducta del Sueño REM/etiología , Trastorno de la Conducta del Sueño REM/metabolismo
4.
Sleep Med ; 14(8): 795-806, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23886593

RESUMEN

OBJECTIVES: We aimed to provide a consensus statement by the International Rapid Eye Movement Sleep Behavior Disorder Study Group (IRBD-SG) on devising controlled active treatment studies in rapid eye movement sleep behavior disorder (RBD) and devising studies of neuroprotection against Parkinson disease (PD) and related neurodegeneration in RBD. METHODS: The consensus statement was generated during the fourth IRBD-SG symposium in Marburg, Germany in 2011. The IRBD-SG identified essential methodologic components for a randomized trial in RBD, including potential screening and diagnostic criteria, inclusion and exclusion criteria, primary and secondary outcomes for symptomatic therapy trials (particularly for melatonin and clonazepam), and potential primary and secondary outcomes for eventual trials with disease-modifying and neuroprotective agents. The latter trials are considered urgent, given the high conversion rate from idiopathic RBD (iRBD) to Parkinsonian disorders (i.e., PD, dementia with Lewy bodies [DLB], multiple system atrophy [MSA]). RESULTS: Six inclusion criteria were identified for symptomatic therapy and neuroprotective trials: (1) diagnosis of RBD needs to satisfy the International Classification of Sleep Disorders, second edition, (ICSD-2) criteria; (2) minimum frequency of RBD episodes should preferably be ⩾2 times weekly to allow for assessment of change; (3) if the PD-RBD target population is included, it should be in the early stages of PD defined as Hoehn and Yahr stages 1-3 in Off (untreated); (4) iRBD patients with soft neurologic dysfunction and with operational criteria established by the consensus of study investigators; (5) patients with mild cognitive impairment (MCI); and (6) optimally treated comorbid OSA. Twenty-four exclusion criteria were identified. The primary outcome measure for RBD treatment trials was determined to be the Clinical Global Impression (CGI) efficacy index, consisting of a four-point scale with a four-point side-effect scale. Assessment of video-polysomnographic (vPSG) changes holds promise but is costly and needs further elaboration. Secondary outcome measures include sleep diaries; sleepiness scales; PD sleep scale 2 (PDSS-2); serial motor examinations; cognitive indices; mood and anxiety indices; assessment of frequency of falls, gait impairment, and apathy; fatigue severity scale; and actigraphy and customized bed alarm systems. Consensus also was established for evaluating the clinical and vPSG aspects of RBD. End points for neuroprotective trials in RBD, taking lessons from research in PD, should be focused on the ultimate goal of determining the performance of disease-modifying agents. To date no compound with convincing evidence of disease-modifying or neuroprotective efficacy has been identified in PD. Nevertheless, iRBD patients are considered ideal candidates for neuroprotective studies. CONCLUSIONS: The IRBD-SG provides an important platform for developing multinational collaborative studies on RBD such as on environmental risk factors for iRBD, as recently reported in a peer-reviewed journal article, and on controlled active treatment studies for symptomatic and neuroprotective therapy that emerged during the 2011 consensus conference in Marburg, Germany, as described in our report.


Asunto(s)
Fármacos Neuroprotectores/uso terapéutico , Enfermedad de Parkinson/prevención & control , Trastorno de la Conducta del Sueño REM/diagnóstico , Trastorno de la Conducta del Sueño REM/tratamiento farmacológico , Ensayos Clínicos como Asunto/métodos , Ensayos Clínicos como Asunto/normas , Clonazepam/uso terapéutico , Consenso , Moduladores del GABA/uso terapéutico , Humanos , Melatonina/uso terapéutico , Enfermedad de Parkinson/epidemiología , Trastorno de la Conducta del Sueño REM/epidemiología , Factores de Riesgo
5.
Diabetologia ; 54(10): 2702-12, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21773684

RESUMEN

AIMS/HYPOTHESIS: Reactive oxygen species (ROS) generated during hyperglycaemia are implicated in the development of diabetic vascular complications. High glucose increases oxidative stress in endothelial cells and induces apoptosis. A major source of ROS in endothelial cells exposed to glucose is the NAD(P)H oxidase enzyme. Several studies demonstrated that C-peptide, the product of proinsulin cleavage within the pancreatic beta cells, displays anti-inflammatory effects in certain models of vascular dysfunction. However, the molecular mechanism underlying this effect is unclear. We hypothesised that C-peptide reduces glucose-induced ROS generation by decreasing NAD(P)H oxidase activation and prevents apoptosis METHODS: Human aortic endothelial cells (HAEC) were exposed to 25 mmol/l glucose in the presence or absence of C-peptide and tested for protein quantity and activity of caspase-3 and other apoptosis markers by ELISA, TUNEL and immunoblotting. Intracellular ROS were measured by flow cytometry using the ROS sensitive dye chloromethyl-2',7'-dichlorodihydrofluorescein diacetate (CM-H(2)-DCDFA). NAD(P)H oxidase activation was assayed by lucigenin. Membrane and cytoplasmic levels of the NAD(P)H subunit ras-related C3 botulinum toxin substrate 1 (rho family, small GTP binding protein Rac1) (RAC-1) and its GTPase activity were studied by immunoblotting and ELISA. RAC-1 (also known as RAC1) gene expression was investigated by quantitative real-time PCR. RESULTS: C-peptide significantly decreased caspase-3 levels and activity and upregulated production of the anti-apoptotic factor B cell CLL/lymphoma 2 (BCL-2). Glucose-induced ROS production was quenched by C-peptide and this was associated with a decreased NAD(P)H oxidase activity and reduced RAC-1 membrane production and GTPase activity. CONCLUSIONS/INTERPRETATION: In glucose-exposed endothelial cells, C-peptide acts as an endogenous antioxidant molecule by reducing RAC-1 translocation to membrane and NAD(P)H oxidase activation. By preventing oxidative stress, C-peptide protects endothelial cells from glucose-induced apoptosis.


Asunto(s)
Péptido C/farmacología , Células Endoteliales/metabolismo , Glucosa/farmacología , NADPH Oxidasas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Aorta/citología , Apoptosis/efectos de los fármacos , Células Cultivadas , Células Endoteliales/efectos de los fármacos , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Humanos , Immunoblotting , Etiquetado Corte-Fin in Situ , Reacción en Cadena en Tiempo Real de la Polimerasa , Proteína de Unión al GTP rac1/genética
6.
Diabetologia ; 52(10): 2218-28, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19662378

RESUMEN

AIMS/HYPOTHESIS: There is increasing evidence that C-peptide exerts intracellular effects in a variety of cells and could be beneficial in patients with type 1 diabetes. Exactly how C-peptide achieves these effects, however, is unknown. Recent reports showed that C-peptide internalised in the cytoplasm of HEK-293 and Swiss 3T3 cells, where it was not degraded for at least 1 h after uptake. In this study, we investigated the hypothesis that C-peptide is internalised via an endocytic pathway and traffics to classic endocytic organelles, such as endosomes and lysosomes. METHODS: We studied the internalisation of C-peptide in vascular endothelial and smooth muscle cells, two relevant targets of C-peptide activity, by using Alexa Fluor-labelled C-peptide probes in living cells and immunohistochemistry employing confocal laser-scanning microscopy. To examine trafficking to subcellular compartments, we used fluorescent constructs tagged to RAB5A, member RAS oncogene family (RAB5A) to identify early endosomes, or to lysosomal-associated membrane protein 1 (LAMP1) to identify lysosomes. RESULTS: C-peptide internalised in the cytoplasm of cells within punctate structures identified as early endosomes. Internalisation was clearly detectable after 10 min of incubation and was blocked at 4 degrees C as well as with excess of unlabelled C-peptide. A minor fraction of vesicles, which increased with culture time, co-localised with lysosomes. Uptake of C-peptide was reduced by monodansylcadaverine, a pharmacological compound that blocks clathrin-mediated endocytosis, and by nocodazole, which disrupts microtubule assembly. CONCLUSIONS/INTERPRETATION: C-peptide internalises in the cytoplasm of cells by endocytosis, as demonstrated by its localisation in early endosomes. Endosomes might represent a signalling station, through which C-peptide might achieve its cellular effects.


Asunto(s)
Péptido C/metabolismo , Endosomas/metabolismo , Células Endoteliales/metabolismo , Músculo Liso Vascular/citología , Miocitos del Músculo Liso/metabolismo , Anisoles/farmacología , Línea Celular , Cicloheptanos/farmacología , Citocalasina D/farmacología , Endocitosis/efectos de los fármacos , Endosomas/efectos de los fármacos , Células Endoteliales/efectos de los fármacos , Filipina/farmacología , Humanos , Inmunohistoquímica , Microscopía Confocal , Miocitos del Músculo Liso/efectos de los fármacos , Nocodazol/farmacología , Temperatura
7.
Eur J Neurosci ; 29(9): 1741-53, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19473229

RESUMEN

Since the discovery of rapid eye movement (REM) sleep (also known as paradoxical sleep; PS), it is accepted that sleep is an active process. PS is characterized by EEG rhythmic activity resembling that of waking with a disappearance of muscle tone and the occurrence of REMs, in contrast to slow-wave sleep (SWS, also known as non-REM sleep) identified by the presence of delta waves. Here, we review the most recent data on the mechanisms responsible for the genesis of SWS and PS. Based on these data, we propose an updated integrated model of the mechanisms responsible for the sleep-wake cycle. This model introduces for the first time the notion that the entrance and exit of PS are induced by different mechanisms. We hypothesize that the entrance from SWS to PS is due to the intrinsic activation of PS-active GABAergic neurons localized in the posterior hypothalamus (co-containing melanin-concentrating hormone), ventrolateral periaqueductal gray and the dorsal paragigantocellular reticular nucleus. In contrast, the exit from PS is induced by the inhibition of these neurons by a PS-gating system composed of GABAergic neurons localized in the ventrolateral periaqueductal gray and just ventral to it, and waking systems such as the pontine and medullary noradrenergic neurons and the hypothalamic hypocretin neurons. Finally, we review human neurological disorders of the network responsible for sleep and propose hypotheses on the mechanisms responsible for REM behavior disorder and narcolepsy.


Asunto(s)
Encéfalo/fisiología , Neuronas/fisiología , Sueño/fisiología , Acetilcolina/metabolismo , Animales , Monoaminas Biogénicas/metabolismo , Encéfalo/fisiopatología , Ácido Glutámico/metabolismo , Humanos , Hormonas Hipotalámicas/metabolismo , Melaninas/metabolismo , Modelos Neurológicos , Narcolepsia/fisiopatología , Vías Nerviosas/fisiología , Vías Nerviosas/fisiopatología , Hormonas Hipofisarias/metabolismo , Trastorno de la Conducta del Sueño REM/fisiopatología , Vigilia/fisiología , Ácido gamma-Aminobutírico/metabolismo
8.
Neuroscience ; 155(1): 174-81, 2008 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-18573315

RESUMEN

Overlapped in the tuberal hypothalamic area (THA), melanin-concentrating hormone (MCH) and hypocretin (Hcrt) neurons contribute to the integrated regulation of food intake, energy regulation and sleep. Recently, physiological role in appetite suppression has been defined for a novel hypothalamic molecule, nesfatin-1. Acute i.c.v. infusion of nesfatin-1 (nesf-1) promotes anorexia whereas chronic treatment reduces body weight in rats. This satiety molecule is expressed in neurons from areas prominently involved in appetite regulation including THA. We therefore sought functionally relevant to determine whether nesf-1 might be a reliable signaling marker for a new cell contingent within THA, in addition to MCH and Hcrt neurons. Thus, we completed a detailed topographical mapping of neurons immunostained for nesf-1 (nesf-1+) together with cell quantification in each discrete nucleus from THA in the rat. We further combined the immunodetection of nesf-1 with that of MCH or Hcrt to assess possible co-expression. More than three quarters of the nesf-1+ neurons were encountered in nuclei from the lateral half of THA. By double immunofluorescent staining, we showed that all neurons immunoreactive for melanin concentrating hormone (MCH+) neurons depicted nesf-1 immunoreactivity and approximately 80% of the nesf-1+ neurons were labeled for MCH. Maximal co-expression rates were observed in the lateral THA containing approximately 86% of the double-labeled neurons plotted in THA. The present data suggest that nesf-1 co-expressed in MCH neurons may play a complex role not only in food intake regulation but also in other essential integrative brain functions involving MCH signaling, ranging from autonomic regulation, stress, mood, cognition to sleep.


Asunto(s)
Hipotálamo/citología , Melaninas/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Neuronas/metabolismo , Animales , Mapeo Encefálico , Proteínas de Unión al Calcio , Recuento de Células , Proteínas de Unión al ADN , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Masculino , Neuropéptidos/metabolismo , Nucleobindinas , Orexinas , Ratas , Ratas Sprague-Dawley
9.
Diabetologia ; 51(8): 1534-43, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18493738

RESUMEN

AIMS/HYPOTHESIS: Endothelial dysfunction in diabetes is predominantly caused by hyperglycaemia leading to vascular complications through overproduction of oxidative stress and activation of the transcription factor nuclear factor-kappaB (NF-kappaB). Many studies have suggested that decreased circulating levels of C-peptide may play a role in diabetic vascular dysfunction. To date, the possible effects of C-peptide on endothelial cells and intracellular signalling pathways are largely unknown. We therefore investigated the effect of C-peptide on several biochemical markers of endothelial dysfunction in vitro. To gain insights into potential intracellular signalling pathways affected by C-peptide, we tested NF-kappaB activation, since it is known that inflammation, secondary to oxidative stress, is a key component of vascular complications and NF-kappaB is a redox-dependent transcription factor. METHODS: Human aortic endothelial cells (HAEC) were exposed to 25 mmol/l glucose in the presence of C-peptide (0.5 nmol/l) for 24 h and tested for expression of the gene encoding vascular cell adhesion molecule-1 (VCAM-1) by RT-PCR and flow cytometry. Secretion of IL-8 and monocyte chemoattractant protein-1 (MCP-1) was measured by ELISA. NF-kappaB activation was analysed by immunoblotting and ELISA. RESULTS: Physiological concentrations of C-peptide affect high glucose-induced endothelial dysfunction by: (1) decreasing VCAM-1 expression and U-937 cell adherence to HAEC; (2) reducing secretion of IL-8 and MCP-1; and (3) suppressing NF-kappaB activation. CONCLUSIONS/INTERPRETATION: During hyperglycaemia, C-peptide directly affects VCAM-1 expression and both MCP-1 and IL-8 HAEC secretion by reducing NF-kappaB activation. These effects suggest a physiological anti-inflammatory (and potentially anti-atherogenic) activity of C-peptide on endothelial cells.


Asunto(s)
Péptido C/farmacología , Endotelio Vascular/fisiopatología , Glucosa/farmacología , FN-kappa B/fisiología , Aorta , Técnicas de Cultivo de Célula , Quimiocina CCL2/metabolismo , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/metabolismo , Glucosa/antagonistas & inhibidores , Humanos , Interleucina-8/metabolismo , Estrés Oxidativo/efectos de los fármacos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Molécula 1 de Adhesión Celular Vascular/efectos de los fármacos , Molécula 1 de Adhesión Celular Vascular/genética
10.
Neuroscience ; 152(3): 849-57, 2008 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-18308473

RESUMEN

It is well known that noradrenergic locus coeruleus neurons decrease their activity during slow wave sleep and are quiescent during paradoxical sleep. It was recently proposed that their inactivation during paradoxical sleep is due to a tonic GABAergic inhibition arising from neurons located into the dorsal paragigantocellular reticular nucleus (DPGi). However, the discharge profile of DPGi neurons across the sleep-waking cycle as well as their connections with brain areas involved in paradoxical sleep regulation remain to be described. Here we show, for the first time in the unanesthetized rat that the DPGi contained a subtype of neurons with a tonic and sustained firing activation specifically during paradoxical sleep (PS-on neurons). Noteworthy, their firing rate increase anticipated for few seconds the beginning of the paradoxical sleep bout. By using anterograde tract-tracing, we further showed that the DPGi, in addition to locus coeruleus, directly projected to other areas containing wake-promoting neurons such as the serotonergic neurons of the dorsal raphe nucleus and hypocretinergic neurons of the posterior hypothalamus. Finally, the DPGi sent efferents to the ventrolateral part of the periaqueductal gray matter known to contain paradoxical sleep-suppressing neurons. Taken together, our original results suggest that the PS-on neurons of the DPGi may have their major role in simultaneous inhibitory control over the wake-promoting neurons and the permissive ventrolateral part of the periaqueductal gray matter as a means of influencing vigilance states and especially PS generation.


Asunto(s)
Bulbo Raquídeo/citología , Bulbo Raquídeo/fisiología , Formación Reticular/citología , Formación Reticular/fisiología , Sueño REM/fisiología , Vigilia/fisiología , Potenciales de Acción/fisiología , Animales , Transporte Axonal/fisiología , Axones/fisiología , Axones/ultraestructura , Tronco Encefálico/citología , Tronco Encefálico/fisiología , Toxina del Cólera , Electrofisiología , Hipotálamo/citología , Hipotálamo/fisiología , Masculino , Inhibición Neural/fisiología , Vías Nerviosas/citología , Vías Nerviosas/fisiología , Neuronas/citología , Neuronas/fisiología , Fitohemaglutininas , Ratas , Ratas Sprague-Dawley , Coloración y Etiquetado , Estilbamidinas
11.
Neuroscience ; 142(1): 37-47, 2006 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-16891059

RESUMEN

It is well established that, during rapid eye movement (REM) sleep, somatic motoneurons are subjected to a barrage of inhibitory synaptic potentials that are mediated by glycine. However, the source of this inhibition, which is crucial for the maintenance and preservation of REM sleep, has not been identified. Consequently, the present study was undertaken to determine in cats the location of the glycinergic neurons, that are activated during active sleep, and are responsible for the postsynaptic inhibition of motoneurons that occurs during this state. For this purpose, a pharmacologically-induced state of active sleep (AS-carbachol) was employed. Antibodies against glycine-conjugated proteins were used to identify glycinergic neurons and immunocytochemical techniques to label the Fos protein were employed to identify activated neurons. Two distinct populations of glycinergic neurons that expressed c-fos were distinguished. One population was situated within the nucleus reticularis gigantocellularis (NRGc) and nucleus magnocellularis (Mc) in the rostro-ventral medulla; this group of neurons extended caudally to the ventral portion of the nucleus paramedianus reticularis (nPR). Forty percent of the glycinergic neurons in the NRGc and Mc and 25% in the nPR expressed c-fos during AS-carbachol. A second population was located in the caudal medulla adjacent to the nucleus ambiguus (nAmb), wherein 40% of the glycinergic cells expressed c-fos during AS-carbachol. Neither population of glycinergic cells expressed c-fos during quiet wakefulness or quiet (non-rapid eye movement) sleep. We suggest that the population of glycinergic neurons in the NRGc, Mc, and nPR participates in the inhibition of somatic brainstem motoneurons during active sleep. These neurons may also be responsible for the inhibition of sensory and other processes during this state. It is likely that the group of glycinergic neurons adjacent to the nucleus ambiguus (nAmb) is responsible for the active sleep-selective inhibition of motoneurons that innervate the muscles of the larynx and pharynx.


Asunto(s)
Tronco Encefálico/citología , Glicina/metabolismo , Neuronas/metabolismo , Sueño REM/fisiología , Analgésicos no Narcóticos/farmacología , Animales , Carbacol/farmacología , Gatos , Femenino , Inmunohistoquímica/métodos , Masculino , Neuronas/clasificación , Proteínas Proto-Oncogénicas c-fyn/metabolismo , Sueño REM/efectos de los fármacos
12.
Neuroscience ; 134(4): 1377-90, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16039802

RESUMEN

Recent research has shown that neurons in the ventrolateral preoptic nucleus are crucial for sleep by inhibiting wake-promoting systems, but the process that triggers their activation at sleep onset remains to be established. Since evidence indicates that sleep induced by adenosine, an endogenous sleep-promoting substance, requires activation of brain A(2A) receptors, we examined the hypothesis that adenosine could activate ventrolateral preoptic nucleus sleep neurons via A(2A) adenosine receptors in rat brain slices. Following on from our initial in vitro identification of these neurons as uniformly inhibited by noradrenaline and acetylcholine arousal transmitters, we established that the ventrolateral preoptic nucleus comprises two intermingled subtypes of sleep neurons, differing in their firing responses to serotonin, inducing either an inhibition (Type-1 cells) or an excitation (Type-2 cells). Since both cell types contained galanin and expressed glutamic acid decarboxylase-65/67 mRNAs, they potentially correspond to the sleep promoting neurons inhibiting arousal systems. Our pharmacological investigations using A(1) and A(2A) adenosine receptors agonists and antagonists further revealed that only Type-2 neurons were excited by adenosine via a postsynaptic activation of A(2A) adenosine receptors. Hence, the present study is the first demonstration of a direct activation of the sleep neurons by adenosine. Our results further support the cellular and functional heterogeneity of the sleep neurons, which could enable their differential contribution to the regulation of sleep. Adenosine and serotonin progressively accumulate during arousal. We propose that Type-2 neurons, which respond to these homeostatic signals by increasing their firing are involved in sleep induction. In contrast, Type-1 neurons would likely play a role in the consolidation of sleep.


Asunto(s)
Adenosina/metabolismo , Neuronas/citología , Área Preóptica/citología , Receptor de Adenosina A2A/metabolismo , Sueño/fisiología , Agonistas del Receptor de Adenosina A2 , Antagonistas del Receptor de Adenosina A2 , Animales , Neuronas/metabolismo , Técnicas de Cultivo de Órganos , Técnicas de Placa-Clamp , Área Preóptica/fisiología , Ratas , Ratas Sprague-Dawley , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Serotonina/metabolismo
13.
G Ital Med Lav Ergon ; 27(4): 412-6, 2005.
Artículo en Italiano | MEDLINE | ID: mdl-16512337

RESUMEN

The increased prevalence of neoplastic diseases observed over the last years has resulted for in more frequent operations of preparation and administration of antiblastic drugs performed by the medical personnel. In this study, we examined a group of subjects involved in the preparation of ACNU, Methotrexate, Novantrone, Vincristine, Cyclophosphamide, Carboplatinum, Mythoxantrone, in order to elucidate whether headache may represent an early symptom of exposure to these products. At the same time, we measured the degree of pollution in the air surrounding the vertical laminar flow aspiration cabinet used for drug preparation. The 66.6% of the 12 subjects studied, 9 females and 3 males, complained of headache. However, the environmental detection using high performance liquid chromatography coupled with triple quadrupole mass spectrometry (HPLC/MS/MS) gave negative results with respect to a possible environmental damage. These findings suggest that headache is the onset symptom of the toxic effect of antiblastic chemiotherapics in the medical personnel involved in drug preparation and administration.


Asunto(s)
Contaminantes Ocupacionales del Aire/análisis , Antineoplásicos/efectos adversos , Cefalea/inducido químicamente , Personal de Salud , Enfermedades Profesionales , Exposición Profesional/efectos adversos , Adulto , Antineoplásicos/administración & dosificación , Cromatografía Líquida de Alta Presión , Composición de Medicamentos , Femenino , Cefalea/diagnóstico , Cefalea/etiología , Humanos , Masculino , Espectrometría de Masas , Persona de Mediana Edad , Enfermedades Profesionales/inducido químicamente , Enfermedades Profesionales/diagnóstico , Factores de Riesgo , Factores de Tiempo
14.
Arch Ital Biol ; 142(4): 397-411, 2004 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15493544

RESUMEN

This paper is dedicated to our mentor, Michel Jouvet who inspired our career and transmitted to us his passion for the study of the mechanisms responsible for paradoxical sleep genesis and also that of its still mysterious functions. We expose in the following the progresses in the knowledge in this field brought during 40 years by Michel Jouvet and his team and more recently by the members of a new CNRS laboratory in which we aim to pursue in the path opened by Michel Jouvet.


Asunto(s)
Tronco Encefálico/fisiología , Vías Nerviosas/fisiología , Neurotransmisores/fisiología , Sueño REM/fisiología , Animales , Tronco Encefálico/anatomía & histología , Humanos , Modelos Neurológicos , Inhibición Neural/fisiología , Vías Nerviosas/anatomía & histología , Ratas , Formación Reticular/anatomía & histología , Formación Reticular/fisiología
16.
Pharmacol Biochem Behav ; 73(3): 557-63, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12151030

RESUMEN

A number of studies in humans and various other species have shown that chronic treatment with antidepressants, such as tricyclics or selective serotonin reuptake inhibitors (SSRIs), induces a decrease or suppression of rapid eye movement (REM) sleep. The effect of a new selective serotonin and noradrenaline reuptake inhibiting (SNRI) antidepressant, milnacipran, on REM sleep has been investigated and compared with that of the SSRI, paroxetine, and the tricyclic, imipramine. Rats injected with vehicle or milnacipran twice a day showed, over 24 h, a similar amount of REM sleep, number and duration of REM sleep episodes to control rats. In contrast, rats treated acutely with imipramine or paroxetine showed a statistically significant decrease in the total quantity of REM sleep. The number of REM sleep episodes was decreased while their duration was increased. A more detailed analysis showed further that the quantity of REM sleep was decreased for the first 4 h following the 9 a.m. injection but not the 7 p.m. injection for milnacipran, during the first 6 h for paroxetine and for the entire light-dark period for imipramine. For all drugs, the quantities of slow-wave sleep and waking over 24 h were not significantly different from control conditions and no rebound of REM sleep occurred during the day following withdrawal. Power spectrum analysis revealed no global changes in the different electroencephalogram (EEG) waves (delta, theta, gamma) between the control condition and the different treatments during waking, slow-wave sleep or REM sleep. Taken together our results indicate that the SNRI, milnacipran, at therapeutic doses, induces only minor disturbances of REM sleep compared with a SSRI and tricyclic antidepressant used. Possible mechanisms responsible for the difference of action on REM sleep of milnacipran are discussed.


Asunto(s)
Inhibidores de Captación Adrenérgica/farmacología , Antidepresivos de Segunda Generación/farmacología , Antidepresivos Tricíclicos/farmacología , Ciclopropanos/farmacología , Imipramina/farmacología , Paroxetina/farmacología , Inhibidores Selectivos de la Recaptación de Serotonina/farmacología , Fases del Sueño/efectos de los fármacos , Animales , Conducta Animal/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Masculino , Milnaciprán , Ratas , Sueño/efectos de los fármacos , Sueño REM/efectos de los fármacos , Vigilia/efectos de los fármacos
17.
Am J Reprod Immunol ; 47(2): 72-81, 2002 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11900591

RESUMEN

PROBLEM: Normal pregnancy has been described as both a pro-inflammatory condition and a T helper (Th)2-dominated state. Deviations in the percentage of different subpopulations of circulating leukocytes have been detected, although with conflicting results. This study was designed to analyse further the phenotype of subpopulations of peripheral blood leukocytes in normal pregnant women. METHOD OF STUDY: Whole-blood flow cytometry was used to differentiate subsets of leukocytes using directly labeled monoclonal antibodies to specific cell surface antigens and to a panel of activation-associated markers in 33 normal pregnant women in their third trimester and in 26 non-pregnant controls. RESULTS: We found a significant increase in the proportion of granulocytes and of CD8+ T lymphocytes during pregnancy. Up-regulation of the expression of adhesion molecules was observed on granulocytes, monocytes and T lymphocytes. CONCLUSIONS: Pregnancy alters the representation of leukocyte subpopulations in the maternal circulation and is associated with systemic activation of leukocytes.


Asunto(s)
Leucocitos/inmunología , Activación de Linfocitos/inmunología , Embarazo/inmunología , Adulto , Antígenos CD/biosíntesis , Antígenos CD/inmunología , Moléculas de Adhesión Celular/biosíntesis , Moléculas de Adhesión Celular/inmunología , Femenino , Citometría de Flujo , Granulocitos/inmunología , Humanos , Inmunofenotipificación , Monocitos/inmunología
18.
J Autoimmun ; 16(1): 3-13, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11221991

RESUMEN

Although the etiopathogenesis of idiopathic dilated cardiomyopathy (IDC) is still unclear, it is widely accepted that a complex interplay between viral infections and immune mechanisms is the basis of disease genesis. Previously, we showed that heart-infiltrating T cells of patients suffering from acute, fulminant Coxsackie virus B3+-IDC shared a preferential usage of three variable gene segments of the T cell receptor beta chain-(TCR-Vbeta) encoding families Vbeta3, 7 and 13.1. This indicated the possible presence of a superantigen-driven immune response. Here, we further investigated the IDC immunological scenario by analysing different phenotypes of heart-infiltrating cells: TCR repertoires, cytokine expression and presence of enterovirus-specific antigens. IDC patients who underwent heart transplantation at different times after the onset of heart failure were studied. A cardiac infiltrate of CD4+ and CD8+ T cells was present together with activated macrophages. Furthermore, the same Vbeta gene families, previously found to be skewed in hearts from fulminant cases of CVB3+-IDC, together with two additional Vbeta gene families, Vbeta1 and 5B, were increased. IL-1beta, IL-2, IL-6 and IFN-gamma were expressed in the myocardium while others, like IL-4 were not. In conclusion, an orchestrated complex of immune mechanisms seems to be the basis of IDC etiopathogenesis.


Asunto(s)
Cardiomiopatía Dilatada/inmunología , Citocinas/genética , Receptores de Antígenos de Linfocitos T alfa-beta/análisis , Antígenos Virales/análisis , Antígenos CD4/biosíntesis , Antígenos CD8/biosíntesis , Cardiomiopatía Dilatada/patología , Cardiomiopatía Dilatada/virología , Enterovirus Humano B/genética , Enterovirus Humano B/inmunología , Expresión Génica , Antígenos HLA-DQ/clasificación , Cadenas alfa de HLA-DQ , Cadenas beta de HLA-DQ , Prueba de Histocompatibilidad , Humanos , Técnicas para Inmunoenzimas , Interferón gamma/genética , Interleucina-1/genética , Interleucina-2/genética , Interleucina-4/genética , Interleucina-6/genética , Leucocitos Mononucleares/inmunología , Miocarditis/inmunología , Miocardio/inmunología , Miocardio/patología , Picornaviridae/genética , Picornaviridae/aislamiento & purificación , ARN Mensajero , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
19.
Transplantation ; 70(9): 1275-83, 2000 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-11087141

RESUMEN

BACKGROUND: Alpha1,3-galactosyltransferase (alpha1,3GT) is an enzyme that produces carbohydrate chains termed alphaGal epitopes found in most mammals, although some species of higher primates, including human, are notable exceptions. The evolutionary origin of the lost alpha1,3GT enzyme activity is not yet known, although it has been suggested that the promoter activity of this gene in the ancestors of higher primates was inactivated. METHODS: We used 5'-or 3'-RACE, GenomeWalking, reverse transcriptase polymerase chain reaction (RT-PCR) and dual Luciferase reporter assay for identification of the full-length cDNA, which includes the transcription initiation site and the promoter region of porcine alpha1,3GT gene. RESULTS: The region around exon 1 is guanine and cytosine (GC)-rich (about 70%), comprising a CpG island spanning more than 1.5 kbp. The 5'-flanking region of exon 1 contains multiple transcription factor consensus motifs, including GC-box, SP1, AP2, and GATA-box sites, in the absence of TATA or CAAT-box sequences. The entire gene consists of three 5' noncoding and six coding region exons spanning more than 52 kbp. Detailed analysis of alpha1,3GT transcripts revealed two major alternative splicing patterns in the 5'-untranslated region (5'-UTR) and evidence for minor splicing activity that occurs in a tissue-specific manner. Interspecies comparison of 5'-UTR shows minimal homology between porcine and murine sequences except for exon 2, which suggests that the regulatory regions differ among species. CONCLUSIONS: These observations have important implications for experiments involving genetic manipulation of the alpha1,3GT gene in transgenic animals in terms of promoter utilization, and particularly in genetically engineering cells for the animal cloning technology by nuclear transfer.


Asunto(s)
Galactosiltransferasas/genética , Animales , Secuencia de Bases , Bovinos , Exones , Intrones , Datos de Secuencia Molecular , Regiones Promotoras Genéticas , Sitios de Empalme de ARN , ARN Mensajero , Porcinos , Transcripción Genética
20.
Eur J Neurosci ; 12(9): 3361-74, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10998119

RESUMEN

The pallido-subthalamic pathway powerfully controls the output of the basal ganglia circuitry and has been implicated in movement disorders observed in Parkinson's disease (PD). To investigate the normal functioning of this pathway across the sleep-wake cycle, single-unit activities of subthalamic nucleus (STN) and globus pallidus (GP) neurons were examined, together with cortical electroencephalogram and nuchal muscular activity, in non-anaesthetized head-restrained rats. STN neurons shifted from a random discharge in wakefulness (W) to a bursting pattern in slow wave sleep (SWS), without any change in their mean firing rate. This burst discharge occurred in the 1-2 Hz range, but was not correlated with cortical slow wave activity. In contrast, GP neurons, with a mean firing rate higher in W than in SWS, exhibited a relatively regular discharge whatever the state of vigilance. During paradoxical sleep, both STN and GP neurons increased markedly their mean firing rate relative to W and SWS. Our results are not in agreement with the classical 'direct/indirect' model of the basal ganglia organization, as an inverse relationship between STN and GP activities is not observed under normal physiological conditions. Actually, because the STN discharge pattern appears dependent on coincident cortical activity, this nucleus can hardly be viewed as a relay along the indirect pathway, but might rather be considered as an input stage conveying corticothalamic information to the basal ganglia.


Asunto(s)
Nivel de Alerta/fisiología , Globo Pálido/citología , Globo Pálido/fisiología , Núcleo Subtalámico/citología , Núcleo Subtalámico/fisiología , Animales , Ritmo Circadiano/fisiología , Condicionamiento Psicológico/fisiología , Electroencefalografía , Electromiografía , Masculino , Neuronas/fisiología , Ratas , Ratas Sprague-Dawley , Restricción Física/instrumentación , Sueño/fisiología , Sueño REM/fisiología , Vigilia/fisiología
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