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Amyotrophic lateral sclerosis (ALS) is an extremely complex neurodegenerative disease involving different cell types, but motoneuronal loss represents its main pathological feature. Moreover, compensatory plastic changes taking place in parallel to neurodegeneration are likely to affect the timing of ALS onset and progression and, interestingly, they might represent a promising target for disease-modifying treatments. Therefore, a simplified animal model mimicking motoneuronal loss without the other pathological aspects of ALS has been established by means of intramuscular injection of cholera toxin-B saporin (CTB-Sap), which is a targeted neurotoxin able to kill motoneurons by retrograde suicide transport. Previous studies employing the mouse CTB-Sap model have proven that spontaneous motor recovery is possible after a subtotal removal of a spinal motoneuronal pool. Although these kinds of plastic changes are not enough to counteract the functional effects of the progressive motoneuron degeneration, it would nevertheless represent a promising target for treatments aiming to postpone ALS onset and/or delay disease progression. Herein, the mouse CTB-Sap model has been used to test the efficacy of mitochondrial division inhibitor 1 (Mdivi-1) as a tool to counteract the CTB-Sap toxicity and/or to promote neuroplasticity. The homeostasis of mitochondrial fission/fusion dynamics is indeed important for cell integrity, and it could be affected during neurodegeneration. Lesioned mice were treated with Mdivi-1 and then examined by a series of behavioral test and histological analyses. The results have shown that the drug may be capable of reducing functional deficits after the lesion and promoting synaptic plasticity and neuroprotection, thus representing a putative translational approach for motoneuron disorders.
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Esclerose Lateral Amiotrófica , Modelos Animais de Doenças , Dinâmica Mitocondrial , Neurônios Motores , Animais , Neurônios Motores/efeitos dos fármacos , Neurônios Motores/metabolismo , Neurônios Motores/patologia , Dinâmica Mitocondrial/efeitos dos fármacos , Camundongos , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/tratamento farmacológico , Esclerose Lateral Amiotrófica/patologia , Toxina da Cólera/metabolismo , Saporinas , Quinazolinonas/farmacologia , Plasticidade Neuronal/efeitos dos fármacos , Masculino , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismoRESUMO
In recent years, the landscape of diagnostic imaging has undergone a significant transformation with the emergence of home radiology, challenging the traditional paradigm. This shift, bringing diagnostic imaging directly to patients, has gained momentum and has been further accelerated by the global COVID-19 pandemic, highlighting the increasing importance and convenience of decentralized healthcare services. This study aims to offer a nuanced understanding of the attitudes and experiences influencing the integration of in-home radiography into contemporary healthcare practices. The research methodology involves a survey administered through Computer-Aided Web Interviewing (CAWI) tools, enabling real-time engagement with a diverse cohort of medical radiology technicians in the health domain. A second CAWI tool is submitted to experts to assess their feedback on the methodology. The survey explores key themes, including perceived advantages and challenges associated with domiciliary imaging, its impact on patient care, and the technological intricacies specific to conducting radiologic procedures outside the conventional clinical environment. Findings from a sample of 26 medical radiology technicians (drawn from a larger pool of 186 respondents) highlight a spectrum of opinions and constructive feedback. Enthusiasm is evident for the potential of domiciliary imaging to enhance patient convenience and provide a more patient-centric approach to healthcare. Simultaneously, this study suggests areas of intervention to improve the diffusion of home-based radiology. The methodology based on CAWI tools proves instrumental in the efficiency and depth of data collection, as evaluated by 16 experts from diverse professional backgrounds. The dynamic and responsive nature of this approach allows for a more allocated exploration of technicians' opinions, contributing to a comprehensive understanding of the evolving landscape of medical imaging services. Emphasis is placed on the need for national and international initiatives in the field, supported by scientific societies, to further explore the evolving landscape of teleradiology and the integration of artificial intelligence in radiology. This study encourages expansion involving other key figures in this practice, including, naturally, medical radiologists, general practitioners, medical physicists, and other stakeholders.
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(Background) Domiciliary radiology, which originated in pioneering studies in 1958, has transformed healthcare, particularly during the COVID-19 pandemic, through advancements such as miniaturization and digitization. This evolution, driven by the synergy of advanced technologies and robust data networks, reshapes the intersection of domiciliary radiology and mobile technology in healthcare delivery. (Objective) The objective of this study is to overview the reviews in this field with reference to the last five years to face the state of development and integration of this practice in the health domain. (Methods) A review was conducted on PubMed and Scopus, applying a standard checklist and a qualification process. The outcome detected 21 studies. (Key Content and Findings) The exploration of mobile and domiciliary radiology unveils a compelling and optimistic perspective. Notable strides in this dynamic field include the integration of Artificial Intelligence (AI), revolutionary applications in telemedicine, and the educational potential of mobile devices. Post-COVID-19, telemedicine advances and the influential role of AI in pediatric radiology signify significant progress. Mobile mammography units emerge as a solution for underserved women, highlighting the crucial importance of early breast cancer detection. The investigation into domiciliary radiology, especially with mobile X-ray equipment, points toward a promising frontier, prompting in-depth research for comprehensive insights into its potential benefits for diverse populations. The study also identifies limitations and suggests future exploration in various domains of mobile and domiciliary radiology. A key recommendation stresses the strategic prioritization of multi-domain technology assessment initiatives, with scientific societies' endorsement, emphasizing regulatory considerations for responsible and ethical technology integration in healthcare practices. The broader landscape of technology assessment should aim to be innovative, ethical, and aligned with societal needs and regulatory standards. (Conclusions) The dynamic state of the field is evident, with active exploration of new frontiers. This overview also provides a roadmap, urging scholars, industry players, and regulators to collectively contribute to the further integration of this technology in the health domain.
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Noradrenaline (NA) depletion occurs in Alzheimer's disease (AD); however, its relationship with the pathological expression of Tau and transactive response DNA-binding protein 43 (TDP-43), two major hallmarks of AD, remains elusive. Here, increasing doses of a selective noradrenergic immunotoxin were injected into developing rats to generate a model of mild or severe NA loss. At about 12 weeks post-lesion, dose-dependent working memory deficits were detected in these animals, associated with a marked increase in cortical and hippocampal levels of TDP-43 phosphorylated at Ser 409/410 and Tau phosphorylated at Thr 217. Notably, the total levels of both proteins were largely unaffected, suggesting a direct relationship between neocortical/hippocampal NA depletion and the phosphorylation of pathological Tau and TDP-43 proteins. As pTD43 is present in 23% of AD cases and pTau Thr217 has been detected in patients with mild cognitive impairment that eventually would develop into AD, improvement of noradrenergic function in AD might represent a viable therapeutic approach with disease-modifying potential.
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Recent evidence has supported the hypothesis that amyotrophic lateral sclerosis (ALS) is a multi-step disease, as the onset of symptoms occurs after sequential exposure to a defined number of risk factors. Despite the lack of precise identification of these disease determinants, it is known that genetic mutations may contribute to one or more of the steps leading to ALS onset, the remaining being linked to environmental factors and lifestyle. It also appears evident that compensatory plastic changes taking place at all levels of the nervous system during ALS etiopathogenesis may likely counteract the functional effects of neurodegeneration and affect the timing of disease onset and progression. Functional and structural events of synaptic plasticity probably represent the main mechanisms underlying this adaptive capability, causing a significant, although partial and transient, resiliency of the nervous system affected by a neurodegenerative disease. On the other hand, the failure of synaptic functions and plasticity may be part of the pathological process. The aim of this review was to summarize what it is known today about the controversial involvement of synapses in ALS etiopathogenesis, and an analysis of the literature, although not exhaustive, confirmed that synaptic dysfunction is an early pathogenetic process in ALS. Moreover, it appears that adequate modulation of structural and functional synaptic plasticity may likely support function sparing and delay disease progression.
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Esclerose Lateral Amiotrófica , Doenças Neurodegenerativas , Humanos , Esclerose Lateral Amiotrófica/genética , Neurônios Motores/patologia , Doenças Neurodegenerativas/patologia , Sinapses/patologia , Plasticidade Neuronal/fisiologiaRESUMO
Loss of noradrenaline (NA)-rich afferents from the Locus Coeruleus (LC) ascending to the hippocampal formation has been reported to dramatically affect distinct aspects of cognitive function, in addition to reducing the proliferation of neural progenitors in the dentate gyrus. Here, the hypothesis that reinstating hippocampal noradrenergic neurotransmission with transplanted LC-derived neuroblasts would concurrently normalize both cognitive performance and adult hippocampal neurogenesis was investigated. Post-natal day (PD) 4 rats underwent selective immunolesioning of hippocampal noradrenergic afferents followed, 4 days later, by the bilateral intrahippocampal implantation of LC noradrenergic-rich or control cerebellar (CBL) neuroblasts. Starting from 4 weeks and up to about 9 months post-surgery, sensory-motor and spatial navigation abilities were evaluated, followed by post-mortem semiquantitative tissue analyses. All animals in the Control, Lesion, Noradrenergic Transplant and Control CBL Transplant groups exhibited normal sensory-motor function and were equally efficient in the reference memory version of the water maze task. By contrast, working memory abilities were seen to be consistently impaired in the Lesion-only and Control CBL-Transplanted rats, which also exhibited a virtually complete noradrenergic fiber depletion and a significant 62-65% reduction in proliferating 5-bromo-2'deoxyuridine (BrdU)-positive progenitors in the dentate gyrus. Notably, the noradrenergic reinnervation promoted by the grafted LC, but not cerebellar neuroblasts, significantly ameliorated working memory performance and reinstated a fairly normal density of proliferating progenitors. Thus, LC-derived noradrenergic inputs may act as positive regulators of hippocampus-dependent spatial working memory possibly via the concurrent maintenance of normal progenitor proliferation in the dentate gyrus.
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Memória de Curto Prazo , Norepinefrina , Ratos , Animais , Hipocampo , Neurogênese , Memória EspacialRESUMO
Severe loss of cholinergic neurons in the basal forebrain nuclei and of noradrenergic neurons in the locus coeruleus are almost invariant histopathological hallmarks of Alzheimer's disease. However, the role of these transmitter systems in the spectrum of cognitive dysfunctions typical of the disease is still unclear, nor is it yet fully known whether do these systems interact and how. Selective ablation of either neuronal population, or both of them combined, were produced in developing animals to investigate their respective and/or concurrent contribution to spatial learning and memory, known to be severely affected in Alzheimer's disease. Single or double lesions were created in 4-8 days old rats by bilateral intraventricular infusion of two selective immunotoxins. At about 16 weeks of age, the animals underwent behavioural tests specifically designed to evaluate reference and working memory abilities, and their brains were later processed for quantitative morphological analyses. Animals with lesion to either system alone showed no significant reference memory deficits which, by contrast, were evident in the double-lesioned subjects. These animals could not adopt an efficient search strategy on a given testing day and were unable to transfer all relevant information to the next day, suggesting deficits in acquisition, storage and/or recall. Only animals with single noradrenergic or double lesions exhibited impaired working memory. Interestingly, ablation of cholinergic afferents to the hippocampus stimulated a robust ingrowth of thick fibres from the superior cervical ganglion which, however, did not appear to have contributed to the observed cognitive performance. Ascending cholinergic and noradrenergic afferents to the hippocampus and neocortex appear to be primarily involved in the regulation of different cognitive domains, but they may functionally interact, mainly at hippocampal level, for sustaining normal learning and memory. Moreover, these transmitter systems are likely to compensate for each other, but apparently not via ingrowing sympathetic fibres.
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A complex interaction between genetic and external factors determines the development of amyotrophic lateral sclerosis (ALS). Epidemiological studies on large patient cohorts have suggested that ALS is a multi-step disease, as symptom onset occurs only after exposure to a sequence of risk factors. Although the exact nature of these determinants remains to be clarified, it seems clear that: (i) genetic mutations may be responsible for one or more of these steps; (ii) other risk factors are probably linked to environment and/or to lifestyle, and (iii) compensatory plastic changes taking place during the ALS etiopathogenesis probably affect the timing of onset and progression of disease. Current knowledge on ALS mechanisms and therapeutic targets, derives mainly from studies involving superoxide dismutase 1 (SOD1) transgenic mice; therefore, it would be fundamental to verify whether a multi-step disease concept can also be applied to these animal models. With this aim, a meta-analysis study has been performed using a collection of primary studies (n = 137), selected according to the following criteria: (1) the studies should employ SOD1 transgenic mice; (2) the studies should entail the presence of a disease-modifying experimental manipulation; (3) the studies should make use of Kaplan-Meier plots showing the distribution of symptom onset and lifespan. Then, using a subset of this study collection (n = 94), the effects of treatments on key molecular mechanisms, as well as on the onset and progression of disease have been analysed in a large population of mice. The results are consistent with a multi-step etiopathogenesis of disease in ALS mice (including two to six steps, depending on the particular SOD1 mutation), closely resembling that observed in patient cohorts, and revealed an interesting relationship between molecular mechanisms and disease manifestation. Thus, SOD1 mouse models may be considered of high predictive value to understand the determinants of disease onset and progression, as well as to identify targets for therapeutic interventions.
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Esclerose Lateral Amiotrófica , Camundongos , Animais , Esclerose Lateral Amiotrófica/patologia , Superóxido Dismutase-1/genética , Superóxido Dismutase-1/uso terapêutico , Superóxido Dismutase/genética , Camundongos Transgênicos , Mutação , Modelos Animais de Doenças , Progressão da DoençaRESUMO
Care robots represent an opportunity for the health domain. The use of these devices has important implications. They can be used in surgical operating rooms in important and delicate clinical interventions, in motion, in training-and-simulation, and cognitive and rehabilitation processes. They are involved in continuous processes of evolution in technology and clinical practice. Therefore, the introduction into routine clinical practice is difficult because this needs the stability and the standardization of processes. The agreement tools, in this case, are of primary importance for the clinical acceptance and introduction. The opinion focuses on the Consensus Conference tool and: (a) highlights its potential in the field; (b) explores the state of use; (c) detects the peculiarities and problems (d) expresses ideas on how improve its diffusion.
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Care robots represent an opportunity for the health domain. The use of these robots has important implications. They can be used in surgery, rehabilitation, assistance, therapy, and other medical fields. Therefore, care robots (CR)s, have both important physical and psychological implications during their use. Furthermore, these devices, meet important data in clinical applications. These data must be protected. Therefore, cybersecurity (CS) has become a crucial characteristic that concerns all the involved actors. The study investigated the collocation of CRs in the context of CS studies in the health domain. Problems and peculiarities of these devices, with reference to the CS, were faced, investigating in different scientific databases. Highlights, ranging also from ethics implications up to the regulatory legal framework (ensuring safety and cybersecurity) have been reported. Models and cyber-attacks applicable on the CRs have been identified.
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Motoneuronal loss is the main feature of amyotrophic lateral sclerosis, although pathogenesis is extremely complex involving both neural and muscle cells. In order to translationally engage the sonic hedgehog pathway, which is a promising target for neural regeneration, recent studies have reported on the neuroprotective effects of clobetasol, an FDA-approved glucocorticoid, able to activate this pathway via smoothened. Herein we sought to examine functional, cellular, and metabolic effects of clobetasol in a neurotoxic mouse model of spinal motoneuronal loss. We found that clobetasol reduces muscle denervation and motor impairments in part by restoring sonic hedgehog signaling and supporting spinal plasticity. These effects were coupled with reduced pro-inflammatory microglia and reactive astrogliosis, reduced muscle atrophy, and support of mitochondrial integrity and metabolism. Our results suggest that clobetasol stimulates a series of compensatory processes and therefore represents a translational approach for intractable denervating and neurodegenerative disorders.
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Esclerose Lateral Amiotrófica/tratamento farmacológico , Clobetasol/farmacologia , Glucocorticoides/farmacologia , Proteínas Hedgehog/metabolismo , Atividade Motora/efeitos dos fármacos , Neurônios Motores/efeitos dos fármacos , Músculo Esquelético/inervação , Plasticidade Neuronal/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Coluna Vertebral/efeitos dos fármacos , Esclerose Lateral Amiotrófica/induzido quimicamente , Esclerose Lateral Amiotrófica/imunologia , Esclerose Lateral Amiotrófica/metabolismo , Animais , Estudos de Casos e Controles , Toxina da Cólera , Bases de Dados Genéticas , Modelos Animais de Doenças , Metabolismo Energético/efeitos dos fármacos , Humanos , Mediadores da Inflamação/metabolismo , Masculino , Camundongos da Linhagem 129 , Mitocôndrias Musculares/efeitos dos fármacos , Mitocôndrias Musculares/metabolismo , Mitocôndrias Musculares/patologia , Neurônios Motores/imunologia , Neurônios Motores/metabolismo , Teste de Campo Aberto , Saporinas , Transdução de Sinais , Receptor Smoothened/agonistas , Receptor Smoothened/metabolismo , Coluna Vertebral/imunologia , Coluna Vertebral/metabolismo , Coluna Vertebral/fisiopatologiaRESUMO
The technological innovation of digital contact tracing (DCT) has certainly characterized the COVID-19 pandemic, as compared to the previous ones. Based on the first studies, considerable support was expected from smartphone applications ("apps") for DCT. This commentary focuses on digital contact tracing. Its contributions are threefold: (a) Recall the initial expectations of these technologies and the state of diffusion. (b) Deal with the introduction of the app "Immuni" in Italy, while also highlighting the initiatives undertaken at the government level. (c) Report the state of diffusion and use of this App. The commentary ends by proposing some reflections on the continuation of this investigation in Italy.
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Advances in functional imaging are supporting neurosurgery and radiotherapy for glioblastoma, which still remains the most aggressive brain tumor with poor prognosis. The typical infiltration pattern of glioblastoma, which impedes a complete surgical resection, is coupled with a high rate of invasiveness and radioresistance, thus further limiting efficient therapy, leading to inevitable and fatal recurrences. Hypoxia is of crucial importance in gliomagenesis and, besides reducing radiotherapy efficacy, also induces cellular and molecular mediators that foster proliferation and invasion. In this review, we aimed at analyzing the biological mechanism of glioblastoma invasiveness and radioresistance in hypoxic niches of glioblastoma. We also discussed the link between hypoxia and radiation-induced radioresistance with activation of SRC proto-oncogene non-receptor tyrosine kinase, prospecting potential strategies to overcome the current limitation in glioblastoma treatment.
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BACKGROUND: Neuropathic pain is caused by primary lesion or dysfunction of either peripheral or central nervous system. Due to its complex pathogenesis, often related to a number of comorbidities, such as cancer, neurodegenerative and neurovascular diseases, neuropathic pain still represents an unmet clinical need, lacking long-term effective treatment and complex case-by-case approach. AIM AND METHODS: We analyzed the recent literature on the role of selective voltage-sensitive sodium, calcium and potassium permeable channels and non-selective gap junctions (GJs) and hemichannels (HCs) in establishing and maintaining chronic neuropathic conditions. We finally focussed our review on the role of extracellular microenvironment modifications induced by resident glial cells and on the recent advances in cell-to-cell and cell-to-extracellular environment communication in chronic neuropathies. CONCLUSION: In this review, we provide an update on the current knowledge of neuropathy chronicization processes with a focus on both neuronal and glial ion channels, as well as on channel-mediated intercellular communication.
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Comunicação Celular/fisiologia , Canais Iônicos/fisiologia , Neuralgia/etiologia , Animais , Doença Crônica , Conexina 43/fisiologia , Junções Comunicantes/fisiologia , HumanosRESUMO
Amyotrophic lateral sclerosis (ALS) is one of the most common motoneuronal disease, characterized by motoneuronal loss and progressive paralysis. Despite research efforts, ALS remains a fatal disease, with a survival of 2-5 years after disease onset. Numerous gene mutations have been correlated with both sporadic (sALS) and familiar forms of the disease, but the pathophysiological mechanisms of ALS onset and progression are still largely uncertain. However, a common profile is emerging in ALS pathological features, including misfolded protein accumulation and a cross-talk between neuroinflammatory and degenerative processes. In particular, astrocytes and microglial cells have been proposed as detrimental influencers of perineuronal microenvironment, and this role may be exerted via gap junctions (GJs)- and hemichannels (HCs)-mediated communications. Herein we investigated the role of the main astroglial GJs-forming connexin, Cx43, in human ALS and the effects of focal spinal cord motoneuronal depletion onto the resident glial cells and Cx43 levels. Our data support the hypothesis that motoneuronal depletion may affect glial activity, which in turn results in reactive Cx43 expression, further promoting neuronal suffering and degeneration.
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Esclerose Lateral Amiotrófica , Conexina 43/metabolismo , Neurônios Motores/metabolismo , Medula Espinal , Adulto , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/fisiopatologia , Animais , Astrócitos/metabolismo , Conexina 43/genética , Modelos Animais de Doenças , Feminino , Junções Comunicantes/metabolismo , Proteína Glial Fibrilar Ácida/metabolismo , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Neurônios Motores/citologia , Medula Espinal/química , Medula Espinal/citologia , Medula Espinal/metabolismo , Medula Espinal/fisiopatologiaRESUMO
Multiple myeloma (MM) is a clonal B-cell malignancy characterized by an accumulation of plasma cells (PC) in the bone marrow (BM), leading to bone loss and BM failure. Osteolytic bone disease is a common manifestation observed in MM patients and represents the most severe cause of morbidity, leading to progressive skeletal damage and disabilities. Pathogenetic mechanisms of MM bone disease are closely linked to PCs and osteoclast (OCs) hyperactivity, coupled with defective osteoblasts (OBs) function that is unable to counteract bone resorption. The aim of the present study was to investigate the effects of Ixazomib, a third-generation proteasome inhibitor, on osteoclastogenesis and osteogenic differentiation. We found that Ixazomib was able to reduce differentiation of human monocytes into OCs and to inhibit the expression of OC markers when added to the OC medium. Concurrently, Ixazomib was able to stimulate osteogenic differentiation of human mesenchymal stromal cells (MSCs), increasing osteogenic markers, either alone or in combination with the osteogenic medium. Given the key role of Sonic Hedgehog (SHH) signaling in bone homeostasis, we further investigated Ixazomib-induced SHH pathway activation. This set of experiments showed that Ixazomib, but not Bortezomib, was able to bind the Smoothened (SMO) receptor leading to nuclear translocation of GLI1 in human MSCs. Moreover, we demonstrated that PCs act as GLI1 suppressors on MSCs, thus reducing the potential of MSCs to differentiate in OBs. In conclusion, our data demonstrated that Ixazomib regulates bone remodeling by decreasing osteoclastogenesis and prompting osteoblast differentiation via the canonical SHH signaling pathway activation, thus, representing a promising therapeutic option to improve the complex pathological condition of MM patients.
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Olfactory Ensheathing Cells (OECs) are glial cells able to secrete different neurotrophic growth factors and thus promote axonal growth, also acting as a mechanical support. In the olfactory system, during development, they drive the non-myelinated axons of the Olfactory Receptor Neurons (ORNs) towards the Olfactory Bulb (OB). Ghrelin (Ghre), a gut-brain peptide hormone, and its receptor (GHS-R 1a) are expressed in different parts of the central nervous system. In the last few years, this peptide has stimulated particular interest as results show it to be a neuroprotective factor with antioxidant, anti-inflammatory and anti-apoptotic properties. Our previous studies showed that OB mitral cells express Ghre, thus being able to play an important role in regulating food behavior in response to odors. In this study, we investigated the presence of Ghre and GHS-R 1a in primary mouse OECs. The expression of both Ghre and its receptor was assessed by an immunocytochemical technique, Western Blot and Polymerase Chain Reaction (PCR) analysis. Our results demonstrated that OECs are able to express both Ghre and GHS-R 1a and that these proteins are detectable after extensive passages in vitro; in addition, PCR analysis further confirmed these data. Therefore, we can hypothesize that Ghre and GHS-R 1a interact with a reinforcement function, in the peripheral olfactory circuit, providing a neurotrophic support to the synaptic interaction between ORNs and mitral cells.
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Grelina/metabolismo , Fatores de Crescimento Neural/metabolismo , Neuroglia/metabolismo , Bulbo Olfatório/metabolismo , Receptores de Grelina/metabolismo , Animais , Células Cultivadas , CamundongosRESUMO
Plastic changes have been reported in the SOD1-G93A mouse model of amyotrophic lateral sclerosis, a disorder characterized by progressive motoneuronal loss; however, whether these changes related with the onset and development of motor impairments is still unclear. Here, the functional and anatomical changes taking place in SOD1-G93A mice and their time course were investigated during ongoing motoneuronal degeneration. Starting from about 4 postnatal weeks, SOD1-G93A and wild-type (WT) mice were evaluated in the rotarod test, to be sacrificed at about 12-13 or 19 weeks of age, and their lumbar spinal cords were processed for histo- and immunohistochemistry. Compared to age-matched WT controls, 12 weeks-old SOD1-G93A mice exhibited relatively mild or no motor impairments in the rotarod test, in spite of a dramatic (≈60%, as estimated by stereology) loss of choline acetyl-transferase (ChAT)-immunoreactive motoneurons which remained virtually unchanged in SOD1-G93A mice surviving up to 19 weeks. Notably, the functional sparing in SOD1-G93A mice at 12 weeks was paralleled by a marked ≈50% increase in motoneuron volume and a near-normal density of acetylcholinesterase-positive process arborization, which was significantly increased when analyzed as ratio to the decreased number of ChAT-positive motoneurons. By contrast, at 19 weeks, when motor deficits had become dramatically evident, both measures were found reverted to about 50-60% of control values. Thus, at specific stages during the progression of the disease, robust compensatory events take place in surviving motoneurons of SOD1-G93A mice, which sustain motor performance, and whose full understanding may highlight a valuable therapeutic opportunity window.
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Esclerose Lateral Amiotrófica/patologia , Esclerose Lateral Amiotrófica/fisiopatologia , Neurônios Motores/patologia , Degeneração Neural/patologia , Degeneração Neural/fisiopatologia , Animais , Modelos Animais de Doenças , Progressão da Doença , Feminino , Camundongos , Camundongos Transgênicos , Atividade Motora/fisiologia , Medula Espinal/patologia , Medula Espinal/fisiopatologiaRESUMO
Neuropathic pain is a chronic condition triggered by lesions to the somatosensory nervous system in which pain stimuli occur spontaneously or as pathologically amplified responses. In this scenario, the exchange of signaling molecules throughout cell-to-cell and cell-to-extracellular environment communications plays a key role in the transition from acute to chronic pain. As such, connexin 43 (Cx43), the core glial gap junction and hemichannel-forming protein, is considered a triggering factor for disease chronicization in the central nervous system (CNS). Drugs targeting µ opioid receptors (MOR) are currently used for moderate to severe pain conditions, but their use in chronic pain is limited by the tolerability profile. δ opioid receptors (DOR) have become attractive targets for the treatment of persistent pain and have been associated with the inhibition of pain-sustaining factors. Moreover, it has been shown that simultaneous targeting of MOR and DOR leads to an improved pharmacological fingerprint. Herein, we aimed to study the effects of the benzomorphan ligand LP2, a multitarget MOR/DOR agonist, in an experimental model of neuropathic pain induced by the unilateral sciatic nerve chronic constriction injury (CCI) on male Sprague-Dawley rats. Results showed that LP2 significantly ameliorated mechanical allodynia from the early phase of treatment up to 21 days post-ligatures. We additionally showed that LP2 prevented CCI-induced Cx43 alterations and pro-apoptotic signaling in the CNS. These findings increase the knowledge of neuropathic pain development and the role of spinal astrocytic Cx43, suggesting new approaches for the treatment of neuropathic pain.
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Astrócitos/metabolismo , Conexina 43/metabolismo , Hiperalgesia/metabolismo , Neuralgia/metabolismo , Receptores Opioides delta/metabolismo , Receptores Opioides mu/metabolismo , Animais , Astrócitos/efeitos dos fármacos , Caspase 3/metabolismo , Constrição Patológica , Meios de Cultivo Condicionados/farmacologia , Modelos Animais de Doenças , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/metabolismo , Proteína Glial Fibrilar Ácida/metabolismo , Gliose/complicações , Gliose/patologia , Hiperalgesia/complicações , Masculino , Neuralgia/complicações , Neuralgia/patologia , Ratos Sprague-Dawley , Corno Dorsal da Medula Espinal/efeitos dos fármacos , Corno Dorsal da Medula Espinal/metabolismo , Regulação para Cima/efeitos dos fármacosRESUMO
Sonic hedgehog (Shh) signaling is a key pathway within the central nervous system (CNS), during both development and adulthood, and its activation via the 7-transmembrane protein Smoothened (Smo) may promote neuroprotection and restoration during neurodegenerative disorders. Shh signaling may also be activated by selected glucocorticoids such as clobetasol, fluocinonide and fluticasone, which therefore act as Smo agonists and hold potential utility for regenerative medicine. However, despite its potential role in neurodegenerative diseases, the impact of Smo-modulation induced by these glucocorticoids on adult neural stem cells (NSCs) and the underlying signaling mechanisms are not yet fully elucidated. The aim of the present study was to evaluate the effects of Smo agonists (i.e., purmorphamine) and antagonists (i.e., cyclopamine) as well as of glucocorticoids (i.e., clobetasol, fluocinonide and fluticasone) on NSCs in terms of proliferation and clonal expansion. Purmorphamine treatment significantly increased NSC proliferation and clonal expansion via GLI-Kruppel family member 1 (Gli1) nuclear translocation and such effects were prevented by cyclopamine co-treatment. Clobetasol treatment exhibited an equivalent pharmacological effect. Moreover, cellular thermal shift assay suggested that clobetasol induces the canonical Smo-dependent activation of Shh signaling, as confirmed by Gli1 nuclear translocation and also by cyclopamine co-treatment, which abolished these effects. Finally, fluocinonide and fluticasone as well as control glucocorticoids (i.e., prednisone, corticosterone and dexamethasone) showed no significant effects on NSCs proliferation and clonal expansion. In conclusion, our data suggest that Shh may represent a druggable target system to drive neuroprotection and promote restorative therapies.