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Stroke is a major healthcare problem worldwide, particularly in the elderly population. Despite limited research on the development of prediction models for mortality in elderly individuals with ischemic stroke, our study aimed to address this knowledge gap. By leveraging data from the Medical Information Mart for Intensive Care IV database, we collected comprehensive raw data pertaining to elderly patients diagnosed with ischemic stroke. Through meticulous screening of clinical variables associated with 28-day mortality, we successfully established a robust nomogram. To assess the performance and clinical utility of our nomogram, various statistical analyses were conducted, including the concordance index, integrated discrimination improvement (IDI), net reclassification index (NRI), calibration curves and decision curve analysis (DCA). Our study comprised a total of 1259 individuals, who were further divided into training (n = 894) and validation (n = 365) cohorts. By identifying several common clinical features, we developed a nomogram that exhibited a concordance index of 0.809 in the training dataset. Notably, our findings demonstrated positive improvements in predictive performance through the IDI and NRI analyses in both cohorts. Furthermore, calibration curves indicated favorable agreement between the predicted and actual incidence of mortality (P > 0.05). DCA curves highlighted the substantial net clinical benefit of our nomogram compared to existing scoring systems used in routine clinical practice. In conclusion, our study successfully constructed and validated a prognostic nomogram, which enables accurate short-term mortality prediction in elderly individuals with ischemic stroke.
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AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Idoso , AVC Isquêmico/diagnóstico , Nomogramas , Acidente Vascular Cerebral/diagnóstico , Calibragem , Cuidados CríticosRESUMO
ABSTRACT: Introduction: The present study aimed to explore the clinical features and long-term outcomes associated with neurologic impairment in patients with cardiac arrest (CA) who received extracorporeal cardiopulmonary resuscitation (ECPR). Methods: A total of 37 adult CA patients who underwent venoarterial extracorporeal membrane oxygenation and were admitted to our department between January 2015 and February 2022 were divided according to neurologic impairment. Baseline and CPR- and ECMO-related characteristics were compared between the two groups. Long-term neurologic outcomes were collected via telephone follow-ups. Results: Twenty-four (64.9%) ECPR-supported patients developed neurologic impairments. The two groups differed significantly in median age (P = 0.026), proportion of intra-aortic balloon pump (IABP) support (P = 0.011), proportion of continuous renal replacement therapy (P = 0.025), and median serum creatinine (Cr) level (P = 0.012) pre-ECMO. The 28-day mortality (P = 0.001), hospital mortality (P = 0.003), median duration from CA to restoration of spontaneous circulation (P = 0.029), proportion of patients with nonpulsatile perfusion (NP) >12 hours (P = 0.040), and median ECMO duration (P = 0.047) were higher in the neurologic impairment group. In contrast, the group without neurologic impairment exhibited a longer median intensive care unit length of stay (P = 0.047), longer median hospital LOS (P = 0.031), and more successful ECMO weaning (P = 0.049). Moreover, NP >12 hours combined with IABP support (odds ratio [OR], 14.769; 95% confidence interval [CI], 1.417~153.889; P = 0.024) and serum Cr level (OR, 1.028; 95% CI, 1.001~1.056; P = 0.043) were independent risk factors for neurologic impairment. Furthermore, neurologic impairment was associated with significantly worse 90-day survival (hazards ratio, 4.218; 95% CI, 1.745~10.2; P = 0.0014). Conclusions: The incidence of neurologic impairment was higher in patients who received ECPR and was closely related to 28-day mortality and discharge survival. NP >12 hours combined with IABP support and serum Cr levels were independent risk factors for neurologic impairments in ECPR-supported patients. Neurologic impairment significantly adversely affected the long-term outcomes of ECPR-supported patients after discharge.
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Reanimação Cardiopulmonar , Oxigenação por Membrana Extracorpórea , Parada Cardíaca , Doenças do Sistema Nervoso , Adulto , Humanos , Estudos Retrospectivos , Parada Cardíaca/terapia , Doenças do Sistema Nervoso/etiologiaRESUMO
BACKGROUND: Sepsis-associated encephalopathy (SAE) is a severe complication of sepsis that affects upwards of half of all sepsis patients. Few studies have examined the etiology and risk factors of SAE among elderly patients. This study was designed to explore the epidemiology of SAE and the risk factors associated with its development in elderly populations. METHODS: This was a retrospective analysis of elderly sepsis patients admitted to our intensive care unit between January 2017 and January 2022. We then compared non-SAE and SAE groups concerning baseline clinicopathological findings, underlying diseases, infection site, disease type, disease severity, biochemical findings, and 28-day mortality. We further stratified patients in the SAE group based on whether or not they survived for 28 days, and we compared the above data between these groups. RESULTS: Of the 222 elderly sepsis patients, 132 (59.46%) had SAE. SAE patients were found to be significantly older than non-SAE patients. Both age and blood sodium concentrations were found to be associated with SAE risk, while elderly sepsis patients without underlying chronic obstructive pulmonary disease (COPD) have a relatively higher risk of developing SAE. The SAE group also had a significantly higher rate of 28-day mortality, and sequential organ failure assessment (SOFA) scores were a risk factor associated with 28-day mortality. DISCUSSION: Among elderly sepsis patients, SAE risk increases with advancing age, higher blood sodium concentrations, and without underlying COPD. SAE incidence is associated with a poorer prognosis, and SOFA scores are independent predictors of increased mortality among elderly SAE patients.
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Doença Pulmonar Obstrutiva Crônica , Encefalopatia Associada a Sepse , Sepse , Humanos , Idoso , Encefalopatia Associada a Sepse/complicações , Encefalopatia Associada a Sepse/epidemiologia , Estudos Retrospectivos , Prognóstico , Sepse/complicações , Sepse/epidemiologia , Fatores de Risco , Doença Pulmonar Obstrutiva Crônica/complicações , SódioRESUMO
Sepsis-associated encephalopathy(SAE) caused by infections outside the central nervous system always presents extensive brain damage.It is common in clinical practice and associated with a poor prognosis.There are problems in the assessing and diagnosing of SAE.Many factors,such as sedation and mechanical ventilation,make it difficult to assess SAE,while electrophysiological examination may play a role in the assessment.We reviewed the studies of electrophysiological techniques such as electroencephalography and somatosensory evoked potentials for monitoring SAE,hoping to provide certain evidence for the clinical evaluation and diagnosis of SAE.
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Encefalopatia Associada a Sepse , Sepse , Humanos , Encefalopatia Associada a Sepse/diagnóstico , Encefalopatia Associada a Sepse/complicações , Sepse/complicações , Sepse/diagnóstico , EletroencefalografiaRESUMO
Background: The main objective of this study was to investigate the role of a multimodal neurological monitoring (MNM)-guided protocol in the precision identification of neural impairment and long-term neurological outcomes in venoarterial extracorporeal membrane oxygenation (VA-ECMO) supported patients. Methods: We performed a cohort study that examined adult patients who underwent VA-ECMO support in our center between February 2010 and April 2021. These patients were retrospectively assigned to the "with MNM group" and the "without MNM group" based on the presence or absence of MNM-guided precision management. The differences in ECMO-related characteristics, evaluation indicators (precision, sensitivity, and specificity) of the MNM-guided protocol, and the long-term outcomes of the surviving patients were measured and compared between the two groups. Results: A total of 63 patients with VA-ECMO support were retrospectively assigned to the without MNM group (n = 35) and the with MNM group (n = 28). The incidence of neural impairment in the without MNM group was significantly higher than that in the with MNM group (82.1 vs. 54.3%, P = 0.020). The MNM group exhibited older median ages [52.5 (39.5, 65.3) vs. 31 (26.5, 48.0), P = 0.008], a higher success rate of ECMO weaning (92.8 vs. 71.4%, P = 0.047), and a lower median duration of building ECMO [40.0 (35.0, 52.0) vs. 58.0 (48.0, 76.0), P = 0.025] and median ECMO duration days [5.0 (4.0, 6.2) vs. 7.0 (5.0, 10.5), P = 0.018] than the group without MNM. The MNM-guided protocol exhibited a higher precision rate (82.1 vs. 60.0%), sensitivity (95.7 vs. 78.9%), and specificity (83.3 vs. 37.5%) in identifying neural impairment in VA-ECMO support patients. There were significant differences in the long-term outcomes of survivors at 1, 3 and 6 months after discharge between the two groups (P < 0.05). However, the results showed no significant differences in ICU length of stay (LOS), hospital LOS, survival to discharge, or 28-day mortality between the two groups (P > 0.05). Conclusion: The MNM-guided protocol is conducive to guiding intensivists in the improvement of cerebral protection therapy for ECMO-supported patients to detect and treat potential neurologic impairment promptly, and then improving long-term neurological outcomes after discharge.
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Background: To explore the epidemiology, clinical features, risk indicators, and long-term outcomes of neurological complications caused by veno-arterial extracorporeal membrane oxygenation (V-A ECMO). Methods: We retrospectively analyzed 60 adult patients who underwent V-A ECMO support in our unit from February 2012 to August 2020. These patients were separated into the neurological complications group (NC group) and the non-neurological complications group (nNC group). The differences in basic data and ECMO data between the two groups were compared. The data of long-term neurological prognosis were collected by telephone follow-up. Results: Thirty-nine patients (65.0%) had neurological complications. There were significant differences between the two groups in terms of median age, hypertension, median blood urea nitrogen, median troponin I (TNI), median lactic acid, pre-ECMO percutaneous coronary intervention, continuous renal replacement therapy (CRRT), median Sequential Organ Failure Assessment score, median Acute Physiology and Chronic Health Evaluation II score, median peak inspiratory pressure, median positive end expiratory pressure, and median fresh frozen plasma (P < 0.05). The median Intensive Care Unit length of stay (ICU LOS), 28-day mortality, median post-ECMO vasoactive inotropic score, non-pulsate perfusion (NP), and median ECMO duration of the NC group were significantly higher than those of the nNC group (P < 0.05). Furthermore, multiple logistic regression analysis revealed that TNI (P = 0.043), CRRT (P = 0.047), and continuous NP > 12 h (P = 0.043) were independent risk indicators for neurological complications in patients undergoing ECMO. Forty-four patients (73.3%) survived after discharge, and 38 patients (63.3%) had Cerebral Performance Category score of 1-2. And there were significant differences between the two groups in long-term neurological outcomes after discharge for 6 months (P < 0.05). Conclusion: The incidence of neurological complications was higher in patients undergoing V-A ECMO and was closely related to adverse outcomes (including ICU LOS and 28-day mortality). TNI, CRRT, and continuous NP > 12 h were independent risk indicators for predicting neurological complications in ECMO supporting patients. And the neurological complications of patients during ECMO support had significant adverse effect on long-term surviving and neurological outcomes of patients after discharge for 6 months.
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BACKGROUND: Gut-microbiota-brain axis links the relationship between intestinal microbiota and sepsis-associated encephalopathy (SAE). However, the key mediators between them remain unclear. METHODS: Memory test was determined by Water maze. Intestinal flora was measured by 16S RNA sequencing. Neurotransmitter was detected by high-performance liquid chromatography (HPLC). Histopathology was determined by H&E, immunofluorescence (IF), and terminal-deoxynucleoitidyl transferase mediated nick end labeling (TUNEL) staining. Flow cytometry was employed to determine the proportion of macrophages. RESULTS: Fecal microbiota transplantation (FMT) relieved hippocampus impairment of SAE rats by inhibiting inflammation cytokine secretion, the expression of IBA-1 and neurotransmitter disturbance, and cell apoptosis and autophagy, accompanied by the reduced M1 polarization and M1 pro-inflammation factors produced by macrophages in mesenteric lymph nodes (MLNs). Actually, M1 polarization in SAE rats depended on intestinal epithelial cell (IEC)-derived exosome. GW4869-initiated inhibition of exosome secretion notably abolished M1 polarization and the secretion of IL-1ß. However, GW4869-mediated improvement of hippocampus impairment was counteracted by the delivery of recombinant interleukin (IL)-1ß to hippocampus. Mechanistically, IEC-derived exosome induced the excessive circulating IL-1ß produced by CP-R048 macrophages, which subsequently induced damage and apoptosis of hippocampal neurons H19-7 in an autophagy-dependent manner. And reactivation of autophagy facilitates intestinal IL-1ß-mediated hippocampal neuron injury. CONCLUSION: Collectively, intestinal flora disturbance induced the exosome release of IECs, which subsequently caused M1 polarization in MLNs and the accumulation of circulating IL-1ß. Circulating IL-1ß promoted the damage and apoptosis of neurons in an autophagy-dependent manner. Possibly, targeting intestinal flora or IEC-derived exosome contributes to the treatment of SAE.
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Exossomos , Encefalopatia Associada a Sepse , Animais , Células Epiteliais , Transplante de Microbiota Fecal , Neurônios , RatosRESUMO
Background: The aim of study was to summarize the clinical characteristics and experience of extracorporeal membrane oxygenation (ECMO) in pregnant and postpartum patients. Methods and Results: We retrospectively reviewed 131 consecutive ECMO patients at our center from May 2015 to May 2021. A total of 10 Chinese patients were pregnant or postpartum at the time of ECMO initiation. Patients ranged in age from 25 to 36 years (median age 30.5 years). The ECMO duration ranged from 3 to 31 days (median duration 8 days). There was a stabilizing trend of acid-base balance and decreasing lactic acid over the 3 days following ECMO initiation. Seven (70%) patients survived at least 48 h after weaning from ECMO. Four (40%) patients survived until discharge, and four (40%) fetuses survived until discharge. Conclusion: ECMO provides a suitable temporary cardiopulmonary support for pregnant and postpartum patients. ECMO shows a favorable effect on short-term stability in critical obstetric patients.
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BACKGROUND: Sepsis-associated encephalopathy (SAE) is a common complication of sepsis that may result in worse outcomes. This study was designed to determine the epidemiology, clinical features, and risk factors of SAE. METHODS: This was a retrospective study of all patients with sepsis who were admitted to the Critical Care Medicine Department of Hangzhou First People's Hospital Affiliated with Zhejiang University School of Medicine from January 2015 to December 2019. RESULTS: A total of 291 sepsis patients were screened, and 127 (43.6%) were diagnosed with SAE. There were significant differences in median age, proportion of underlying diseases such as hypertension, Sequential Organ Failure Assessment (SOFA) score, Acute Physiology and Chronic Health Evaluation II (APACHE II) score, gastrointestinal infections, detection rate of Enterococcus, and 28-day mortality between the SAE and non-SAE groups. Both the SOFA score and APACHE II score were independent risk factors for SAE in patients with sepsis. All 127 SAE patients were divided into survival and non-survival groups. The age, SOFA score, and APACHE II score were independently associated with 28-day mortality in SAE patients. CONCLUSION: In the present retrospective study, nearly half of patients with sepsis developed SAE, which was closely related to poor outcomes. Both the SOFA score and APACHE II score were independent risk factors for predicting the occurrence and adverse outcome of SAE.
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Encefalopatia Associada a Sepse/epidemiologia , APACHE , Idoso , China/epidemiologia , Feminino , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Escores de Disfunção Orgânica , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Encefalopatia Associada a Sepse/microbiologia , Encefalopatia Associada a Sepse/mortalidade , Encefalopatia Associada a Sepse/terapia , Taxa de SobrevidaRESUMO
OBJECTIVES: The present study was undertaken to investigate the effects and related mechanisms of hypothermia on oxidative stress and apoptosis caused by cardiac arrest (CA)-induced brain damage in rats. METHODS: The CA/CPR model was initiated by asphyxia. Body temperature in the normothermia and hypothermia groups was maintained at 37°C ± 0.2°C and 34°C ± 0.2°C, respectively, by surface cooling with an ice pack. First, neurological deficit scores (NDSs) were assessed, and then hippocampus samples were collected at 24 and 72 h after return of spontaneous circulation (ROSC). RESULTS: The NDSs of rats were significantly reduced after CA, and hypothermia ameliorated neurological deficits. Varying degrees of changes in cellular nuclei and mitochondria were observed in the hippocampus following CA; however, morphological changes became less apparent after therapeutic hypothermia. Malondialdehyde (MDA) content and superoxide dismutase (SOD) activity were higher in the hippocampus at 24 h after ROSC. In contrast, hypothermia did not alter MDA content, while SOD activity further increased. Furthermore, hypothermia reversed the caspase-3 enhancement observed in the normothermia group at 24 h after ROSC. CA also inhibited GSK-3ß phosphorylation, promoted Nrf2 translocation to the nucleus, and downregulated HO-1 expression. However, hypothermia significantly reversed these CA-induced changes in GSK-3ß phosphorylation, Nrf2 translocation, and HO-1 expression. CONCLUSION: Hypothermia attenuated CA-induced neurological deficits and hippocampal morphology changes in rats. The protective effect of hypothermia following CA may have been related to inhibition of oxidative stress and apoptosis, and its underlying mechanisms may have been due, at least in part, to activation of the GSK-3ß/Nrf2/HO-1 pathway.
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Apoptose , Lesões Encefálicas/prevenção & controle , Parada Cardíaca/complicações , Hipocampo/metabolismo , Hipotermia Induzida , Estresse Oxidativo , Transdução de Sinais , Animais , Lesões Encefálicas/metabolismo , Lesões Encefálicas/patologia , Modelos Animais de Doenças , Glicogênio Sintase Quinase 3 beta/metabolismo , Heme Oxigenase (Desciclizante)/metabolismo , Hipocampo/ultraestrutura , Masculino , Fator 2 Relacionado a NF-E2/metabolismo , Ratos Sprague-DawleyRESUMO
Cerebral ischemia/reperfusion (I/R) injury often leads to irreversible neuronal injury and even death, and hypothermia is the only therapeutic method that has been proven to be effective. However, the molecular mechanisms underlying the effect of hypothermia treatment on I/R injury have not been fully elucidated. In the present study, we aimed to evaluate the neuroprotective effects and mechanisms of hypothermia against hypoxia/reoxygenation (H/R)-induced neuronal damage. Primary hippocampal neurons were exposed to H/R and were then treated with hypothermia. We observed that hypothermia significantly increased cellular viability, downregulated the expression of pyroptosis-related proteins-including NLR pyrin domain containing 3 (NLRP3), apoptotic speck-like protein containing CARD (ASC), cleaved Caspase-1, and Gasdermin-D (GsdmD) p30-and reduced secretion of the pro-inflammatory cytokines, IL-1ß and IL-18. Additionally, pretreatment with MCC950, a specific small-molecule inhibitor of the NLRP3 inflammasome, yielded a protective effect on cellular viability that was comparable to that of hypothermia treatment. Furthermore, hypothermia also significantly elevated the expression level of phosphatase and tensin homologous protein (PTEN) and activated the phosphorylation levels of protein kinase B (Akt) and glycogen synthase kinase-3ß (GSK-3ß). These protective effects of hypothermia on pyroptosis-related proteins and pro-inflammatory cytokines were partially reversed by the specific PI3K/Akt inhibitor, LY294002. Moreover, the methylated level of PTEN mRNA was elevated in hippocampal neurons upon H/R, whereas this level remained stable in the hypothermia group. Therefore, our findings suggest that hypothermia protects neurons against neuronal H/R-induced pyroptosis, and that m6A-mediated activation of PTEN and the phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K)/Akt/GSK-3ß signaling pathway may play crucial roles during this process.
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Glicogênio Sintase Quinase 3 beta/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Piroptose/fisiologia , Animais , Animais Recém-Nascidos , Hipóxia Celular/fisiologia , Células Cultivadas , Cromonas/farmacologia , Inibidores Enzimáticos/farmacologia , Hipotermia Induzida/métodos , Morfolinas/farmacologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Ratos , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/prevenção & controle , Transdução de Sinais/fisiologiaRESUMO
Mesenchymal stem cells (MSCs) pretreatment is an effective route for improving cell-based therapy of endothelial cell survival, vascular stabilization, and angiogenesis. We hypothesized that the application of human umbilical cord-MSCs (hUC-MSCs) pretreated with angiotensin-II (Ang-II) might be a potential therapeutic approach for severe acute pancreatitis (SAP). Therefore, the effect of Ang-II pretreated hUC-MSCs on SAP was investigated in vitro and in vivo. METHODS: In the present study, human umbilical cord-derived MSCs pretreated with or without Ang-II were delivered through the tail vein of rats 12â¯h after induction of SAP. Pancreatitis severity scores and serum lipase levels, as well as the levels of VEGF and VEGFR2 were evaluated. RESULTS: We found that the administration of Ang-II-MSCs significantly inhibited pancreatic injury, as reflected by reductions of pancreatitis severity scores, serum amylase and serum lipase levels. Furthermore, the reduced apoptotic rate and increased tube formation in human umbilical vein endothelial Cells (HUVEC) were found resulting from the administration of Ang-II-MSC-CM. Moreover, knockdown of VEGFR2 can block the effect of Ang-II-MSC-CM on preventing HUVEC from apoptosis, as well as the capacity of tube formation was also suppressed. In addition, the expression of increased Bcl-2 and alleviated caspase-3 were observed in HUVEC and HUVEC transfectants exposure to Ang-II-MSC-CM. CONCLUSION: Collectively, these results elucidated that the pretreatment of hUC-MSCs with Ang-II improved the outcome of MSC-based therapy for SAP via enhancing angiogenesis and ameliorating endothelial cell dysfunction in a VEGFR2 dependent manner.
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Angiotensina II/farmacologia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Pâncreas/lesões , Pâncreas/patologia , Pancreatite/terapia , Cordão Umbilical/citologia , Doença Aguda , Animais , Apoptose/efeitos dos fármacos , Meios de Cultivo Condicionados/farmacologia , Modelos Animais de Doenças , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Modelos Biológicos , Neovascularização Fisiológica/efeitos dos fármacos , Pâncreas/efeitos dos fármacos , Pancreatite/patologia , Comunicação Parácrina/efeitos dos fármacos , Ratos , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismoRESUMO
Numerous epidemiological studies suggested that there is a variable cancer risk in patients with Parkinson's disease (PD). However, the underlying mechanisms remain unclear. In the present study, the role of metabotropic glutamate receptor 5 (mGluR5) has been investigated in 6-hydroxydopamine (6-OHDA)-induced PD combined with liver cancer both in vitro and in vivo. We found that PD cellular model from 6-OHDA-lesioned MN9D cells suppressed the growth, migration, and invasion of Hepa1-6 cells via down-regulation of mGluR5-mediated ERK and Akt pathway. The application of 2-methyl-6-(phenylethyl)-pyridine and knockdown of mGluR5 further decreased the effect on Hepa-1-6 cells when co-cultured with conditioned media. The effect was increased by (S)-3,5-dihydroxyphenylglycine and overexpression of mGluR5. Moreover, more release of glutamate from 6-OHDA-lesioned MN9D cells suppressed mGluR5-mediated effect of Hepa1-6 cells. Application of riluzole eliminated the increased glutamate release induced by 6-OHDA in MN9D cells and aggravated the suppressive effect on Hepa-1-6 cells. In addition, the growth of implanted liver cancer was inhibited in 6-OHDA induced PD-like rats, and was associated with increased glutamate release in the serum and down-regulation of mGluR5 in tumor tissue. Collectively, these results indicate that selective antagonism of glutamate and mGluR5 has a potentially beneficial effect in both liver cancer and PD, and thus may provide more understanding for the clinical investigation and further an additional therapeutic target for these two diseases.
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Ácido Glutâmico/metabolismo , Neoplasias Hepáticas/metabolismo , Oxidopamina , Doença de Parkinson Secundária/metabolismo , Receptor de Glutamato Metabotrópico 5/metabolismo , Animais , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Modelos Animais de Doenças , Fígado/metabolismo , Fígado/patologia , Neoplasias Hepáticas/patologia , Sistema de Sinalização das MAP Quinases , Masculino , Camundongos , Doença de Parkinson Secundária/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos Sprague-DawleyRESUMO
Insufficient local levels of neurotrophic factor after spinal cord injury (SCI) are the leading cause of secondary injury and limited axonal regeneration. Neuritin belongs to a family of neurotrophic factors that promote neurite outgrowth, maintain neuronal survival, and provide a favorable microenvironment for the regeneration and repair of nerve cells after injury. However, it is not known whether the exogenously applied neuritin protein has a positive effect on nerve repair after SCI. This was investigated in the present study using purified human recombinant neuritin expressed in and purified from Pichia pastoris, which was tested in a rat SCI model. A recombinant neuritin concentration of 60 µg/ml induced the recovery of hind limb motor function and stimulated nerve regeneration in rats with SCI. Continuous administration of neuritin at this dose at an early stage after SCI inhibited poly ADP ribose polymerase (PARP) protein degradation and decreased neuronal apoptosis. In addition, during the critical postinjury period of axonal regeneration, exogenous neuritin treatment increased the expression of neurofilament 200 and growth-associated protein 43 in the damaged tissue, which was associated with the restoration of hind limb movement. These results suggest that neuritin creates an environment that promotes nerve cell survival and neurite regeneration after SCI, which contribute to nerve regeneration and the recovery of motor function.
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Axônios/fisiologia , Vetores Genéticos/administração & dosagem , Regeneração Nervosa/efeitos dos fármacos , Neurônios/citologia , Neuropeptídeos/farmacologia , Traumatismos da Medula Espinal/fisiopatologia , Medula Espinal/citologia , Animais , Axônios/efeitos dos fármacos , Feminino , Proteínas Ligadas por GPI/farmacologia , Masculino , Neurônios/metabolismo , Ratos , Ratos Wistar , Recuperação de Função Fisiológica , Medula Espinal/metabolismoRESUMO
OBJECTIVE: To investigate the effects of Neuritin on the regeneration of the neural axons after acute spinal cord injury (SCI) in rats. METHODS: The model of acute SCI at T10 was established in 54 adult healthy Wistar rats (half males and half females) weighing 250-300 g by using the improved Allen's weight-drop method. The rats were randomly divided into 3 groups. 100 microL (6 microg) Neuritin and His protein was injected into group A (n = 24) and group B (n = 24), respectively, through subarachnoid catheter. Six rats from each group were killed 3, 7, 14, and 28 days after injury to receive Basso, Beattie and Bresnahan (BBB) locomotor rating scaling, HE staining observation, and immunohistochemistry staining observation for neurofilament 200 (NF-200) and growth associated protein 43 (GAP-43). Group C (n = 6) served as sham-operated group receiving laminectomy without spinal injury and with an empty catheter in the subarachnoid space and received the above observations 7 days after injury. RESULTS: BBB scale: after operation, the scale of groups A and B was increased over time; group A was significantly higher than group B from 14 days (P < 0.05); group C was higher than groups A and B at different time points after operation (P < 0.05). HE staining: in group C, the injured spinal tissue was normal after operation; from 7 days after operation, group A presented deeper-stained nissl body, less physaliferous cells, and more nerve synapses when compared with group B. NF-200 and GAP-43 immunohistochemistry observation: in group C, there was just little positive expression; while in groups A and B, positive expression of NF-200 and GAP-43 was evident in the spinal cord from 7 days after operation. Mean density integral absorbency (IA) value of NF-200 and GAP-43: group A was higher than group B at each time point (P < 0.05) and group C was lower than groups A and B at each time point (P < 0.05). CONCLUSION: Local application of exogenous Neuritin can promote the axonal regeneration after acute SCI in rats and the recovery of the locomotion function of hind-limbs in rats.