RESUMEN
BACKGROUND: Mobile devices have been used by many older adults and have the potential to assist individuals with subjective cognitive complaints (SCCs) in daily living tasks. Financial management is one of the most complex daily activity for older adults, as it is easily impaired in the prodromal stage of dementia and cognitive impairment. AIM: To investigate financial management ability among older adults from SCCs and mobile device proficiency. METHODS: A self-administered questionnaire was sent to 529 participants who were ≥ 65 years and regularly use mobile devices. Participants were divided into four groups based on SCC prevalence and scores of the Mobile Device Proficiency Questionnaire (MDPQ-16). Financial management abilities were compared between groups using the Process Analysis of Daily Activities for Dementia subscale. Regression model and crosstabulation table were used to investigate associations in detail. RESULTS: A significant difference in financial management ability was observed among the four groups (p < 0.001), with the dual impairment group showed significantly lower than the robust and SCC groups (p < 0.001). Educational history, sex, and MDPQ-16 score were significantly associated with participants' financial management ability (p ≤ 0.01). The proportion of participants who could use ATMs and electronic money independently was significantly lower among those with low proficiency in mobile devices (LPM), regardless of SCC (p < 0.05). CONCLUSION: The LPM group showed an impaired ability to manage their finances, particularly in situations where they would use information devices. Therefore, healthcare professionals should assess not only the SCC but also their proficiency with mobile devices to predict their impairment in activities of daily living.
Asunto(s)
Disfunción Cognitiva , Demencia , Administración Financiera , Humanos , Anciano , Vida Independiente , Estudios Transversales , Actividades Cotidianas , Disfunción Cognitiva/terapia , Disfunción Cognitiva/psicología , Computadoras de Mano , CogniciónRESUMEN
BACKGROUND: Phospholipase A2 (PLA2)-derived proinflammatory lipid mediators such as prostaglandin E2 (PGE2), leukotrienes B4 (LTB4), lysophosphatidylcholine (LPC), and free fatty acids (FFA) are implicated in spinal cord injury (SCI) pathologies. Reducing the levels of these injurious bioactive lipid mediators is reported to ameliorate SCI. However, the specific role of the group IVA isoform of PLA2 cytosolic PLA2 (cPLA2) in lumbar spinal canal stenosis (LSS) due to cauda equina compression (CEC) injury is not clear. In this study, we investigated the role of cPLA2 in a rat model of CEC using a non-toxic cPLA2-preferential inhibitor, arachidonyl trifluoromethyl ketone (ATK). METHODS: LSS was induced in adult female rats by CEC procedure using silicone blocks within the epidural spaces of L4 to L6 vertebrae. cPLA2 inhibitor ATK (7.5 mg/kg) was administered by oral gavage at 2 h following the CEC. cPLA2-derived injurious lipid mediators and the expression/activity of cPLA2, 5-lipoxygenase (5-LOX), and cyclooxygenase-2 (COX-2) were assessed. ATK-treated (CEC + ATK) were compared with vehicle-treated (CEC + VEH) animals in terms of myelin levels, pain threshold, and motor function. RESULTS: ATK treatment of CEC animals reduced the phosphorylation of cPLA2 (pcPLA2) determined by Western blot, improved locomotor function evaluated by rotarod task, and reduced pain threshold evaluated by mechanical hyperalgesia method. Levels of FFA and LPC, along with PGE2 and LTB4, were reduced in CEC + ATK compared with CEC + VEH group. However, ATK treatment reduced neither the activity/expression of 5-LOX nor the expression of COX-2 in CEC + VEH animals. Increased cPLA2 activity in the spinal cord from CEC + VEH animals correlated well with decreased spinal cord as well as cauda equina fiber myelin levels, which were restored after ATK treatment. CONCLUSION: The data indicate that cPLA2 activity plays a significant role in tissue injury and pain after LSS. Reducing the levels of proinflammatory and tissue damaging eicosanoids and the deleterious lipid mediator LPC shows therapeutic potential. ATK inhibits cPLA2 activity, thereby decreasing the levels of injurious lipid mediators, reducing pain, improving functional deficits, and conferring protection against LSS injury. Thus, it shows potential for preclinical evaluation in LSS.
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Ácidos Araquidónicos/administración & dosificación , Inhibidores Enzimáticos/administración & dosificación , Polirradiculopatía/tratamiento farmacológico , Administración Oral , Análisis de Varianza , Animales , Araquidonato 5-Lipooxigenasa/metabolismo , Ciclooxigenasa 2/metabolismo , Dinoprostona/metabolismo , Modelos Animales de Enfermedad , Ácidos Grasos/metabolismo , Femenino , Hiperalgesia/tratamiento farmacológico , Hiperalgesia/etiología , Leucotrieno B4/metabolismo , Locomoción/efectos de los fármacos , Lisofosfatidilcolinas/metabolismo , Nocicepción/efectos de los fármacos , Polirradiculopatía/complicaciones , Ratas , Ratas Sprague-DawleyRESUMEN
BACKGROUND: Stroke immediately sets into motion sustained excitotoxicity and calcium dysregulation, causing aberrant activity in neuronal nitric oxide synthase (nNOS) and an imbalance in the levels of nitric oxide (NO). Drugs targeting nNOS-originated toxicity may therefore reduce stroke-induced damage. Recently, we observed that a redox-modulating agent of the NO metabolome, S-nitrosoglutathione (GSNO), confers neurovascular protection by reducing the levels of peroxynitrite, a product of aberrant NOS activity. We therefore investigated whether GSNO-mediated neuroprotection and improved neurological functions depend on blocking nNOS/peroxynitrite-associated injurious mechanisms using a rat model of cerebral ischemia reperfusion (IR). RESULTS: IR increased the activity of nNOS, the levels of neuronal peroxynitrite and phosphorylation at Ser(1412) of nNOS. GSNO treatment of IR animals decreased IR-activated nNOS activity and neuronal peroxynitrite levels by reducing nNOS phosphorylation at Ser(1412). The Ser(1412) phosphorylation is associated with increased nNOS activity. Supporting the notion that nNOS activity and peroxynitrite are deleterious following IR, inhibition of nNOS by its inhibitor 7-nitroindazole or reducing peroxynitrite by its scavenger FeTPPS decreased IR injury. GSNO also decreased the activation of AMP Kinase (AMPK) and its upstream kinase LKB1, both of which were activated in IR brain. AMPK has been implicated in nNOS activation via Ser(1412) phosphorylation. To determine whether AMPK activation is deleterious in the acute phase of IR, we treated animals after IR with AICAR (an AMPK activator) and compound c (an AMPK inhibitor). While AICAR potentiated, compound c reduced the IR injury. CONCLUSIONS: Taken together, these results indicate an injurious nNOS/peroxynitrite/AMPK cycle following stroke, and GSNO treatment of IR inhibits this vicious cycle, resulting in neuroprotection and improved neurological function. GSNO is a natural component of the human body, and its exogenous administration to humans is not associated with any known side effects. Currently, the FDA-approved thrombolytic therapy suffers from a lack of neuronal protective activity. Because GSNO provides neuroprotection by ameliorating stroke's initial and causative injuries, it is a candidate of translational value for stroke therapy.
Asunto(s)
Adenilato Quinasa/metabolismo , Fármacos Neuroprotectores/farmacología , Óxido Nítrico Sintasa de Tipo I/metabolismo , Ácido Peroxinitroso/metabolismo , S-Nitrosoglutatión/farmacología , Accidente Cerebrovascular/tratamiento farmacológico , Quinasas de la Proteína-Quinasa Activada por el AMP , Animales , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Encéfalo/patología , Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patología , Modelos Animales de Enfermedad , Infarto de la Arteria Cerebral Media , Masculino , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Neuronas/patología , Óxido Nítrico Sintasa de Tipo I/antagonistas & inhibidores , Fosforilación/efectos de los fármacos , Proteínas Serina-Treonina Quinasas/metabolismo , Distribución Aleatoria , Ratas Sprague-Dawley , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/metabolismo , Daño por Reperfusión/patología , Accidente Cerebrovascular/metabolismo , Accidente Cerebrovascular/patologíaRESUMEN
Aquaporin-4 (AQP4) plays a role in the generation of post-ischemic edema. Pharmacological modulation of AQP4 function may thus provide a novel therapeutic strategy for the treatment of stroke, tumor-associated edema, epilepsy, traumatic brain injury, and other disorders of the central nervous system (CNS) associated with altered brain water balance. Edaravone, a free radical scavenger, is used for the treatment of acute ischemic stroke (AIS) in Japan. In this study, edaravone significantly reduced the infarct area and improved the neurological deficit scores at 24h after reperfusion in a rat transient focal ischemia model. Furthermore, edaravone markedly reduced AQP4 immunoreactivity and protein levels in the cerebral infarct area. In light of observations that edaravone specifically inhibited AQP4 in a rat transient focal ischemia model, we propose that edaravone might reduce cerebral edema through the inhibition of AQP4 expression following cerebral infarction.
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Antipirina/análogos & derivados , Acuaporina 4/antagonistas & inhibidores , Edema Encefálico/tratamiento farmacológico , Isquemia Encefálica/complicaciones , Depuradores de Radicales Libres/uso terapéutico , Animales , Antipirina/uso terapéutico , Edema Encefálico/etiología , Modelos Animales de Enfermedad , Edaravona , Masculino , RatasRESUMEN
High mobility group box-1 (HMGB1), a non-histone DNA-binding protein, is massively released into the extracellular space from neuronal cells after ischemic insult and exacerbates brain tissue damage in rats. Minocycline is a semisynthetic second-generation tetracycline antibiotic which has recently been shown to be a promising neuroprotective agent. In this study, we found that minocycline inhibited HMGB1 release in oxygen-glucose deprivation (OGD)-treated PC12 cells and triggered the activation of p38mitogen-activated protein kinase (MAPK) and extracellular signal-regulated kinases (ERK1/2). The ERK kinase (MEK)1/2 inhibitor U-0126 and p38MAPK inhibitor SB203580 blocked HMGB1 release in response to OGD. Furthermore, HMGB1 triggered cell death in a dose-dependent fashion. Minocycline significantly rescued HMGB1-induced cell death in a dose-dependent manner. In light of recent observations as well as the good safety profile of minocycline in humans, we propose that minocycline might play a potent neuroprotective role through the inhibition of HMGB1-induced neuronal cell death in cerebral infarction.
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Apoptosis/efectos de los fármacos , Proteína HMGB1/antagonistas & inhibidores , Isquemia/metabolismo , Minociclina/farmacología , Neuronas/efectos de los fármacos , Animales , Butadienos/farmacología , Bovinos , Inhibidores Enzimáticos/farmacología , Glucosa/metabolismo , Proteína HMGB1/metabolismo , Isquemia/enzimología , Isquemia/patología , Proteína Quinasa 1 Activada por Mitógenos/antagonistas & inhibidores , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/antagonistas & inhibidores , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Neuronas/metabolismo , Neuronas/patología , Nitrilos/farmacología , Oxígeno/metabolismo , Células PC12 , Ratas , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismoRESUMEN
Midkine (MK) is a growth factor implicated in the development and repair of various tissues, especially neural tissues. MK acts as a reparative neurotrophic factor in damaged peripheral nerves. A postulated role of MK in the degeneration and regeneration of sciatic nerves was explored by comparing wild-type (Mdk(+/+)) mice with MK-deficient (Mdk(-/-)) mice after freezing injury. In the Mdk(-/-) mice, a regenerative delay was observed, preceded by a decelerated Wallerian degeneration (WD). The relative wet weight of the soleus muscle slowly declined, and recovery was delayed compared with that in the Mdk(+/+) mice. In the regenerating nerve, unmyelinated axons were unevenly distributed, and some axons contained myelin-like, concentrically lamellated bodies. In the endplates of soleus muscles, nerve terminals containing synaptic vesicles disappeared in both mice. In Mdk(-/-) mice, the appearance of nerve terminals was delayed in synaptic vesicles of terminal buttons after injury. The recovery of evoked electromyogram was delayed in Mdk(-/-) mice compared with Mdk(+/+) mice. Our results suggested a delay in axonal degeneration and regeneration in Mdk(-/-) mice compared with Mdk(+/+) mice, and the delayed regeneration was associated with a delayed recovery of motor function. These findings show that a lack of MK following peripheral nerve injury is a critical factor in degeneration and regeneration, and manipulation of the supply of MK may offer interesting therapeutic options for the treatment of peripheral nerve damage.
Asunto(s)
Citocinas/fisiología , Regeneración Nerviosa/fisiología , Nervio Ciático/lesiones , Degeneración Walleriana/fisiopatología , Animales , Citocinas/deficiencia , Citocinas/genética , Electromiografía , Congelación , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Midkina , Placa Motora/ultraestructura , Músculo Esquelético/inervación , Músculo Esquelético/patología , Fibras Nerviosas Amielínicas/patología , Regeneración Nerviosa/genética , Recuperación de la Función , Nervio Ciático/metabolismo , Degeneración Walleriana/genéticaRESUMEN
Edaravone, a potent free radical scavenger, is clinically used for the treatment of cerebral infarction in Japan. Here, we examined the effects of edaravone on the dynamics of high-mobility group box-1 (HMGB1), which is a key mediator of ischemic-induced brain damage, during a 48-h postischemia/reperfusion period in rats and in oxygen-glucose-deprived (OGD) PC12 cells. HMGB1 immunoreactivity was observed in both the cytoplasm and the periphery of cells in the cerebral infarction area 2 h after reperfusion. Intravenous administration of 3 and 6 mg/kg edaravone significantly inhibited nuclear translocation and HMGB1 release in the penumbra area and caused a 26.5 +/- 10.4 and 43.8 +/- 0.5% reduction, respectively, of the total infarct area at 24 h after reperfusion. Moreover, edaravone also decreased plasma HMGB1 levels. In vitro, edaravone dose-dependently (1-10 microM) suppressed OGD- and H(2)O(2)-induced HMGB1 release in PC12 cells. Furthermore, edaravone (3-30 microM) blocked HMGB1-triggered apoptosis in PC12 cells. Our findings suggest a novel neuroprotective mechanism for edaravone that abrogates the release of HMGB1.
Asunto(s)
Antipirina/análogos & derivados , Infarto Cerebral/tratamiento farmacológico , Depuradores de Radicales Libres/farmacología , Proteína HMGB1/metabolismo , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Transporte Activo de Núcleo Celular/efectos de los fármacos , Animales , Antipirina/farmacología , Antipirina/uso terapéutico , Apoptosis/efectos de los fármacos , Butadienos/farmacología , Hipoxia de la Célula/efectos de los fármacos , Hipoxia de la Célula/fisiología , Núcleo Celular/metabolismo , Infarto Cerebral/metabolismo , Infarto Cerebral/patología , Cerebro/metabolismo , Cerebro/patología , Citocromos c/metabolismo , Citoplasma/efectos de los fármacos , Citoplasma/metabolismo , Edaravona , Inhibidores Enzimáticos/farmacología , Quinasas MAP Reguladas por Señal Extracelular/antagonistas & inhibidores , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Depuradores de Radicales Libres/uso terapéutico , Glucosa/deficiencia , Proteína HMGB1/sangre , Peróxido de Hidrógeno/farmacología , Masculino , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Nitrilos/farmacología , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/fisiología , Células PC12 , Ratas , Ratas Wistar , Proteínas S100/metabolismoRESUMEN
Midkine (MK) is a multifunctional cytokine and heparin-binding growth factor with neurotrophic activity. MK and its receptor were examined for up to 14 days in a chemically injured rat muscle regeneration process caused by the injection of bupivacaine using immunohistochemical and Western blot analysis. Although MK immunoreactivity was not detectable in the mature uninjured skeletal muscle, MK was strongly detected in the regenerating muscle cells. MK immunoreactivity was observed in the myoblast-like cells and myotubes, which were desmin-positive cells, whereas it was not detectable in the surviving normal muscle fibers. Most myotubes labeling for desmin showed MK immunoreactivity 5-7days after the injury. However, MK immunoreactivity was not detected 14 days after the injury. Immunoreactivity of low-density lipoprotein receptor-related protein (LRP), a cell membrane receptor of MK, was detected in the regenerating muscle cells, whereas it was not detected in the normal adult skeletal muscle and surviving muscle. These findings suggested that MK was involved. MK may have a role for differentiation during skeletal muscle regeneration and may be taken up in an autocrine fashion with LRP.
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Bupivacaína/administración & dosificación , Bupivacaína/farmacología , Citocinas/metabolismo , Glicoproteínas de Membrana/metabolismo , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/metabolismo , Receptores de Factores de Crecimiento/metabolismo , Regeneración , Animales , Citocinas/inmunología , Inmunohistoquímica , Inyecciones Intraperitoneales , Masculino , Midkina , Músculo Esquelético/citología , Ratas , Ratas WistarRESUMEN
Traumatic brain injury (TBI) derails nitric oxide (NO)-based anti-inflammatory and anti-excitotoxicity mechanisms. NO is consumed by superoxide to form peroxynitrite, leading to decreased NO bioavailability for S-nitrosoglutathione (GSNO) synthesis and regulation of neuroprotective pathways. Neuronal peroxynitrite is implicated in neuronal loss and functional deficits following TBI. Using a contusion mouse model of TBI, we investigated mechanisms for the opposed roles of GSNO versus peroxynitrite for neuroprotection and functional recovery. TBI was induced by controlled cortical impact (CCI) in adult male mice. GSNO treatment at 2h after CCI decreased the expression levels of phospho neuronal nitric oxide synthase (pnNOS), alpha II spectrin degraded products, and 3-NT, while also decreasing the activities of nNOS and calpains. Treatment of TBI with FeTPPS, a peroxynitrite scavenger, had effects similar to GSNO treatment. GSNO treatment of TBI also reduced neuronal degeneration and improved neurobehavioral function in a two-week TBI study. In a cell free system, SIN-1 (a peroxynitrite donor and 3-nitrotyrosinating agent) increased whereas GSNO (an S-nitrosylating agent) decreased calpain activity, and these activities were reversed by, respectively, FeTPPS and mercuric chloride, a cysteine-NO bond cleaving agent. These data indicate that peroxynitrite-mediated activation and GSNO-mediated inhibition of the deleterious nNOS/calpain system play critical roles in the pathobiology of neuronal protection and functional recovery in TBI disease. Given GSNO׳s safety record in other diseases, its neuroprotective efficacy and promotion of functional recovery in this TBI study make low-dose GSNO a potential candidate for preclinical evaluation.
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Lesiones Encefálicas/tratamiento farmacológico , Encéfalo/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Recuperación de la Función/efectos de los fármacos , S-Nitrosoglutatión/farmacología , Animales , Encéfalo/metabolismo , Encéfalo/patología , Lesiones Encefálicas/metabolismo , Lesiones Encefálicas/patología , Calpaína/metabolismo , Modelos Animales de Enfermedad , Masculino , Ratones Endogámicos C57BL , Actividad Motora/efectos de los fármacos , Neuronas/efectos de los fármacos , Neuronas/patología , Óxido Nítrico Sintasa de Tipo I/metabolismo , Ácido Peroxinitroso/metabolismo , Fosforilación/efectos de los fármacos , Distribución Aleatoria , Recuperación de la Función/fisiologíaRESUMEN
Osteoarthritis (OA) is a whole joint disease characterized by cartilage degradation, which causes pain and disability in older adults. Our previous work showed that growth arrest and DNA damage-inducible protein 45 ß (GADD45ß) is upregulated in chondrocyte clusters in OA cartilage, especially in the early stage of this disease. CCAAT/enhancer binding protein ß (C/EBPß) is expressed in the hypertrophic growth plate chondrocytes and functions in synergy with GADD45ß. Here, the presence and localization of these proteins was assessed by immunohistochemistry using articular cartilage from OA patients, revealing colocalization of C/EBPß and GADD45ß in OA chondrocytes. GADD45ß promoter analysis was performed to determine whether C/EBPß directly regulates GADD45ß transcription. Furthermore, we analyzed the effect of C/EBPß on Gadd45ß gene regulation in articular chondrocytes in vivo and in vitro. Immunohistochemical analysis of C/ebpß-haploinsufficient mice (C/ebpß(+/-)) cartilage showed that C/ebpß haploinsufficiency led to reduced Gadd45ß gene expression in these cells. In vitro, we evaluated the effects of conditional C/EBPß overexpression driven by the cartilage oligomeric matrix protein (Comp) promoter in mComp-tTA;pTRE-Tight-BI-DsRed-mC/ebpß transgenic mice. C/EBPß overexpression significantly stimulated Gadd45ß gene expression in articular chondrocytes. Taken together, our data demonstrate that C/EBPß plays a central role in controlling Gadd45ß gene expression in these cells.
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Proteína beta Potenciadora de Unión a CCAAT/metabolismo , Proteínas de Ciclo Celular/biosíntesis , Condrocitos/metabolismo , Regulación de la Expresión Génica/fisiología , Proteínas Nucleares/biosíntesis , Osteoartritis/metabolismo , Anciano , Animales , Western Blotting , Proteína beta Potenciadora de Unión a CCAAT/genética , Cartílago Articular/metabolismo , Proteínas de Ciclo Celular/genética , Femenino , Humanos , Inmunohistoquímica , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Persona de Mediana Edad , Proteínas Nucleares/genética , Osteoartritis/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Transcripción GenéticaRESUMEN
BACKGROUND: For stroke patients, stimulating neurorepair mechanisms is necessary to reduce morbidity and disability. Our previous studies on brain and spinal cord trauma show that exogenous treatment with the S-nitrosylating agent S-nitrosoglutathione (GSNO) - a nitric oxide and glutathione metabolite of the human body - stimulates neurorepair and aids functional recovery. Using a rat model of cerebral ischemia and reperfusion (IR) in this study, we tested the hypothesis that GSNO invokes the neurorepair process and improves neurobehavioral functions through the angiogenic HIF-1α/VEGF pathway. METHODS: Stroke was induced by middle cerebral artery occlusion for 60 minutes followed by reperfusion in adult male rats. The injured animals were treated with saline (IR group, n=7), GSNO (0.25 mg/kg, GSNO group, n=7), and GSNO plus the HIF-1α inhibitor 2-methoxyestra-diol (2-ME) (0.25 mg/kg GSNO + 5.0 mg/kg 2-ME, GSNO + 2-ME group, n=7). The groups were studied for either 7 or 14 days to determine neurorepair mediators and functional recovery. Brain capillary endothelial cells were used to show that GSNO promotes angiogenesis and that GSNO-mediated induction of VEGF and the stimulation of angiogenesis are dependent on HIF-1α activity. RESULTS: IR injury increased the expression of neurorepair mediators HIF-1α, VEGF, and PECAM-1 and vessel markers to a limited degree that correlate well with significantly compromised neurobehavioral functions compared with sham animals. GSNO treatment of IR not only remarkably enhanced further the expression of HIF-1α, VEGF, and PECAM-1 but also improved functioning compared with IR. The GSNO group also had a higher degree of vessel density than the IR group. Increased expression of VEGF and the degree of tube formation (angiogenesis) by GSNO were reduced after the inhibition of HIF-1α by 2-ME in an endothelial cell culture model. 2-ME treatment of the GSNO group also blocked not only GSNO's effect of reduced infarct volume, decreased neuronal loss, and enhanced expression of PECAM-1 (P<0.001), but also its improvement of motor and neurological functions (P<0.001). CONCLUSION: GSNO stimulates the process of neurorepair, promotes angiogenesis, and aids functional recovery through the HIF-1α-dependent pathway, showing therapeutic and translational promise for stroke.
Asunto(s)
Endotelio Vascular/efectos de los fármacos , Subunidad alfa del Factor 1 Inducible por Hipoxia/efectos de los fármacos , Regeneración Nerviosa/efectos de los fármacos , S-Nitrosoglutatión/farmacología , Transducción de Señal/efectos de los fármacos , Accidente Cerebrovascular/tratamiento farmacológico , Factor A de Crecimiento Endotelial Vascular/efectos de los fármacos , Vasodilatadores/farmacología , Animales , Conducta Animal/efectos de los fármacos , Isquemia Encefálica/patología , Línea Celular , Proliferación Celular/efectos de los fármacos , Masculino , Arteria Cerebral Media/patología , Actividad Motora/efectos de los fármacos , Neovascularización Fisiológica/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Recuperación de la Función , Accidente Cerebrovascular/psicologíaRESUMEN
Midkine (MK), a heparin-binding growth factor, was previously found to be expressed in the rat myotube-forming stage. We investigated MK gene-deficient (Mdk(-/-)) mice in terms of skeletal muscle degeneration and regeneration after injury by bupivacaine injection into the tibialis anterior muscle. Injured muscles showed intense inflammatory cell infiltration. Myotubes, myofibers with centrally located nuclei in their cytoplasm, were significantly smaller in Mdk(-/-) mice than in wild type (Mdk(+/+)) mice 7 days after injury (p=0.02). The distribution of myotube sizes showed quantitative differences between the two groups at 5 and 7 days, but not at 14 days. Many small myotubes were found in the regenerative area of Mdk(-/-) mice compared with that of Mdk(+/+)mice 5 and 7 days after injury. The expression of Iba1, a macrophage marker, was significantly lower in Mdk(-/-) mice 3 days after injury (p=0.01). The number of desmin-positive cells like myoblasts in Mdk(-/-) mice was significantly fewer than that in Mdk(+/+) mice 3 days after injury. Our results suggested that deletion of MK results in a delay in regeneration, preceded by decelerated migration of macrophages to the damaged area, and that MK has a role in cell differentiation and maturation after skeletal muscle injury.
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Músculo Esquelético/lesiones , Músculo Esquelético/fisiología , Factores de Crecimiento Nervioso/genética , Factores de Crecimiento Nervioso/metabolismo , Regeneración/fisiología , Animales , Células Cultivadas , Inmunohistoquímica , Ratones , Midkina , Músculo Esquelético/metabolismo , Factores de Crecimiento Nervioso/ultraestructura , Ratas , Factores de TiempoRESUMEN
UNLABELLED: Midkine (MK) is a growth factor with neurotrophic and neurite outgrowth activities. It was expressed in the peri-ischaemic area in the acute phase of cerebral infarction in rat brains. Astrocytes were the origin of MK in this occasion. MK has been assessed in terms of its effects on neural injury. The administration of MK into the lateral ventricle immediately prior to ischaemia prevented cell death in the hippocampal CA1 neurons degenerated by transient forebrain ischaemia in gerbils. MK administration was also beneficial in rats with neural injury, especially after kainic acid-induced seizures. Gene therapy with mouse MK cDNA using an adenovirus was effective in reducing the cerebral infarction volume and in increasing the number of neuronal precursor cells in the subventricular zone of the rat brain. MK mRNA and MK protein were found in spinal cord motor neurons of the anterior horn in both the acute phase of sciatic nerve injury and 3 weeks later. MK immunoreactivity was also found in the proximal side of a sciatic nerve-injured site in sciatic nerve axons. MK receptors were expressed in Schwann cells after injury, suggesting crosstalk between axons and Schwann cells. MK was also present in nerve terminals and influenced ACh receptor clustering during neuromuscular development in Xenopus. Thus, MK may also be involved in reinforcing and maintaining the synapse. All these findings indicate the therapeutic potential of MK for promoting repair of the nervous system after injury. LINKED ARTICLES: This article is part of a themed section on Midkine. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2014.171.issue-4.
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Lesiones Encefálicas/metabolismo , Citocinas/metabolismo , Factores de Crecimiento Nervioso/metabolismo , Nervio Ciático/metabolismo , Animales , Humanos , Midkina , Nervio Ciático/lesionesRESUMEN
Most patients with thoracic ossification of the posterior longitudinal ligament (OPLL) exhibit delayed recovery of gait dysfunction after spinal injury. The hybrid assistive limb (HAL) is a new robot suit controlling knee and hip joint motion by detecting very weak bioelectric signals on the surface of the skin. This study is to report the feasibility and benefits of patient-assistive HAL walking rehabilitation for facilitating locomotor function after spinal surgery. The patient was a 60-year-old woman with thoracic OPLL, and her motor and sensory paralyses did not improve after spinal surgery, indicating severe impairment in the paretic legs. The subject underwent 6 HAL sessions per week for 8 weeks, consisting of a standing and sitting exercise and walking on the ground with HAL. Clinical outcomes were evaluated before and after HAL training and 1 year after surgery. The subject improved considerably as a result of HAL training. Subsequently, her walking ability recovered rapidly, and she was able to walk unaided six months after surgery. This case study suggests that HAL training is a feasible and effective option to facilitating locomotor function and the early HAL training with physiotherapy may enhance motor recovery of patients with residual paralysis after surgery.
RESUMEN
Intracellular accumulation of altered proteins, including p62 and ubiquitinated proteins, is the basis of most neurodegenerative disorders. The relationship among the accumulation of altered proteins, autophagy, and spinal cord dysfunction by cervical spondylotic myelopathy has not been clarified. We examined the expression of p62 and autophagy markers in the chronically compressed spinal cord of tiptoe-walking Yoshimura mice. In addition, we examined the expression and roles of p62 and autophagy in hypoxic neuronal cells. Western blot analysis showed the accumulation of p62, ubiquitinated proteins, and microtubule-associated protein 1 light chain 3 (LC3), an autophagic marker, in the compressed spinal cord. Immunohistochemical examinations showed that p62 accumulated in neurons, axons, astrocytes, and oligodendrocytes. Electron microscopy showed the expression of autophagy markers, including autolysosomes and autophagic vesicles, in the compressed spinal cord. These findings suggest the presence of p62 and autophagy in the degenerated compressed spinal cord. Hypoxic stress increased the expression of p62, ubiquitinated proteins, and LC3-II in neuronal cells. In addition, LC3 turnover assay and GFP-LC3 cleavage assay showed that hypoxic stress increased autophagy flux in neuronal cells. These findings suggest that hypoxic stress induces accumulation of p62 and autophagy in neuronal cells. The forced expression of p62 decreased the number of neuronal cells under hypoxic stress. These findings suggest that p62 accumulation under hypoxic stress promotes neuronal cell death. Treatment with 3-methyladenine, an autophagy inhibitor decreased the number of neuronal cells, whereas lithium chloride, an autophagy inducer increased the number of cells under hypoxic stress. These findings suggest that autophagy promotes neuronal cell survival under hypoxic stress. Our findings suggest that pharmacological inducers of autophagy may be useful for treating cervical spondylotic myelopathy patients.
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Proteínas Adaptadoras Transductoras de Señales/metabolismo , Autofagia , Proteínas de Choque Térmico/metabolismo , Degeneración Nerviosa/patología , Neuronas/patología , Compresión de la Médula Espinal/patología , Médula Espinal/patología , Estrés Mecánico , Animales , Astrocitos/metabolismo , Astrocitos/patología , Axones/metabolismo , Axones/patología , Recuento de Células , Hipoxia de la Célula , Proliferación Celular , Vértebras Cervicales/patología , Vértebras Cervicales/ultraestructura , Lisosomas/metabolismo , Ratones , Proteínas Asociadas a Microtúbulos/metabolismo , Degeneración Nerviosa/complicaciones , Degeneración Nerviosa/metabolismo , Neuronas/metabolismo , Oligodendroglía/metabolismo , Oligodendroglía/patología , Fagosomas/metabolismo , Proteína Sequestosoma-1 , Médula Espinal/metabolismo , Médula Espinal/ultraestructura , Compresión de la Médula Espinal/complicaciones , Compresión de la Médula Espinal/metabolismo , Estrés Fisiológico , Proteínas Ubiquitinadas/metabolismo , Regulación hacia ArribaRESUMEN
Growth arrest and DNA damage-inducible protein 45ß (GADD45ß) is expressed in normal and early osteoarthritic articular cartilage. We recently reported that GADD45ß enhances CCAAT/enhancer binding protein ß (C/EBPß) activation in vitro. This study was undertaken in order to determine whether GADD45ß is expressed with C/EBPß in aging articular cartilage. We also investigated whether the synergistic expression of GADD45ß and C/EBPß may be involved in the mechanism of chondrocyte senescence. Senescence-accelerated mice (SAMP1) were used as a model of aging. GADD45ß, C/EBPß, and p21 were analyzed by immunohistochemistry. A luciferase reporter assay using ATDC5 cells was performed in order to examine p21 as a target gene of the GADD45ß/C/EBPß cascade. GADD45ß exhibited increased expression in the aging articular cartilage of SAMP1 mice compared to that in control mice. The co-localization of GADD45ß and C/EBPß was confirmed by double immunostaining. The synergistic mechanisms of GADD45ß and C/EBPß on the gene regulation of p21, a molecule related to cellular senescence, were verified by a p21-luciferase reporter assay. Co-expression of C/EBPß and p21 was confirmed. These observations suggest that the synergism between GADD45ß and C/EBPß may play an important role in cellular senescence in the aging articular cartilage.
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Envejecimiento/metabolismo , Antígenos de Diferenciación/metabolismo , Proteína beta Potenciadora de Unión a CCAAT/metabolismo , Cartílago Articular/fisiología , Condrocitos/fisiología , Quinasas p21 Activadas/genética , Envejecimiento/genética , Animales , Antígenos de Diferenciación/genética , Proteína beta Potenciadora de Unión a CCAAT/genética , Cartílago Articular/citología , Línea Celular , Senescencia Celular/genética , Senescencia Celular/fisiología , Condrocitos/citología , Daño del ADN , Regulación Enzimológica de la Expresión Génica , Luciferasas , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Modelos Animales , Osteoartritis/genética , Osteoartritis/fisiopatología , Regiones Promotoras Genéticas , Transducción de Señal , Quinasas p21 Activadas/metabolismoRESUMEN
Edaravone was originally developed as a potent free radical scavenger and has been widely used to treat cerebral infarction in Japan since 2001. Several free radical scavengers have been developed and some of them have progressed to clinical trials for the treatment of cerebral infarction. One such scavenger, edaravone, has been approved by the regulatory authority in Japan for the treatment of patients with cerebral infarction. Of particular interest is the ability of edaravone to diffuse into the central nervous system in various neurologic diseases. Aside from its hydroxyl radical scavenging effect, edaravone has been found to have beneficial effects on inflammation, matrix metalloproteinases, nitric oxide production and apoptotic cell death. Concordantly, edaravone has been found to have neuroprotective effects in a number of animal models of disease, including stroke, spinal cord injury, traumatic brain injury, neurodegenerative diseases and brain tumors. The proven safety of edaravone following 9 years of use as a free radical scavenger suggests that it may have potential for development into an effective treatment of multiple neurologic conditions in humans.
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Acute stroke, including acute ischemic stroke (AIS) and acute hemorrhagic stroke, (AHS) is a common medical problem with particular relevance to the demographic changes in industrialized societies. In recent years, treatments for AIS have emerged, including thrombolysis with tissue plasminogen activator (t-PA). Although t-PA is the most effective currently available therapy, it is limited by a narrow therapeutic time window and side effects, and only 3% of all AIS patients receive thrombolysis. Edaravone was originally developed as a potent free radical scavenger and, since 2001, has been widely used to treat AIS in Japan. It was shown that edaravone extended the narrow therapeutic time window of t-PA in rats. The therapeutic time window is very important for the treatment of AIS, and early edaravone treatment is more effective. Thus, more AIS patients might be rescued by administering edaravone with t-PA. Meanwhile, edaravone attenuates AHS-induced brain edema, neurologic deficits and oxidative injury in rats. Although edaravone treatment is currently only indicated for AIS, it does offer neuroprotective effects against AHS in rats. Therefore, we hypothesize that early administration of edaravone can rescue AHS patients as well as AIS patients. Taken together, our findings suggest that edaravone should be immediately administered on suspicion of acute stroke, including AIS and AHS.
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Antipirina/análogos & derivados , Depuradores de Radicales Libres/uso terapéutico , Fármacos Neuroprotectores/uso terapéutico , Accidente Cerebrovascular/tratamiento farmacológico , Animales , Antipirina/uso terapéutico , Edaravona , Humanos , Ratas , Activador de Tejido Plasminógeno/uso terapéuticoRESUMEN
Estimation of the postmortem interval (PMI) is one of the most important tasks in forensic medicine. Numerous methods have been proposed for the determination of the time since death by chemical means. High mobility group box-1 (HMGB1), a nonhistone DNA-binding protein is released by eukaryotic cells upon necrosis. Postmortem serum levels of HMGB1 of 90 male Wistar rats stored at 4, 14 and 24°C since death were measured by enzyme-linked immunosorbent assay. The serum HMGB1 level showed a time-dependent increase up to seven days at 4°C. At 14°C, the HMGB1 level peaked at day 3, decreased at day 4, and then plateaued. At 24°C, the HMGB1 level peaked at day 2, decreased at day 3, and then plateaued. Our findings suggest that HMGB1 is related to the PMI in rats.
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OBJECTIVE: This study was to clarify the roles of midkine (MK) in the brain. METHODS: We determined cerebrospinal fluid MK levels in patients with neurological disorders by enzyme-linked immunoassay and immunostained autopsied brain samples in patients with meningitis. RESULTS: MK levels were 0.37+/-0.21 ng/ml in controls (n=46, mean +/- S.D.), 0.67+/-0.19 ng/ml in patients with cerebral infarction (n=8), 1.78+/-1.32 ng/ml in patients with meningitis (n=25; ANOVA and post-hoc Fisher's PLSD test, p<0.0001), 0.31+/-0.25 ng/ml in patients with human T-lymphotrophic virus type I-associated myelopathy/tropical spastic paraparesis (n=29), and 0.42+/-0.17 ng/ml in patients with amyotrophic lateral sclerosis (n=8). The regression equations were Y=0.005X+0.498 (Y, CSF MK level; X, cell number) and Y=0.007X+0.326 (Y, MK level; X, protein level) for all CSF samples. Autopsy brain samples from patients with meningitis expressed MK weakly in mononuclear cells on immunohistochemical examination. Western blot and polymerase chain reaction analyses showed that leukocytes were MK positive. CSF MK levels were not high in patients with cerebral infarction but were increased in patients with meningitis. CSF MK levels were high in normal controls, compared to those of other cytokines. MK was expressed in choroid plexus of normal brain and released there. CONCLUSION: Our findings suggested that MK may maintain normal adult brain as a neurotrophic factor, and that MK may be released from leucocytes in brain of patients with meningitis as an immunological mediator.