RESUMEN
Ischemic stroke can lead to systemic inflammation, which can activate peripheral immune cells, causing neuroinflammation and brain injury. Meningeal lymphatics play a crucial role in transporting solutes and immune cells out of the brain and draining them into cervical lymph nodes (CLNs). However, the role of meningeal lymphatics in regulating systemic inflammation during the reperfusion stage after ischemia is not well understood. In this study, we demonstrated that brain infarct size, neuronal loss, and the effector function of inflammatory macrophage subsets were reduced after ischemia-reperfusion and disruption of meningeal lymphatics. Spatial memory function was improved in the late stage of ischemic stroke following meningeal lymphatic disruption. Brain-infiltrating immune cells, including neutrophils, monocytes, and T and natural killer cells, were reduced after cerebral ischemia-reperfusion and meningeal lymphatic disruption. Single-cell RNA sequencing analysis revealed that meningeal lymphatic disruption reprogrammed the transcriptome profile related to chemotaxis and leukocyte migration in CLN lymphatic endothelial cells (LECs), and it also decreased chemotactic CCN1 expression in floor LECs. Replenishment of CCN1 through intraventricular injection increased brain infarct size and neuronal loss, while restoring numbers of macrophages/microglia in the brains of meningeal lymphatic-disrupted mice after ischemic stroke. Blocking CCN1 in cerebrospinal fluid reduced brain infarcts and improves spatial memory function after ischemia-reperfusion injury. In summary, this study indicates that CCN1-mediated detrimental inflammation was alleviated after cerebral ischemia-reperfusion injury and meningeal lymphatic disruption. CCN1 represents a novel therapeutic target for inhibiting systemic inflammation in the brain-CLN axis after ischemia-reperfusion injury.
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Stroke is a major cause of death and disability across the world, and its detrimental impact should not be underestimated. Therapies are available and effective for ischemic stroke (e.g., thrombolytic recanalization and mechanical thrombectomy); however, there are limitations to therapeutic interventions. Recanalization therapy has developed dramatically, while the use of adjunct neuroprotective agents as complementary therapies remains deficient. Pathological TAR DNA-binding protein (TDP-43) has been identified as a major component of insoluble aggregates in numerous neurodegenerative pathologies, including ALS, FTLD and Alzheimer's disease. Here, we show that increased pathological TDP-43 fractions accompanied by impaired mitochondrial function and increased gliosis were observed in an ischemic stroke rat model, suggesting a pathological role of TDP-43 in ischemic stroke. In ischemic rats administered rapamycin, the insoluble TDP-43 fraction was significantly decreased in the ischemic cortex region, accompanied by a recovery of mitochondrial function, the attenuation of cellular apoptosis, a reduction in infarct areas and improvements in motor defects. Accordingly, our results suggest that rapamycin provides neuroprotective benefits not only by ameliorating pathological TDP-43 levels, but also by reversing mitochondrial function and attenuating cell apoptosis in ischemic stroke.
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Esclerosis Amiotrófica Lateral , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Animales , Ratas , Sirolimus/farmacología , Sirolimus/uso terapéutico , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Accidente Cerebrovascular/tratamiento farmacológico , Apoptosis , Esclerosis Amiotrófica Lateral/patologíaRESUMEN
Maternal immune activation (MIA) increases the risk of autism spectrum disorder (ASD) in offspring. Microbial dysbiosis is associated with ASD symptoms. However, the alterations in the brain-gut-microbiota axis in lipopolysaccharide (LPS)-induced MIA offspring remain unclear. Here, we examined the social behavior, anxiety-like and repetitive behavior, microbiota profile, and myelination levels in LPS-induced MIA rat offspring. Compared with control offspring, MIA male rat offspring spent less time in an active social interaction with stranger rats, displayed more anxiety-like and repetitive behavior, and had more hypomyelination in the prefrontal cortex and thalamic nucleus. A fecal microbiota analysis revealed that MIA offspring had a higher abundance of Alistipes, Fusobacterium, and Ruminococcus and a lower abundance of Coprococcus, Erysipelotrichaies, and Actinobacteria than control offspring, which is consistent with that of humans with ASD. The least absolute shrinkage and selection operator (LASSO) method was applied to determine the relative importance of the microbiota, which indicated that the abundance of Alistipes and Actinobacteria was the most relevant for the profile of defective social behavior, whereas Fusobacterium and Coprococcus was associated with anxiety-like and repetitive behavior. In summary, LPS-induced MIA offspring showed an abnormal brain-gut-microbiota axis with social behavior deficits, anxiety-like and repetitive behavior, hypomyelination, and an ASD-like microbiota profile.
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BACKGROUND: Stroke is one of the leading causes of death and disability worldwide and places a heavy burden on the economy in our society. Current treatments, such as the use of thrombolytic agents, are often limited by a narrow therapeutic time window. However, the regeneration of the brain after damage is still active days, even weeks, after stroke occurs, which might provide a second window for treatment. Emodin, a traditional Chinese medicinal herb widely used to treat acute hepatitis, has been reported to possess antioxidative capabilities and protective effects against myocardial ischemia/reperfusion injury. However, the underlying mechanisms and neuroprotective functions of Emodin in a rat middle cerebral artery occlusion (MCAO) model of ischemic stroke remain unknown. This study investigates neuroprotective effects of Emodin in ischemia both in vitro and in vivo. METHODS: PC12 cells were exposed to oxygen-glucose deprivation to simulate hypoxic injury, and the involved signaling pathways and results of Emodin treatment were evaluated. The therapeutic effects of Emodin in ischemia animals were further investigated. RESULTS: Emodin reduced infarct volume and cell death following focal cerebral ischemia injury. Emodin treatment restored PC12 cell viability and reduced reactive oxygen species (ROS) production and glutamate release under conditions of ischemia/hypoxia. Emodin increased Bcl-2 and glutamate transporter-1 (GLT-l) expression but suppressed activated-caspase 3 levels through activating the extracellular signal-regulated kinase (ERK)-1/2 signaling pathway. CONCLUSION: Emodin induced Bcl-2 and GLT-1 expression to inhibit neuronal apoptosis and ROS generation while reducing glutamate toxicity via the ERK-1/2 signaling pathway. Furthermore, Emodin alleviated nerve cell injury following ischemia/reperfusion in a rat MCAO model. Emodin has neuroprotective effects against ischemia/reperfusion injury both in vitro and in vivo, which may be through activating the ERK-1/2 signaling pathway.
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Emodina/farmacología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Daño por Reperfusión/etiología , Daño por Reperfusión/metabolismo , Animales , Biomarcadores , Supervivencia Celular , Susceptibilidad a Enfermedades , Hipoxia/metabolismo , Inmunohistoquímica , Células PC12 , Ratas , Daño por Reperfusión/tratamiento farmacológicoRESUMEN
Although a good deal is known about the genetics and pathophysiology of Parkinson's disease (PD), and information is emerging about its cause, there are no pharmacological treatments shown to have a significant, sustained capacity to prevent or attenuate the ongoing neurodegenerative processes. However, there is accumulating clinical results to suggest that physical exercise is such a treatment, and studies of animal models of the dopamine (DA) deficiency associated with the motor symptoms of PD further support this hypothesis. Exercise is a non-pharmacological, economically practical, and sustainable intervention with little or no risk and with significant additional health benefits. In this study, we investigated the long-term effects of voluntary exercise on motor behavior and brain biochemistry in the transgenic MitoPark mouse PD model with progressive degeneration of the DA systems caused by DAT-driven deletion of the mitochondrial transcription factor TFAM in DA neurons. We found that voluntary exercise markedly improved behavioral function, including overall motor activity, narrow beam walking, and rotarod performance. There was also improvement of biochemical markers of nigrostriatal DA input. This was manifested by increased levels of DA measured by HPLC, and of the DA membrane transporter measured by PET. Moreover, exercise increased oxygen consumption and, by inference, ATP production via oxidative phosphorylation. Thus, exercise augmented aerobic mitochondrial oxidative metabolism vs glycolysis in the nigrostriatal system. We conclude that there are clear-cut physiological mechanisms for beneficial effects of exercise in PD.
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Enfermedad de Parkinson/metabolismo , Esfuerzo Físico/fisiología , Animales , Biomarcadores/metabolismo , Cuerpo Estriado/efectos de los fármacos , Proteínas de Unión al ADN/metabolismo , Modelos Animales de Enfermedad , Dopamina/metabolismo , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/metabolismo , Neuronas Dopaminérgicas/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Mitocondrias/metabolismo , Actividad Motora/fisiología , Enfermedad de Parkinson/terapia , Sustancia Negra/efectos de los fármacos , Factores de Transcripción/metabolismo , Tirosina 3-Monooxigenasa/metabolismoRESUMEN
Stroke is a leading cause of death and severe disability worldwide. After cerebral ischemia, inflammation plays a central role in the development of permanent neurological damage. Reactive oxygen species (ROS) are involved in the mechanism of post-ischemic inflammation. The activation of several inflammatory enzymes produces ROS, which subsequently suppress mitochondrial activity, leading to further tissue damage. Pomalidomide (POM) is a clinically available immunomodulatory and anti-inflammatory agent. Prior cellular studies demonstrate that POM can mitigate oxidative stress and lower levels of pro-inflammatory cytokines, particularly TNF-α, which plays a prominent role in ischemic stroke-induced brain damage and functional deficits. To evaluate the potential value of POM in cerebral ischemia, POM was initially administered to transgenic mice chronically over-expressing TNF-α surfactant protein (SP)-C promoter (SP-C/TNF-α mice) to assess whether systemically administered drug could lower systemic TNF-α level. POM significantly lowered serum levels of TNF-α and IL-5. Pharmacokinetic studies were then undertaken in mice to evaluate brain POM levels following systemic drug administration. POM possessed a brain/plasma concentration ratio of 0.71. Finally, rats were subjected to transient middle cerebral artery occlusion (MCAo) for 60 min, and subsequently treated with POM 30 min thereafter to evaluate action on cerebral ischemia. POM reduced the cerebral infarct volume in MCAo-challenged rats and improved motor activity, as evaluated by the elevated body swing test. POM's neuroprotective actions on ischemic injury represent a potential therapeutic approach for ischemic brain damage and related disorders, and warrant further evaluation.
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Inhibidores de la Angiogénesis/uso terapéutico , Isquemia Encefálica/tratamiento farmacológico , Talidomida/análogos & derivados , Inhibidores de la Angiogénesis/farmacología , Animales , Masculino , Ratones , Ratas , Talidomida/farmacología , Talidomida/uso terapéuticoRESUMEN
Mild traumatic brain injury (mTBI) constitutes 75 â¼ 90% of all TBI cases and causes various physical, cognitive, emotional, and other psychological symptoms. Nogo receptor 1 (NgR1) is a regulator of structural brain plasticity during development and in adulthood. Here, we used mice that, in the absence of doxycycline, overexpress NgR1 in forebrain neurons (MemoFlex) to determine the role of NgR1 in recovery from mTBI with respect to balance, cognition, memory, and emotion. We compared wild-type (WT), MemoFlex, and MemoFlex + doxycycline mice to the same three groups subjected to mTBI. mTBI was induced by a controlled 30-g weight drop. We found that inability to downregulate NgR1 significantly impairs recovery from mTBI-induced impairments. When the NgR1 transgene was turned off, recovery was similar to that of WT mice. The results suggest that the ability to regulate NgR1 signaling is needed for optimal recovery of motor coordination and balance, spatial memory, cognition, and emotional functions after mTBI.
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Conmoción Encefálica/metabolismo , Cognición/fisiología , Emociones/fisiología , Receptor Nogo 1/metabolismo , Equilibrio Postural/fisiología , Recuperación de la Función/fisiología , Animales , Conmoción Encefálica/fisiopatología , Modelos Animales de Enfermedad , Femenino , Masculino , Ratones , Ratones Transgénicos , Neuronas/metabolismo , Receptor Nogo 1/genética , Prosencéfalo/metabolismo , Memoria Espacial/fisiologíaRESUMEN
Due to its high oxygen demand and abundance of peroxidation-susceptible lipid cells, the brain is particularly vulnerable to oxidative stress. Induced by a redox state imbalance involving either excessive generation of reactive oxygen species (ROS) or dysfunction of the antioxidant system, oxidative stress plays a central role in a common pathophysiology that underpins neuronal cell death in acute neurological disorders epitomized by stroke and chronic ones such as Alzheimer's disease. After cerebral ischemia, for example, inflammation bears a key responsibility in the development of permanent neurological damage. ROS are involved in the mechanism of post-ischemic inflammation. The activation of several inflammatory enzymes produces ROS, which subsequently suppress mitochondrial activity, leading to further tissue damage. Pomalidomide (POM) is a clinically available immunomodulatory and anti-inflammatory agent. Using H2O2-treated rat primary cortical neuronal cultures, we found POM displayed neuroprotective effects against oxidative stress and cell death that associated with changes in the nuclear factor erythroid derived 2/superoxide dismutase 2/catalase signaling pathway. POM also suppressed nuclear factor kappa-light-chain-enhancer (NF-κB) levels and significantly mitigated cortical neuronal apoptosis by regulating Bax, Cytochrome c and Poly (ADP-ribose) polymerase. In summary, POM exerted neuroprotective effects via its anti-oxidative and anti-inflammatory actions against H2O2-induced injury. POM consequently represents a potential therapeutic agent against brain damage and related disorders and warrants further evaluation.
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Antioxidantes/farmacología , Apoptosis , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Talidomida/análogos & derivados , Animales , Células Cultivadas , Corteza Cerebral/citología , Peróxido de Hidrógeno/toxicidad , Neuronas/metabolismo , Estrés Oxidativo , Ratas , Ratas Sprague-Dawley , Talidomida/farmacologíaRESUMEN
In the present study, the effectiveness of glucose-dependent insulinotropic polypeptide (GIP) was evaluated by behavioral tests in 6-hydroxydopamine (6-OHDA) hemi-parkinsonian (PD) rats. Pharmacokinetic measurements of GIP were carried out at the same dose studied behaviorally, as well as at a lower dose used previously. GIP was delivered by subcutaneous administration (s.c.) using implanted ALZET micro-osmotic pumps. After two days of pre-treatment, male Sprague Dawley rats received a single unilateral injection of 6-OHDA into the medial forebrain bundle (MFB). The neuroprotective effects of GIP were evaluated by apomorphine-induced contralateral rotations, as well as by locomotor and anxiety-like behaviors in open-field tests. Concentrations of human active and total GIP were measured in plasma during a five-day treatment period by ELISA and were found to be within a clinically translatable range. GIP pretreatment reduced behavioral abnormalities induced by the unilateral nigrostriatal dopamine (DA) lesion produced by 6-OHDA, and thus may be a novel target for PD therapeutic development.
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Antiparkinsonianos/uso terapéutico , Incretinas/uso terapéutico , Trastornos Parkinsonianos/tratamiento farmacológico , Animales , Antiparkinsonianos/administración & dosificación , Incretinas/administración & dosificación , Locomoción , Masculino , Oxidopamina/toxicidad , Trastornos Parkinsonianos/etiología , Ratas , Ratas Sprague-DawleyRESUMEN
BACKGROUND: Parkinson's disease (PD) is typically characterized by impairment of motor function. Gait disturbances similar to those observed in patients with PD can be observed in animals after injection of neurotoxin 6-hydroxydopamine (6-OHDA) to induce unilateral nigrostriatal dopamine depletion. Exercise has been shown to be a promising non-pharmacological approach to reduce the risk of neurodegenerative disease. METHODS: In this study, we investigated the long-term effects of voluntary running wheel exercise on gait phenotypes, depression, cognitive, rotational behaviors as well as histology in a 6-OHDA-lesioned rat model of PD. RESULTS: We observed that, when compared with the non-exercise controls, five-week voluntary exercise alleviated and postponed the 6-OHDA-induced gait deficits, including a significantly improved walking speed, step/stride length, base of support and print length. In addition, we found that the non-motor functions, such as novel object recognition and forced swim test, were also ameliorated by voluntary exercise. However, the rotational behavior of the exercise group did not show significant differences when compared with the non-exercise group. CONCLUSIONS: We first analyzed the detailed spatiotemporal changes of gait pattern to investigate the potential benefits after long-term exercise in the rat model of PD, which could be useful for future objective assessment of locomotor function in PD or other neurological animal models. Furthermore, these results suggest that short-term voluntary exercise is sufficient to alleviate cognition deficits and depressive behavior in 6-OHDA lesioned rats and long-term treatment reduces the progression of motor symptoms and elevates tyrosine hydroxylase (TH), Brain-derived neurotrophic factor (BDNF), bone marrow tyrosine kinase in chromosome X (BMX) protein expression level without affecting dopaminergic (DA) neuron loss in this PD rat model.
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Cognición , Actividad Motora , Enfermedad de Parkinson/fisiopatología , Enfermedad de Parkinson/psicología , Esfuerzo Físico , Animales , Conducta Animal , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Modelos Animales de Enfermedad , Dopamina/metabolismo , Neuronas Dopaminérgicas/metabolismo , Femenino , Marcha , Neuroprotección , Oxidopamina/efectos adversos , Enfermedad de Parkinson/etiología , Enfermedad de Parkinson/terapia , Proteínas Tirosina Quinasas/genética , Proteínas Tirosina Quinasas/metabolismo , Ratas , Sustancia Negra , Tirosina 3-Monooxigenasa/metabolismoRESUMEN
Stroke commonly leads to adult disability and death worldwide. Its major symptoms are spastic hemiplegia and discordant motion, consequent to neuronal cell death induced by brain vessel occlusion. Acetylcholinesterase (AChE) is upregulated and allied with inflammation and apoptosis after stroke. Recent studies suggest that AChE inhibition ameliorates ischemia-reperfusion injury and has neuroprotective properties. (-)-Phenserine, a reversible AChE inhibitor, has a broad range of actions independent of its AChE properties, including neuroprotective ones. However, its protective effects and detailed mechanism of action in the rat middle cerebral artery occlusion model (MCAO) remain to be elucidated. This study investigated the therapeutic effects of (-)-phenserine for stroke in the rat focal cerebral ischemia model and oxygen-glucose deprivation/reperfusion (OGD/RP) damage model in SH-SY5Y neuronal cultures. (-)-Phenserine mitigated OGD/PR-induced SH-SY5Y cell death, providing an inverted U-shaped dose-response relationship between concentration and survival. In MCAO challenged rats, (-)-phenserine reduced infarction volume, cell death and improved body asymmetry, a behavioral measure of stoke impact. In both cellular and animal studies, (-)-phenserine elevated brain-derived neurotrophic factor (BDNF) and B-cell lymphoma 2 (Bcl-2) levels, and decreased activated-caspase 3, amyloid precursor protein (APP) and glial fibrillary acidic protein (GFAP) expression, potentially mediated through the ERK-1/2 signaling pathway. These actions mitigated neuronal apoptosis in the stroke penumbra, and decreased matrix metallopeptidase-9 (MMP-9) expression. In synopsis, (-)-phenserine significantly reduced neuronal damage induced by ischemia/reperfusion injury in a rat model of MCAO and cellular model of OGD/RP, demonstrating that its anti-apoptotic/neuroprotective/neurotrophic cholinergic and non-cholinergic properties warrant further evaluation in conditions of brain injury.
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Apoptosis/efectos de los fármacos , Isquemia Encefálica/tratamiento farmacológico , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Fisostigmina/análogos & derivados , Daño por Reperfusión/tratamiento farmacológico , Animales , Apoptosis/fisiología , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patología , Hipoxia de la Célula/efectos de los fármacos , Hipoxia de la Célula/fisiología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Inhibidores de la Colinesterasa/farmacología , Relación Dosis-Respuesta a Droga , Glucosa/deficiencia , Humanos , Masculino , Neuronas/metabolismo , Neuronas/patología , Fisostigmina/farmacología , Ratas , Ratas Sprague-Dawley , Daño por Reperfusión/metabolismo , Daño por Reperfusión/patología , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/metabolismo , Accidente Cerebrovascular/patologíaRESUMEN
[This corrects the article DOI: 10.1371/journal.pone.0178186.].
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PURPOSE: Mild traumatic brain injury (mTBI) is a major public health concern. The apolipoprotein E (APOE) gene contains three polymorphisms, and the APOE4 polymorphism may affect several physiological states, such as the recovery from mTBI as well as sleep. This study aims to investigate the association between APOE4 with the recovery of sleep disturbance after mTBI. METHODS: From May 2012 to Aug 2015, 189 mTBI patients completed baseline (1st week post-mTBI) and follow-up (6th week post-mTBI) sleep assessments that involved using the Pittsburgh Sleep Quality Index (PSQI). APOE genotypes were determined by sequencing the products of polymerase chain reaction from genomic DNA. Statistical analyses were performed using the Wilcox signed-rank or chi-square test. RESULTS: Thirty-five (18.5%) participants were APOE4 carriers. At baseline, the demographic data and the severity of sleep disturbance were similar in both groups. APOE4 carriers demonstrated significant improvement in the overall PSQI score (8.34±3.9 at baseline and 7.43±3.99 at follow-up, p = 0.05) and scores of several PSQI subscales, including sleep disturbance, sleep latency, daytime dysfunction caused by sleepiness, and overall sleep quality, which was similar to APOE4 noncarriers. CONCLUSION: APOE4 is not associated with the recovery of sleep disturbance after mTBI.
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Apolipoproteína E4 , Conmoción Encefálica , Trastornos del Sueño-Vigilia , Alelos , Apolipoproteína E4/genética , Conmoción Encefálica/complicaciones , Conmoción Encefálica/genética , Humanos , Polimorfismo Genético , Trastornos del Sueño-Vigilia/genéticaRESUMEN
OBJECTIVE: Traumatic brain injury (TBI) is a major brain injury type commonly caused by traffic accidents, falls, violence, or sports injuries. To obtain mechanistic insights about TBI, experimental animal models such as weight-drop-induced TBI in rats have been developed to mimic closed-head injury in humans. However, the relationship between the mechanical impact level and neurological severity following weight-drop-induced TBI remains uncertain. In this study, we comprehensively investigated the relationship between physical impact and graded severity at various weight-drop heights. APPROACH: The acceleration, impact force, and displacement during the impact were accurately measured using an accelerometer, a pressure sensor, and a high-speed camera, respectively. In addition, the longitudinal changes in neurological deficits and balance function were investigated at 1, 4, and 7 days post TBI lesion. The inflammatory expression markers tested by Western blot analysis, including glial fibrillary acidic protein, beta-amyloid precursor protein, and bone marrow tyrosine kinase gene in chromosome X, in the frontal cortex, hippocampus, and corpus callosum were investigated at 1 and 7 days post-lesion. RESULTS: Gradations in impact pressure produced progressive degrees of injury severity in the neurological score and balance function. Western blot analysis demonstrated that all inflammatory expression markers were increased at 1 and 7 days post-impact injury when compared to the sham control rats. The severity of neurologic dysfunction and induction in inflammatory markers strongly correlated with the graded mechanical impact levels. CONCLUSIONS: We conclude that the weight-drop-induced TBI model can produce graded brain injury and induction of neurobehavioral deficits and may have translational relevance to developing therapeutic strategies for TBI.
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Lesiones Traumáticas del Encéfalo/fisiopatología , Animales , Conducta Animal , Fenómenos Biomecánicos , Lesiones Traumáticas del Encéfalo/metabolismo , Proteína Ácida Fibrilar de la Glía/metabolismo , Masculino , Ratas , Ratas Sprague-Dawley , Índice de Severidad de la EnfermedadRESUMEN
Mild traumatic brain injury (mTBI) is a major public health issue, representing 75-90% of all cases of TBI. In clinical settings, mTBI, which is defined as a Glascow Coma Scale (GCS) score of 13-15, can lead to various physical, cognitive, emotional, and psychological-related symptoms. To date, there are no pharmaceutical-based therapies to manage the development of the pathological deficits associated with mTBI. In this study, the neurotrophic and neuroprotective properties of glucose-dependent insulinotropic polypeptide (GIP), an incretin similar to glucagon-like peptide-1 (GLP-1), was investigated after its steady-state subcutaneous administration, focusing on behavior after mTBI in an in vivo animal model. The mTBI rat model was generated by a mild controlled cortical impact (mCCI) and used to evaluate the therapeutic potential of GIP. We used the Morris water maze and novel object recognition tests, which are tasks for spatial and recognition memory, respectively, to identify the putative therapeutic effects of GIP on cognitive function. Further, beam walking and the adhesive removal tests were used to evaluate locomotor activity and somatosensory functions in rats with and without GIP administration after mCCI lesion. Lastly, we used immunohistochemical (IHC) staining and Western blot analyses to evaluate the inflammatory markers, glial fibrillary acidic protein (GFAP), amyloid-ß precursor protein (APP), and bone marrow tyrosine kinase gene in chromosome X (BMX) in animals with mTBI. GIP was well tolerated and ameliorated mTBI-induced memory impairments, poor balance, and sensorimotor deficits after initiation in the post-injury period. In addition, GIP mitigated mTBI-induced neuroinflammatory changes on GFAP, APP, and BMX protein levels. These findings suggest GIP has significant benefits in managing mTBI-related symptoms and represents a novel strategy for mTBI treatment.
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Conmoción Encefálica/tratamiento farmacológico , Disfunción Cognitiva/tratamiento farmacológico , Polipéptido Inhibidor Gástrico/administración & dosificación , Mediadores de Inflamación/antagonistas & inhibidores , Desempeño Psicomotor/efectos de los fármacos , Animales , Conmoción Encefálica/metabolismo , Conmoción Encefálica/psicología , Disfunción Cognitiva/metabolismo , Disfunción Cognitiva/psicología , Humanos , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Inflamación/psicología , Mediadores de Inflamación/metabolismo , Inyecciones Subcutáneas , Masculino , Desempeño Psicomotor/fisiología , Ratas , Ratas Sprague-DawleyRESUMEN
BACKGROUND: A shift in glucose metabolism from oxidative phosphorylation to anaerobic glycolysis is the biochemical hallmark of malignant cancer cells. METHODS: In the present study, we demonstrated that Nodal stimulated the expression of glycolytic enzymes and decreased reliance on mitochondrial oxidative phosphorylation in human glioma cancer cells. The shift in glucose metabolism was mediated by induction of the hypoxia-inducible factor (HIF). RESULTS: Nodal protein expression was shown to be correlated with expression levels of glucose transporter (Glut)-1, hexokinase (HK)-II, pyruvate dehydrogenase kinase (PDK)-1, the phosphorylation level of pyruvate dehydrogenase (PDH), glucose uptake, and lactate accumulation in human glioma cells. These effects were inversely correlated with mitochondrial oxygen consumption and ATP production. Knockdown of Nodal expression with specific small hairpin RNA reduced Glut-1, HK-II, and PDK-1 expressions and PDH phosphorylation. Nodal knockdown also reduced glucose uptake and lactate generation, which in turn increased mitochondrial membrane potential (Ψ), O2 utilization, and ATP synthesis. The ectopic expression of Nodal in low-expressing Nodal glioma cells resulted in the opposite results compared with those of Nodal knockdown glioma cells. Treatment of cells with recombinant Nodal increased HIF-1 expression, and this effect was regulated at the transcriptional level. Blockage of the Nodal receptor by a pharmacological inhibitor or Nodal knockdown in U87MG cells decreased HIF-1α expression. Furthermore, HIF-1α knockdown in U87MG cells decreased Glut-1, HK-II, and PDK-1 expressions and PDH phosphorylation, which were similar to results in Nodal knockdown cells. CONCLUSION: Taken together, these results suggest that Nodal affects energy metabolism through HIF-1α.
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Metabolismo Energético , Glioma/metabolismo , Glioma/patología , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Mitocondrias/metabolismo , Proteína Nodal/metabolismo , Adenosina Trifosfato/metabolismo , Western Blotting , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Glucosa/metabolismo , Glucólisis , Humanos , Hipoxia/metabolismo , Hipoxia/patología , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Ácido Láctico/metabolismo , Luciferasas/metabolismo , Potencial de la Membrana Mitocondrial , Proteína Nodal/antagonistas & inhibidores , Proteína Nodal/genética , Consumo de Oxígeno , ARN Interferente Pequeño/genética , Células Tumorales CultivadasRESUMEN
Human malignant glioma cells are characterized by local invasion. In the present study, we investigated the role of osteopontin (OPN) in the invasiveness of human glioma cells isolated from grade IV tumors. We found that the expression levels of OPN in these cell lines paralleled matrix metalloproteinase-2 (MMP-2) expression and cell invasiveness potential. When U87MG glioma cells (with a high-OPN expression level) were stably transformed with specific small hairpin RNA to knock down OPN expression, MMP-2 secretion, cell invasiveness, and tumor growth in implanted brains were dramatically reduced. Conversely, forced expression of OPN in GBM-SKH glioma cells (which expressed OPN at a low level) increased MMP-2 secretion, enhanced cell invasiveness, and increased tumor growth in a rodent xenograft model. Expression of OPN was associated with increased expression of vimentin and decreased expression of glial fibrillary acidic protein. Treatment of glioma cells with 5-aza-2'-deoxycytidine (5-aza-dC) suppressed OPN expression in a concentration-dependent manner. Suppression of OPN expression by 5-aza-dC was associated with reductions in MMP-2 secretion, vimentin expression, cell invasion, intravasation, and tumor growth. These data suggest that OPN may play important roles in regulating cell invasion in glioma cells and that 5-aza-dC may serve as a therapeutic agent for human gliomas.
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Neoplasias Encefálicas/patología , Glioma/patología , Invasividad Neoplásica/patología , Osteopontina/metabolismo , Animales , Antineoplásicos/uso terapéutico , Azacitidina/análogos & derivados , Azacitidina/uso terapéutico , Western Blotting , Neoplasias Encefálicas/metabolismo , Línea Celular Tumoral , Decitabina , Electroforesis en Gel de Poliacrilamida , Glioma/metabolismo , Humanos , Inmunohistoquímica , Metaloproteinasa 2 de la Matriz/biosíntesis , Ratones , Ratones Desnudos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Vimentina/biosíntesis , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
We sought to investigate the molecular mechanisms by which rosiglitazone (RGZ) inhibits cell invasion in human glioma cells. In this study, we found that RGZ attenuated MMP-2 protein levels, MMP-2 gelatinolytic activity, and cell invasiveness through a PPAR-gamma independent pathway. RGZ increased mitogen activated protein kinase phosphatase-1 (MKP-1) expression. The addition of triptolide (a diterpenoid triepoxide, which blocked MKP-1 induction) abolished the inhibitory effects by RGZ. Furthermore, we demonstrated that the knock down of MKP-1 by MKP-1 specific small interference RNA reversed the reduction of MMP-2 secretion, and of cell invasiveness by RGZ. In contrast, the stable expression of MKP-1 in glioma cell lines decreased MMP-2 activity and cell invasiveness. These results suggest that RGZ may mediate the inhibitory effects through MKP-1 induction. Thus, MKP-1 could be a potential target in glioma therapy.