RESUMEN
Cathelicidin-related antimicrobial peptide (CRAMP) is an effector molecule of the innate immune system with direct antimicrobial and immunomodulatory activities; however, its role in neuroinflammatory responses and related diseases is not clearly understood. In particular, the expression of CRAMP and its functional role has not been previously studied in experimental autoimmune encephalomyelitis (EAE) or multiple sclerosis (MS). Here, we investigated the role of CRAMP in neuroinflammation, using an EAE mouse model of MS and postmortem patient tissues. We found that the CRAMP expression was increased in the spinal cords of EAE-induced mice. Immunofluorescence analysis revealed that CRAMP is mainly induced in reactive astrocytes in the inflamed spinal cord of EAE mice. A similar pattern of the LL-37 (human CRAMP) expression was observed in the brain and spinal cord tissues of patients with MS. An intrathecal injection of the CRAMP peptide in EAE mice accelerated the onset of symptoms and increased disease severity with augmented expression of inflammatory mediators, glial activation, infiltration of inflammatory cells, and demyelination. In addition, shRNA-mediated knockdown of Cramp in the spinal cord resulted in a milder disease course with less inflammation in EAE mice. We identified FPR2 on microglia as a CRAMP receptor and demonstrated that CRAMP potentiates IFN-γ-induced microglial activation via the STAT3 pathway. Taken together, our findings suggest that CRAMP is a novel mediator of astrocyte-microglia interactions in neuroinflammatory conditions such as EAE. Thus, CRAMP could be exploited as a biomarker or therapeutic target for the diagnosis or treatment of MS.
Asunto(s)
Encefalomielitis Autoinmune Experimental , Esclerosis Múltiple , Animales , Péptidos Catiónicos Antimicrobianos , Péptidos Antimicrobianos , Astrocitos/metabolismo , Comunicación , Encefalomielitis Autoinmune Experimental/tratamiento farmacológico , Encefalomielitis Autoinmune Experimental/metabolismo , Humanos , Inflamación/metabolismo , Ratones , Ratones Endogámicos C57BL , Microglía/metabolismo , Esclerosis Múltiple/metabolismo , Enfermedades Neuroinflamatorias , Médula Espinal/metabolismo , CatelicidinasRESUMEN
Neurotrophic factors (NTFs) are essential for cell growth, survival, synaptic plasticity, and maintenance of specific neuronal population in the central nervous system. Multiple studies have demonstrated that alterations in the levels and activities of NTFs are related to the pathology and symptoms of neurodegenerative disorders, such as Parkinson's disease (PD), Alzheimer's disease (AD), and Huntington's disease. Hence, the key molecule that can regulate the expression of NTFs is an important target for gene therapy coupling adeno-associated virus vector (AAV) gene. We have previously reported that the Ras homolog protein enriched in brain (Rheb)-mammalian target of rapamycin complex 1 (mTORC1) axis plays a vital role in preventing neuronal death in the brain of AD and PD patients. AAV transduction using a constitutively active form of Rheb exerts a neuroprotective effect through the upregulation of NTFs, thereby promoting the neurotrophic interaction between astrocytes and neurons in AD conditions. These findings suggest the role of Rheb as an important regulator of the regulatory system of NTFs to treat neurodegenerative diseases. In this review, we present an overview of the role of Rheb in neurodegenerative diseases and summarize the therapeutic potential of AAV serotype 1 (AAV1)-Rheb(S16H) transduction in the treatment of neurodegenerative disorders, focusing on diseases, such as AD and PD.
Asunto(s)
Enfermedades Neurodegenerativas/terapia , Parvovirinae/metabolismo , Proteína Homóloga de Ras Enriquecida en el Cerebro/metabolismo , Transducción Genética , Animales , Dependovirus , Humanos , Modelos Biológicos , Factores de Crecimiento Nervioso/metabolismoRESUMEN
Alzheimer's disease (AD) is the most frequent cause of age-related neurodegeneration and cognitive impairment, and there are currently no broadly effective therapies. The underlying pathogenesis is complex, but a growing body of evidence implicates mitochondrial dysfunction as a common pathomechanism involved in many of the hallmark features of the AD brain, such as formation of amyloid-beta (Aß) aggregates (amyloid plaques), neurofibrillary tangles, cholinergic system dysfunction, impaired synaptic transmission and plasticity, oxidative stress, and neuroinflammation, that lead to neurodegeneration and cognitive dysfunction. Indeed, mitochondrial dysfunction concomitant with progressive accumulation of mitochondrial Aß is an early event in AD pathogenesis. Healthy mitochondria are critical for providing sufficient energy to maintain endogenous neuroprotective and reparative mechanisms, while disturbances in mitochondrial function, motility, fission, and fusion lead to neuronal malfunction and degeneration associated with excess free radical production and reduced intracellular calcium buffering. In addition, mitochondrial dysfunction can contribute to amyloid-ß precursor protein (APP) expression and misprocessing to produce pathogenic fragments (e.g., Aß1-40). Given this background, we present an overview of the importance of mitochondria for maintenance of neuronal function and how mitochondrial dysfunction acts as a driver of cognitive impairment in AD. Additionally, we provide a brief summary of possible treatments targeting mitochondrial dysfunction as therapeutic approaches for AD.
Asunto(s)
Enfermedad de Alzheimer/genética , Disfunción Cognitiva/genética , Estrés Oxidativo/genética , Placa Amiloide/genética , Enfermedad de Alzheimer/patología , Encéfalo/metabolismo , Encéfalo/patología , Disfunción Cognitiva/patología , Humanos , Mitocondrias/genética , Mitocondrias/metabolismo , Mitocondrias/patología , Neuronas/metabolismo , Neuronas/patología , Placa Amiloide/metabolismo , Placa Amiloide/patologíaRESUMEN
To understand disease mechanisms, a large-scale analysis of human-yeast genetic interactions was performed. Of 1305 human disease genes assayed, 20 genes exhibited strong toxicity in yeast. Human-yeast genetic interactions were identified by en masse transformation of the human disease genes into a pool of 4653 homozygous diploid yeast deletion mutants with unique barcode sequences, followed by multiplexed barcode sequencing to identify yeast toxicity modifiers. Subsequent network analyses focusing on amyotrophic lateral sclerosis (ALS)-associated genes, such as optineurin (OPTN) and angiogenin (ANG), showed that the human orthologs of the yeast toxicity modifiers of these ALS genes are enriched for several biological processes, such as cell death, lipid metabolism, and molecular transport. When yeast genetic interaction partners held in common between human OPTN and ANG were validated in mammalian cells and zebrafish, MAP2K5 kinase emerged as a potential drug target for ALS therapy. The toxicity modifiers identified in this study may deepen our understanding of the pathogenic mechanisms of ALS and other devastating diseases.
Asunto(s)
Esclerosis Amiotrófica Lateral/genética , MAP Quinasa Quinasa 5/genética , Ribonucleasa Pancreática/genética , Factor de Transcripción TFIIIA/genética , Esclerosis Amiotrófica Lateral/patología , Esclerosis Amiotrófica Lateral/terapia , Animales , Proteínas de Ciclo Celular , Humanos , Proteínas de Transporte de Membrana , Terapia Molecular Dirigida , Proteínas Mutantes/genética , Mutación/genética , Mapas de Interacción de Proteínas/genética , Saccharomyces cerevisiae/genética , Eliminación de Secuencia/genética , Pez Cebra/genéticaRESUMEN
BACKGROUND: The FDA-approved small-molecule drug dasatinib is currently used as a treatment for chronic myeloid leukemia (CML). However, the effects of dasatinib on microglial and/or astrocytic neuroinflammatory responses and its mechanism of action have not been studied in detail. METHODS: BV2 microglial cells, primary astrocytes, or primary microglial cells were treated with dasatinib (100 or 250 nM) or vehicle (1% DMSO) for 30 min or 2 h followed by lipopolysaccharide (LPS; 200 ng/ml or 1 µg/ml) or PBS for 5.5 h. RT-PCR, real-time PCR; immunocytochemistry; subcellular fractionation; and immunohistochemistry were subsequently conducted to determine the effects of dasatinib on LPS-induced neuroinflammation. In addition, wild-type mice were injected with dasatinib (20 mg/kg, intraperitoneally (i.p.) daily for 4 days or 20 mg/kg, orally administered (p.o.) daily for 4 days or 2 weeks) or vehicle (4% DMSO + 30% polyethylene glycol (PEG) + 5% Tween 80), followed by injection with LPS (10 mg/kg, i.p.) or PBS. Then, immunohistochemistry was performed, and plasma IL-6, IL-1ß, and TNF-α levels were analyzed by ELISA. RESULTS: Dasatinib regulates LPS-induced proinflammatory cytokine and anti-inflammatory cytokine levels in BV2 microglial cells, primary microglial cells, and primary astrocytes. In BV2 microglial cells, dasatinib regulates LPS-induced proinflammatory cytokine levels by regulating TLR4/AKT and/or TLR4/ERK signaling. In addition, intraperitoneal injection and oral administration of dasatinib suppress LPS-induced microglial/astrocyte activation, proinflammatory cytokine levels (including brain and plasma levels), and neutrophil rolling in the brains of wild-type mice. CONCLUSIONS: Our results suggest that dasatinib modulates LPS-induced microglial and astrocytic activation, proinflammatory cytokine levels, and neutrophil rolling in the brain.
Asunto(s)
Astrocitos/metabolismo , Dasatinib/farmacología , Lipopolisacáridos/toxicidad , Microglía/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Factor de Transcripción STAT3/metabolismo , Animales , Animales Recién Nacidos , Astrocitos/efectos de los fármacos , Células Cultivadas , Dasatinib/uso terapéutico , Inflamación/inducido químicamente , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Microglía/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Ratas , Ratas Sprague-Dawley , Factor de Transcripción STAT3/antagonistas & inhibidoresRESUMEN
BACKGROUND: The FDA-approved small-molecule drug ibrutinib is an effective targeted therapy for patients with chronic lymphocytic leukemia (CLL). Ibrutinib inhibits Bruton's tyrosine kinase (BTK), a kinase involved in B cell receptor signaling. However, the potential regulation of neuroinflammatory responses in the brain by ibrutinib has not been comprehensively examined. METHODS: BV2 microglial cells were treated with ibrutinib (1 µM) or vehicle (1% DMSO), followed by lipopolysaccharide (LPS; 1 µg/ml) or PBS. RT-PCR, immunocytochemistry, and subcellular fractionation were performed to examine the effects of ibrutinib on neuroinflammatory responses. In addition, wild-type mice were sequentially injected with ibrutinib (10 mg/kg, i.p.) or vehicle (10% DMSO, i.p.), followed by LPS (10 mg/kg, i.p.) or PBS, and microglial and astrocyte activations were assessed using immunohistochemistry. RESULTS: Ibrutinib significantly reduced LPS-induced increases in proinflammatory cytokine levels in BV2 microglial and primary microglial cells but not in primary astrocytes. Ibrutinib regulated TLR4 signaling to alter LPS-induced proinflammatory cytokine levels. In addition, ibrutinib significantly decreased LPS-induced increases in p-AKT and p-STAT3 levels, suggesting that ibrutinib attenuates LPS-induced neuroinflammatory responses by inhibiting AKT/STAT3 signaling pathways. Interestingly, ibrutinib also reduced LPS-induced BV2 microglial cell migration by inhibiting AKT signaling. Moreover, ibrutinib-injected wild-type mice exhibited significantly reduced microglial/astrocyte activation and COX-2 and IL-1ß proinflammatory cytokine levels. CONCLUSIONS: Our data provide insights on the mechanisms of a potential therapeutic strategy for neuroinflammation-related diseases.
Asunto(s)
Antiinflamatorios/uso terapéutico , Citocinas/metabolismo , Inflamación/tratamiento farmacológico , Microglía/efectos de los fármacos , Pirazoles/uso terapéutico , Pirimidinas/uso terapéutico , Adenina/análogos & derivados , Animales , Animales Recién Nacidos , Línea Celular Transformada , Células Cultivadas , Medio de Cultivo Libre de Suero/farmacología , Ciclooxigenasa 2/genética , Ciclooxigenasa 2/metabolismo , Citocinas/genética , Modelos Animales de Enfermedad , Compuestos Heterocíclicos con 3 Anillos/farmacología , Inflamación/inducido químicamente , Lipopolisacáridos/efectos adversos , Masculino , Ratones , Ratones Endogámicos C57BL , Microglía/citología , Piperidinas , Inhibidores de Proteínas Quinasas/farmacología , Pirazoles/química , Pirimidinas/química , Ratas , Transducción de Señal/efectos de los fármacos , Cicatrización de Heridas/efectos de los fármacosRESUMEN
BACKGROUND: Neuroinflammation is associated with neurodegenerative diseases, including Alzheimer's disease (AD). Thus, modulating the neuroinflammatory response represents a potential therapeutic strategy for treating neurodegenerative diseases. Several recent studies have shown that dopamine (DA) and its receptors are expressed in immune cells and are involved in the neuroinflammatory response. Thus, we recently developed and synthesized a non-self-polymerizing analog of DA (CA140) and examined the effect of CA140 on neuroinflammation. METHODS: To determine the effects of CA140 on the neuroinflammatory response, BV2 microglial cells were pretreated with lipopolysaccharide (LPS, 1 µg/mL), followed by treatment with CA140 (10 µM) and analysis by reverse transcription-polymerase chain reaction (RT-PCR). To examine whether CA140 alters the neuroinflammatory response in vivo, wild-type mice were injected with both LPS (10 mg/kg, intraperitoneally (i.p.)) and CA140 (30 mg/kg, i.p.), and immunohistochemistry was performed. In addition, familial AD (5xFAD) mice were injected with CA140 or vehicle daily for 2 weeks and examined for microglial and astrocyte activation. RESULTS: Pre- or post-treatment with CA140 differentially regulated proinflammatory responses in LPS-stimulated microglia and astrocytes. Interestingly, CA140 regulated D1R levels to alter LPS-induced proinflammatory responses. CA140 significantly downregulated LPS-induced phosphorylation of ERK and STAT3 in BV2 microglia cells. In addition, CA140-injected wild-type mice exhibited significantly decreased LPS-induced microglial and astrocyte activation. Moreover, CA140-injected 5xFAD mice exhibited significantly reduced microglial and astrocyte activation. CONCLUSIONS: CA140 may be beneficial for preventing and treating neuroinflammatory-related diseases, including AD.
Asunto(s)
Enfermedad de Alzheimer/complicaciones , Antiinflamatorios/uso terapéutico , Dopamina/análogos & derivados , Encefalitis/tratamiento farmacológico , Encefalitis/etiología , Enfermedad de Alzheimer/sangre , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/patología , Precursor de Proteína beta-Amiloide/genética , Animales , Animales Recién Nacidos , Encéfalo/metabolismo , Encéfalo/patología , Células Cultivadas , Modelos Animales de Enfermedad , Dopamina/metabolismo , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Microglía/efectos de los fármacos , Mutación/genética , Proteínas del Tejido Nervioso/metabolismo , Polisacáridos/farmacología , Presenilina-1/genética , Ratas , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacosRESUMEN
The dorsal root ganglion (DRG) is a highly vulnerable site in diabetic neuropathy. Under diabetic conditions, the DRG is subjected to tissue ischemia or lower ambient oxygen tension that leads to aberrant metabolic functions. Metabolic dysfunctions have been documented to play a crucial role in the pathogenesis of diverse pain hypersensitivities. However, the contribution of diabetes-induced metabolic dysfunctions in the DRG to the pathogenesis of painful diabetic neuropathy remains ill-explored. In this study, we report that pyruvate dehydrogenase kinases (PDK2 and PDK4), key regulatory enzymes in glucose metabolism, mediate glycolytic metabolic shift in the DRG leading to painful diabetic neuropathy. Streptozotocin-induced diabetes substantially enhanced the expression and activity of the PDKs in the DRG, and the genetic ablation of Pdk2 and Pdk4 attenuated the hyperglycemia-induced pain hypersensitivity. Mechanistically, Pdk2/4 deficiency inhibited the diabetes-induced lactate surge, expression of pain-related ion channels, activation of satellite glial cells, and infiltration of macrophages in the DRG, in addition to reducing central sensitization and neuroinflammation hallmarks in the spinal cord, which probably accounts for the attenuated pain hypersensitivity. Pdk2/4-deficient mice were partly resistant to the diabetes-induced loss of peripheral nerve structure and function. Furthermore, in the experiments using DRG neuron cultures, lactic acid treatment enhanced the expression of the ion channels and compromised cell viability. Finally, the pharmacological inhibition of DRG PDKs or lactic acid production substantially attenuated diabetes-induced pain hypersensitivity. Taken together, PDK2/4 induction and the subsequent lactate surge induce the metabolic shift in the diabetic DRG, thereby contributing to the pathogenesis of painful diabetic neuropathy.
Asunto(s)
Diabetes Mellitus Experimental/complicaciones , Neuropatías Diabéticas/metabolismo , Neuropatías Diabéticas/patología , Ganglios Espinales/metabolismo , Ganglios Espinales/patología , Proteínas Serina-Treonina Quinasas/metabolismo , Animales , Células Cultivadas , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Neuropatías Diabéticas/genética , Glucólisis , Hiperglucemia/complicaciones , Hiperglucemia/genética , Hiperglucemia/metabolismo , Ácido Láctico/metabolismo , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas Serina-Treonina Quinasas/genética , Piruvato Deshidrogenasa Quinasa Acetil-Transferidora , Ratas Sprague-Dawley , Nervio Ciático/metabolismo , Nervio Ciático/patología , Regulación hacia ArribaRESUMEN
Because of the critical role of neuroinflammation in various neurological diseases, there are continuous efforts to identify new therapeutic targets as well as new therapeutic agents to treat neuroinflammatory diseases. Here we report the discovery of inflachromene (ICM), a microglial inhibitor with anti-inflammatory effects. Using the convergent strategy of phenotypic screening with early stage target identification, we show that the direct binding target of ICM is the high mobility group box (HMGB) proteins. Mode-of-action studies demonstrate that ICM blocks the sequential processes of cytoplasmic localization and extracellular release of HMGBs by perturbing its post-translational modification. In addition, ICM effectively downregulates proinflammatory functions of HMGB and reduces neuronal damage in vivo. Our study reveals that ICM suppresses microglia-mediated inflammation and exerts a neuroprotective effect, demonstrating the therapeutic potential of ICM in neuroinflammatory diseases.
Asunto(s)
Encéfalo/efectos de los fármacos , Proteína HMGB1/inmunología , Proteína HMGB2/inmunología , Compuestos Heterocíclicos de 4 o más Anillos/farmacología , Microglía/efectos de los fármacos , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Procesamiento Proteico-Postraduccional , Animales , Encéfalo/inmunología , Encéfalo/metabolismo , Encéfalo/patología , Línea Celular , Técnicas de Cocultivo , Expresión Génica , Proteína HMGB1/genética , Proteína HMGB1/metabolismo , Proteína HMGB2/genética , Proteína HMGB2/metabolismo , Inflamación/inducido químicamente , Inflamación/inmunología , Inflamación/patología , Inflamación/prevención & control , Lipopolisacáridos , Masculino , Ratones , Ratones Endogámicos C57BL , Microglía/inmunología , Microglía/patología , Neuroinmunomodulación , Neuronas/inmunología , Neuronas/patología , Unión Proteica , Factor de Necrosis Tumoral alfa/biosíntesis , Factor de Necrosis Tumoral alfa/inmunologíaRESUMEN
Lipocalin-2 (LCN2) plays an important role in cellular processes as diverse as cell growth, migration/invasion, differentiation, and death/survival. Furthermore, recent studies indicate that LCN2 expression and secretion by glial cells are induced by inflammatory stimuli in the central nervous system. The present study was undertaken to examine the regulation of LCN2 expression in experimental autoimmune encephalomyelitis (EAE) and to determine the role of LCN2 in the disease process. LCN2 expression was found to be strongly increased in spinal cord and secondary lymphoid tissues after EAE induction. In spinal cords astrocytes and microglia were the major cell types expressing LCN2 and its receptor 24p3R, respectively, whereas in spleens, LCN2 and 24p3R were highly expressed in neutrophils and dendritic cells, respectively. Furthermore, disease severity, inflammatory infiltration, demyelination, glial activation, the expression of inflammatory mediators, and the proliferation of MOG-specific T cells were significantly attenuated in Lcn2-deficient mice as compared with wild-type animals. Myelin oligodendrocyte glycoprotein-specific T cells in culture exhibited an increased expression of Il17a, Ifng, Rorc, and Tbet after treatment with recombinant LCN2 protein. Moreover, LCN2-treated glial cells expressed higher levels of proinflammatory cytokines, chemokines, and MMP-9. Adoptive transfer and recombinant LCN2 protein injection experiments suggested that LCN2 expression in spinal cord and peripheral immune organs contributes to EAE development. Taken together, these results imply LCN2 is a critical mediator of autoimmune inflammation and disease development in EAE and suggest that LCN2 be regarded a potential therapeutic target in multiple sclerosis.
Asunto(s)
Proteínas de Fase Aguda/metabolismo , Encefalomielitis Autoinmune Experimental/metabolismo , Lipocalinas/metabolismo , Tejido Linfoide/metabolismo , Proteínas Oncogénicas/metabolismo , Médula Espinal/metabolismo , Proteínas de Fase Aguda/genética , Animales , Astrocitos/metabolismo , Células Cultivadas , Células Dendríticas/metabolismo , Eliminación de Gen , Interferón gamma/genética , Interferón gamma/metabolismo , Interleucina-17/genética , Interleucina-17/metabolismo , Lipocalina 2 , Lipocalinas/genética , Tejido Linfoide/patología , Metaloproteinasa 9 de la Matriz/genética , Metaloproteinasa 9 de la Matriz/metabolismo , Ratones , Ratones Endogámicos C57BL , Vaina de Mielina/genética , Vaina de Mielina/metabolismo , Neutrófilos/metabolismo , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/genética , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/metabolismo , Proteínas Oncogénicas/genética , Receptores de Superficie Celular/genética , Receptores de Superficie Celular/metabolismo , Médula Espinal/patología , Linfocitos T/metabolismoRESUMEN
Although granule cell dispersion (GCD) in the hippocampus is known to be an important feature associated with epileptic seizures in temporal lobe epilepsy (TLE), the endogenous molecules that regulate GCD are largely unknown. In the present study, we have examined whether there is any change in AEG-1 expression in the hippocampus of a kainic acid (KA)-induced mouse model of TLE. In addition, we have investigated whether the modulation of astrocyte elevated gene-1 (AEG-1) expression in the dentate gyrus (DG) by intracranial injection of adeno-associated virus 1 (AAV1) influences pathological phenotypes such as GCD formation and seizure susceptibility in a KA-treated mouse. We have identified that the protein expression of AEG-1 is upregulated in the DG of a KA-induced mouse model of TLE. We further demonstrated that AEG-1 upregulation by AAV1 delivery in the DG-induced anticonvulsant activities such as the delay of seizure onset and inhibition of spontaneous recurrent seizures (SRS) through GCD suppression in the mouse model of TLE, while the inhibition of AEG-1 expression increased susceptibility to seizures. The present observations suggest that AEG-1 is a potent regulator of GCD formation and seizure development associated with TLE, and the significant induction of AEG-1 in the DG may have therapeutic potential against epilepsy.
Asunto(s)
Epilepsia del Lóbulo Temporal , Epilepsia , Animales , Ratones , Astrocitos/metabolismo , Giro Dentado/metabolismo , Epilepsia/metabolismo , Epilepsia del Lóbulo Temporal/inducido químicamente , Epilepsia del Lóbulo Temporal/genética , Epilepsia del Lóbulo Temporal/tratamiento farmacológico , Hipocampo/metabolismo , Ácido Kaínico/efectos adversos , Ácido Kaínico/metabolismo , Convulsiones/inducido químicamente , Convulsiones/genética , Convulsiones/metabolismoRESUMEN
Jaceosidin is a naturally occurring flavone with pharmacological activity. Jaceosidin, as one of the major constituents of the medicinal herbs of the genus Artemisia, has been shown to exert anticancer, anti-oxidative, anti-inflammatory, and immunosuppressive effects. This study was undertaken to determine the effect of jaceosidin on microglia and neuroinflammation. Microglia are the innate immune cells in the central nervous system, and they play a central role in the initiation and maintenance of neuroinflammation. We report that jaceosidin inhibits inflammatory activation of microglia, reducing nitric oxide (NO) production and proinflammatory cytokine expression. IC50 for NO inhibition was 27 ± 0.4 µM. The flavone also attenuated microglial neurotoxicity in the microglia/neuroblastoma co-culture. Systemic injection of jaceosidin ameliorated neuroinflammation in the mouse model of experimental allergic encephalomyelitis. These results indicate that plant flavone jaceosidin is a microglial inhibitor with anti-neuroinflammation activity.
Asunto(s)
Antiinflamatorios/farmacología , Flavonoides/farmacología , Inflamación/metabolismo , Microglía/efectos de los fármacos , Animales , Artemisia/química , Línea Celular , Técnicas de Cocultivo , Citocinas/metabolismo , Encefalomielitis Autoinmune Experimental/tratamiento farmacológico , Femenino , Inflamación/patología , Ratones , Ratones Endogámicos C57BL , Microglía/metabolismo , Óxido Nítrico/metabolismo , RatasRESUMEN
This study investigated the therapeutic effects of transplanting human mesenchymal stem cells (hMSCs) into wild-type mice that were intraperitoneally administered cytosine arabinoside (Ara-C) to develop cerebellar ataxia (CA) during the first three postnatal days. hMSCs were intrathecally injected into 10-week-old mice once or thrice at 4-week intervals. Compared to the nontreated mice, the hMSC-treated mice showed improved motor and balance coordination, as measured using the rotarod, open-field, and ataxic scoring assessments, and increased protein levels in Purkinje and cerebellar granule cells, as measured using calbindin and NeuN protein markers. Multiple hMSC injections preserved Ara-C-induced cerebellar neuronal loss and improved cerebellar weight. Furthermore, the hMSC implantation significantly elevated the levels of neurotrophic factors, including brain-derived and glial cell line-derived neurotrophic factors, and suppressed TNF-α-, IL-1ß-, and iNOS-mediated proinflammatory responses. Collectively, our results demonstrate that hMSCs exhibit therapeutic potential for Ara-C-induced CA by protecting neurons through the stimulation of neurotrophic factors and inhibition of cerebellar inflammatory responses, which can improve motor behavior and alleviate ataxia-related neuropathology. In summary, this study suggests that hMSC administration, particularly multiple treatments, can effectively treat ataxia-related symptoms with cerebellar toxicity.
RESUMEN
Alzheimer's disease (AD) is a neurodegenerative disorder characterized by a progressive loss of memory and cognition. One of the hallmarks of AD is the accumulation of beta-amyloid (Aß). Although endoplasmic reticulum stress, mitochondrial dysfunction, and oxidative stress have been implicated in Aß toxicity, the molecular mechanism(s) of Aß-induced neurotoxicity are not fully understood. In this study, we present evidence that the glia-derived stress protein metallothionein (MT) attenuates Aß-induced neurotoxicity by unique mechanisms. MT expression was increased in brain astrocytes of a NSE-APPsw transgenic mouse model of AD. Astrocyte-derived MT protected N2a neuroblastoma cells and primary cortical neurons against Aß toxicity with concurrent reduction of reactive oxygen species levels. MT reversed Aß-induced down-regulation of Bcl-2 and survival signaling in neuroblastoma cells. Moreover, MT inhibited Aß-induced proinflammatory cytokine production from microglia. The neurotoxicity of Aß-stimulated microglia was significantly attenuated by MT-I. The results indicate that MT released from reactive astrocytes may antagonize Aß neurotoxicity by direct inhibition of Aß neurotoxicity and indirect suppression of neurotoxic microglial activation. These findings broaden the understanding of neurotoxic mechanisms of Aß and the crosstalk between Aß and MT in AD.
Asunto(s)
Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Astrocitos/metabolismo , Metalotioneína/metabolismo , Microglía/metabolismo , Animales , Fragmentación del ADN , Modelos Animales de Enfermedad , Ensayo de Inmunoadsorción Enzimática , Immunoblotting , Inmunohistoquímica , Ratones , Ratones Transgénicos , Estrés Oxidativo/fisiología , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
Recent studies have suggested that mouse cathelicidin-related antimicrobial peptide (CRAMP) and its human homologue leucine leucine-37 (LL-37) play critical roles in innate immune responses. Here, we studied the role of mouse CRAMP in bacterial endotoxin lipopolysaccharide (LPS)-induced neuroinflammation. CRAMP peptide treatment significantly inhibited LPS-mediated inflammatory activation of glial cells in culture. In the animal model of LPS-induced neuroinflammation, CRAMP expression was highly induced in multiple cell types, such as astrocytes, microglia, and neurons. Injection of exogenous CRAMP peptide significantly inhibited inflammatory cytokine expression and the reactivity of glial cells in the mouse brain following intraperitoneal or intracerebroventricular LPS administration. Altogether, results of the study suggest that CRAMP plays an important part in containment of LPS-induced neuroinflammatory responses, and that CRAMP can be exploited for the development of targeted therapies for neuroinflammatory conditions associated with bacterial infection.
Asunto(s)
Péptidos Catiónicos Antimicrobianos , Microglía , Animales , Ratones , Humanos , Péptidos Catiónicos Antimicrobianos/farmacología , Péptidos Catiónicos Antimicrobianos/metabolismo , Leucina , Ratones Endogámicos C57BL , Microglía/metabolismo , Lipopolisacáridos/farmacología , Lipopolisacáridos/metabolismoRESUMEN
BACKGROUND AND PURPOSE: There is a scarcity of information regarding the role of prothrombin kringle-2 (pKr-2), which can be generated by active thrombin, in hippocampal neurodegeneration and Alzheimer's disease (AD). EXPERIMENTAL APPROACH: To assess the role of pKr-2 in association with the neurotoxic symptoms of AD, we determined pKr-2 protein levels in post-mortem hippocampal tissues of patients with AD and the hippocampi of five familial AD (5XFAD) mice compared with those of age-matched controls and wild-type (WT) mice, respectively. In addition, we investigated whether the hippocampal neurodegeneration and object memory impairments shown in 5XFAD mice were mediated by changes to pKr-2 up-regulation. KEY RESULTS: Our results demonstrated that pKr-2 was up-regulated in the hippocampi of patients with AD and 5XFAD mice, but was not associated with amyloid-ß aggregation in 5XFAD mice. The up-regulation of pKr-2 expression was inhibited by preservation of the blood-brain barrier (BBB) via addition of caffeine to their water supply or by treatment with rivaroxaban, an inhibitor of factor Xa that is associated with thrombin production. Moreover, the prevention of up-regulation of pKr-2 expression reduced neurotoxic symptoms, such as hippocampal neurodegeneration and object recognition decline due to neurotoxic inflammatory responses in 5XFAD mice. CONCLUSION AND IMPLICATIONS: We identified a novel pathological mechanism of AD mediated by abnormal accumulation of pKr-2, which functions as an important pathogenic factor in the adult brain via blood brain barrier (BBB) breakdown. Thus, pKr-2 represents a novel target for AD therapeutic strategies and those for related conditions.
Asunto(s)
Enfermedad de Alzheimer , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Animales , Modelos Animales de Enfermedad , Hipocampo/metabolismo , Humanos , Kringles , Ratones , Ratones Transgénicos , Protrombina/metabolismo , Protrombina/uso terapéutico , TrombinaRESUMEN
The timely diagnosis and therapeutic monitoring of human renal cell carcinoma (RCC) is limited by the lack of specific biomarkers. To identify candidate RCC biomarkers, we used 2-DE gel electrophoresis with mass spectrometry and 2-DE spot intensity-based ROC analysis to analyze 18 sets of paired normal and RCC tumor tissue including conventional, papillary, and chromophobe subtypes. Validation was performed with RCC patient plasma samples and confirmed by clustergram, shRNA, and immunohistochemistry assays. Cardinal candidates were evaluated by ELISA. The leading candidate biomarker that was upregulated in RCC samples according to the clustergram and validation analysis was nicotinamide N-methyltransferase (NNMT) (13/15, P < 0.0001). Other upregulated candidate biomarkers that were identified by this method include ferritin, hNSE, NM23, secretagogin, and L-plastin. The upregulation of NNMT in RCC was confirmed by immunoblotting and immunohistochemistry. Analysis of fractionated membrane-associated proteins identified CAP-G, mitofillin, tubulin alpha, RBBP7, and HSP27. Of these, RBBP7 and HSP27 were highly expressed in the chromophobe subtype of RCC (3/3) but were absent from conventional RCC (0/3). The triple combination of the NNMT, FTL, and hNSE biomarkers had the highest predictive capacity of 0.993, while NNMT was the single, most powerful candidate diagnostic biomarker for all types of RCC.
Asunto(s)
Biomarcadores de Tumor/metabolismo , Carcinoma de Células Renales/metabolismo , Neoplasias Renales/metabolismo , Nicotinamida N-Metiltransferasa/metabolismo , Proteoma/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/análisis , Carcinoma de Células Renales/diagnóstico , Línea Celular Tumoral , Análisis por Conglomerados , Regulación hacia Abajo , Electroforesis en Gel Bidimensional , Femenino , Humanos , Immunoblotting , Inmunohistoquímica , Neoplasias Renales/diagnóstico , Masculino , Proteínas de la Membrana/análisis , Proteínas de la Membrana/metabolismo , Persona de Mediana Edad , Nicotinamida N-Metiltransferasa/análisis , Proteoma/análisis , Curva ROC , Reproducibilidad de los Resultados , Regulación hacia ArribaRESUMEN
Cerebellar ataxias (CAs) are neurological diseases characterized by loss of muscle coordination that is a result of damage and inflammation to the cerebellum. Despite considerable efforts in basic and clinical research, most CAs are currently incurable. In this study, we evaluated the therapeutic potential of human mesenchymal stem cells (hMSCs) against CAs associated with neuroinflammation. We observed that hMSC treatment significantly inhibited the symptoms of ataxia in lipopolysaccharide (LPS)-induced inflammatory CA (ICA) mice, which were recently reported as a potential animal model of ICA, through the anti-inflammatory effect of hMSC-derived TNFα-stimulated gene-6 (TSG-6), the protection of Purkinje cells by inhibition of apoptosis, and the modulatory effect for microglial M2 polarization. Thus, our results suggest that hMSC treatment may be an effective therapeutic approach for preventing or improving ataxia symptoms.
RESUMEN
Most cerebellar ataxias (CAs) are incurable neurological disorders, resulting in a lack of voluntary control by inflamed or damaged cerebellum. Although CA can be either directly or indirectly related to cerebellar inflammation, there is no suitable animal model of CA with neuroinflammation. In this study, we evaluated the utility of an intracerebellar injection of lipopolysaccharide (LPS) to generate an animal model of inflammatory CA. We observed that LPS administration induced the expression of pro-inflammatory molecules following activation of glial cells. In addition, the administration of LPS resulted in apoptotic Purkinje cell death and induced abnormal locomotor activities, such as impaired motor coordination and abnormal hindlimb clasping posture. Our results suggest that intracerebellar LPS administration in experimental animals may be useful for studying the inflammatory component of CA.
Asunto(s)
Ataxia Cerebelosa/inducido químicamente , Inflamación/inducido químicamente , Lipopolisacáridos/administración & dosificación , Animales , Células Cultivadas , Cerebelo/efectos de los fármacos , Modelos Animales de Enfermedad , Masculino , Ratones , Ratones Endogámicos C57BL , Neuroglía/efectos de los fármacos , Células de Purkinje/efectos de los fármacosRESUMEN
Recently, we reported that ALWPs, which we developed by combining Liuwei Dihuang pills (LWPs) with antler, regulate the LPS-induced neuroinflammatory response and rescue LPS-induced short- and long-term memory impairment in wild-type (WT) mice. In the present study, we examined the effects of ALWPs on Alzheimer's disease (AD) pathology and cognitive function in WT mice as well as 5x FAD mice (a mouse model of AD). We found that administration of ALWPs significantly reduced amyloid plaque levels in 5x FAD mice and significantly decreased amyloid ß (Aß) levels in amyloid precursor protein (APP)-overexpressing H4 cells. In addition, ALWPs administration significantly suppressed tau hyperphosphorylation in 5x FAD mice. Oral administration of ALWPs significantly improved long-term memory in scopolamine (SCO)-injected WT mice and 5x FAD mice by altering dendritic spine density. Importantly, ALWPs promoted spinogenesis in primary hippocampal neurons and WT mice and modulated the dendritic spine number in an extracellular signal-regulated kinase (ERK)-dependent manner. Taken together, our results suggest that ALWPs are a candidate therapeutic drug for AD that can modulate amyloid plaque load, tau phosphorylation, and synaptic/cognitive function.