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The transcriptional coactivator PGC-1α has been implicated in the regulation of multiple metabolic processes. However, the previously reported metabolic phenotypes of mice deficient in PGC-1α have been inconsistent. PGC-1α exists as multiple isoforms, including variants transcribed from an alternative first exon. We show here that alternative PGC-1α variants are the main entity that increases PGC-1α during exercise. These variants, unlike the canonical isoform of PGC-1α, are robustly upregulated in human skeletal muscle after exercise. Furthermore, the extent of this upregulation correlates with oxygen consumption. Mice lacking these variants manifest impaired energy expenditure during exercise, leading to the development of obesity and hyperinsulinemia. The alternative variants are also upregulated in brown adipose tissue in response to cold exposure, and mice lacking these variants are intolerant of a cold environment. Our findings thus indicate that an increase in PGC-1α expression, attributable mostly to upregulation of alternative variants, is pivotal for adaptive enhancement of energy expenditure and heat production and thereby essential for the regulation of whole-body energy metabolism.
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Tejido Adiposo Pardo , Empalme Alternativo , Metabolismo Energético , Músculo Esquelético , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma , Metabolismo Energético/genética , Animales , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/genética , Humanos , Ratones , Empalme Alternativo/genética , Masculino , Músculo Esquelético/metabolismo , Tejido Adiposo Pardo/metabolismo , Ratones Endogámicos C57BL , Condicionamiento Físico Animal , Obesidad/metabolismo , Obesidad/genética , Termogénesis/genética , Consumo de Oxígeno , Ejercicio Físico , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Adulto , Ratones NoqueadosRESUMEN
Background: Thromboembolism is a significant complication for patients with cancer, leading to treatment interruptions and poor outcomes. Objectives: The aim of this study was to investigate the incidence of arterial thromboembolism (ATE) within cancer populations, identify the predictors of ATE, and determine its survival impact. Methods: A retrospective multicenter study was performed using data from the Osaka Cancer Registry linked with administrative data from 2010 to 2015. Patients were monitored for 5 years after cancer diagnosis, and ATE incidence was calculated with death as a competing risk. Fine and Gray competing risk regression models and Cox proportional hazards models were used to evaluate the predictors of ATE and the survival impact. Restricted mean survival time (RMST) was used to assess whether antithrombotic therapy after ATE contributed to improved survival. Results: The cohort comprised 97,448 patients with cancer (42.3% women, median age 70 years). ATE incidence displayed an annual increase, peaking 1 year after cancer diagnosis (1-, 2-, 3-, 4-, and 5-year cumulative incidences were 1.29%, 1.77%, 2.05%, 2.22%, and 2.32%, respectively). Male sex, advanced age, advanced cancer stage, and hematologic malignancies correlated with a high risk for ATE. Patients with ATE had a 2-fold increased risk for mortality compared with those without ATE. The 90-day and 1-year RMST differences for those on antithrombotic therapy were 13.3 days (95% CI: 10.4-16.2 days; P < 0.001) and 57.8 days (95% CI: 43.1-72.5 days; P < 0.001), favoring the antithrombotic therapy group. The RMST differences varied by cancer stage. Conclusions: The risk for ATE varies according to sex, age, and cancer progression and type. Antithrombotic therapy after ATE is associated with improved survival among patients with cancer.
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Most studies on fat appetite have focused on long-chain triglycerides (LCTs) due to their obesogenic properties. Medium-chain triglycerides (MCTs), conversely, exhibit antiobesogenic effects; however, the regulation of MCT intake remains elusive. Here, we demonstrate that mice can distinguish between MCTs and LCTs, and the specific appetite for MCTs is governed by hepatic ß-oxidation. We generated liver-specific medium-chain acyl-CoA dehydrogenase (MCAD)-deficient (MCADL-/-) mice and analyzed their preference for MCT and LCT solutions using glyceryl trioctanoate (C8-TG), glyceryl tridecanoate (C10-TG), corn oil, and lard oil in two-bottle choice tests conducted over 8 days. In addition, we used lick microstructure analyses to evaluate the palatability and appetite for MCT and LCT solutions. Finally, we measured the expression levels of genes associated with fat ingestion (Galanin, Qrfp, and Nmu) in the hypothalamus 2 h after oral gavage of fat. Compared with control mice, MCADL-/- mice exhibited a significantly reduced preference for MCT solutions, with no alteration in the preference for LCTs. Lick analysis revealed that MCADL-/- mice displayed a significantly decreased appetite for MCT solutions only while the palatability of both MCT and LCT solutions remained unaffected. Hypothalamic Galanin expression in control mice was elevated by oral gavage of C8-TG but not by LCTs, and this response was abrogated in MCADL-/- mice. In summary, our data suggest that hepatic ß-oxidation is required for MCT-specific appetite but not for LCT-specific appetite. The induction of hypothalamic galanin upon MCT ingestion, dependent on hepatic ß-oxidation, could be involved in the regulation of MCT-specific appetite.NEW & NOTEWORTHY Whether and how medium-chain triglyceride (MCT) intake is regulated remains unknown. Here, we showed that mice can discriminate between MCTs and LCTs. Hepatic ß-oxidation participates in MCT-specific appetite, and hypothalamic galanin may be one of the factors that regulate MCT intake. Because of the antiobesity effects of MCTs, studying MCT-specific appetite may help combat obesity by promoting the intake of MCTs instead of LCTs.
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Acil-CoA Deshidrogenasa , Apetito , Ácidos Grasos , Hígado , Ratones Noqueados , Oxidación-Reducción , Triglicéridos , Animales , Triglicéridos/metabolismo , Ratones , Oxidación-Reducción/efectos de los fármacos , Hígado/metabolismo , Hígado/efectos de los fármacos , Masculino , Ácidos Grasos/metabolismo , Apetito/efectos de los fármacos , Apetito/fisiología , Acil-CoA Deshidrogenasa/metabolismo , Acil-CoA Deshidrogenasa/genética , Ratones Endogámicos C57BL , Hipotálamo/metabolismo , Hipotálamo/efectos de los fármacosRESUMEN
BACKGROUND: Covert atrial fibrillation (AF) is a major cause of cryptogenic stroke. This study investigated whether a dose-dependent relationship exists between the frequency of premature atrial contractions (PACs) and AF detection in patients with cryptogenic stroke using an insertable cardiac monitor (ICM). METHODS: We enrolled consecutive patients with cryptogenic stroke who underwent ICM implantation between October 2016 and September 2020 at 8 stroke centers in Japan. Patients were divided into 3 groups according to the PAC count on 24-hour Holter ECG: ≤200 (group L), >200 to ≤500 (group M), and >500 (group H). We defined a high AF burden as above the median of the cumulative duration of AF episodes during the entire monitoring period. We evaluated the association of the frequency of PACs with AF detection using log-rank trend test and Cox proportional hazard model and with high AF burden using logistic regression model, adjusting for age, sex, CHADS2 score. RESULTS: Of 417 patients, we analyzed 381 patients with Holter ECG and ICM data. The median age was 70 (interquartile range, 59.5-76.5), 246 patients (65%) were males, and the median duration of ICM recording was 605 days (interquartile range, 397-827 days). The rate of new AF detected by ICM was higher in groups with more frequent PAC (15.5%/y in group L [n=277] versus 44.0%/y in group M [n=42] versus 71.4%/y in group H [n=62]; log-rank trend P<0.01). Compared with group L, the adjusted hazard ratios for AF detection in groups M and H were 2.11 (95% CI, 1.24-3.58) and 3.23 (95% CI, 2.07-5.04), respectively, and the adjusted odds ratio for high AF burden in groups M and H were 2.57 (95% CI, 1.14-5.74) and 4.25 (2.14-8.47), respectively. CONCLUSIONS: The frequency of PACs was dose-dependently associated with AF detection in patients with cryptogenic stroke.
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Fibrilación Atrial , Complejos Atriales Prematuros , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Masculino , Humanos , Anciano , Femenino , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/epidemiología , Fibrilación Atrial/complicaciones , Complejos Atriales Prematuros/diagnóstico , Complejos Atriales Prematuros/epidemiología , Complejos Atriales Prematuros/complicaciones , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular Isquémico/complicaciones , Electrocardiografía AmbulatoriaRESUMEN
Although low-dose direct oral anticoagulants (DOACs) are recommended for patients at high risk of bleeding complications, it remains unclear whether the dose reduction in real-world setting is also appropriate in patients after large-vessel occlusion (LVO) stroke. This study hypothesized that patients with atrial fibrillation (AF) and LVO receiving low-dose DOACs have an increased risk of ischemic and hemorrhagic events. The study aimed to assess 1 year morbidity and mortality in patients treated with standard-dose and low-dose apixaban after LVO stroke. A post hoc analysis was performed using the acute LVO registry data, which enrolled patients with AF and LVO who received apixaban within 14 days of stroke onset. The incidences of ischemic events (ischemic stroke, acute coronary syndrome, acute myocardial infarction, and systemic embolism), major bleeding events, and death from any cause were compared between patients receiving standard- and low-dose apixaban. Of 643 patients diagnosed with LVO, 307 (47.7%) received low-dose apixaban. After adjustment for clinically relevant variables, no significant differences were observed in the incidence of ischemic events (adjusted hazard ratio [aHR]: 2.12, 95% confidence interval [CI] 0.75-6.02), major bleeding events (aHR: 1.17, 95% CI 0.50-2.73), and death from any cause (aHR: 1.95, 95% CI 0.78-4.89) between patients receiving standard- and low-dose apixaban. No significant differences were observed in the incidence of ischemic events, major bleeding events, or death from any cause between patients with AF and LVO receiving standard- and low-dose apixaban.
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Fibrilación Atrial , Accidente Cerebrovascular Isquémico , Pirazoles , Accidente Cerebrovascular , Humanos , Anticoagulantes/uso terapéutico , Accidente Cerebrovascular/etiología , Hemorragia/inducido químicamente , Piridonas/uso terapéutico , Fibrilación Atrial/tratamiento farmacológico , Accidente Cerebrovascular Isquémico/complicaciones , MorbilidadRESUMEN
BACKGROUND: Atrial fibrillation (AF) is known to be a strong risk factor for stroke. However, the risk of stroke recurrence in patients with cryptogenic stroke with AF detected after stroke by an insertable cardiac monitor (ICM) is not well known. We sought to evaluate the risk of ischemic stroke recurrence in patients with cryptogenic stroke with and without ICM-detected AF. METHODS AND RESULTS: We retrospectively reviewed patients with cryptogenic stroke who underwent ICM implantation at 8 stroke centers in Japan. Cox regression models were developed using landmark analysis and time-dependent analysis. We set the target sample size at 300 patients based on our estimate of the annualized incidence of ischemic stroke recurrence to be 3% in patients without AF detection and 9% in patients with AF detection. Of the 370 patients, 121 were found to have AF, and 110 received anticoagulation therapy after AF detection. The incidence of ischemic stroke recurrence was 4.0% in 249 patients without AF detection and 5.8% in 121 patients with AF detection (P=0.45). In a landmark analysis, the risk of ischemic stroke recurrence was not higher in patients with AF detected ≤90 days than in those without (hazard ratio, 1.47 [95% CI, 0.41-5.28]). In a time-dependent analysis, the risk of ischemic stroke recurrence did not increase after AF detection (hazard ratio, 1.77 [95% CI, 0.70-4.47]). CONCLUSIONS: The risk of ischemic stroke recurrence in patients with cryptogenic stroke with ICM-detected AF, 90% of whom were subsequently anticoagulated, was not higher than in those without ICM-detected AF.
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Fibrilación Atrial , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Fibrilación Atrial/complicaciones , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/epidemiología , Accidente Cerebrovascular Isquémico/complicaciones , Estudios Retrospectivos , Electrocardiografía Ambulatoria/métodos , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/etiologíaRESUMEN
BACKGROUND: Patients with acute ischemic stroke and active cancer have more severe neurological symptoms, elevated risks of stroke recurrence, and death compared with the general population. We examined whether von Willebrand factor (vWF) antigen levels at stroke onset were associated with the poor outcomes of patients with stroke and cancer. METHODS AND RESULTS: Using data from 90 patients with acute ischemic stroke and active cancer who were registered in the SCAN (Ischemic Stroke in Patients With Cancer and Neoplasia) study, a prospective multicenter, observational study in Japan, we divided patients into 2 groups according to their median vWF antigen levels (high, n=46; or low, n=44). The high-vWF group had a significantly higher initial National Institutes of Health Stroke Scale score (median, 7 [interquartile range, 3-11.25] versus 3 [interquartile range, 1-8.5]; P<0.05) and a significantly higher incidence of cryptogenic stroke (32 [70%] versus 16 [36%]; P<0.01) and venous thromboembolism (7 [15%] versus 0 [0%]; P<0.01), as well as multiple lesions (28 [62%] versus 12 [27%]; P<0.001), than the low-vWF group. We observed no significant difference in the rate of stroke recurrence within 1 year between the groups. However, increased vWF levels were an independent predictor of death within 1 year of stroke onset, after adjusting for potential confounders (odds ratio, 6.77 [95% CI, 1.49-30.78]; P<0.05). CONCLUSIONS: Elevated vWF antigen levels were associated with adverse outcomes in patients with cancer-associated stroke and may represent a useful biomarker to guide future therapeutic interventions.
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Accidente Cerebrovascular Isquémico , Neoplasias , Accidente Cerebrovascular , Humanos , Accidente Cerebrovascular Isquémico/complicaciones , Neoplasias/complicaciones , Neoplasias/epidemiología , Estudios Prospectivos , Factores de Riesgo , Accidente Cerebrovascular/diagnóstico , Factor de von Willebrand , Estudios Multicéntricos como Asunto , Estudios Observacionales como AsuntoRESUMEN
BACKGROUND: The effect of nutritional status on survival in ischemic stroke patients with active cancer remains unclear. METHODS: This study retrospectively evaluated ischemic stroke patients with active cancer admitted to a university hospital in Japan between 2006 and 2016. Patients were followed for 2 years after stroke. The controlling nutritional status (CONUT) score was used to classify undernutrition degree into 4 groups: normal, light, moderate, and severe. Survival rates were compared using the Kaplan-Meier method. Hazard ratio (HR) and 95 % confidence intervals (CIs) for mortality were calculated using Cox regression models. RESULTS: A total of 158 patients (31 % women; median age: 71 years) were analyzed. Of these, 47 % had distant metastasis. The median (interquartile range) National Institute of Health Stroke Scale and CONUT scores were 4 (1-10) and 5 (3-7), respectively. Kaplan-Meier curve indicated that patients with poorer nutritional status had worse outcomes (overall log-rank test, p < 0.001). The univariable Cox regression analysis showed that the HR (95 % CI) for the light, moderate, and severe groups were 1.14 (0.45-2.86), 3.01 (1.27-7.12), and 2.94 (1.10-7.84), respectively. This statistical significance did not persist after adjustment for potential confounders (HR [95 % CI] for the light, moderate, and severe groups were 0.95 [0.36-2.49], 1.56 [0.57-4.28], and 1.34 [0.37-4.92], respectively). Past stroke, distant metastasis, and plasma D-dimer levels on admission were independent predictors of prognosis. CONCLUSIONS: This single-center, retrospective study suggests that nutritional status serves as a prognostic indicator for ischemic stroke patients with active cancer. However, the effect is not statistically independent.
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Accidente Cerebrovascular Isquémico , Desnutrición , Neoplasias , Accidente Cerebrovascular , Humanos , Femenino , Anciano , Masculino , Estado Nutricional , Estudios Retrospectivos , PronósticoRESUMEN
Cluster of differentiation 36 (CD36) is a scavenger receptor expressed in various vertebrate cells that contains diverse ligands, including long-chain fatty acids. This receptor has recently been suggested as a captor of specific volatile odorants (e.g., aliphatic acetates) in the mammalian nasal epithelium. This study used a fluorescence-intensifying assay to produce the first evidence that lauric acid, an odorous fatty acid, directly binds to CD36. This expansion of the repertoire of volatile ligands supports potential applications for nasal CD36. Our present findings could promote future research aimed at understanding the mechanisms of fatty acid interactions with CD36.
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Antígenos CD36 , Ácidos Grasos , Animales , Antígenos CD36/metabolismo , Fluorescencia , Odorantes , Ácidos Láuricos , Mamíferos/metabolismoRESUMEN
The incidence of cancer-associated stroke has increased with the prolonged survival times of cancer patients. Recent genetic studies have led to progress in cancer therapeutics, but relationships between oncogenic mutations and stroke remain elusive. Here, we focused on the driver gene KRAS, which is the predominant RAS isoform mutated in multiple cancer types, in cancer associated stroke study. KRASG13D/- and parental human colorectal carcinoma HCT116 cells were inoculated into mice that were then subjected to a photochemically-induced thrombosis model to establish ischemic stroke. We found that cancer inoculation exacerbated neurological deficits after stroke. Moreover, mice inoculated with KRASG13D/- cells showed worse neurological deficits after stroke compared with mice inoculated with parental cells. Stroke promoted tumor growth, and the KRASG13D/- allele enhanced this growth. Brain RNA sequencing analysis and serum ELISA showed that chemokines and cytokines mediating pro-inflammatory responses were upregulated in mice inoculated with KRASG13D/- cells compared with those inoculated with parental cells. STAT3 phosphorylation was promoted following ischemic stroke in the KRASG13D/- group compared with in the parental group, and STAT3 inhibition significantly ameliorated stroke outcomes by mitigating microglia/macrophage polarization. Finally, we compared the prognosis and mortality of colorectal cancer patients with or without stroke onset between 1 January 2007 and 31 December 2020 using a hospital-based cancer registry and found that colorectal cancer patients with stroke onset within 3 months after cancer diagnosis had a worse prognosis. Our work suggests an interplay between KRAS and ischemic stroke that may offer insight into future treatments for cancer-associated stroke.
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Neoplasias Colorrectales , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Animales , Humanos , Ratones , Neoplasias Colorrectales/complicaciones , Neoplasias Colorrectales/genética , Mutación , Proteínas Proto-Oncogénicas p21(ras)/genética , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/genética , Células HCT116/metabolismoRESUMEN
Repulsive guidance molecule A (RGMa) was originally identified as a neuronal growth cone-collapsing factor. Previous reports have demonstrated the multifunctional roles of RGMa mediated by neogenin1. However, the pathogenic involvement of RGMa in amyotrophic lateral sclerosis (ALS) remains unclear. Here, we demonstrated that RGMa concentration was elevated in the cerebrospinal fluid of both patients with ALS and transgenic mice overexpressing the mutant human superoxide dismutase1 (mSOD1 mice). Treatment with humanized anti-RGMa monoclonal antibody ameliorated the clinical symptoms in mSOD1 mice. Histochemical analysis revealed that the anti-RGMa antibody significantly decreased mutant SOD1 protein accumulation in the motor neurons of mSOD1 mice via inhibition of actin depolymerization. In vitro analysis revealed that the anti-RGMa antibody inhibited the cellular uptake of the mutant SOD1 protein, presumably by reinforcing the neuronal actin barrier. Collectively, these data suggest that RGMa leads to the collapse of the neuronal actin barrier and promotes aberrant protein deposition, resulting in exacerbation of the ALS pathology.
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Esclerosis Amiotrófica Lateral , Animales , Humanos , Ratones , Actinas , Esclerosis Amiotrófica Lateral/genética , Esclerosis Amiotrófica Lateral/patología , Anticuerpos , Ratones Transgénicos , Neuronas Motoras/metabolismo , Superóxido Dismutasa/genética , Superóxido Dismutasa/metabolismo , Superóxido Dismutasa-1/genéticaRESUMEN
BACKGROUND: Data on the risk of cardiovascular-related mortality in patients with cancer are limited. METHODS AND RESULTS: This retrospective cohort study used data from the Osaka Cancer Registry and vital statistics in Japan between 1985 and 2013. The causes of death were investigated, and the risk of fatal heart disease was analyzed. Standardized mortality ratios were calculated to compare the risk of fatal heart disease between patients with cancer and the general population. Fine and Gray competing risk regression models were used to assess the risk of fatal heart disease among patients with cancer. In total, 682 886 patients with cancer were included in the analysis, and 335 635 patients died during the study period. Heart disease was the leading cause of noncancer deaths, with 10 686 deaths. Among the patients who died of heart disease, 5017 had ischemic heart disease, 3598 had heart failure, 356 had hypertensive disease, and 1715 had other heart diseases. The standardized mortality ratio for heart disease was 2.80 (95% CI, 2.74-2.85). The standardized mortality ratio for ischemic heart disease, heart failure, and hypertensive disease were 3.26 (95% CI, 3.17-3.35), 2.69 (95% CI, 2.60-2.78), and 5.97 (95% CI, 5.38-6.63), respectively. The risk of fatal heart disease increased over time after cancer diagnosis. Men were more likely to die of heart disease than women (subdistribution hazard ratio, 1.08 [95% CI, 1.02-1.16]). The risk of fatal heart disease among cancer survivors has decreased in recent years. CONCLUSIONS: Cancer survivors have a higher risk of fatal heart disease than the general population.
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Supervivientes de Cáncer , Insuficiencia Cardíaca , Hipertensión , Isquemia Miocárdica , Neoplasias , Masculino , Humanos , Femenino , Causas de Muerte , Estudios Retrospectivos , Japón/epidemiología , Factores de RiesgoRESUMEN
OBJECTS: The roles of mRNA and microRNA (miRNA) are well known in many diseases, including ischemic stroke; thus, integration analysis using mRNA and miRNA is important to elucidate pathogenesis. However, their contribution, especially that of miRNA-targeted mRNA, to the severity of acute ischemic stroke remains unclear. Therefore, we examined mRNA and miRNA integration analysis targeted for acute ischemic stroke to clarify the pathway related to acute stroke severity. MATERIAL AND METHODS: We performed Ingenuity Pathway Analysis (IPA) using RNA extracted from the whole blood of four healthy controls, six minor acute ischemic stroke patients (MS; National Institutes of Health Stroke Scale [NIHSS] < 8), and six severe acute ischemic stroke patients (SS; NIHSS ≥ 8) on admission. mRNA and miRNA were measured using RNA sequencing and RNA expression variation; canonical pathway analysis (CPA) and upstream regulator analyses were performed. RESULTS: Acute ischemic stroke patients demonstrated different RNA expressions to healthy controls. Compared to MS patients, in the SS patients, 1222 mRNA, 96 miRNA, and 935 miRNA-targeted mRNA expressions were identified among differentially expressed RNA expressions (p<0.05, |log2 fold change| >1.1). CPA by IPA using mRNAs or miRNA-targeted mRNAs showed that macrophage-stimulating protein (MSP)-recepteur d'origine nantais (RON) signaling was mostly activated in SS patients compared to in MS patients. In addition, upstream regulator analysis in IPA showed that most mRNAs located upstream are miRNAs. CONCLUSIONS: In severe acute stroke, integration of mRNA and microRNA analysis showed activated MSP-RON signaling in macrophages, and multiple miRNAs comprehensively controlled the overall pathophysiology of stroke.
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Background Limited data exist on the prognostic factors for patients with ischemic stroke and active cancer. Methods and Results We conducted a prospective, multicenter, observational study in Japan, including patients with acute ischemic stroke and active cancer, to investigate the prognostic factors. We followed up the patients for 1 year after stroke onset. The patients were divided into 2 groups according to cryptogenic stroke and known causes (small-vessel occlusion, large-artery atherosclerosis, cardioembolism, and other determined cause), and survival was compared. The hazard ratios (HRs) and 95% CIs for mortality were calculated using Cox regression models. We identified 135 eligible patients (39% women; median age, 75 years). Of these patients, 51% had distant metastasis. A total of 65 (48%) and 70 (52%) patients had cryptogenic stroke and known causes, respectively. Patients with cryptogenic stroke had significantly shorter survival than those with known causes (HR [95% CI], 3.11 [1.82-5.32]). The multivariable Cox regression analysis revealed that distant metastasis, plasma D-dimer levels, venous thromboembolism (either deep venous thrombosis or pulmonary embolism) complications at stroke onset were independent predictors of mortality after adjusting for potential confounders. Cryptogenic stroke was associated with prognosis in univariable analysis but was not significant in multivariable analysis. The plasma D-dimer levels stratified the prognosis of patients with ischemic stroke and active cancer. Conclusions The prognosis of patients with acute ischemic stroke and active cancer varied considerably depending on stroke mechanism, distant metastasis, and coagulation abnormalities. The present study confirmed that coagulation abnormalities were crucial in determining the prognosis of such patients.
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Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Neoplasias , Accidente Cerebrovascular , Humanos , Femenino , Anciano , Masculino , Accidente Cerebrovascular Isquémico/complicaciones , Estudios Prospectivos , Factores de Riesgo , Accidente Cerebrovascular/etiología , Neoplasias/complicaciones , Isquemia Encefálica/etiologíaRESUMEN
BACKGROUND: Although stimulation of Wnt/ß-catenin signaling is an important strategy to treat ischemic stroke, its signaling pathway has not been fully clarified yet. Recently, RSPO3 (R-spondin 3)/LGR4 (leucine-rich repeat-containing G protein-coupled receptor 4) signaling has resolved TLR4 (toll-like receptor 4)-induced inflammation in lung injury; however, whether this signal is critical in the ischemic brain remains unknown. Therefore, we investigated the role of RSPO3/LGR4 signaling in the ischemic brain. METHODS: BALB/c mice were exposed to permanent distal middle cerebral artery and common carotid artery occlusion. Temporal RSPO3 and LGR4 expressions were examined, and the mice were randomly assigned to receive vehicle or recombinant RSPO3. The underlying mechanisms were investigated using microglial cell lines and primary mixed glia-endothelia-neuron and primary neuronal cultures. RESULTS: In the ischemic brain, RSPO3 and LGR4 were expressed in endothelial cells and microglia/macrophages and neurons, respectively. Stimulation of RSPO3/LGR4 signaling by recombinant RSPO3 recovered neurological deficits with decreased Il1ß and iNOS mRNA on day 3 and increased Gap43 on day 9. In cultured cells, LGR4 was expressed in neuron and microglia, whereas RSPO3 promoted nuclear translocation of ß-catenin. Neuroprotective effects with reduced expression of inflammatory cytokines were observed in lipopolysaccharide-stimulated glia-endothelium-neuron cultures but not in glutamate-, CoCl2-, H2O2-, or oxygen glucose deprivation-stimulated neuronal cultures, indicating that RSPO3/LGR4 can protect neurons by regulating inflammatory cytokines. LGR4-Fc chimera, which was used to block endogenous RSPO3/LGR4 signaling, increased LPS-induced production of inflammatory cytokines, suggesting that endogenous RSPO3 suppresses inflammation. RSPO3 decreased TLR4-related inflammatory cytokine expression by decreasing TLR4 expression without affecting the M1/M2 phenotype. RSPO3 also inhibited TLR2- and TLR9-induced inflammation but not TLR7-induced inflammation, and promoted neurite outgrowth. CONCLUSIONS: RSPO3/LGR4 signaling plays a critical role in regulating TLR-induced inflammation and neurite outgrowth in the ischemic brain. Enhancing this signal will be a promising approach for treating ischemic stroke.
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Accidente Cerebrovascular Isquémico , beta Catenina , Animales , Ratones , beta Catenina/genética , beta Catenina/metabolismo , Encéfalo/metabolismo , Citocinas/metabolismo , Células Endoteliales/metabolismo , Peróxido de Hidrógeno , Inflamación , Leucina , Proyección Neuronal , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Transducción de Señal , Receptor Toll-Like 4/metabolismoRESUMEN
Background Immune cells play a vital role in the pathology of ischemic stroke. Neutrophils and polymorphonuclear myeloid-derived suppressor cells share a similar phenotype and have attracted increasing attention in immune regulation research, yet their dynamics in ischemic stroke remain elusive. Methods and Results Mice were randomly divided into 2 groups and intraperitoneally treated with anti-Ly6G (lymphocyte antigen 6 complex locus G) monoclonal antibody or saline. Distal middle cerebral artery occlusion and transient middle cerebral artery occlusion were applied to induce experimental stroke, and mice mortality was recorded until 28 days after stroke. Green fluorescent nissl staining was used to measure infarct volume. Cylinder and foot fault tests were used to evaluate neurological deficits. Immunofluorescence staining was conducted to confirm Ly6G neutralization and detect activated neutrophils and CD11b+Ly6G+ cells. Fluorescence-activated cell sorting was performed to evaluate polymorphonuclear myeloid-derived suppressor cell accumulation in brains and spleens after stroke. Anti-Ly6G antibody successfully depleted Ly6G expression in mice cortex but did not alter cortical physiological vasculature. Prophylactic anti-Ly6G antibody treatment ameliorated ischemic stroke outcomes in the subacute phase. Moreover, using immunofluorescence staining, we found that anti-Ly6G antibody suppressed activated neutrophil infiltration into parenchyma and decreased neutrophil extracellular trap formation in penumbra after stroke. Additionally, prophylactic anti-Ly6G antibody treatment reduced polymorphonuclear myeloid-derived suppressor cell accumulation in the ischemic hemisphere. Conclusions Our study suggested a protective effect of prophylactic anti-Ly6G antibody administration against ischemic stroke by reducing activated neutrophil infiltration and neutrophil extracellular trap formation in parenchyma and suppressing polymorphonuclear myeloid-derived suppressor cell accumulation in the brain. This study may provide a novel therapeutic approach for ischemic stroke.
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Accidente Cerebrovascular Isquémico , Células Supresoras de Origen Mieloide , Accidente Cerebrovascular , Ratones , Animales , Células Supresoras de Origen Mieloide/metabolismo , Células Supresoras de Origen Mieloide/patología , Neutrófilos/metabolismo , Accidente Cerebrovascular Isquémico/metabolismo , Infarto de la Arteria Cerebral Media/metabolismo , Accidente Cerebrovascular/metabolismo , Ratones Endogámicos C57BLRESUMEN
Blood-brain barrier (BBB) disruption contributes to brain injury and neurological impairment. Tight junctions (TJs) and cell-cell adhesion complexes develop between endothelial cells in the brain to establish and maintain the BBB. Occludin, the first transmembrane protein identified in TJs, has received intense research interest because numerous in vitro studies have suggested its importance in maintaining BBB integrity. However, its role in maintaining BBB integrity after ischemic stroke is less clear owing to the lack of in vivo evidence. This study aimed to investigate the dynamics and function of occludin across the acute and chronic phases after stroke using occludin-deficient mice. By photochemically induced thrombosis model, the expression of occludin was decreased in brain endothelial cells from ischemic lesions. The neurological function of occludin-deficient mice was continuously impaired compared to that of wild-type mice. BBB integrity evaluated by Evans blue and 0.5-kDa fluorescein in the acute phase and by 10-kDa fluorescein isothiocyanate-labeled dextran in the chronic phase was decreased to a greater extent after stroke in occludin-deficient mice. Furthermore, occludin-deficient mice showed decreased claudin-5 and neovascularization after stroke. Our study reveals that occludin plays an important role from the acute to the chronic phase after ischemic stroke in vivo.
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Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Animales , Ratones , Ocludina/genética , Proteínas de Uniones Estrechas , Barrera Hematoencefálica , Células Endoteliales , FluoresceínaRESUMEN
INTRODUCTION: The association between cancer survivors and stroke deaths remains unclear. We aimed to evaluate the risk of fatal stroke in patients with cancer. MATERIALS AND METHODS: This study was conducted using data from the Osaka Cancer Registry and vital statistics in Japan, collected from 1985 to 2013. We extracted patient data and investigated the causes of death. Standardized mortality ratios were calculated to compare the risk of stroke in patients with cancer to that in the general population. Poisson regression models were used to estimate the risk of stroke in patients with cancer and other cancer subgroups. Stroke types were used for risk stratification. RESULTS: We identified 688,473 eligible patients with cancer. The cohort contributed 2,668,126 person-years at risk. During the study period, 337,117 patients died; stroke was the cause of death in 5496 patients. Stroke types included cerebral infarction (3259), intracerebral hemorrhage (1539), subarachnoid hemorrhage (364), and other cerebrovascular diseases (334). The crude mortality rate from fatal stroke was 205.99 per 100,000 person-years. The standardized mortality ratio (95 % confidence interval) for fatal stroke was 1.75 (1.71-1.80). When stratified by stroke types, the ratios for cerebral infarction, intracerebral hemorrhage, and subarachnoid hemorrhage were 1.83 (1.76-1.89), 2.38 (2.26-2.50), and 2.28 (2.03-2.56), respectively. The risk of fatal stroke increased with time after cancer diagnosis. The multivariate Poisson regression model indicated that men were more likely to die of stroke than women. CONCLUSIONS: Cancer survivors have a higher risk of fatal stroke than the general population across all stroke types.
Asunto(s)
Supervivientes de Cáncer , Neoplasias , Accidente Cerebrovascular , Hemorragia Subaracnoidea , Masculino , Humanos , Femenino , Hemorragia Subaracnoidea/complicaciones , Japón/epidemiología , Accidente Cerebrovascular/complicaciones , Hemorragia Cerebral/epidemiología , Infarto Cerebral/etiología , Factores de Riesgo , Neoplasias/complicacionesRESUMEN
Mdmx and Mdm2 are two major suppressor factors for the tumor suppressor gene p53. In central nervous system, Mdmx suppresses the transcriptional activity of p53 and enhances the binding of Mdm2 to p53 for degradation. But Mdmx dynamics in cerebral infarction remained obscure. Here we investigated the role of Mdmx under ischemic conditions and evaluated the effects of our developed small-molecule Protein-Protein Interaction (PPI) inhibitors, K-181, on Mdmx-p53 interactions in vivo and in vitro. We found ischemic stroke decreased Mdmx expression with increased phosphorylation of Mdmx Serine 367, while Mdmx overexpression by AAV-Mdmx showed a neuroprotective effect on neurons. The PPI inhibitor, K-181 attenuated the neurological deficits by increasing Mdmx expression in post-stroke mice brain. Additionally, K-181 selectively inhibited HDAC6 activity and enhanced tubulin acetylation. Our findings clarified the dynamics of Mdmx in cerebral ischemia and provide a clue for the future pharmaceutic development of ischemic stroke.