RESUMEN
Derivatives of the Chinese traditional medicine indirubin have shown potential for the treatment of cancer through a range of mechanisms. This study investigates the impact of 6'-bromoindirubin-3'-acetoxime (BiA) on immunosuppressive mechanisms in glioblastoma (GBM) and evaluates the efficacy of a BiA nanoparticle formulation, PPRX-1701, in immunocompetent mouse GBM models. Transcriptomic studies reveal that BiA downregulates immune-related genes, including indoleamine 2,3-dioxygenase 1 (IDO1), a critical enzyme in the tryptophan-kynurenine-aryl hydrocarbon receptor (Trp-Kyn-AhR) immunosuppressive pathway in tumor cells. BiA blocks interferon-γ (IFNγ)-induced IDO1 protein expression in vitro and enhances T cell-mediated tumor cell killing in GBM stem-like cell co-culture models. PPRX-1701 reaches intracranial murine GBM and significantly improves survival in immunocompetent GBM models in vivo. Our results indicate that BiA improves survival in murine GBM models via effects on important immunotherapeutic targets in GBM and that it can be delivered efficiently via PPRX-1701, a nanoparticle injectable formulation of BiA.
Asunto(s)
Glioblastoma , Animales , Ratones , Glioblastoma/tratamiento farmacológico , Triptófano/farmacología , Quinurenina , Oximas/farmacología , Oximas/uso terapéuticoRESUMEN
Event-related brain potentials (ERPs) elicited by auditory stimuli unrelated to a current visual-cognitive task (i.e., task-irrelevant auditory probes) can be used to evaluate the level of mental workload. Towards the evaluation of workload in the shortest possible time, the present study with a multiple-stimulus paradigm (Takeda and Kimura, 2014, Int. J. Psychophysiol.) examined whether manipulating time intervals between probes could improve the temporal resolution in evaluating workload. Probes were presented in four interval conditions as a combination of two mean interval lengths [long (600 ms) vs. short (300 ms)] and two interval variabilities [variable (five levels) vs. fixed], while participants were performing a driving game at slow and fast speeds (i.e., imposing low and high workload, respectively). For each interval condition, the minimum data length required to obtain a significant difference in the amplitude of ERPs (i.e., auditory N1 and P2) between the slow and fast driving tasks was estimated. The N1 difference was significant in all four interval conditions but the required minimum data lengths to observe this difference did not greatly differ across the interval conditions (about 60-90 s). The P2 difference was significant only in the long-variable condition and the required minimum data length was about 120 s. These results suggest that, at least with a multiple-stimulus paradigm, manipulations of time intervals between probes did not greatly improve the temporal resolution in evaluating mental workload; at present, long-variable intervals would be optimal for evaluating mental workload in detail.
Asunto(s)
Electroencefalografía , Potenciales Evocados Auditivos , Estimulación Acústica , Encéfalo/fisiología , Mapeo Encefálico , Potenciales Evocados , Potenciales Evocados Auditivos/fisiología , Humanos , Tiempo de Reacción/fisiologíaRESUMEN
Event-related potentials elicited by tones generated by one's own discrete actions (e.g., button presses) are attenuated compared to those elicited by tones generated externally. The present study investigated whether ERP attenuation would occur when the timing or pitch of tones is modulated by continuous actions, as for such actions, a weak association between actions and their auditory consequences is assumed. In a modulation condition, participants modulated the time interval between tones (Experiment 1) or the pitch of tones (Experiment 2) by turning a steering wheel. In a listening condition, participants listened to the same tones as in the modulation condition without any action. The results revealed that the amplitude of N2 elicited by tones decreased in the modulation compared to listening conditions, consistently in the two experiments, suggesting relatively higher-order auditory processing can be mainly influenced by the prediction of action consequences when continuous actions modulate features of auditory stimuli.
Asunto(s)
Electroencefalografía , Potenciales Evocados Auditivos , Estimulación Acústica , Percepción Auditiva , Potenciales Evocados , HumanosRESUMEN
Aldehyde reductase encoded by the Akr1a gene catalyzes the NADPH-dependent reduction of a variety of aldehyde compounds, and it plays a role in the biosynthesis of ascorbic acid (AsA) by converting D-glucuronate to L-gulonate. Although supplementing drinking water with AsA (1.5 mg/mL) ameliorates the fertility of Akr1a-/- (KO) female mice, litter sizes in the KO mice are typically smaller than those for Akr1a+/+ (WT) mice, and about one-third of the neonates have a reduced stature. Half of the neonates in the smallest, developmentally retarded group died before weaning, and the remaining half (less than 6 g in weight) also barely grew to adulthood. While no difference was found in the number of fetuses between the KO and WT mice at 14.5-embryonic days, the sizes of the KO fetuses had already diverged. Among the organs of these retarded KO neonates at 30 d, the spleen and thymus were characteristically small. While an examination of spleen cells showed the normal proportion of immune cells, apoptotic cell death was increased in the thymus, which would lead to thymic atrophy in the retarded KO neonates. Plasma AsA levels were lower in the small neonates despite the fact that their mothers had received sufficient AsA supplementation, and the corticosterone levels were inversely higher compared to wild-type mice. Thus, insufficient AsA contents together with a defect in corticosterone metabolism might be the cause of the retarded growth of the AKR1A-deficient mice embryos and neonates.
Asunto(s)
Aldehído Reductasa/genética , Ácido Ascórbico/sangre , Corticosterona/sangre , Retardo del Crecimiento Fetal/genética , Animales , Animales Recién Nacidos , Recuento de Células Sanguíneas , Femenino , Retardo del Crecimiento Fetal/sangre , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , EmbarazoRESUMEN
Superoxide dismutase 1 (Sod1) plays pivotal roles in antioxidation via accelerating the conversion of superoxide anion radicals into hydrogen peroxide, thus inhibiting the subsequent radical chain reactions. While Sod1 deficient cells inevitably undergo death in culture conditions, Sod1-knockout (KO) mice show relatively mild phenotypes and live approximately two years. We hypothesized that the presence of abundant levels of ascorbic acid (AsA), which is naturally produced in mice, contributes to the elimination of reactive oxygen species (ROS) in Sod1-KO mice. To verify this hypothesis, we employed mice with a genetic ablation of aldehyde reductase (Akr1a), an enzyme that is involved in the biosynthesis of AsA, and established double knockout (DKO) mice that lack both Sod1 and Akr1a. Supplementation of AsA (1.5 mg/ml in drinking water) was required for the DKO mice to breed, and, upon terminating the AsA supplementation, they died within approximately two weeks regardless of age or gender. We explored the etiology of the death from pathophysiological standpoints in principal organs of the mice. Marked changes were observed in the lungs in the form of macroscopic damage after the AsA withdrawal. Histological and immunological analyses of the lungs indicated oxidative damage of tissue and activated immune responses. Thus, preferential oxidative injury that occurred in pulmonary tissues appeared to be primary cause of the death in the mice. These collective results suggest that the pivotal function of AsA in coping with ROS in vivo, is largely in pulmonary tissues that are exposed to a hyperoxygenic microenvironment.
Asunto(s)
Ácido Ascórbico , Superóxido Dismutasa , Animales , Pulmón , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Superóxido Dismutasa/genética , Superóxido Dismutasa-1/genéticaRESUMEN
The amplitude of event-related brain potentials (ERPs) elicited by task-irrelevant auditory probes decreases when more attentional resources are allocated to a visual task. This task-irrelevant probe technique is considered to be useful in assessing the degree of interest in a visual task, as well as task difficulty. The present study examined the amplitude of the N1 and P2 components elicited by task-irrelevant auditory probes during a driving task in a simulated environment. The analysis of ERPs showed that the N1 amplitude decreased when participants drove on the road course that had more frequent and sharper curves, whereas the P2 amplitude decreased when the road contained sharper curves, irrespective of curve frequency. Subjective ratings of driving pleasure and difficulty showed the same variation patterns as the N1 and P2 amplitudes, respectively. These results suggest that use of the task-irrelevant probe technique can assess the degree of driving pleasure and difficulty separately.
Asunto(s)
Atención/fisiología , Conducción de Automóvil/psicología , Potenciales Evocados/fisiología , Placer/fisiología , Estimulación Acústica , Adulto , Electroencefalografía , Femenino , Humanos , Masculino , Análisis y Desempeño de Tareas , Adulto JovenRESUMEN
A reliable neuroscientific technique for objectively estimating the degree of interest in a real environment is currently required in the research fields of neuroergonomics and neuroeconomics. Toward the development of such a technique, the present study explored electrophysiological measures that reflect an observer's interest in a nearly-real visual environment. Participants were asked to walk through a simulated shopping mall and the attractiveness of the shopping mall was manipulated by opening and closing the shutters of stores. During the walking task, participants were exposed to task-irrelevant auditory probes (two-stimulus oddball sequence). The results showed a smaller P2/early P3a component of task-irrelevant auditory event-related potentials and a larger lambda response of eye-fixation-related potentials in an interesting environment (i.e., open-shutter condition) than in a boring environment (i.e., closed-shutter condition); these findings can be reasonably explained by supposing that participants allocated more attentional resources to visual information in an interesting environment than in a boring environment, and thus residual attentional resources that could be allocated to task-irrelevant auditory probes were reduced. The P2/early P3a component and the lambda response may be useful measures of interest in a real visual environment.
Asunto(s)
Variación Contingente Negativa/fisiología , Ambiente , Potenciales Evocados Auditivos/fisiología , Interfaz Usuario-Computador , Caminata/fisiología , Estimulación Acústica , Adulto , Análisis de Varianza , Mapeo Encefálico , Electroencefalografía , Movimientos Oculares/fisiología , Humanos , Masculino , Tiempo de Reacción/fisiología , Factores de Tiempo , Adulto JovenRESUMEN
Due to the Great East Japan Earthquake on 11 March 2011 and the following long-term earthquake swarm, many people living in the earthquake-affected areas have developed mental stress, even though clinically-diagnosable symptoms may not be apparent. Concurrently, many unusual reports have emerged in which persons complain of abnormally increased sensitivity to sudden ambient sounds during their daily lives (e.g., the sound of the washing machine on spin cycle). By recording event-related potentials to various sudden ambient sounds from young adults living in the affected areas, we found that the level of earthquake-induced mental stress, as indexed by the hyperarousal symptoms of posttraumatic stress disorder, was positively related to the magnitude of P3a to sudden ambient sounds. These results reveal a strong relationship between mental stress and enhanced involuntary attentional orienting in a large majority of trauma-exposed people without diagnosable symptoms.
Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/etiología , Terremotos , Orientación/fisiología , Sonido/efectos adversos , Estrés Psicológico/complicaciones , Estrés Psicológico/etiología , Estimulación Acústica , Adulto , Electroencefalografía , Potenciales Evocados Auditivos/fisiología , Femenino , Humanos , Japón , Masculino , Psicoacústica , Adulto JovenRESUMEN
OBJECTIVES: The aim of this study was to determine whether diacylglycerol kinase (DGK) is involved in transplasmalemmal Ca²âº influx of platelets. METHODS: Effects of R59949, an inhibitor of diacylglycerol kinase, on intracellular Ca²âº concentration ([Ca²âº](i) ) and mRNA expression of DGK isozymes were investigated using washed human platelet suspensions. KEY FINDINGS: Thrombin-induced increase in [Ca²âº](i) was significantly inhibited by pretreatment of platelets with R59949, while thapsigargin-induced increase in [Ca²âº](i) was comparable in platelets with and without R59949 pretreatment. Thapsigargin-induced increase in [Ca²âº](i) was markedly attenuated in the presence of SKF-96365. In the presence of SKF-96365, thrombin-induced increase in [Ca²âº](i) was significantly attenuated, and additional treatment with R59949 caused a further decrease in [Ca²âº](i) . Pretreatment of platelets with 1-butanol significantly attenuated thrombin-induced increase in [Ca²âº](i) , while thrombin-induced increase in [Ca²âº](i) was augmented in the presence of propranolol. mRNA expression of DGK-α and DGK-γ, which are known to be inhibited by R59949, in platelets was confirmed by RT-PCR analysis. CONCLUSIONS: R59949 inhibited a store-depletion-insensitive component of transplasmalemmal Ca²âº entry induced by thrombin, while store-operated Ca²âº entry was not affected by R59949. The results of this study suggest that phosphatidic acid is involved in thrombin-induced Ca²âº influx of platelets.
Asunto(s)
Plaquetas/efectos de los fármacos , Calcio/metabolismo , Membrana Celular/efectos de los fármacos , Diacilglicerol Quinasa/metabolismo , Piperidinas/farmacología , Quinazolinonas/farmacología , Tapsigargina/farmacología , Trombina/farmacología , Plaquetas/metabolismo , Butanoles/farmacología , Bloqueadores de los Canales de Calcio/farmacología , Membrana Celular/metabolismo , Diacilglicerol Quinasa/antagonistas & inhibidores , Diacilglicerol Quinasa/genética , Hemostáticos/farmacología , Humanos , Imidazoles/farmacología , Ácidos Fosfatidicos/metabolismo , Extractos Vegetales/farmacología , Agregación Plaquetaria/efectos de los fármacos , Propranolol/farmacología , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Thapsia/químicaRESUMEN
"Flow" is a positive emotional state which typically occurs when a person perceives a balance between the challenges associated with a situation and his or her capabilities to accomplish these demands. While flow often occurs along with positive feelings and high introspective performance, only a few studies have investigated how it is associated with cognitive performance (i.e., objective performance). In the present study, we investigated the relationship between flow, emotions, and cognitive performance. A short nap (20 min) and bright light (>2,000 lux) techniques were used as experimental manipulations to enhance flow. Fifteen participants (31.3 ± 7.19 yr old) took part in four experimental conditions: rest, short nap, bright light, and nap and bright light. Pearson's correlation coefficients were calculated for flow and other indices using standardized data. Results showed that flow scores significantly increased after a short nap and under bright light exposure. The correlations between flow and reaction time were also significant. Flow was significantly associated with positive emotion and sleepiness. These results suggest that a short nap and bright light can be employed as a flow facilitator and that flow status can be used as an indicator in evaluating work efficiency and occupational mental health.
Asunto(s)
Atención/fisiología , Trastornos del Conocimiento , Cognición/fisiología , Fototerapia , Sueño/fisiología , Vigilia , Adulto , Análisis de Varianza , Emociones , Femenino , Indicadores de Salud , Humanos , Masculino , Psicometría , Análisis y Desempeño de TareasRESUMEN
We have previously cloned a glycosylphosphatidyl inositol (GPI)-anchored protein, designated GPI-80 that associated with integrin and may modulate leukocyte adherence and migration. Recent studies have shown that GPI-80 belongs to a Vanin family that is related to pantetheinase, but the regulatory function of GPI-80 in cell adherence is still unclear. To clarify the possible functions of GPI-80, we transfected GPI-80 cDNA into Chinese hamster ovary (CHO) cells and observed adherence and morphological changes. Adherence of GPI-80 transfectants was significantly decreased when signal strength for the cell adhesion is weak, and the cell spreading of the transfectants was strongly inhibited. This inhibitory effect of GPI-80 expression was largely canceled by GPI-80 shedding with phosphatidy-linositol-specific phospholipase C. Interestingly, spreading of GPI-80 transfectants was temporarily recovered from the round shape but not maintained by stimulation with known activators of beta1 integrins, phorbol myristate acetate and manganese ions. Taken together, these results suggest that the expression of GPI-80 on CHO cells can influence cell spreading in weak adhesive signal conditions via extracellular matrix molecules.
Asunto(s)
Células CHO/citología , Moléculas de Adhesión Celular/fisiología , Adhesión Celular/fisiología , Amidohidrolasas , Animales , Western Blotting , Moléculas de Adhesión Celular/genética , Cricetinae , Cricetulus , ADN Complementario , Femenino , Citometría de Flujo , Proteínas Ligadas a GPI , Hidrolasas , Fosfatidilinositol Diacilglicerol-Liasa/farmacología , Receptores de Superficie Celular/fisiología , TransfecciónRESUMEN
Inflammatory and/or autoimmune diseases like ulcerative colitis (UC) or Crohn's disease (CD) are debilitating chronic disorders that poorly respond to pharmacological interventions. Further, drug therapy has adverse effects that add to disease complications. The current thinking is that disorders like inflammatory bowel disease (IBD) reflect an over exuberant immune activation driven by cytokines including TNF-alpha. Major sources of cytokines include myeloid leukocytes (granulocytes, monocytes/macrophages), which in IBD are elevated with activation behavior and are found in vast numbers within the inflamed intestinal mucosa. Accordingly, myeloid cells should be the targets of therapy. Adacolumn is filled with cellulose acetate beads that selectively adsorb and deplete myeloid cells and a small fraction of lymphocytes (FcgammaR and complement receptors bearing cells). In one study, 20 steroid naive patients with moderate (n = 14) or severe (n = 6) UC according to Rachmilewitz despite 1.5-2.25 g/day of 5-aminosalicylic acid received 6 to 10 Adacolumn sessions at 2 sessions/week. Efficacy was assessed 1 week after the last session. The majority of patients responded to 6 sessions, 17 (85%) achieved remission. In 2 of the 3 non-responders, CAI was 8 and 12 in 1; all 3 had deep colonic ulcers at study initiation. Decreases were seen in total leukocytes (P = 0.003), % neutrophils (P = 0.003), % monocytes (P = 0.004), an increase in lymphocytes (P = 0.001), decreases in C-reactive protein (P = 0.0002), and rises in blood levels of soluble TNF-alpha receptors I (P = 0.0007), II (P = 0.0045). In a separate study, a case with very severe steroid refractory UC who received up to 11 sessions responded well and avoided colectomy. Further, myeloid cell purging with Adacolumn has been associated with the release of IL-1 receptor antagonist, suppression of TNF-alpha, IL-1beta, IL-6, IL-8, down-modulation of L-selectin and the chemokine receptor CXCR3. In conclusion, selective depletion of myeloid cells appears to induce anti-inflammatory effects and represents a non-pharmacological treatment for patients with active IBD. The treatment has a clear drug-sparing role. Changes in blood levels of inflammatory and anti-inflammatory factors are thought to contribute to the efficacy of this procedure.