RESUMEN
Psychophysical stresses frequently increase sensitivity and response to pain, which is termed stress-induced hyperalgesia (SIH). However, the mechanism remains unknown. The subcortical areas such as medial preoptic area (MPO), dorsomedial nucleus of the hypothalamus (DMH), basolateral (BLA) and central nuclei of the amygdala (CeA), and the cortical areas such as insular (IC) and anterior cingulate cortices (ACC) play an important role in pain control via the descending pain modulatory system. In the present study we examined the expression of phosphorylated -cAMP-response element binding protein (pCREB) and the acetylation of histone H3 in these subcortical and cortical areas after repeated restraint stress to reveal changes in the subcortical and cortical areas that affect the function of descending pain modulatory system in the rats with SIH. The repeated restraint stress for 3 weeks induced a decrease in mechanical threshold in the rat hindpaw, an increase in the expression of pCREB in the MPO and an increase in the acetylation of histone H3 in the MPO, BLA and IC. The MPO was the only area that showed an increase in both the expression of pCREB and the acetylation of histone H3 among these examined areas after the repeated restraint stress. Furthermore, the number of pCREB-IR or acetylated histone H3-IR cells in the MPO was negatively correlated with the mechanical threshold. Together, our data represent the importance of the MPO among the subcortical and cortical areas that control descending pain modulatory system under the condition of SIH.
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Hiperalgesia/fisiopatología , Área Preóptica/fisiología , Estrés Psicológico/fisiopatología , Acetilación , Animales , Encéfalo/fisiología , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/análisis , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Histonas/metabolismo , Hiperalgesia/metabolismo , Hipotálamo/fisiología , Masculino , Dolor/fisiopatología , Manejo del Dolor , Umbral del Dolor/fisiología , Fosforilación , Área Preóptica/metabolismo , Ratas , Ratas Sprague-Dawley , Restricción FísicaRESUMEN
BACKGROUND In the recent years, there has been increasing interest in traditional Chinese medicine as a neuroprotective nutrient in the management of chronic neurodegenerative disease, such as diabetic cognitive decline. Astragalus polysacharin (APS), a Chinese herb extract, is a biologically active treatment for neurodegenerative diseases. Therefore, in the present study, we investigated the neuroprotective effects of APS (20 mg/kg) on diabetes-induced memory impairments in Sprague-Dawley (SD) rats and explored its underlying mechanisms of action. MATERIAL AND METHODS Thirty SD rats were randomly divided into a control group (CON group, n=10), a diabetic model (DM) group (n=10), and an APS group (n=10). We administered 55 mg/kg streptozotocin (STZ, Sigma) by intraperitoneal injection to induce a diabetic model. Food and water intake, body weight, and blood fasting plasma glucose (FPG) were measured. The Morris water maze test (MWM) was used to assess learning and memory ability, and we measured levels of N-methyl-D-aspartate receptor (NMDA), calcium/calmodulin-dependent protein kinase II (CaMKII), and cAMP response element-binding protein (CREB) in the hippocampus. RESULTS APS (20 mg/kg) administration decreased the rats' fasting plasma glucose (FPG) levels and body weight. APS (20 mg/kg) administration improved the cognitive performance of diabetes-induced rats in the Morris water maze test. APS (20 mg/kg) administration reduced the number of dead cells in the CA1 region of the hippocampus. Furthermore, APS (20 mg/kg) administration obviously upregulated the phosphorylation levels CREB, NMDA, and CaMK II. CONCLUSIONS These results suggest that APS has the neuroprotective effects, and it may be a candidate for treatment of neurodegenerative diseases such as diabetic cognitive impairment.
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Planta del Astrágalo/química , Memoria/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Animales , Planta del Astrágalo/metabolismo , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/análisis , Disfunción Cognitiva/metabolismo , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/análisis , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/fisiopatología , Medicamentos Herbarios Chinos/farmacología , Hipocampo/metabolismo , Hipocampo/fisiología , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Extractos Vegetales/farmacología , Raíces de Plantas/química , Ratas , Ratas Sprague-Dawley , Receptores de N-Metil-D-Aspartato/análisis , EstreptozocinaRESUMEN
AIMS: Cerebral ischemia reperfusion (I/R) is a neurovascular disease leading to cerebral damage. It was found that postmenopausal women are liable to more dangerous effects than men at same age in stroke. The objective of this study is to investigate the neuroprotective effect of zeranol against cerebral ischemia reperfusion in ovariectomized rats. MAIN METHODS: 36 female wistar rats divided in to 3 groups: sham group, I/R group (where I/R was induced 7â¯weeks after ovariectomy), zeranol group (0.5â¯mg/kg every 3â¯days for 5â¯weeks before I/R). Cerebral ischemia reperfusion (I/R) was performed by bilateral common carotid artery occlusion then de-ligated to restore blood flow. After 24â¯h of reperfusion, rats performed cylinder test to evaluate behavioral dysfunction followed by decapitation. Brain tissues were collected for biochemical measures such as oxidative stress marker malondialdehyde, antioxidant markers reduced glutathione, inflammatory markers (interleukin-1 beta, tumor necrosis factor alpha, and inducible nitric oxide synthase), matrix metalloproteinase-9, adenosine triphosphate, brain derived neurotrophic factor, glucose transporter-3, phosphorylated c-AMP response element binding protein and finally nissl staining for histopathological examination. KEY FINDINGS: The zeranol administered group showed a reversal of neuronal damage caused by ischemia evidenced by the decrease in MDA, IL-1ß, TNF-α, and MMP-9 levels, increase GSH, and ATP levels, decrease expression of iNOS in both regions cortex and hippocampus, increase protein level of p-CREB, GLUT-3 and BDNF, increase number of intact neuron cells in both regions and attenuated histological changes in both cortex and hippocampus regions. SIGNIFICANCE: Zeranol has neuroprotective potential against cerebral ischemia reperfusion in ovariectomized rats.
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Isquemia Encefálica/tratamiento farmacológico , Encéfalo/efectos de los fármacos , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Fitoestrógenos/uso terapéutico , Daño por Reperfusión/tratamiento farmacológico , Zeranol/uso terapéutico , Animales , Encéfalo/metabolismo , Encéfalo/patología , Encéfalo/fisiopatología , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patología , Isquemia Encefálica/fisiopatología , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/análisis , Femenino , Mediadores de Inflamación/análisis , Mediadores de Inflamación/metabolismo , Metaloproteinasa 9 de la Matriz/análisis , Metaloproteinasa 9 de la Matriz/metabolismo , Neurogénesis/efectos de los fármacos , Plasticidad Neuronal/efectos de los fármacos , Óxido Nítrico Sintasa de Tipo II/análisis , Óxido Nítrico Sintasa de Tipo II/metabolismo , Estrés Oxidativo/efectos de los fármacos , Ratas Wistar , Daño por Reperfusión/metabolismo , Daño por Reperfusión/patología , Daño por Reperfusión/fisiopatologíaRESUMEN
Objectives: This study evaluated the bioactive composition of tempeh products and examined the effects of tempeh on BV-2 microglial cell cytotoxicity, neurotrophic effects, and expression of inflammatory genes.Methods: Tempeh products included soybean fermented by Rhizopus, soybean fermented through cocultivation with Rhizopus and Lactobacillus, and red bean fermented through cocultivation with Rhizopus and Lactobacillus (RT-C). We analyzed the bioactive contents of tempeh extracts and evaluated the effects of tempeh water extract on lipopolysaccharide (LPS)-treated BV-2 cells.Results: The results showed that RT-C water extract had the highest concentrations of γ-aminobutyric acid (GABA) and anthocyanin. The tempeh water extracts, especially RT-C, reduced the formation of LPS-induced reactive oxygen species, downregulated the levels of nitric oxide synthase and phospho-cyclic-AMP response element-binding protein, and upregulated the expression of brain-derived neurotrophic factor (BDNF).Discussion: Our data demonstrate that RT-C has the highest concentrations of GABA and anthocyanin, more effectively reduces oxidative stress and inflammation, and increases the expression of BDNF in LPS-induced BV-2 cells.
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Lipopolisacáridos/farmacología , Microglía/efectos de los fármacos , Fármacos Neuroprotectores/administración & dosificación , Extractos Vegetales/farmacología , Alimentos de Soja , Animales , Antocianinas/análisis , Antocianinas/farmacología , Antiinflamatorios/farmacología , Antioxidantes/farmacología , Factor Neurotrófico Derivado del Encéfalo/análisis , Línea Celular , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/análisis , Fermentación , Lactobacillus/metabolismo , Ratones , Óxido Nítrico Sintasa de Tipo II/análisis , Extractos Vegetales/química , Rhizopus/metabolismo , Glycine max , Ácido gamma-Aminobutírico/análisis , Ácido gamma-Aminobutírico/farmacologíaRESUMEN
BACKGROUND: Acupuncture is an alternative therapy that is widely used to treat various neurodegenerative diseases and effectively improve cognitive and memory impairment. The aim of this study was to examine whether acupuncture stimulation at the Baihui (GV20) acupoint improves memory defects caused by scopolamine (SCO) administration in rats. We also investigated the effects of acupuncture stimulation at GV20 on the cholinergic system as well as the expression of brain-derived neurotrophic factor (BDNF) and cAMP-response element-binding protein (CREB) in the hippocampus. METHODS: SCO (2 mg/kg, i.p.) was administered to male rats once daily for 14 days. Acupuncture stimulation at GV20 was performed for 5 min before SCO injection. After inducing cognitive impairment via SCO administration, we conducted a passive avoidance test (PAT) and the Morris water maze (MWM) test to assess behavior. RESULTS: Acupuncture stimulation at GV20 improved memory impairment as measured by the PAT and reduced the escape latency for finding the platform in the MWM test. Acupuncture stimulation at GV20 significantly alleviated memory-associated decreases in the levels of choline acetyltransferase (ChAT), BDNF and CREB proteins in the hippocampus. Additionally, acupuncture stimulation at GV20 significantly restored the expression of choline transporter 1 (CHT1), vesicular acetylcholine transporter (VAChT), BDNF and CREB mRNA in the hippocampus. These results demonstrate that acupuncture stimulation at GV20 exerts significant neuroprotective effects against SCO-induced neuronal impairment and memory dysfunction in rats. CONCLUSIONS: These findings suggest that acupuncture stimulation at GV20 might be useful in various neurodegenerative diseases to improve cognitive functioning via stimulating cholinergic enzyme activities and regulating BDNF and CREB expression in the brain.
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Terapia por Acupuntura , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Trastornos del Conocimiento/inducido químicamente , Trastornos del Conocimiento/terapia , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Escopolamina/efectos adversos , Animales , Factor Neurotrófico Derivado del Encéfalo/análisis , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/análisis , Hipocampo/química , Masculino , Aprendizaje por Laberinto/fisiología , Ratas , Ratas Sprague-DawleyRESUMEN
We examined whether or not grape powder treatment ameliorates oxidative stress-induced anxiety-like behavior, memory impairment, and hypertension in rats. Oxidative stress in Sprague-Dawley rats was produced by using L-buthionine-(S,R)-sulfoximine (BSO). Four groups of rats were used: 1) control (C; injected with vehicle and provided with tap water), 2) grape powder-treated (GP; injected with vehicle and provided for 3 wk with 15 g/L grape powder dissolved in tap water), 3) BSO-treated [injected with BSO (300 mg/kg body weight), i.p. for 7 d and provided with tap water], and 4) BSO plus grape powder-treated (GP+BSO; injected with BSO and provided with grape powder-treated tap water). Anxiety-like behavior was significantly greater in BSO rats compared with C or GP rats (P < 0.05). Grape powder attenuated BSO-induced anxiety-like behavior in GP+BSO rats. BSO rats made significantly more errors in both short- and long-term memory tests compared with C or GP rats (P < 0.05), which was prevented in GP+BSO rats. Systolic and diastolic blood pressure was significantly greater in BSO rats compared with C or GP rats (P < 0.05), whereas grape powder prevented high blood pressure in GP+BSO rats. Furthermore, brain extracellular signal-regulated kinase-1/2 (ERK-1/2) was activated (P < 0.05), whereas levels of glyoxalase-1 (GLO-1), glutathione reductase-1 (GSR-1), calcium/calmodulin-dependent protein kinase type IV (CAMK-IV), cAMP response element-binding protein (CREB), and brain-derived neurotrophic factor (BDNF) were significantly less (P < 0.05) in BSO but not in GP+BSO rats compared with C or GP rats. We suggest that by regulating brain ERK-1/2, GLO-1, GSR-1, CAMK-IV, CREB, and BDNF levels, grape powder prevents oxidative stress-induced anxiety, memory impairment, and hypertension in rats.
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Ansiedad/prevención & control , Frutas/química , Hipertensión/prevención & control , Trastornos de la Memoria/prevención & control , Estrés Oxidativo/fisiología , Vitis/química , Animales , Ansiedad/etiología , Conducta Animal , Química Encefálica , Factor Neurotrófico Derivado del Encéfalo/análisis , Butionina Sulfoximina/administración & dosificación , Proteína Quinasa Tipo 4 Dependiente de Calcio Calmodulina/análisis , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/análisis , Suplementos Dietéticos , Modelos Animales de Enfermedad , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Alimentos en Conserva , Liofilización , Glutatión Reductasa/análisis , Hipertensión/etiología , Lactoilglutatión Liasa/análisis , Masculino , Trastornos de la Memoria/etiología , Polifenoles/administración & dosificación , Ratas , Ratas Sprague-DawleyRESUMEN
OBJECTIVE: To investigate the effect and molecular mechanism of Tiantai No.1, a compound Chinese herbal preparation, for the prevention and reduction of neurotoxicity induced by beta-amyloid peptides (Abeta) in vitro and its effects on nuclear factor-kappa B (NF-kappa B) and cAMP responsive element-binding protein (CREB) pathways using the gene transfection technique. METHODS: B104 neuronal cells were used to examine the effects of Tiantai No.1 on lowering the neurotoxicity induced by Abeta. The cells were pre-treated with Tiantai No.1 at doses of 50, 100, 150, or 200 micro g/mL respectively for 3 days and co-treated with Tiantai No.1 and beta-amyloid peptide1-40 (A beta 1-40, 10 micro mol/L) for 48 h or post-treated with Tiantai No.1 for 48 h after the cells were exposed to beta-amyloid peptides25-35 (A beta 25-35) for 8 h. In gene transfection assays, cells were treated with Tiantai No.1 at 50 micro g/mL and 150 micro g/mL for 5 days or co-treated with Tiantai No.1 and A beta 1-40 (5 micro mo/L) for 3 days after electroporation for the evaluation of NF-kappa B and CREB expression. RESULTS: Pre-treating and co-treating B104 neuronal cells with Tiantai No.1 lowered the neurotoxicity induced by Abeta, and post-treating with Tiantai No.1 reduced or blocked B104 neuronal apoptotic death induced by Abeta (P<0.05, P<0.01). With a dose-dependent relationship, the same treatments increased the expression of NF-kappa B or CREB in B104 neuronal cells (P<0.05, P<0.01). Meanwhile, Tiantai No.1 reduced A beta -40 induced inhibition on NF-kappa B expression (P<0.01). CONCLUSIONS: Tiantai No.1 can protect neurons against the neurotoxicity induced by Abeta. The neuroprotective mechanisms may be associated with the activation of NF-kappa B and cAMP cellular signal pathways.
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Péptidos beta-Amiloides , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/análisis , Medicamentos Herbarios Chinos/farmacología , FN-kappa B/análisis , Neuronas/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Células Cultivadas , Electroporación , Luciferasas , Microscopía Fluorescente , Ratas , TransfecciónRESUMEN
OBJECTIVE: To observe therapeutic effects and mechanisms at different acupoint groups for treatment of the depression rat. METHODS: Fifty Wistar rats were randomly divided into a normal group, a model group, a body acupoint group, a scalp acupoint group and a Fluoxetine hydrochloride group, 10 cases in each group. Depression rat model was established by using chronic unpredictable mild stress stimulation combined with lonely breeding for 21 days. EA (2 Hz, 1 mA, 20 min) was given at "Taichong" (LR 3), "Neiguan" (PC 6) and "Zusanli" (ST 36) in the body point group and "Baihui" (GV 20), "Yintang" (EX-HN 3), "Sishencong" (EX-HN 1) in the head point group, once daily, and Fluoxetine hydrochloride was given to the Fluoxetine hydrochloride group by intragastric administration, 2 mg/kg, once daily, for 21 days. Body weight of the rat was recorded, and the sucrose-intake test and forced swimming test were conducted one day before the experiment and on the 7th, 14th and 21st day of the experiment, and the open field test was conducted one day before the experiment and on the 21st day. p-CREB expression in the hippocampus of the rats were observed on the 22nd day. RESULTS: As compared with the model group, in the head point group and the Fluoxetine group, the crossing and rearing movement times, the relative volume of sucrose-intake and p-CREB expression in the hippocampus increased significantly, and the duration of immovability in forced swimming test shortened significantly (P<0.05). The relative volume of sucrose-intake increased and the duration of immovability in forced swimming test in the body point group significantly shortened (P<0.05), but the crossing and rearing movement times and p-CREB expression in the hippocampus did not insignificantly increase (P>0.05), with no significant differences among the treatment groups (P>0.05). CONCLUSION: EA at the head acupoints can improve behavioral activities and increase positive neuron number of p-CREB in the hippocampus of the depression rat, and selection of acupoints is of important role in treatment of depression.
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Proteína de Unión a Elemento de Respuesta al AMP Cíclico/análisis , Depresión/terapia , Electroacupuntura , Hipocampo/química , Puntos de Acupuntura , Animales , Peso Corporal , Depresión/metabolismo , Depresión/psicología , Masculino , Actividad Motora , Fosforilación , Distribución Aleatoria , Ratas , Ratas Wistar , NataciónRESUMEN
We recently showed that Nexrutine, a Phellodendron amurense bark extract, suppresses proliferation of prostate cancer cell lines and tumor development in the transgenic adenocarcinoma of mouse prostate (TRAMP) model. Our data also indicate that the anti-proliferative effects of Nexrutine are emediated in part by Akt and Cyclic AMP response element binding protein (CREB). Cyclooxygenase (Cox-2), a pro-inflammatory mediator, is a CREB target that induces prostaglandin E(2) (PGE(2)) and suppresses apoptosis. Treatment of LNCaP cells with Nexrutine reduced tumor necrosis factor alpha-induced enzymatic as well as promoter activities of Cox-2. Nexrutine also reduced the expression and promoter activity of Cox-2 in PC-3 cells that express high constitutive levels of Cox-2. Deletion analysis coupled with mutational analysis of the Cox-2 promoter identified CRE as being sufficient for mediating Nexrutine response. Immunohistochemical analysis of human prostate tumors show increased expression of CREB and DNA binding activity in high-grade tumors (three-fold higher in human prostate tumors compared to normal prostate; P = .01). We have identified CREB-mediated activation of Cox-2 as a potential signaling pathway in prostate cancer which can be blocked with a nontoxic, cost-effective dietary supplement like Nexrutine, demonstrating a prospective for development of Nexrutine for prostate cancer management.
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Proteína de Unión a Elemento de Respuesta al AMP Cíclico/fisiología , Ciclooxigenasa 2/metabolismo , Extractos Vegetales/farmacología , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/enzimología , Línea Celular Tumoral , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/análisis , Ciclooxigenasa 2/genética , ADN/metabolismo , Humanos , Inmunohistoquímica , Masculino , Regiones Promotoras Genéticas , Neoplasias de la Próstata/patología , Transducción de Señal , Factor de Necrosis Tumoral alfa/farmacologíaRESUMEN
The authors report the characterization of a novel cyclic adenosine monophosphate (cAMP)-responsive luciferase (Luc) reporter that exhibits optimal performance in high-throughput screens of agonist binding at G protein-coupled receptors (GPCRs). This reporter (RIP1-CRE-Luc) incorporates a nonpalindromic cAMP response element (CRE) originally identified within the 5' promoter of the rat insulin 1 gene (RIP1). When multimerized and fused to the coding sequence of firefly luciferase, the CRE of RIP1 allows for the efficient activation of luciferase expression by cAMP-elevating agents or by cAMP itself. Of primary importance is the demonstration that RIP1-CRE-Luc does not exhibit the relatively high levels of basal luciferase activity inherent to reporters incorporating the palindromic CRE first identified in the somatostatin gene promoter. Furthermore, studies of HEK cells expressing class II GPCRs for the cAMP-elevating hormones GLP-1, GIP, and glucagon demonstrate that RIP1-CRE-Luc affords a much wider dynamic range of activation upon exposure to agonist. Such properties of RIP1-CRE-Luc indicate its usefulness as a new and powerful tool for the identification of small-molecule compounds with receptor-stimulating actions or for the identification of constitutively active orphan receptors with cAMP-signaling properties.
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Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Diseño de Fármacos , Genes Reporteros , Luciferasas de Luciérnaga/metabolismo , Receptores Acoplados a Proteínas G/agonistas , Animales , Células CHO , Células COS , Línea Celular , Chlorocebus aethiops , Cricetinae , Cricetulus , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/análisis , Evaluación Preclínica de Medicamentos , Humanos , Riñón/citología , Reproducibilidad de los Resultados , TransfecciónRESUMEN
PURPOSE: Development of prostate cancer prevention strategies is an important priority to overcome high incidence, morbidity, and mortality. Recently, we showed that Nexrutine, an herbal extract, inhibits prostate cancer cell proliferation through modulation of Akt and cAMP-responsive element binding protein (CREB)-mediated signaling pathways. However, it is unknown if Nexrutine can be developed as a dietary supplement for the prevention of prostate cancer. In this study, we used the transgenic adenocarcinoma of mouse prostate (TRAMP) model to examine the ability of Nexrutine to protect TRAMP mice from developing prostate cancer. EXPERIMENTAL DESIGN: Eight-week-old TRAMP mice were fed with pelleted diet containing 300 and 600 mg/kg Nexrutine for 20 weeks. Efficacy of Nexrutine was evaluated by magnetic resonance imaging at 18 and 28 weeks of progression and histologic analysis of prostate tumor or tissue at the termination of the experiment. Tumor tissue was analyzed for modulation of various signaling molecules. RESULTS: We show that Nexrutine significantly suppressed palpable tumors and progression of cancer in the TRAMP model. Expression of total and phosphorylated Akt, CREB, and cyclin D1 was significantly reduced in prostate tissue from Nexrutine intervention group compared with tumors from control animals. Nexrutine also inhibited cyclin D1 transcriptional activity in androgen-independent PC-3 cells. Overexpression of kinase dead Akt mutant or phosphorylation-defective CREB inhibited cyclin D1 transcriptional activity. CONCLUSIONS: The current study shows that Nexrutine-mediated targeting of Akt/CREB-induced activation of cyclin D1 prevents the progression of prostate cancer. Expression of CREB and phosphorylated CREB increased in human prostate tumors compared with normal tissue, suggesting their potential use as prognostic markers.
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Adenocarcinoma/tratamiento farmacológico , Suplementos Dietéticos , Extractos Vegetales/administración & dosificación , Neoplasias de la Próstata/tratamiento farmacológico , Adenocarcinoma/patología , Adenocarcinoma/prevención & control , Animales , Proliferación Celular/efectos de los fármacos , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/análisis , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/antagonistas & inhibidores , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Ciclina D1/análisis , Ciclina D1/antagonistas & inhibidores , Ciclina D1/metabolismo , Modelos Animales de Enfermedad , Masculino , Ratones , Ratones Transgénicos , Fosforilación , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/prevención & control , Proteínas Proto-Oncogénicas c-akt/análisis , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-akt/metabolismo , Miembro 25 de Receptores de Factores de Necrosis Tumoral/genéticaRESUMEN
Mice exposed to various stresses, especially restrained-stress, revealed the anxiogenic effect detected by the light-dark test. Under this condition, a remarkable decrease in [35S]GTPgammaS binding to membranes from the prefrontal cortex, amygdala and hypothalamus of restrained-stress mice stimulated by the selective 5-HT1A receptor agonist 5-carboxamidotriptamine (5-CT) was clearly observed, whereas a significant increase in [35S]GTPgammaS binding stimulated by the 5-HT1A receptor agonist was clearly observed in the dorsal raphe nuclei (DRN) of restrained-stress mice. The immunohistochemical study showed a drastic reduction in phosphorylated-CREB-like immunoreactivity in the DRN of restrained-stress mice. Furthermore, we found a drastic reduction in myelin-associated glycoprotein (MAG)-like immunoreactivity (MAG-IR) in the DRN, amygdala and hypothalamus, indicating the direct suppression of synaptic transmission in these regions. It has been accepted that GSK3beta in the Wnt signal pathway plays an important role in various neuronal functions including apoptosis, clustering of synapsin I and early growth and axonal remodeling. In the present study, the increase in protein levels of GSK3beta and phosphorylated-GSK3beta to cytosol fractions of the amygdala was noted in restrained-stress mice. Taken together, these results suggest that restrained stress may directly affect the 5-HT1A receptor-regulated synaptic transmission in the brain, leading to the expression of the anxiogenic effect in mice. It is well known that various stresses induce intracellular oxidative stress. The present study was then undertaken to investigate the effect of the stimulation of 5-HT1A receptors on oxidative stress. Treatment with H2O2 caused the activation of caspase-3-positive cells and the reduction in levels of MAG-IR in the limbic neuron/glia cocultures as compared to medium alone. The stimulation of 5-HT1A receptor by 5-CT produced a dramatic protection against H2O2-triggered activation of caspase-3 and reduction in levels of MAG-IR. These results suggest that 5-HT1A receptors were involved in the modulation of anxiety and the understanding of molecular mechanisms of 5-HT1A receptor-related cascades may pave the way for new therapeutic strategies for affective disorders.
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Receptor de Serotonina 5-HT1A/fisiología , Estrés Psicológico/fisiopatología , Amígdala del Cerebelo/química , Animales , Ansiedad/metabolismo , Western Blotting , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/análisis , Femenino , Proteína GAP-43/análisis , Guanosina 5'-O-(3-Tiotrifosfato)/metabolismo , Hipotálamo/química , Inmunohistoquímica , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos ICR , Glicoproteína Asociada a Mielina/análisis , Corteza Prefrontal/química , Serotonina/análogos & derivados , Serotonina/farmacologíaRESUMEN
On the day of birth, a surge in testicular testosterone release in male rats is critical for sexual differentiation of the brain. Steroid hormones function by binding to intracellular steroid receptors and altering gene expression; however, little is known about the signal transduction pathways altered as a consequence of steroid hormone action in developing brain. We investigated whether the increase in testosterone at birth alters the phosphorylation of CREB, a major signal transduction protein. Adjacent brain sections from male and female pups were immunocytochemically stained for serine(133) phosphorylated CREB (pCREB) or total CREB on the day of birth. Males had more pCREB-immunoreactive positive cells than females in the medial preoptic area, ventromedial nucleus of the hypothalamus, the arcuate nucleus, and the CA1 region of the hippocampus, but not in two thalamic nuclei. There was no sex difference in total CREB immunoreactive cell number. To determine if the sex difference in pCREB persisted 24 h after birth and whether the difference was due to testosterone, newborn female pups were injected with 100 microg of testosterone propionate, and male and control female pups were injected with vehicle. Twenty-four hours later, adjacent brain sections were immunocytochemically stained for either pCREB or CREB. We found that males and testosterone-treated females had more pCREB in the ventromedial nucleus of the hypothalamus contrasted to control females. There were no group differences in pCREB or CREB in any other area examined. These results indicate that some of the effects of testosterone in developing brain occur via pathways associated with the phosphorylation of CREB.
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Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Hipotálamo/metabolismo , Caracteres Sexuales , Animales , Animales Recién Nacidos , Anticuerpos , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/análisis , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/inmunología , Estrógenos/metabolismo , Femenino , Hipotálamo/crecimiento & desarrollo , Masculino , Fosforilación , Embarazo , Ratas , Testosterona/metabolismoRESUMEN
In order to delimit the supra-brainstem structures that are activated during the sleep-waking cycle, we have examined c-fos immunoreactivity in four groups of polygraphically recorded cats killed after 3 h of prolonged waking (W), slow-wave sleep (SWS), or paradoxical sleep (PS), following microinjection of muscimol (a gamma-aminobutyric acid, GABA agonist) into the periaqueductal grey matter and adjacent areas [Sastre et al. (1996), Neuroscience, 74, 415-426]. Our results demonstrate that there was a direct relationship between a significant increase in c-fos labelling and the amount of PS in the laterodorsalis tegmenti in the pons, supramamillary nucleus, septum, hippocampus, gyrus cingulate, amygdala, stria terminalis and the accumbens nuclei. Moreover, in all these structures, the number of Fos-like immunoreactive neurons in the PS group was significantly higher (three to 30-fold) than in the SWS and W groups. We suggest that the dense expression of the immediate-early gene c-fos in the rhinencephalon and striatum may be considered as a tonic component of PS at the molecular level and that, during PS, the rhinencephalon and striatum are the main targets of an excitatory system originating in the pons.
Asunto(s)
Cuerpo Estriado/metabolismo , Vías Olfatorias/metabolismo , Proteínas Proto-Oncogénicas c-fos/biosíntesis , Sueño REM/fisiología , Vigilia/fisiología , Animales , Gatos , Corteza Cerebral/química , Corteza Cerebral/citología , Corteza Cerebral/metabolismo , Cuerpo Estriado/química , Cuerpo Estriado/citología , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/análisis , Proteínas de Unión al ADN/análisis , Femenino , Agonistas del GABA/farmacología , Genes Inmediatos-Precoces/fisiología , Hipotálamo/química , Hipotálamo/citología , Hipotálamo/metabolismo , Sistema Límbico/química , Sistema Límbico/citología , Sistema Límbico/metabolismo , Masculino , Microinyecciones , Muscimol/farmacología , Vías Nerviosas , Vías Olfatorias/química , Vías Olfatorias/citología , Sustancia Gris Periacueductal/química , Sustancia Gris Periacueductal/citología , Sustancia Gris Periacueductal/metabolismo , Puente/química , Puente/citología , Puente/metabolismo , Proteínas Proto-Oncogénicas c-fos/análisis , Sueño/efectos de los fármacos , Sueño/fisiología , Sueño REM/efectos de los fármacos , Tálamo/química , Tálamo/citología , Tálamo/metabolismo , Factores de Transcripción/análisis , Vigilia/efectos de los fármacosRESUMEN
Apoptosis may play an important role in atherogenesis. Oxidized low-density lipoprotein (oxLDL) promotes apoptosis in the arterial wall in addition to several other proatherogenic effects. Tocopherol supplements have been suggested to protect against coronary heart disease (CHD) in epidemiological studies. The effects of oxLDL and alpha- and gamma-tocopherol on apoptotic signaling pathways are poorly understood. Thus, the goal of the study was to investigate these pathways in the presence of copper-oxidized LDL and tocopherols in human coronary smooth muscle cells (SMC). We showed that oxLDL-mediated apoptosis, assessed by DNA fragmentation, terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) assay, and caspase activation stimulated several transcription factors and proapoptotic dynamic movements of the Bcl-2 family proteins through the mitogen-activated protein kinase (MAPK) and Jun kinase pathways. alpha-Tocopherol and gamma-tocopherol significantly reduced these molecular events and cell death effectors caspase-3 and -8. Under our experimental conditions, alpha-tocopherol was significantly more effective than gamma-tocopherol, and oxLDL-mediated apoptosis increased c-Jun, cyclic AMP-responsive element-binding, Ets-like element kinase-dependent 7, and activating transcription factor-2 proteins as well as nuclear activity of the activated protein-1 complex in human coronary SMC. Moreover, our results demonstrate that tocopherols may exert their antiatherogenic effects at least in part via reduction of the MAPK and JunK cascade together with a protective profile of apoptotic genes of the Bcl-2 family. These data are consistent with the beneficial effects of tocopherols on atherogenesis seen in experimental studies and on CHD in epidemiological surveys.
Asunto(s)
Apoptosis , Lipoproteínas LDL/farmacología , Músculo Liso Vascular/efectos de los fármacos , Transducción de Señal , Vitamina E/farmacología , Adulto , Células Cultivadas , Vasos Coronarios/citología , Vasos Coronarios/efectos de los fármacos , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/análisis , Humanos , Masculino , Proteínas Quinasas Activadas por Mitógenos/análisis , Músculo Liso Vascular/citología , Músculo Liso Vascular/metabolismo , Proteínas/análisis , Proteínas Proto-Oncogénicas c-bcl-2/análisis , Proteínas Proto-Oncogénicas c-jun/análisis , Transducción de Señal/fisiologíaRESUMEN
The coactivator CBP has been proposed to stimulate the expression of certain signal-dependent genes via its association with RNA polymerase II complexes. Here we show that complex formation between CBP and RNA polymerase II requires RNA helicase A (RHA), a nuclear DNA/RNA helicase that is related to the Drosophila male dosage compensation factor mle. In transient transfection assays, RHA was found to cooperate with CBP in mediating target gene activation via the CAMP responsive factor CREB. As a mutation in RHA that compromised its helicase activity correspondingly reduced CREB-dependent transcription, we propose that RHA may induce local changes in chromatin structure that promote engagement of the transcriptional apparatus on signal responsive promoters.