RESUMEN
This study aimed to assess the effects of examination stress on salivary cortisol, immunoglobulin A (IgA), and chromogranin A (CgA) in nursing students. Saliva samples were collected from 15 healthy females before and immediately after the one-hour examination, and two hours after the examination. Salivary cortisol, IgA, and CgA concentrations were determined by enzyme-linked immunosorbent assay. Both IgA and CgA concentrations statistically increased immediately after the examination (P < 0.05) and decreased two hours after the examination. No significant differences were observed between before and after the examination in the salivary cortisol concentration. These findings suggest that the acute stress due to the examination is associated with raised salivary IgA and CgA, but not cortisol.
Asunto(s)
Cromogranina A/metabolismo , Evaluación Educacional , Hidrocortisona/metabolismo , Inmunoglobulina A/metabolismo , Saliva/química , Estrés Fisiológico/metabolismo , Estudiantes de Enfermería , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Psiconeuroinmunología , Saliva/metabolismo , Estudiantes de Enfermería/psicología , UniversidadesRESUMEN
The immune, endocrine and nervous systems are closely interrelated, which allows the organism to respond to different types of stress such as infection. Chronic infectious and inflammatory conditions are often accompanied by an impaired reproductive function. Leptin, a hormone produced by adipose tissue, exerts a regulatory function on the reproductive axis. It has homology with other proinflammatory cytokines and could be modified by lipopolysaccharide (LPS). Therefore, these studies were designed to investigate the effect of LPS administration on the neuroendocrine mechanisms involved in the regulation of the reproductive axis during sexual maturation. Fifteen- and 30-day-old female rats were injected with a single dose of LPS 250 microg/kg (i.p.) and then nitric oxide synthase (NOS) activity, hypothalamic excitatory/inhibitory amino acids and Gn-RH content, serum LH and leptin concentration were studied. In 15-day-old female rats LPS treatment did not modify hypothalamic inducible (iNOS) and constitutive (cNOS) NOS activity, Gn-RH, glutamate (GLU) and GABA content. Also serum LH and leptin levels were not modified. In 30-day-old rats LPS increased iNOS and cNOS activity (p < 0.001) and hypothalamic Gn-RH content (p < 0.001). At this age hypothalamic GABA content was significantly decreased (p < 0.001) without changes in GLU content, and serum LH (p < 0.001) and leptin (p < 0.0001) decreased significantly. In summary, current studies have demonstrated that LPS administration to 15- and 30-day-old female rats results in a different response of the hypothalamus-pituitary-gonadal axis and of the adipose tissue, demonstrating an ontogenic response of the immune-neuroendocrine system to LPS administration.
Asunto(s)
Infecciones Bacterianas/inmunología , Leptina/inmunología , Neuroinmunomodulación/inmunología , Sistemas Neurosecretores/inmunología , Reproducción/inmunología , Maduración Sexual/inmunología , Tejido Adiposo/inmunología , Tejido Adiposo/metabolismo , Envejecimiento/inmunología , Envejecimiento/metabolismo , Animales , Femenino , Ácido Glutámico/inmunología , Ácido Glutámico/metabolismo , Hormona Liberadora de Gonadotropina/inmunología , Hormona Liberadora de Gonadotropina/metabolismo , Sistema Hipotálamo-Hipofisario/inmunología , Sistema Hipotálamo-Hipofisario/metabolismo , Hipotálamo/inmunología , Hipotálamo/metabolismo , Mediadores de Inflamación/farmacología , Leptina/sangre , Lipopolisacáridos/farmacología , Hormona Luteinizante/sangre , Hormona Luteinizante/inmunología , Sistemas Neurosecretores/metabolismo , Sistemas Neurosecretores/fisiopatología , Óxido Nítrico Sintasa/inmunología , Óxido Nítrico Sintasa/metabolismo , Ratas , Ratas Wistar , Estrés Fisiológico/inmunología , Estrés Fisiológico/metabolismo , Estrés Fisiológico/fisiopatología , Regulación hacia Arriba/inmunología , Ácido gamma-Aminobutírico/inmunología , Ácido gamma-Aminobutírico/metabolismoRESUMEN
BACKGROUND: We designed and tested, in vitro, an adenoviral construct containing the feline interleukin-12 (IL-12) gene under control of the heat-inducible promoter HSP70B. This construct, AdhspfIL12, was used in a phase I trial in feline soft tissue sarcomas. During the course of our experiments, we noted that IL-12 was being produced in the transfected Crandell Feline Kidney (CrFK) cells under certain conditions even in the absence of hyperthermia. This observation was further explored to identify the cause of this unintended HSP70B induction. MATERIALS AND METHODS: We used real-time PCR as a sensitive method to quantitatively detect the presence of even small amounts of IL-12 mRNA. This served as a surrogate indicator of HSP70B induction. Various conditions were tested to induce the heat shock promoter, including nutritional deprivation, radiation and changes in pH. RESULTS: Nutritional stresses, specifically the absence of glucose and glutamine, could induce the heat shock promoter, thus, resulting in production of the downstream gene product. Other factors known to trigger the heat shock response, pH change, and reactive oxygen species production were also studied but were not found to contribute to heat shock promoter induction in our setting. CONCLUSIONS: The human heat shock promoter (HSP70B) is reported to be an efficient and tightly regulated promoter. We discovered, using sensitive real-time PCR techniques, that it can also be induced in response to cellular nutrient stresses. The pros and cons of this phenomenon and its implications for cancer gene therapy are discussed.
Asunto(s)
Terapia Genética/métodos , Proteínas HSP70 de Choque Térmico/genética , Interleucina-12/biosíntesis , Regiones Promotoras Genéticas , Estrés Fisiológico/metabolismo , Activación Transcripcional , Adenoviridae/genética , Animales , Antimitóticos/farmacología , Afidicolina/farmacología , Gatos , Línea Celular , Proliferación Celular , Medios de Cultivo/metabolismo , Terapia Genética/efectos adversos , Vectores Genéticos , Glucosa/deficiencia , Glutamina/deficiencia , Humanos , Concentración de Iones de Hidrógeno , Hipertermia Inducida , Interleucina-12/genética , Reacción en Cadena de la Polimerasa , ARN Mensajero/biosíntesis , Especies Reactivas de Oxígeno/metabolismo , Estrés Fisiológico/genética , Factores de Tiempo , Activación Transcripcional/efectos de los fármacos , TransfecciónRESUMEN
The survival of all organisms depends upon their ability to overcome stressful conditions, an ability that involves adaptive changes in cells and molecules. Findings from studies of animal models and human populations suggest that hormesis (beneficial effects of low levels of stress) is an effective means of protecting against many different diseases including diabetes, cardiovascular disease, cancers and neurodegenerative disorders. Such stress resistance mechanisms can be bolstered by diverse environmental factors including exercise, dietary restriction, cognitive stimulation and exposure to low levels of toxins. Some commonly used vitamins and dietary supplements may also induce beneficial stress responses. Several interrelated cellular signaling molecules are involved in the process of hormesis. Examples include the gases oxygen, carbon monoxide and nitric oxide, the neurotransmitter glutamate, the calcium ion and tumor necrosis factor. In each case low levels of these signaling molecules are beneficial and protect against disease, whereas high levels can cause the dysfunction and/or death of cells. The cellular and molecular mechanisms of hormesis are being revealed and include activation of growth factor signaling pathways, protein chaperones, cell survival genes and enzymes called sirtuins. Knowledge of hormesis mechanisms is leading to novel approaches for preventing and treating a range of human diseases.
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Adaptación Fisiológica , Inmunidad Innata/fisiología , Estrés Fisiológico/metabolismo , Xenobióticos/farmacología , Animales , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Homeostasis/fisiología , Humanos , Inmunidad Innata/efectos de los fármacos , Extractos Vegetales/metabolismo , Extractos Vegetales/farmacología , Estrés Fisiológico/fisiopatologíaRESUMEN
Tyrosine hydroxylase is the rate-limiting enzyme in the biosynthesis of the catecholamines. It has been reported that retinol (vitamin A) modulates tyrosine hydroxylase activity by increasing its expression through the activation of the nuclear retinoid receptors. In this study, we observed that retinol also leads to an acute activation of tyrosine hydroxylase in bovine adrenal chromaffin cells and this was shown to occur via two distinct non-genomic mechanisms. In the first mechanism, retinol induced an influx in extracellular calcium, activation of protein kinase C and serine40 phosphorylation, leading to tyrosine hydroxylase activation within 15 min. This effect then declined over time. The retinol-induced rise in intracellular calcium then led to a second slower mechanism; this involved an increase in reactive oxygen species, activation of extracellular signal-regulated kinase 1/2 and serine31 phosphorylation and the maintenance of tyrosine hydroxylase activation for up to 2 h. No effects were observed with retinoic acid. These results show that retinol activates tyrosine hydroxylase via two sequential non-genomic mechanisms, which have not previously been characterized. These mechanisms are likely to operate in vivo to facilitate the stress response, especially when vitamin supplements are taken or when retinol is used as a therapeutic agent.
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Médula Suprarrenal/metabolismo , Catecolaminas/biosíntesis , Células Cromafines/metabolismo , Serina/metabolismo , Tirosina 3-Monooxigenasa/metabolismo , Vitamina A/metabolismo , Médula Suprarrenal/citología , Secuencia de Aminoácidos/fisiología , Animales , Sitios de Unión , Calcio/metabolismo , Señalización del Calcio/efectos de los fármacos , Señalización del Calcio/fisiología , Bovinos , Células Cultivadas , Células Cromafines/efectos de los fármacos , Activación Enzimática/efectos de los fármacos , Activación Enzimática/fisiología , Quinasas MAP Reguladas por Señal Extracelular/efectos de los fármacos , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Fosforilación/efectos de los fármacos , Proteína Quinasa C/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Estrés Fisiológico/metabolismo , Estrés Fisiológico/fisiopatología , Tirosina 3-Monooxigenasa/química , Tirosina 3-Monooxigenasa/efectos de los fármacos , Regulación hacia Arriba/efectos de los fármacos , Regulación hacia Arriba/fisiología , Vitamina A/farmacologíaRESUMEN
Psychosocial stress, combined with mild dieting and moderate exercise, are observed in women seeking treatment for hypothalamic amenorrhea. Using female cynomolgus macaques, we previously reported that the same combination of mild stresses suppressed reproductive hormone secretion and menstrual cycles in some individuals (stress-sensitive, SS), but not in others (highly stress-resilient, HSR). Compared to HSR monkeys, SS monkeys exhibited lower oestradiol and progesterone levels at the midcycle peak and decreased gene expression in the central serotonergic system during nonstressed cycles. Because steroids and serotonin impinge upon the hypothalamic-pituitary-gonadal (HPG) axis, we hypothesised that the differences between SS and HSR monkeys in the sensitivity of the HPG axis to stress may ultimately manifest in differences in the gonadotrophin-releasing hormone (GnRH) system. GnRH in situ hybridisation and immunohistochemistry were performed with hypothalamic sections from SS and HSR animals, euthanised in the early follicular phase of a nonstressed menstrual cycle. Compared to HSR monkeys, SS monkeys exhibited a significantly higher number and density of GnRH cell bodies, as well as a higher number of soma with extremely robust expression of GnRH mRNA, but SS monkeys exhibited a lower density of immunostained GnRH fibres in the median eminence. We suggest that neuronal mechanisms involved in the control of GnRH synthesis, transport and release differ in SS compared to HSR animals.
Asunto(s)
Hormona Liberadora de Gonadotropina/genética , Hipotálamo/metabolismo , Macaca fascicularis/genética , Estrés Fisiológico/genética , Adaptación Biológica/genética , Animales , Femenino , Regulación de la Expresión Génica , Hormonas Esteroides Gonadales/sangre , Hormona Liberadora de Gonadotropina/metabolismo , Macaca fascicularis/sangre , Macaca fascicularis/metabolismo , Ciclo Menstrual/genética , Ciclo Menstrual/metabolismo , Neuronas/metabolismo , ARN Mensajero/metabolismo , Estrés Fisiológico/sangre , Estrés Fisiológico/metabolismoRESUMEN
In rats, dietary supplementation with the amino acid tyrosine (TYR) prevents depletion of central catecholamines observed during acute environmental stress. Concomitant changes in the animals' behavioral responses to stress suggest that TYR might have similar effects on central catecholamines and cognition in humans exposed to environmental stress. This study aimed to determine if severe cold exposure impairs human cognition and if dietary supplementation with TYR would ameliorate such deficits. Volunteers (N=19) completed three test sessions on different days (35 degrees C control/placebo, approximately 10 degrees C/placebo, approximately 10 degrees C/TYR) using a double-blind, within subjects design. During each session, volunteers completed two 90-minute water immersions and consumed a food bar (150 mg/kg TYR or placebo) before each immersion (total TYR 300 mg/kg). Cognitive performance, mood, and salivary cortisol were assessed. Cortisol was elevated in the cold (p<.01). Volunteers made fewer correct responses on a Match-to-Sample memory measure (p<.05) and reaction time (RT) and errors increased on a choice RT test (p<.01) in the cold. Self-reported tension (p<.01), depression (p<.05) and confusion (p<.01) also increased in the cold. When volunteers consumed TYR, correct responses increased on a Match-to-Sample memory measure (p<.05) and study time for the sample was shorter (p<.05), indicative of more rapid and accurate information processing. Finally, RT on the memory measure revealed a similar pattern across immersions for TYR and thermoneutral conditions, but not cold/placebo (p<.05). This study demonstrates cold exposure degrades cognitive performance and supplementation with TYR alleviates working memory decrements.
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Cognición/efectos de los fármacos , Memoria a Corto Plazo/efectos de los fármacos , Tiempo de Reacción/efectos de los fármacos , Estrés Fisiológico/metabolismo , Tirosina/metabolismo , Adaptación Fisiológica/efectos de los fármacos , Adolescente , Adulto , Análisis de Varianza , Temperatura Corporal , Cognición/fisiología , Frío , Suplementos Dietéticos , Aprendizaje Discriminativo/efectos de los fármacos , Aprendizaje Discriminativo/fisiología , Método Doble Ciego , Femenino , Humanos , Masculino , Memoria a Corto Plazo/fisiología , Tiempo de Reacción/fisiología , Valores de Referencia , Tirosina/farmacologíaRESUMEN
We compared the acid-base balance in broiler chickens provided diets containing 2 dietary electrolyte balances (DEB), and administered with either adrenocorticotropic hormone (ACTH) or saline solution. Diets were moderate (174 mEq/kg) or high (241 mEq/kg) DEB formulated by altering Na-K-Cl based on actual analysis. The experiment was designed as a split plot, with the main unit consisting of 4 treatments and the factorial treatment structure arranged in a completely randomized design. Osmotic pumps delivered 8 IU of ACTH in saline/kg of BW per d for 7 d, or the same saline volume as used in ACTH at 1 microL/h for 7 d was implanted on d 35. Venous blood samples were collected on d 35 before the pumps were implanted and on d 42 and 49. Birds fed the high DEB diet exhibited significantly higher Na(+) and Ca(2+) levels than birds provided the moderate DEB diet on d 35. Infusion of ACTH significantly increased (P < or = 0.05) hematocrit, hemoglobin, partial pressure of CO(2) (pCO(2)), corticosterone, osmolality, and HCO(3)(-) and reduced pH, BW, partial pressure of O(2) (pO(2)), and plasma concentrations of Na(+) and Cl(-) in both diets compared with the control group on d 42. Similarly, the ACTH treatment significantly increased hematocrit, hemoglobin, Ca(2+), corticosterone, and osmolality and reduced (P < or = 0.05) pO(2), glucose, and BW on d 49. The diet formulated for high DEB partially lowered pCO(2) on d 42. Significant DEB x ACTH interactions were observed for pCO(2) and pO(2) on d 49. However, there was a reduction in pO(2) along with a concomitant increase in erythropoiesis under the ACTH treatment for both diets, compared with the saline control, because of the increased need for O(2) to support gluconeogenic energy production. This adaptive response provided greater numbers of erythrocytes and thus a higher amount of circulating hemoglobin to deliver O(2) for metabolism. The diet formulated for high DEB partially attenuated the adaptive stress condition in broiler chickens.
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Equilibrio Ácido-Base/efectos de los fármacos , Equilibrio Ácido-Base/fisiología , Pollos/fisiología , Dieta/veterinaria , Electrólitos/farmacología , Estrés Fisiológico/veterinaria , Hormona Adrenocorticotrópica/toxicidad , Alimentación Animal , Animales , Suplementos Dietéticos , Masculino , Enfermedades de las Aves de Corral/inducido químicamente , Enfermedades de las Aves de Corral/metabolismo , Estrés Fisiológico/inducido químicamente , Estrés Fisiológico/metabolismoRESUMEN
OBJECTIVE: To investigate the changes of spontaneous and cognitive behavior, and cholinergic M receptors in the brain of mice subjected to chronic mild stress (CMS), and to determine the effect of Ning Shen Ling Granule (NSL) and dehydroepiandrosterone (DHEA) on them. METHODS: CMS model mice were established by applying stress every day for 3 consecutive weeks with 7 kinds of unforeseeable stress sources, and they were medicated for 1 week beginning at the 3rd week of modeling. The changes in behavior were determined by Morris Water Maze and spontaneous movement test, and M-receptor binding activity in cerebral cortex, hippocampus and hypothalamus were measured by radioactive ligand assay with 3H-QNB. RESULTS: (1) The spontaneous movement in CMS model mice was significantly reduced, with the latency for searching platform in Morris Water Maze obviously prolonged (P<0.01), and these abnormal changes in behavior were improved in those treated with NSL and DHEA. (2) The binding ability of M-receptor in cerebral cortex and hippocampus of CMS mice was significantly decreased as compared with those in the control group (P<0.05), but could be restored to the normal level after intervention with NSL or DHEA. CONCLUSION: The decline of spontaneous movement and spatial learning and memory ability could be induced in animals by chronic mild stress, and that may be related to the low activity of central cholinergic M-receptors. Both NSL and DHEA could effectively alleviate the above-mentioned changes.
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Cognición/efectos de los fármacos , Deshidroepiandrosterona/farmacología , Medicamentos Herbarios Chinos/farmacología , Estrés Fisiológico/psicología , Animales , Corteza Cerebral/metabolismo , Enfermedad Crónica , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Memoria/efectos de los fármacos , Ratones , Ratones Endogámicos , Movimiento/efectos de los fármacos , Quinuclidinil Bencilato/metabolismo , Receptores Muscarínicos/metabolismo , Índice de Severidad de la Enfermedad , Estrés Fisiológico/metabolismo , Estrés Fisiológico/fisiopatología , NataciónRESUMEN
Metal toxicity may be associated with increased rates of reactive oxygen species (ROS) generation within the central nervous system (CNS). Although the kidney is the main target organ for uranium (U) toxicity, this metal can also accumulate in brain. In this study, we investigated the modifications on endogenous antioxidant capacity and oxidative damage in several areas of the brain of U-exposed rats. Eight groups of adult male rats received uranyl acetate dihydrate (UAD) in the drinking water at 0, 10, 20, and 40 mg/kg/day for 3 months. Animals in four groups were concurrently subjected to restraint stress during 2h/day throughout the study. At the end of the experimental period, cortex, hippocampus and cerebellum were removed and processed to examine the following stress markers: reduced glutathione (GSH), oxidized glutathione (GSSG), glutathione reductase (GR), glutathione peroxidase (GPx), superoxide dismutase (SOD), catalase (CAT), thiobarbituric acid reactive substances (TBARS), as well as U concentrations. The results show that U significantly accumulated in hippocampus, cerebellum and cortex after 3 months of exposure. Moreover, UAD exposure promoted oxidative stress in these cerebral tissues. In cortex and cerebellum, TBARS levels were positively correlated with the U content, while in cerebellum GSSG and GSH levels were positively and negatively correlated, respectively, with U concentrations. In hippocampus, CAT and SOD activities were positively correlated with U concentration. The present results suggest that chronic oral exposure to UAD can cause progressive perturbations on physiological brain levels of oxidative stress markers. Although at the current UAD doses restraint scarcely showed additional adverse effects, its potential influence should not be underrated.
Asunto(s)
Cerebelo/efectos de los fármacos , Corteza Cerebral/efectos de los fármacos , Hipocampo/efectos de los fármacos , Estrés Fisiológico/metabolismo , Uranio/toxicidad , Animales , Catalasa/metabolismo , Cerebelo/metabolismo , Corteza Cerebral/metabolismo , Glutatión/metabolismo , Disulfuro de Glutatión/metabolismo , Glutatión Peroxidasa/metabolismo , Glutatión Reductasa/metabolismo , Hipocampo/metabolismo , Masculino , Ratas , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/metabolismo , Restricción Física , Superóxido Dismutasa/metabolismo , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo , Uranio/farmacocinéticaRESUMEN
The mouse ghrelin gene contains 5 exons (Ex), with Ex2-Ex5 encoding a 117 amino acid preproprotein that is processed to yield a 28 amino acid mature peptide. The current study examined if pituitary (PIT) and hypothalamus (HPT) ghrelin expression is up-regulated in response to fasting and down-regulated in obesity, as previously reported in the stomach. In the process of establishing a quantitative real-time RT-PCR system to accurately assess the changes in PIT and HPT ghrelin mRNA levels, we observed that primer sets located in Ex2 and Ex3 amplified a ghrelin transcript that contained the entire intron 2 (In2). Size and sequence analysis of RT-PCR products using multiple primer sets located throughout the ghrelin gene suggested that the In2-ghrelin variant contains Ex2 and Ex3, but lacks Ex1, Ex4, and Ex5. In2-ghrelin variant mRNA was not detected in stomach extracts, while expression levels were 10- and 50-fold greater than that of the native ghrelin transcript in the PIT and HPT respectively. In2-ghrelin variant mRNA levels increased in the PIT after 24 h fasting and decreased in the HPT and PIT of diet-induced obese mice. These changes may be due to the changes in circulating insulin or IGF-I, since both decreased In2-ghrelin variant expression in a mouse HPT cell line (N6) and in primary mouse PIT cell cultures. The fact that In2-ghrelin variant mRNA levels are dependent on energy intake in the PIT and HPT suggests that this transcript may encode a peptide important in coordinating the neuroendocrine response to metabolic stress.
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Regulación de la Expresión Génica , Hipotálamo/metabolismo , Hormonas Peptídicas/genética , Hipófisis/metabolismo , Estrés Fisiológico/metabolismo , Animales , Secuencia de Bases , Ayuno/metabolismo , Femenino , Ghrelina , Intrones , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Obesos , Datos de Secuencia Molecular , Obesidad/metabolismo , Hormonas Peptídicas/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
Arginine is a nonessential amino acid in the normal physiological state that becomes conditionally essential during periods of hypermetabolic stress. Recent literature supports the hypothesis that arginine plays an important role in the intermediary metabolism of the critically ill patient. Current critical care literature is conflicting on arginine use in the clinical setting, with some proposing it as a panacea, whereas others report it as poison. Multiple individual reports and at least 5 major meta-analyses using combinations of immune-modulating nutrients have reported mostly beneficial results, but few have evaluated the effects of arginine when given as a single supplemental nutrient. This review attempts to objectively analyze the literature and evaluate the potential role of arginine in the critical care setting.
Asunto(s)
Arginina/metabolismo , Arginina/uso terapéutico , Enfermedad Crítica , Estrés Fisiológico/tratamiento farmacológico , Estrés Fisiológico/metabolismo , Arginina/inmunología , Cuidados Críticos/métodos , Humanos , Estrés Fisiológico/inmunologíaRESUMEN
The purpose of this study is to examine the physiological effects of Shinrin-yoku (taking in the atmosphere of the forest). The subjects were 12 male students (22.8+/-1.4 yr). On the first day of the experiments, one group of 6 subjects was sent to a forest area, and the other group of 6 subjects was sent to a city area. On the second day, each group was sent to the opposite area for a cross check. In the forenoon, the subjects were asked to walk around their given area for 20 minutes. In the afternoon, they were asked to sit on chairs and watch the landscapes of their given area for 20 minutes. Cerebral activity in the prefrontal area and salivary cortisol were measured as physiological indices in the morning at the place of accommodation, before and after walking in the forest or city areas during the forenoon, and before and after watching the landscapes in the afternoon in the forest and city areas, and in the evening at the place of accommodation. The results indicated that cerebral activity in the prefrontal area of the forest area group was significantly lower than that of the group in the city area after walking; the concentration of salivary cortisol in the forest area group was significantly lower than that of the group in the city area before and after watching each landscape. The results of the physiological measurements show that Shinrin-yoku can effectively relax both people's body and spirit.
Asunto(s)
Ambiente , Hidrocortisona/metabolismo , Terapia por Relajación , Saliva/metabolismo , Estrés Fisiológico/terapia , Árboles , Adulto , Atmósfera , Humanos , Masculino , Psicofisiología , Estrés Fisiológico/metabolismo , Estrés Fisiológico/fisiopatología , CaminataRESUMEN
The physiological effects of "Shinrin-yoku" (taking in the atmosphere of the forest) were examined by investigating blood pressure, pulse rate, heart rate variability (HRV), salivary cortisol concentration, and immunoglobulin A concentration in saliva. Subjective feelings of being "comfortable", "calm", and "refreshed" were also assessed by questionnaire. The subjects were 12 male university students aged from 21 to 23 (mean+/-SD: 22.0+/-1.0). The physiological measurements were conducted six times, i.e., in the morning and evening before meals at the place of accommodation, before and after the subjects walked a predetermined course in the forest and city areas for 15 minutes, and before and after they sat still on a chair watching the scenery in the respective areas for 15 minutes. The findings were as follows. In the forest area compared to the city area, 1) blood pressure and pulse rate were significantly lower, and 2) the power of the HF component of the HRV tended to be higher and LF/(LF+HF) tended to be lower. Also, 3) salivary cortisol concentration was significantly lower in the forest area. These physiological responses suggest that sympathetic nervous activity was suppressed and parasympathetic nervous activity was enhanced in the forest area, and that "Shinrin-yoku" reduced stress levels. In the subjective evaluation, 4) "comfortable", "calm", and "refreshed" feelings were significantly higher in the forest area. The present study has, by conducting physiological investigations with subjective evaluations as supporting evidence, demonstrated the relaxing and stress-relieving effects of "Shinrin-yoku".
Asunto(s)
Hidrocortisona/metabolismo , Terapia por Relajación , Saliva/metabolismo , Estrés Fisiológico/terapia , Árboles , Adulto , Atmósfera , Presión Sanguínea , Ambiente , Frecuencia Cardíaca , Humanos , Japón , Masculino , Pulso Arterial , Estrés Fisiológico/metabolismo , Estrés Fisiológico/fisiopatología , Encuestas y Cuestionarios , CaminataRESUMEN
Chlamydomonas acidophila faces high heavy-metal concentrations in acidic mining lakes, where it is a dominant phytoplankton species. To investigate the importance of metals to C. acidophila in these lakes, we examined the response of growth, photosynthesis, cell structure, heat-shock protein (Hsp) accumulation, and metal adsorption after incubation in metal-rich lake water and artificial growth medium enriched with metals (Fe, Zn). Incubation in both metal-rich lake water and medium caused large decreases in photosystem II function (though no differences among lakes), but no decrease in growth rate (except for medium + Fe). Concentrations of small Hsps were higher in algae incubated in metal-rich lake-water than in metal-enriched medium, whereas Hsp60 and Hsp70A were either less or equally expressed. Cellular Zn and Fe contents were lower, and metals adsorbed to the cell surface were higher, in lake-water-incubated algae than in medium-grown cells. The results indicate that high Zn or Fe levels are likely not the main or only contributor to the low primary production in mining lakes, and multiple adaptations of C. acidophila (e.g., high Hsp levels, decreased metal accumulation) increase its tolerance to metals and permit survival under such adverse environmental conditions. Supposedly, the main stress factor present in the lake water is an interaction between low P and high Fe concentrations.
Asunto(s)
Adaptación Fisiológica , Chlamydomonas/efectos de los fármacos , Hierro/toxicidad , Estrés Fisiológico/inducido químicamente , Contaminantes Químicos del Agua/toxicidad , Zinc/toxicidad , Animales , Transporte Biológico , Chaperonina 60/metabolismo , Chlamydomonas/crecimiento & desarrollo , Chlamydomonas/metabolismo , Medios de Cultivo/química , Agua Dulce/química , Proteínas HSP70 de Choque Térmico/metabolismo , Proteínas de Choque Térmico Pequeñas/metabolismo , Concentración de Iones de Hidrógeno , Hierro/análisis , Fósforo/análisis , Fotosíntesis/efectos de los fármacos , Complejo de Proteína del Fotosistema II/metabolismo , Estrés Fisiológico/metabolismo , Estrés Fisiológico/fisiopatología , Factores de Tiempo , Contaminantes Químicos del Agua/análisis , Zinc/análisisRESUMEN
Cerebral hypometabolism, oxidative stress and beta-amyloid peptide (Abeta) accumulation are key pathological events in Alzheimer's disease (AD). Beta-secretase (BACE, i.e., BACE1), a prerequisite for Abeta genesis, is elevated in sporadic AD. Recent studies show BACE upregulation in experimental conditions likely associated with energy insufficiency and/or oxidative stress. We investigated the effect of sublethal doses of mitochondrial respiratory inhibitors and potential endogenous oxidative substances on BACE expression in vivo using the retina as a model. Retinas were analyzed biochemically and anatomically 48 h following intraocular applications of mitochondrial complex I, II and IV inhibitors including rotenone, 3-nitropropionic acid and sodium azide, and plaque-containing oxidants including Fe(3+) and Abeta42 fibrils (Abeta42f). All agents caused elevations of BACE proteins and beta-site amyloid precursor protein (APP) cleavage product, beta-CTF, in retinal lysates in a dose-dependant manner. BACE activity and Abeta40 levels were also increased in agent-treated retinas relative to vehicle controls. BACE immunoreactivity in normal adult rat retina was present mostly in the plexiform layers, indicating a localization of the enzyme to synaptic terminals. No apparent change in laminar or cellular distribution of BACE labeling was detected in the experimental retinas. However, signs of neuronal stress including glial activation were observed in agent-treated retinas especially in high dosage groups. Our data suggest that mitochondrial respiratory inhibition and oxidative stress facilitate BACE expression in vivo. In addition, plaque constituents such as Fe(3+) and Abeta42f may participate in a self-enforcing cycle of amyloidogenesis via BACE upregulation.
Asunto(s)
Secretasas de la Proteína Precursora del Amiloide/metabolismo , Ácido Aspártico Endopeptidasas/metabolismo , Respiración de la Célula/fisiología , Mitocondrias/metabolismo , Neuronas/enzimología , Estrés Oxidativo/fisiología , Retina/enzimología , Péptidos beta-Amiloides/metabolismo , Péptidos beta-Amiloides/toxicidad , Precursor de Proteína beta-Amiloide/efectos de los fármacos , Precursor de Proteína beta-Amiloide/metabolismo , Animales , Respiración de la Célula/efectos de los fármacos , Factor Neurotrófico Ciliar/efectos de los fármacos , Factor Neurotrófico Ciliar/metabolismo , Relación Dosis-Respuesta a Droga , Activación Enzimática/efectos de los fármacos , Activación Enzimática/fisiología , Hierro/toxicidad , Masculino , Mitocondrias/efectos de los fármacos , Oxidantes/toxicidad , Estrés Oxidativo/efectos de los fármacos , Fragmentos de Péptidos/metabolismo , Fragmentos de Péptidos/toxicidad , Placa Amiloide/metabolismo , Terminales Presinápticos/enzimología , Ratas , Ratas Sprague-Dawley , Estrés Fisiológico/metabolismo , Estrés Fisiológico/fisiopatología , Desacopladores/farmacología , Regulación hacia Arriba/efectos de los fármacos , Regulación hacia Arriba/fisiologíaRESUMEN
Using the Reverse Transcription-Polymerase Chain Reaction (RT-PCR) technique, the gonadotropin releasing-hormone (GnRH) mRNA and GnRH receptor (GnRH-R) mRNA were analyzed in the preoptic area (POA), anterior (AH) and ventromedial (VM) hypothalamus, stalk/median eminence (SME) and anterior pituitary gland (AP) of anestrous ewes subjected to short or prolonged footshock stimulation. No GnRH gene expression was detected in the SME and AP. The comparable levels of GnRH mRNA were found in the POA, AH and VM in control ewes. Short and prolonged footshock stimulation significantly increased GnRH mRNA in all analyzed tissue. The highest responses in GnRH mRNA to the short stress occurred in the POA whereas to the prolonged stress in the POA and VM. In non-stressed ewes the GnRH-R mRNA were detected in tissue continuum throughout the POA, AH, VM, SME and AP. The highest concentration of GnRH-R mRNA was detected in the SME. Short as well as prolonged stress stimuli caused an increase in GnRH-R mRNA levels in all analyzed tissue. The highest responses in GnRH-R mRNA expression were found in the VM. In spite of profound up-regulation of GnRH mRNA and GnRH-R mRNA under the short and prolonged stress conditions, the increase of luteinizing hormone (LH) secretion was noted only during acute stress. It is suggested that the increase of expression of GnRH and GnRH-R genes in anestrous ewes are not directly related to GnRH level and GnRH-R activity.
Asunto(s)
Hormona Liberadora de Gonadotropina/metabolismo , Hipotálamo/metabolismo , Adenohipófisis/metabolismo , Receptores LHRH/metabolismo , Estrés Fisiológico/metabolismo , Animales , Femenino , Hormona Liberadora de Gonadotropina/genética , Hormona Luteinizante/metabolismo , ARN Mensajero/metabolismo , Receptores LHRH/genética , OvinosRESUMEN
Heat shock protein (HSP)-70 is expressed in normal and stressed cells but is highly stress-inducible. Although leptin has long been suggested to be involved in the regulation of stress response, its interaction with the HSP-70 gene is still unknown, under both unstressed and stressed conditions. The present study has aimed to investigate the effect of leptin on HSP-70 gene expression in normal chicken liver, hypothalamus, and muscle. Continuous infusion of recombinant chicken leptin (8 mug/kg per hour) at a constant rate of 3 ml/h for 6 h in 3-week-old broiler chickens significantly (P < 0.05) decreased food intake and HSP-70 mRNA levels in liver and hypothalamus, but not in muscle. In an attempt to discriminate between the effect of leptin and of leptin-reduced food intake on HSP-70 gene expression, we also evaluated the effect of food deprivation on the same cellular responses in two broiler chicken lines genetically selected for low (LL) or high (FL) abdominal fat pad size. Food deprivation for 16 h did not affect HSP-70 gene expression in any of the studied tissues indicating that the effect of leptin was independent of the inhibition of food intake. Regardless of the nutritional status, HSP-70 mRNA levels were significantly (P < 0.05) higher in the hypothalamus of FL compared with LL chickens consistent with higher mRNA levels for hypothalamic corticotropin-releasing factor. To assess, whether the effects of leptin were direct or indirect, we carried out in vitro studies. Leptin treatments did not affect HSP-70 mRNA levels in a leghorn male hepatoma cell line or quail myoblast cell line suggesting that the effect of leptin on HSP-70 gene expression is mediated through the central nervous system. Furthermore, HSP-70 gene expression was gender-dependent with significantly (P < 0.05) higher levels in male than in female chickens.
Asunto(s)
Regulación de la Expresión Génica/efectos de los fármacos , Proteínas HSP70 de Choque Térmico/biosíntesis , Hipotálamo/metabolismo , Leptina/farmacología , Hígado/metabolismo , Caracteres Sexuales , Animales , Línea Celular Tumoral , Pollos , Hormona Liberadora de Corticotropina/biosíntesis , Ingestión de Alimentos/efectos de los fármacos , Femenino , Privación de Alimentos , Masculino , Músculo Esquelético/metabolismo , ARN Mensajero/biosíntesis , Estrés Fisiológico/metabolismo , Factores de TiempoRESUMEN
The objective of this work was to perform a parallel analysis of activation of the rat anterior hypothalamus cells as judged by c-Fos protein expression, and of the expression of interleukin-2 (IL-2) under different influences, i. e., mild stress (handling) and adaptation to it, and intranasal administration of saline and the peptides Vilon (Lys-Glu) and Epithalon (Ala-Glu-Asp-Gly). Changes in the counts of cells positive for c-Fos- and IL-2 proteins were studied in structures of the lateral (LHA) area, anterior (AHN), supraoptic (SO) and paraventricular (PVH) nuclei of Wistar rat hypothalamus. Quantity of the interleukin-2-positive and c-Fos-positive cells was calculated. The findings were: a negative correlation between the activation of cells and the amount of IL-2 in the cells in the hypothalamic structures under study, and the specific patterns of changes in the counts of cells positive for c-Fos and IL-2 under stress and adaptation to stress.
Asunto(s)
Regulación de la Expresión Génica , Hipotálamo/metabolismo , Interleucina-2/biosíntesis , Proteínas Proto-Oncogénicas c-fos/biosíntesis , Estrés Fisiológico/metabolismo , Animales , Dipéptidos/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Hipotálamo/patología , Masculino , Oligopéptidos/farmacología , Ratas , Ratas Wistar , Estrés Fisiológico/patologíaRESUMEN
Development of the hypothalamo-pituitary-adrenocortical (HPA) axis is marked by a diminution in stress responsiveness early in the postnatal period (days 4-14 in the rat). This 'stress hyporesponsive period' (SHRP) is thought to be at least in part centrally mediated. To investigate central mechanisms underlying the SHRP, this study assessed expression of glutamic acid decarboxylase (GAD) 67 in key stress-regulatory regions in the forebrain following acute stress with or without prior maternal deprivation. This isoform of GAD is known to be induced by stress in the adult and is believed to be a major contributor to production of the inhibitory neurotransmitter GABA under stimulated conditions. Expression of GAD67 mRNA was increased in the hippocampus, central amygdala and dorsomedial hypothalamus in pups tested early in the SHRP (day 6) or after its conclusion (day 18). In contrast, restraint caused a down-regulation of GAD67 mRNA in these structures when tested later in the SHRP (day 12). GAD67 mRNA expression was not affected by prior maternal deprivation in these regions. Reduced GABA production in the hippocampus (interneurons) is consistent with enhanced HPA axis inhibition, whereas reduced amygdalar expression predicts impaired stress excitation. Expression of GAD67 mRNA in the bed nucleus of the stria terminalis (BST) was minimally affected by acute restraint or maternal deprivation during the SHRP. However, older animals showed down-regulation of basal expression following maternal deprivation and substantial GAD67 mRNA up-regulation in both deprived and non-deprived groups following acute restraint. In contrast, non-responsiveness of the BST during the SHRP suggests either that BST GABA circuits are not actively engaged by stressors during this period or that circuits regulating BST GAD67 production are not yet in place. Overall, the data implicate forebrain GABA circuits in inhibition of HPA axis activity during the SHRP.