Iron-deficient diet induces distinct protein profile related to energy metabolism in the striatum and hippocampus of adult rats.

Iron deficiency is a public health problem that affects all age groups. Its main consequence is anemia, but it can also affect cognitive functions. Although the negative effects of iron deficiency on cognitive function have been extensively described, the underlying mechanism has not been fully investigated. Thus, to gain an unbiased insight into the effects of iron deficiency (ID) on discrete brain regions, we performed a proteomic analysis of the striatum and hippocampus of adult rats subjected to an iron restricted (IR) diets for 30 days. We found that an IR diet caused major alterations in proteins related to glycolysis and lipid catabolism in the striatum. In the hippocampus, a larger portion of proteins related to oxidative phosphorylation and neurodegenerative diseases were altered. These alterations in the striatum and hippocampus occurred without a reduction in local iron levels, although there was a drastic reduction in liver iron and ferritin. Moreover, the IR group showed higher fasting glycaemia than the control group. These results suggest that brain iron content is preserved during acute iron deficiency, but the alterations of other systemic metabolites such as glucose may trigger distinct metabolic adaptations in each brain region. Abnormal energy metabolism precedes and persists in many neurological disorders. Thus, altered energy metabolism can be one of the mechanisms by which iron deficiency affects cognitive functions.

Sleep deprivation regulates availability of PrPC and Aß peptides which can impair interaction between PrPC and laminin and neuronal plasticity.

PrPC is a glycoprotein capable to interact with several molecules and mediates diverse signaling pathways. Among numerous ligands, laminin (LN) is known to promote neurite outgrowth and memory consolidation, while amyloid-beta oligomers (Aßo) trigger synaptic dysfunction. In both pathways, mGluR1 is recruited as co-receptor. The involvement of PrPC /mGluR1 in these opposite functions suggests that this complex is a key element in the regulation of synaptic activity. Considering that sleep-wake cycle is important for synaptic homeostasis, we aimed to investigate how sleep deprivation affects the expression of PrPC and its ligands, laminin, Aßo, and mGluR1, a multicomplex that can interfere with neuronal plasticity. To address this question, hippocampi of control (CT) and sleep deprived (SD) C57BL/6 mice were collected at two time points of circadian period (13 hr and 21 hr). We observed that sleep deprivation reduced PrPC and mGluR1 levels with higher effect in active state (21 hr). Sleep deprivation also caused accumulation of Aß peptides in rest period (13 hr), while laminin levels were not affected. In vitro binding assay showed that Aßo can compete with LN for PrPC binding. The influence of Aßo was also observed in neuritogenesis. LN alone promoted longer neurite outgrowth than non-treated cells in both Prnp+/+ and Prnp0/0 genotypes. Aßo alone did not show any effects, but when added together with LN, it attenuated the effects of LN only in Prnp+/+ cells. Altogether, our findings indicate that sleep deprivation regulates the availability of PrPC and Aß peptides, and based on our in vitro assays, these alterations induced by sleep deprivation can negatively affect LN-PrPC interaction, which is known to play roles in neuronal plasticity.

Anxiolytic and panicolytic-like effects of environmental enrichment seem to be modulated by serotonin neurons located in the dorsal subnucleus of the dorsal raphe.

In a previous study, we showed that exposure of rats to a one-week environmental enrichment (EE) protocol decreases elevated T-maze (ETM) avoidance responses, an anxiolytic-like effect, without altering escape reactions, in clinical terms related to panic disorder. These anxiolytic-like effects were followed by decreased delta FosB-immunoreactivity (delta FosB-ir) in the cingulate cortex, dorsolateral and intermediate lateral septum, hippocampus (cornus of Ammon), anterior and dorsomedial hypothalamus, medial and basolateral amygdala and ventral region of the dorsal raphe nucleus. The purpose of the present study was to further investigate behavioral and neurophysiological alterations induced by EE exposure. For that, in a first experiment we verified if increasing the time of exposure to the same EE protocol used in our previous study (from one to two weeks) altered male Wistar rats' ETM escape responses. All animals were tested in an open field, immediately after the ETM, for locomotor activity assessment. Since anxiety and panic-related reactions have been associated to the functioning of specific subnuclei of the dorsal raphe nucleus (DR), we also evaluated delta FosB-ir in serotonergic cells of DR regions. At last, we analyzed plasma corticosterone levels in animals submitted to EE and to standard housing. Results showed that a two-week exposure to EE decreases both ETM avoidance and escape reactions, inducing anxiolytic and panicolytic-like effects, respectively. There was also a significant decrease in the number of double staining neurons in the midrostral region of the dorsal subnucleus of the dorsal raphe. No changes in corticosterone levels, however, were observed. These results contribute to a better understanding of the effects of EE on anxiety and panic-related responses.

Chronic corticosterone increases ΔFOSB and CRFR1 immunoreactivity in brain regions that modulate aversive conditioning.

Previous studies showed that chronic treatment with corticosterone facilitates elevated T-maze (ETM) inhibitory avoidance and a step-down avoidance task, responses that have been used to investigate aversive conditioning and memory processes. On the other hand, chronic corticosterone does not alter ETM escape from the open arms. The purpose of the present study was to further investigate the effects of chronic corticosterone treatment (200 mg pellets, 21-day release) in an animal model of anxiety that does not involve aversive conditioning: the light/dark transition model. We also investigated the pattern of ΔFosB immunoreactivity (ΔFosB-ir) in different brain regions. To examine how treatment with chronic corticosterone interferes with CRFR1 expression we measured CRFR1 in the same brain structures that exhibited increased ΔFosB-ir. Results showed that chronic treatment with corticosterone did not alter behavioral measurements performed in the light/dark transition model. On the other hand, ΔFosB-ir was increased in several structures that modulate aversive conditioning: the cingulate cortex, the ventro and dorsolateral septum, the amygdala, the paraventricular, dorsomedial and ventromedial hypothalamus, the periaqueductal grey matter, the dorsal raphe, and the median raphe nucleus. Chronic treatment with corticosterone also increased CRFR1-immunoreactivity in the ventrolateral septum, central amygdala, dorsomedial hypothalamus, ventral region of the dorsal raphe and median raphe. These results contribute to a better understanding of the behavioral and neurobiological alterations induced by chronic exposure to glucocorticoids.

Environmental enrichment decreases avoidance responses in the elevated T-maze and delta FosB immunoreactivity in anxiety-related brain regions.

Environmental enrichment (EE) is an animal management technique, which seems to improve adaptation to the experimental conditions of housing in laboratory animals. Previous studies have pointed to different beneficial effects of the procedure in the treatment of several disorders, including psychiatric conditions such as depression. The anxiolytic effects induced by EE, on the other hand, are not as clear. In fact, it has been proposed that EE acts as a mild stressor agent. To better understand the relationship of EE with anxiety-related responses, the present study exposed rats to one week of EE and subsequently tested these animals in the inhibitory avoidance and escape tasks of the elevated T-maze (ETM). In clinical terms, these responses have been respectively related to generalized anxiety and panic disorder. All animals were tested in an open field, immediately after the ETM, for locomotor activity assessment. Additionally, analysis of delta FosB protein immunoreactivity (FosB-ir) was used to map areas activated by EE exposure and plasma corticosterone measurements were performed. The results obtained demonstrate that exposure to EE for one week impaired avoidance responses, an anxiolytic-like effect, without altering escape reactions. Also, in animals submitted to the avoidance task EE exposure decreased FosB-ir in the cingulate cortex, dorsolateral and intermediate lateral septum, hippocampus (cornus of Ammon), anterior and dorsomedial hypothalamus, medial and basolateral amygdala and ventral region of the dorsal raphe nucleus. Although no behavioral differences were observed in animals submitted to the escape task, EE exposure also decreased FosB-ir in the cingulate cortex, hippocampus (dentate gyrus), lateral amygdala, paraventricular, anterior and ventromedial hypothalamus, dorsomedial periaqueductal gray and ventral and dorsal region of the dorsal raphe. No changes in corticosterone levels, however, were observed. These results contribute to a better understanding of the effects of EE on anxiety.

Sleep deprivation induces pathological changes in rat masticatory muscles: Role of Toll like signaling pathway and atrophy.

The aim of this study was to evaluate the Toll like signaling pathway and atrophy after sleep deprivation (SD) in rat masticatory muscles: masseter and temporal. A total of 24 animals was distributed into three groups: Control group (CTL, n = 8), subjected to SD for 96 h (SD96, n = 8) and subjected to SD for 96 h more 96 h of sleep recovery (SD96 + R, n = 8). Histopathological analysis revealed the presence of acute inflammatory cells, congested vessels, fibrosis, and high cellularity in the skeletal muscle fibers from masseter and temporal submitted to SD. These morphological alterations were not observed in the control group since neither inflammatory cells nor congested vessels were observed to this group. In the group SD96 + R, the absence of inflammation was noticed to the masseter only. In this group, COX-2 and TNF-alpha downregulation were detected when comparing to control group. MyD88 and pIKK decreased in SD96 and SD96 + R groups being pNFKBp50 downregulatated in SD96 + R. MyD88 expression increased in rats submitted to SD96 and SD96 + R in temporal when compared to control group. On the other hand, pIKK decreased the protein expression in groups SD96 and SD96 + R while pNFKBp50 showed a decreased protein expression in group SD96 only. The activation of atrophy by means of MAFbx upregulation was detected in temporal muscle in SD96 and SD96 + R when compared to control. In summary, our results show that SD is able to induce morphological alterations in rat masticatory muscles. Toll like signaling pathway and atrophy play important roles in ethiopathogenesis induced by SD, being dependent of skeletal muscle type.

High-Intensity Interval Training Attenuates Insulin Resistance Induced by Sleep Deprivation in Healthy Males.

Introduction: Sleep deprivation can impair several physiological systems and recently, new evidence has pointed to the relationship between a lack of sleep and carbohydrate metabolism, consequently resulting in insulin resistance. To minimize this effect, High-Intensity Interval Training (HIIT) is emerging as a potential strategy. Objective: The aim of this study was to investigate the effects of HIIT on insulin resistance induced by sleep deprivation. Method: Eleven healthy male volunteers were recruited, aged 18-35 years, who declared taking 7-8 h sleep per night. All volunteers were submitted to four different conditions: a single night of regular sleep (RS condition), 24 h of total sleep deprivation (SD condition), HIIT training followed by regular sleep (HIIT+RS condition), and HIIT training followed by 24 h of total sleep deprivation (HIIT+SD condition). They performed six training sessions over 2 weeks and each session consisted of 8-12 × 60 s intervals at 100% of peak power output. In each experimental condition, tests for glucose, insulin, cortisol, free fatty acids, and insulin sensitivity, measured by oral glucose tolerance test (OGTT), were performed. Results: Sleep deprivation increased glycaemia and insulin levels, as well as the area under the curve. Furthermore, an increase in free fatty acids concentrations and basal metabolism was observed. There were no differences in the concentrations of cortisol. However, HIIT before 24 h of sleep deprivation attenuated the increase of glucose, insulin, and free fatty acids. Conclusion: Twenty-four hours of sleep deprivation resulted in acute insulin resistance. However, HIIT is an effective strategy to minimize the deleterious effects promoted by this condition.

Iron-Restricted Diet Affects Brain Ferritin Levels, Dopamine Metabolism and Cellular Prion Protein in a Region-Specific Manner.

Iron is an essential micronutrient for several physiological functions, including the regulation of dopaminergic neurotransmission. On the other hand, both iron, and dopamine can affect the folding and aggregation of proteins related with neurodegenerative diseases, such as cellular prion protein (PrPC) and α-synuclein, suggesting that deregulation of iron homeostasis and the consequential disturbance of dopamine metabolism can be a risk factor for conformational diseases. These proteins, in turn, are known to participate in the regulation of iron and dopamine metabolism. In this study, we evaluated the effects of dietary iron restriction on brain ferritin levels, dopamine metabolism, and the expression levels of PrPC and α-synuclein. To achieve this goal, C57BL/6 mice were fed with iron restricted diet (IR) or with normal diet (CTL) for 1 month. IR reduced iron and ferritin levels in liver. Ferritin reduction was also observed in the hippocampus. However, in the striatum of IR group, ferritin level was increased, suggesting that under iron-deficient condition, each brain area might acquire distinct capacity to store iron. Increased lipid peroxidation was observed only in hippocampus of IR group, where ferritin level was reduced. IR also generated discrete results regarding dopamine metabolism of distinct brain regions: in striatum, the level of dopamine metabolites (DOPAC and HVA) was reduced; in prefrontal cortex, only HVA was increased along with the enhanced MAO-A activity; in hippocampus, no alterations were observed. PrPC levels were increased only in the striatum of IR group, where ferritin level was also increased. PrPC is known to play roles in iron uptake. Thus, the increase of PrPC in striatum of IR group might be related to the increased ferritin level. α-synuclein was not altered in any regions. Abnormal accumulation of ferritin, increased MAO-A activity or lipid peroxidation are molecular features observed in several neurological disorders. Our findings show that nutritional iron deficiency produces these molecular alterations in a region-specific manner and provide new insight into the variety of molecular pathways that can lead to distinct neurological symptoms upon iron deficiency. Thus, adequate iron supplementation is essential for brain health and prevention of neurological diseases.

Increased Dietary Leucine Reduces Doxorubicin-Associated Cardiac Dysfunction in Rats.

Cardiotoxicity is one of the most significant adverse effects of the oncologic treatment with doxorubicin, which is responsible for a substantial morbid and mortality. The occurrence of heart failure with ventricular dysfunction may lead to severe cardiomyopathy and ultimately to death. Studies have focused on the effects of leucine supplementation as a strategy to minimize or revert the clinical condition of induced proteolysis by several clinical onsets. However, the impact of leucine supplementation in heart failure induced by doxorubicin is unknown. Therefore, the objective of this work is to evaluate the effects of leucine supplementation on the cardiotoxicity in the heart of rats treated with doxorubicin. Rats treated with a 7.5 mg/kg cumulative dose of doxorubicin for 14 days presented a dilatation of the left ventricle (LV), and a reduction of the ejection fraction (FE). The 5% supplementation of leucine in the rats' food prevented the malfunctioning of the LV when administered with doxorubicin. Some alterations in the extracellular matrix remodeling were confirmed by the increase of collagen fibers in the doxorubicin group, which did not increase when the treatment was associated with leucine supplementation. Leucine attenuates heart failure in this experimental model with doxorubicin. Such protection is followed by the maintenance of interstitial collagen fibers.

Affective responses after different intensities of exercise in patients with traumatic brain injury.

BACKGROUND: Patients with traumatic brain injury (TBI) usually have mood and anxiety symptoms secondary to their brain injury. Exercise may be a cost-effective intervention for the regulation of the affective responses of this population. However, there are no studies evaluating the effects of exercise or the optimal intensity of exercise for this clinical group. METHODS: Twelve male patients with moderate or severe TBI [mean age of 31.83 and SD of 9.53] and 12 age- and gender-matched healthy volunteers [mean age of 30.58 and SD of 9.53] participated in two sessions of exercise of high and moderate-intensity. Anxiety and mood was evaluated, and subjective assessment of experience pre- and post-exercise was assessed. A mixed between and within-subjects general linear model (GLM) analysis was conducted to compare groups [TBI, control] over condition [baseline, session 1, session 2] allowing for group by condition interaction to be determined. Planned comparisons were also conducted to test study hypotheses. RESULTS: Although no group by condition interaction was observed, planned comparisons indicated that baseline differences between patients and controls in anxiety (Cohens' d = 1.80), tension (d = 1.31), depression (d = 1.18), anger (d = 1.08), confusion (d = 1.70), psychological distress (d = 1.28), and physical symptoms (d = 1.42) disappear after one session of exercise, independently of the intensity of exercise. CONCLUSION: A single-section of exercise, regardless of exercise intensity, had a positive effect on the affective responses of patients with TBI both by increasing positive valence feelings and decreasing negative ones. Exercise can be an easily accessible intervention that may alleviate depressive symptoms related to brain injury.

Nonalcoholic fatty liver disease decrease in obese adolescents after multidisciplinary therapy.

BACKGROUND: Despite the increasing prevalence of nonalcoholic fatty liver disease, its pathogenesis and clinical significance remain poorly defined and there is no ideal treatment. OBJECTIVE: The aim of this study was to assess the short-term (12-week) multidisciplinary therapy on visceral adiposity and nonalcoholic fatty liver disease control. METHODS: We evaluated and compared the distribution of visceral adiposity and nonalcoholic fatty liver disease, by ultrasonography, in 73 post-puberty obese participants (17.01+/-1.6 years old; body mass index 36.54+/-2.86 kg/m), submitted to a multidisciplinary treatment without medications, at the beginning and after 12 weeks of intervention. Descriptive and one-way analysis of variance, and paired t-test were performed. RESULTS: The results indicated that after intervention the adolescents had a significant reduction in visceral adiposity (4.05+/-1.55 to 3.37+/-1.44) and nonalcoholic fatty liver disease prevalence (from 52 to 29% on the right side and from 48 to 29% on the left side). It is a positive result because nonalcoholic fatty liver disease can progress to cirrhosis, even in children and adolescents. CONCLUSIONS: The short-term treatment suggests a profound impact on the control of obesity-related co-morbidities in young people.

O estresse físico e a dependência de exercício físico / Physical stress and physical exercise dependence

O objetivo do presente estudo foi verificar os escores referentes à escala de dependência de exercício, qualidade de vida, bem como os escores indicativos de humor em atletas de corrida de aventura (CA). Participaram deste estudo 17 atletas de ambos os gêneros com histórico de prática da modalidade de pelo menos três anos, com experiência em provas nacionais e internacionais e que figuram nas primeiras posições do ranking brasileiro. A média (± desvio-padrão) da idade, altura, massa corporal, índice de massa corpórea (IMC) e consumo de oxigênio foram: 31,11 ± 6,30 anos; 1,73 ± 0,07cm; 70,75 ± 7,96kg; 23,48 ± 1,48kg/m² e 58,70 ± 6,63ml.min¹.kg¹, respectivamente. Os voluntários responderam aos seguintes questionários: Escala de Dependência de Exercício (EDE), Idate Traço e Estado, Profile of Mood States (POMS), SF-36 Pesquisa em Saúde e Questionário de Padrão Social. Os resultados revelaram que os escores observados na EDE foram indicativos de dependência de exercício; já os questionários de humor revelaram ansiedade moderada, enquanto o POMS não detectou escores indicativos de distúrbios de humor. Quanto à qualidade de vida, a média das oito dimensões referentes ao questionário SF-36 se mostrou acima de 85 por cento, sugerindo que, apesar de haver dependência de exercício, parece que esse fato não foi capaz de promover alterações significativas no estado de humor e na qualidade de vida. Esses dados sugerem que atletas de CA apresentam dependência de exercício não associada aos distúrbios de humor.

The aim of this study was to verify the referring scores of exercise dependence, quality of life as well as the mood indicators in adventure race (AR) athletes. 17 athletes of both sexes participated in the study and all had a history of three years in this modality, with national and international experience, and figured in the first positions in the Brazilian ranking. The age, height, weight, body mass index (BMI) and oxygen uptake averages ± standard deviations were: 31.11 ± 6.30 years; 1.73 ± 0.07 cm; 70.75 ± 7.96 kg; 23.48 ± 1.48 wt/ht² and 58.70 ± 6.63 ml.min-1.kg-1, respectively. The volunteers were given the following questionnaires: Exercise Dependency Scale (EDE), Idate Trait and State, Profile of Mood States (POMS), SF-36 Health Research and Social Patterns Questionnaire. The results showed that scores in EDE indicated exercise dependence, and the mood questionnaires revealed moderate anxiety, while the POMS did not detect any indicative scores of mood disorders. Concerning the quality of life, the average of 8 dimensions of the SF-36 was higher than 85 percent, suggesting that although there was exercise dependence, this fact alone did not promote significant alterations in mood and quality of life. Thus, our data suggested that athletes of AR have exercise dependence not associated to mood disorders.

El objetivo del presente estudio ha sido el de verificar los escores referentes a la escala de dependencia de ejercicio, calidad de vida, así como los escores indicativos de humor en atletas de Carrera de Aventura (CA). Participaron de este estudio 17 atletas de ambos géneros con histórico de práctica de la modalidad de por lo menos tres años, con experiencia en pruebas nacionales e internacionales y que figuran en las primeras posiciones del ranking brasileño. La media (± desvío padrón) de edad, altura, masa corporal, índice de masa corpórea (IMC) y consumo de oxígeno fueron: 31,11 ± 6,30 años; 1,73 ± 0,07 cm; 70,75 ± 7,96 kg; 23,48 ± 1,48 kg/m² y 58,70 ± 6,63 ml.min-1.kg-1, respectivamente. Los voluntarios respondieron a los siguientes cuestionarios: Escala de Dependencia de Ejercicio (EDE), "Idate Traço" y Estado, Profile of Mood States (POMS), SF-36 Investigación e Salud y Cuestionario de Padrón Social. Los resultados revelaron que los escores observados en la EDE fueron indicativos de dependencia de ejercicio, mientras que los cuestionarios de humor revelaron ansiedad moderada, entretanto el POMS no detectó escores indicativos de disturbios de humor. En relación a la calidad de vida, la media de las 8 dimensiones referentes al cuestionario SF-36 se mostró por encima de 85 por ciento, lo que sugiere que a pesar de haber dependencia de ejercicio, parece que ese hecho no fue capaz de promover alteraciones significativas en el estado de humor y en la calidad de vida. Nuestros datos sugieren que atletas de CA presentan dependencia de ejercicio no asociada a los disturbios de humor.

Tratamento multidisciplinar reduz o tecido adiposo visceral, leptina, grelina e a prevalência de esteatose hepática não alcoólica (NAFLD) em adolescentes obesos / Multidisciplinary treatment reduces visceral adiposity tissue, leptin, ghrelin and the prevalence of non-alcoholic fat liver disease (NAFLD) in obese adolescents

O objetivo do presente estudo foi avaliar as alterações promovidas, por intervenção multidisciplinar, nas concentrações plasmáticas de grelina e leptina, adiposidade visceral e prevalência de esteatose hepática não alcoólica (NAFLD), em adolescentes obesos. Foram avaliados 28 adolescentes obesos, 16 meninas (IMC 34,58 ± 3,86kg/m²) e 12 meninos (IMC 37,08 ± 3,17kg/m²), com idade entre 15 e 19 anos, quanto à concentração de leptina, grelina, insulina, assim como a adiposidade visceral e o diagnóstico de NAFLD pelo método de ultra-sonografia. Os resultados demonstraram redução significante na concentração circulante de grelina e leptina e na adiposidade visceral (p < 0,01). Houve ainda redução percentual na prevalência de NAFLD, sendo este um resultado relevante, visto que esta doença pode progredir para cirrose, tanto em crianças quanto em adolescentes obesos. Este tipo de tratamento demonstrou ser eficiente na melhora do perfil metabólico e hormonal, contribuindo para o controle da obesidade e suas co-morbidades em adolescentes obesos.

The aim of this study was to assess the changes promoted by a multidisciplinary therapy in ghrelin and leptin concentrations, visceral adiposity and non-alcoholic fat liver disease-NAFLD, in obese adolescents. A total of 28 obese adolescents, 16 girls (BMI 34.58 ± 3,86 wt/ht²) and 12 boys (BMI 37.08 ± 3.17 wt/ht²), aged between 15 and 19 years old, was evaluated to leptin, ghrelin and insulin concentrations, visceral adiposity and NAFLD through ultrasonography. The results showed a significant decrease in ghrelin, leptin concentrations and visceral adiposity (p < 0.01). Moreover, a decrease in the NAFLD prevalence was observed. It is an important result, since this disease can progress to cirrhosis, not only in children but also in obese adolescents. This kind of treatment can be efficient to improve metabolic and hormonal profile, as well as, to control obesity and related co-morbidities in obese adolescents.

El objetivo del presente trabajo ha sido evaluar las alteraciones promovidas por la intervención multidisciplinar, en las concentra- ciones plasmáticas de grelina y leptina, adiposidad visceral y prevalencia de esteatosis hepática no alcohólica - NAFLD, en adolescentes obesos. 28 adolescentes obesos, 16 chicas (IMC 34,58 ± 3,86 kg/m²) y 12 chicos (IMC 37,08 ± 3,17 kg/m²), con edades entre 15 y 19 años, fueron evaluados respecto a la concentración de leptina, grelina, insulina, así como a la adiposidad visceral y el diagnóstico de NAFLD por el método de ultrasonografía. Los resultados demostraron una reducción significante en la concentra- ción circulante de grelina y leptina y en la adiposidad visceral (p < 0,01). Hubo aún una reducción porcentual en la prevalencia de NAFLD, siendo este un resultado relevante, ya que esta enfermedad puede progresar hasta la cirrosis, tanto en niños como en adolescentes obesos. Este tipo de tratamiento demostró ser eficiente en la mejora del perfil metabólico y hormonal, contribuyendo para el control de la obesidad y su comorbilidad en adolescentes obesos.

Exercício físico e função cognitiva: uma revisão / Reviewing on physical exercise and the cognitive function

O exercício e o treinamento físico são conhecidos por promover diversas alterações, incluindo benefícios cardiorrespiratórios, aumento da densidade mineral óssea e diminuição do risco de doenças crônico-degenerativas. Recentemente outro aspecto tem ganhando notoriedade: trata-se da melhoria na função cognitiva. Embora haja grande controvérsia, diversos estudos têm demonstrado que o exercício físico melhora e protege a função cerebral, sugerindo que pessoas fisicamente ativas apresentam menor risco de serem acometidas por desordens mentais em relação às sedentárias. Isso mostra que a participação em programas de exercícios físicos exercem benefícios nas esferas física e psicológica e que, provavelmente, indivíduos fisicamente ativos possuem um processamento cognitivo mais rápido. Embora os benefícios cognitivos do estilo de vida fisicamente ativo pareçam estar relacionados ao nível de atividade física regular, ou seja, exercício realizado durante toda a vida, sugerindo uma "reserva cognitiva", nunca é tarde para se iniciar um programa de exercícios físicos. Dessa forma, o uso do exercício físico como alternativa para melhorar a função cognitiva parece ser um objetivo a ser alcançado, principalmente em virtude da sua aplicabilidade, pois se trata de um método relativamente barato, que pode ser direcionado a grande parte da população. Assim, o objetivo da presente revisão é o de discutir os aspectos associativos entre exercício físico e função cognitiva, permitindo uma ponderação entre o seu uso enquanto alternativa e elemento coadjuvante.

Exercise and physical training are known as promoters of several alterations, and among them, cardiorespiratory benefits, increase in the mineral bone density and decrease in the risk for chronic-degenerative diseases. Recently, another aspect has become notorious: an improvement in the cognitive function. Although it is very controversial, several studies have shown that physical exercises improve and protect the cerebral function, suggesting that physically active individuals present lower risk to develop mental disorders compared to sedentary individuals. This demonstrates that participating in physical exercise programs exerts benefits in the physical and psychological spheres, and it is probable that physically active individuals have a faster cognitive processing. Although the cognitive benefits of the physically active life-style seem to be related to the level of the regular physical activities, that is, exercises performed along the whole lifetime, suggesting a "cognitive reserve", it is never too late to start a physical exercise program. Thus, using physical exercises as an alternative to achieve an improvement in the cognitive function seems to be a aim to be attained mainly due to its applicability, since it is a relatively less expensive method that can be used by the major part of the population. Thus, the purpose of the present review is to discuss the associative aspects between physical exercises and the cognitive function, thus allowing to reflect on its use as an alternative and supportive element.

El ejercicio y la educación física así como los entrenamientos son conocidos porque promueven varios cambios en el cuerpo, incluso beneficia los efectos cardio-respiratorios, el aumento de la densidad mineral del hueso y la disminución del riesgo del enfermedades crónico-degenerativas. Más recientemente hay otro aspecto que ha obtenido fama reconocida sobre esos beneficios; se trata de la mejora en la función cognitiva. Aunque hay grandes controversias, varios estudios han estado demostrando que el ejercicio físico mejora y protege la función cerebral, mientras se hace una sugerencia que las personas se presentasen físicamente activas tendrán riesgo más pequeño sobre ataques por desórdenes mentales en relación al sedentario. Esto demonstra que la participación en programas de ejercicios tienen beneficios en las esferas física y psicológica, y que probablemente, los individuos físicamente activos tengan un procesamiento cognitivo más rápido. Aunque los beneficios cognitivos del estilo de vida fisicamente activo parecen relacionarse al nivel de actividades físicas regular, cumplido durante una vida, mientras podemos pensar que para una "reserva" cognitiva, nunca es tarde para empezar un programa de ejercicios físicos. De esta forma el uso del ejercicio físico como alternativa para mejorar la función cognitiva parece ser un objetivo a ser alcanzado, principalmente debido a la aplicabilidad del individuo por el logro personal-ademas de ser un método relativamente barato que la gran parte de la población tiene acceso. Así, el objetivo de la revisión presente es él de discutir los aspectos asociativos entre el ejercicio físico y la función cognitiva, permitiendo una consideración entre los que la usan como una alternativa y un elemento de apoyo.

Effects of paradoxical sleep deprivation and cocaine on genital reflexes in hyperlipidic-fed rats.

The present study was designed to investigate the effects of a hyperlipidic diet (HD) on penile erection (PE) and ejaculation (EJ) induced by cocaine in paradoxical sleep deprived (PSD) rats. Secondly, we aimed to verify the influence of HD cafeteria diet on steroid hormone levels. Twenty-one day-old male Wistar rats were randomly assigned into two groups: rats fed with commercial chow diet and rats fed with a palatable HD containing chow mixed with peanuts, milk chocolate and sweet cookies in the proportion of 3:2:2:1. After nine weeks of treatment, the animals were submitted to PSD or maintained as home cage control group for 96 h and challenged with cocaine (7 mg/kg, i.p.). Results showed that the HD led to a reduction in the frequency of erection in the PSD+cocaine group when compared to the PSD+cocaine fed with standard diet. Regardless of the diet, testosterone concentrations were significantly lower and progesterone was higher in the PSD rats than in the respective home-cage control rats. Although there were no hormonal alterations, the findings showed that a long-term HD might modify the stimulating effects of cocaine in potentiating genital reflexes in PSD rats.

Análise de taxa metabólica basal e composição corporal de idosos do sexo masculino antes e seis meses após exercícios de resistência / Analysis of resting metabolic rate and body composition in elderly males before and after six months of endurance exercise

O objetivo deste trabalho foi o de comparar a taxa metabólica basal e a composição corporal antes e após um programa de exercício de resistência. Foram selecionados 46 voluntários do sexo masculino com idade entre 60 e 75 (66,97 ± 4,80 anos), que foram distribuídos aleatoriamente em dois grupos: 1) grupo controle, que foi orientado a não alterar seus hábitos rotineiros e não se engajar em nenhum programa de exercício físico; e 2) grupo experimental, que participou de um programa de exercícios em cicloergômetro três vezes por semana (60 minutos) em dias alternados por seis meses, com intensidade prescrita referente à freqüência cardíaca do limiar ventilatório 1 (LV-1). Os voluntários foram submetidos a avaliação da composição corporal (DEXA); calorimetria indireta, análise sanguínea e teste ergoespirométrico. Após o período de estudo, foram observados decréscimo significativo nos hormônios tireoidianos e mudanças no metabolismo basal em ambos os grupos, mas não foram constatadas alterações na composição corporal. No entanto, o grupo experimental apresentou aumento significativo no consumo de oxigênio pico e na carga de trabalho referente à intensidade do LV-1. Os dados sugerem que um programa de exercícios aeróbios na intensidade do LV-1 não é suficiente para provocar alterações favoráveis no metabolismo basal e composição corporal de idosos, embora promova benefícios cardiovasculares.