Beneficial Short-Term Effects of Bariatric Surgery on Nutritional Inflammatory Profile and Metabolic Biomarkers.

PURPOSE: Bariatric surgery (BS) has several potential metabolic benefits. However, little is known about its impact on changes in the inflammatory potential of diet and its effect on inflammatory and metabolic markers. This study aimed to assess the short-term beneficial effects of BS on dietary inflammatory potential and inflammatory and metabolic markers. MATERIALS AND METHODS: Participants (n = 20) were evaluated 3 months before and after BS. Body mass, body mass index, anthropometric measurements, fat mass, fat-free mass, visceral fat, skeletal muscle mass, basal metabolic rate, serum lipids, HOMA-IR, QUICKI and inflammatory markers, including leptin, adiponectin, adiponectin/leptin ratio and plasminogen activator inhibitor-1 (PAI-1), were evaluated. Diet data were collected using a 3-day diet record and the dietary inflammatory index (DII®) and energy-adjusted dietary inflammatory index (E-DIITM) scores were computed. RESULTS: There was a reduction in DII® (2.56 vs 2.13) and E-DIITM (2.18 vs 0.45) indicating an improvement in inflammatory nutritional profile. Moreover, there were increases in the adiponectin/leptin ratio (0.08 vs 0.21) and QUICKI scores (0.31 vs 0.37), and reductions in leptin (36.66 vs 11.41 ng/ml) and HOMA-IR scores (3.93 vs 1.50). There were also improvements in body composition and anthropometric parameters. CONCLUSIONS: BS promotes changes in metabolic profile, inflammatory state and food intake and these modifications appeared to be associated with improvements in diet-related inflammation, an increase in the adiponectin/leptin ratio and a reduction in leptin. These results contribute to knowledge on the contribution bariatric surgery can make to the treatment of obesity and the reduction of related comorbidities.

Sleep deprivation modulates APOE and LDL receptor-related protein 1 through thyroid hormone T4 and impairs Aß clearance in hippocampus of rats.

Alzheimer's disease is the most common form of dementia. One of its pathological hallmarks is Aß accumulation, which is influenced by APOE genotype and expression, as well as by sleep homeostasis. However, conflicting mechanisms for APOE roles in Aß clearance have been reported, and the relationship between APOE and sleep also remains unclear. In this study, we aimed to investigate how hormonal alteration caused by sleep deprivation affects APOE and its receptors in rats, and to evaluate the role of different cell types in Aß clearance. Paradoxical sleep deprivation for 96 h increased Aß level in hippocampus with concomitant reduction of APOE and LRP1 at the time point within the resting period. Sleep deprivation also significantly reduced T4 levels in both active and resting times. To evaluate the effect of T4 variation, C6 glial cells and primary brain endothelial cells were treated with T4. High T4 level (300 ng/mL) increased APOE, but reduced LRP1 and LDL-R in C6 cells, while in primary endothelial cells, LDL-R levels were increased. Treatment of C6 cells with exogenous APOE reduced LRP1 and Aß uptake. These results suggest that T4 modulates LRP1 and LDL-R in both cell types, but in the opposite manner, thus, sleep deprivation might modify the ratio of the receptors in blood-brain barrier and glial cells by altering T4 levels. Considering that LRP1 and LDL-R are important for Aß clearance, sleep deprivation might also affect the degree of participation of glia in Aß clearance, and consequently, turnover of Aß in the brain.

Degenerative changes induced by paradoxical sleep deprivation in rat sublingual glands.

PURPOSE: The aim of this study was to evaluate whether sleep deprivation can induce degenerative changes in rat sublingual glands. METHODS: For this purpose, a total of 24 males were distributed into three groups: control (n = 8), in which the animals were not subjected to any procedure; sleep deprivation (n = 8) in which the animals were submitted to sleep deprivation for 96 h; recovery (n = 8), in which the animals were subjected to paradoxical sleep deprivation for 96 consecutive hours followed by 96 h without intervention. Morphological changes in sublingual glands as well as the immunoexpressions of some proteins, such as Ki-67, p16, cleaved caspase-3 and BCL-2 were investigated in this setting. RESULTS: The results showed that paradoxical sleep deprivation induced tissue degeneration as a result of the presence of pyknosis, vacuoles and areas of salivary retention, in the experimental groups. Expression of cleaved caspase 3 and BCL-2 were increased in both sleep deprivation and recovery groups. The analysis of Ki-67 showed an increase in expression only in the recovery group, associated with a decrease in p16 levels. CONCLUSION: Sleep deprivation can induce a degenerative process in the parenchyma of sublingual gland by means of dysregulation of apoptosis associated with proliferative activity.

Resistance and Aerobic Training Were Effective in Activating Different Markers of the Browning Process in Obesity.

Lifestyle changes regarding diet composition and exercise training have been widely used as a non-pharmacological clinical strategy in the treatment of obesity, a complex and difficult-to-control disease. Taking the potential of exercise in the browning process and in increasing thermogenesis into account, the aim of this paper was to evaluate the effect of resistance, aerobic, and combination training on markers of browning of white adipose tissue from rats with obesity who were switched to a balanced diet with normal calorie intake. Different types of training groups promote a reduction in the adipose tissue and delta mass compared to the sedentary high-fat diet group (HS). Interestingly, irisin in adipose tissues was higher in the resistance exercise (RE) and aerobic exercise (AE) groups compared to control groups. Moreover, in adipose tissue, the fibroblast growth factor 21 (FGF21), coactivator 1 α (PGC1α), and peroxisome proliferator-activated receptor gamma (PPARγ) were higher in response to resistance training RE compared with the control groups, respectively. Additionally, uncoupling protein 1 (UCP1) showed higher levels in response to group AE compared to the HS group. In conclusion, the browning process in white adipose tissue responds differently toward different training exercise protocols, with resistance and aerobic training efficient in activating different biomarkers of the browning process, upregulating irisin, FGF21, PGC1α, PPARγ, and UCP1 in WAT, which together may suggest an improvement in the thermogenic process in the adipose tissue. Considering the experimental conditions of the present investigation, we suggest future research to pave new avenues to be applied in clinical practices to combat obesity.

Paradoxical sleep deprivation induces tissue changes in the parotid gland of rats.

PURPOSE: This study aimed to evaluate if paradoxical sleep deprivation induces some tissue changes in the parotid gland of rats. METHODS: A total of 24 male Wistar rats were distributed into the following groups, as follows: Group 1-Control (CTRL; n = 8); Group 2-Sleep deprivation (PS; n = 8): the animals were submitted to Paradoxical Sleep deprivation for 96 h and Group 3-Recovery (R; n = 8): the animals were submitted to sleep loss for 96 h, followed by a period of 96 h without any intervention. The following parameters were evaluated: microscopic analysis, immunohistochemistry for Caspase-3, Ki-67, and COX-2 and gene expression of cytochrome C, TNF-α, and Interleukins 6, 10. RESULTS: The results pointed out acinar atrophy, and the presence of cytoplasmic vacuoles in the parenchyma of the experimental groups. In the same groups, there was differential expression of interleukins 6, 10 and TNF-α. Apoptosis was also increased by means of cleaved caspase 3 expression. The cellular proliferation (ki-67 expression) was increased the R group. CONCLUSION: Taken together, sleep deprivation induces tissue degeneration, inflammatory process, as well as activate apoptosis in the parotid gland of rats.

High and fluctuating levels of ovarian hormones induce an anxiogenic effect, which can be modulated under stress conditions: Evidence from an assisted reproductive rodent model.

Elevated levels of endogenous ovarian hormones are conditions commonly experienced by women undergoing assisted reproductive technologies (ART). Additionally, infertility-associated stress and treatment routines are factors that together may have a highly negative impact on female emotionality, which can be aggravated when several cycles of ART are needed to attempt pregnancy. This study aimed to investigate the effect of high and fluctuating levels of gonadal hormones induced by repeated ovarian stimulation on the stress response in rodents. To mimic the context of ART, female rats were exposed to an unpredictable chronic mild stress (UCMS) paradigm for four weeks. During this time, three cycles of ovarian stimulation (superovulation) (150 IU/Kg of PMSG and 75 IU/Kg of hCG) were applied, with intervals of two estrous cycles between them. The rats were distributed into four groups: Repeated Superovulation/UCMS; Repeated Superovulation/No Stress; Saline/UCMS; and Saline/No Stress. Anxiety-like and depressive-like behaviors were evaluated in a light-dark transition box and by splash test, respectively. Corticosterone, estradiol, progesterone, and biometric parameters were assessed. Data were analyzed using a two-way Generalized Linear Model (GzLM). Our results showed that repeated ovarian stimulation exerts by itself an expressive anxiogenic effect. Surprisingly, when high and fluctuating levels of ovarian hormones were combined with chronic stress, anxiety-like behavior was no longer observed, and a depressive-like state was not detected. Our findings suggest that females subjected to emotional overload induced by repeated ovarian stimulation and chronic stress seem to trigger the elaboration of adaptive coping strategies.

Inflammatory activity and apoptosis are associated with tissue degeneration in the submandibular gland of rats submitted to paradoxical sleep deprivation.

The aim of this study was to evaluate if paradoxical sleep deprivation is able to induce tissue degeneration, inflammatory activity and apoptosis in the submandibular gland of rats. A total of 24 male Wistar rats were distributed into the following groups: group 1-control (CTRL; n = 8): the animals were not submitted to any procedures; group 2-sleep deprivation (PS; n = 8): the animals were submitted to paradoxical sleep deprivation for 96 h and group 3-recovery (R; n = 8): the animals were submitted to sleep deprivation for 96 h, followed by a period of 96 h without any intervention. The following parameters were evaluated: histopathological analysis, immunohistochemistry for Ki-67, COX-2 and cleaved caspase-3 and gene expression of TNF-α, Interleukin 6 (IL-6), Interleukin 10 (IL-10) and cytochrome C by real-time PCR. The results pointed out cytoplasmic vacuoles and congested vessels in the parenchyma of submandibular gland the in PS and R groups. The expression of interleukins 6, 10 and TNF-ɑ was differentially expressed in the PS and R groups. Apoptosis was also triggered by means of increasing cleaved caspase-3 and cytochrome c expression. The cellular proliferation (Ki-67 index) was also positive in the R group. Taken together, our results demonstrate that sleep deprivation is capable of promoting tissue degeneration in the submandibular gland, as a result of inflammatory response and cellular death in rats.

Anesthesia can alter the levels of corticosterone and the phosphorylation of signaling molecules.

OBJECTIVE: Neuroscience research using laboratory animals has increased over the years for a number of reasons. Some of these studies require the use of anesthetics for surgical procedures. However, the use of anesthetics promotes several physiological changes that may interfere with experimental results. Although the anesthetics and methods of delivery used to vary, one of the most common is ketamine associated with another compound such as xylazine. We aimed to evaluate the effect of ketamine and xylazine (KX) on corticosterone levels and on the degree of phosphorylation of p44/42 (ERK1/2), Src kinases and calcium/calmodulin-dependent kinase II (CAMKII). We also compared the effects of KX on sleep deprivation, which is known to affect the hormonal profile including corticosterone. RESULTS: We found that the use of KX can increase corticosterone levels and alter the degree of phosphorylation of signaling proteins.

Effects of acute exercise on spontaneous physical activity in mice at different ages.

BACKGROUND: Exercise is often used to obtain a negative energy balance. However, its effects on body weight reduction are usually below expectations. One possible explanation is a reduction in spontaneous physical activity (SPA) after exercise since the increase in energy expenditure caused by the exercise session would be offset by the decrease in SPA and its associated energy cost. Thus, we evaluated the effects of a single bout of moderate exercise at individualized intensity on spontaneous physical activity. The impact of the single bout of exercise was determined in early adulthood and at the transition to middle age. METHODS: Male C57bl/6j (n = 10) mice were evaluated at 4 (4 M) and 9 (9 M) months of age. One week after a treadmill Maximal Exercise Capacity Test (MECT), mice performed a 30-min single bout of exercise at 50 % of the maximal speed reached at MECT. An infrared-based system was used to determine locomotor parameters (SPA and average speed of displacement, ASD) before (basal) and immediately after the single bout of exercise for 48 h (D1, 0-24 h; D2, 24-48 h). Food intake was measured simultaneously. Data were analyzed by GEE and statistical significance was set at p < 0.05. RESULTS: Basal SPA declined from 4 M to 9 M (p = 0.01), but maximal exercise capacity was similar. At both ages, SPA and ASD decreased significantly (p < 0.0001) on day 1 after exercise. On D2, SPA returned to basal levels but ASD remained lower than basal (p < 0.001). The magnitude (% of basal) of change in SPA and ASD on D1 and D2 was similar at 4 M and 9 M. Food intake did not change at 4 M but decreased on D2 at 9 M. CONCLUSIONS: A single bout of moderate exercise decreases physical activity in the first 24 h and average speed of locomotion in the 48 h following exercise. This compensation is similar from early adulthood to the transition to middle age. The decrease in both the amount and intensity (speed) of SPA may compensate for the increase in energy expenditure induced by exercise, helping to understand the below-than-expected effect of exercise interventions to cause a negative energy balance.

Histopathological changes and oxidative damage in type I and type II muscle fibers in rats undergoing paradoxical sleep deprivation.

BACKGROUND: previous studies have shown that muscle atrophy is observed after sleep deprivation (SD) protocols; however, the mechanisms responsible are not fully understood. Muscle trophism can be modulated by several factors, including energy balance (positive or negative), nutritional status, oxidative stress, the level of physical activity, and disuse. The metabolic differences that exist in different types of muscle fiber may also be the result of different adaptive responses. To better understand these mechanisms, we evaluated markers of oxidative damage and histopathological changes in different types of muscle fibers in sleep-deprived rats. METHODS: Twenty male Wistar EPM-1 rats were randomly allocated in two groups: a control group (CTL group; n = 10) and a sleep deprived group (SD group; n = 10). The SD group was submitted to continuous paradoxical SD for 96  h; the soleus (type I fibers) and plantar (type II fiber) muscles were analyzed for histopathological changes, trophism, lysosomal activity, and oxidative damage. Oxidative damage was assessed by lipid peroxidation and nuclear labeling of 8-OHdG. RESULTS: The data demonstrated that SD increased the nuclear labeling of 8-OHdG and induced histopathological changes in both muscles, being more evident in the soleus muscle. In the type I fibers there was signs of tissue degeneration, inflammatory infiltrate and tissue edema. Muscle atrophy was observed in both muscles. The concentration of malondialdehyde, and cathepsin L activity only increased in type I fibers after SD. CONCLUSION: These data indicate that the histopathological changes observed after 96 h of SD in the skeletal muscle occur by different processes, according to the type of muscle fiber, with muscles predominantly composed of type I fibers undergoing greater oxidative damage and catabolic activity, as evidenced by a larger increase in 8-OHdG labeling, lipid peroxidation, and lysosomal activity.

Insulin Modulates Myogenesis and Muscle Atrophy Resulting From Skin Scald Burn in Young Male Rats.

BACKGROUND: Burn injuries (BIs) due to scalding are one of the most common accidents among children. BIs greater than 40% of total body surface area are considered extensive and result in local and systemic response. We sought to assess morphological and myogenic mechanisms through both short- and long-term intensive insulin therapies that affect the skeletal muscle after extensive skin BI in young rats. MATERIALS AND METHODS: Wistar rats aged 21 d were distributed into four groups: control (C), control with insulin (C + I), scald burn injury (SI), and SI with insulin (SI + I). The SI groups were submitted to a 45% total body surface area burn, and the C + I and SI + I groups received insulin (5 UI/Kg/d) for 4 or 14 d. Glucose tolerance and the homeostatic model assessment of insulin resistance index were determined. Gastrocnemius muscles were analyzed for histopathological, morphometric, and immunohistochemical myogenic parameters (Pax7, MyoD, and MyoG); in addition, the expression of genes related to muscle atrophy (MuRF1 and MAFbx) and its regulation (IGF-1) were also assessed. RESULTS: Short-term treatment with insulin favored muscle regeneration by primary myogenesis and decreased muscle atrophy in animals with BIs, whereas the long-term treatment modulated myogenesis by increasing the MyoD protein. Both treatments improved histopathological parameters and secondary myogenesis by increasing the MyoG protein. CONCLUSIONS: Treatment with insulin benefits myogenic parameters during regeneration and modulates MuRF1, an important mediator of muscle atrophy.

A single ovarian stimulation, as performed in assisted reproductive technologies, can modulate the anxiety-like behavior and neuronal activation in stress-related brain areas in rats.

Infertility affects about 8 to 12% of couples of childbearing age around the world, and is recognized as a global public health issue by the WHO. From a psychosocial perspective, infertile individuals experience intense psychological distress, related to emotional disorders, which have repercussions on marital and social relationships. The symptoms persist even after seeking specialized treatment, such as assisted reproductive technologies (ART). While the stress impact of ART outcome has been comprehensively studied, the role of supraphysiological concentrations of gonadal hormones on stress response, remains to be elucidated. This study aimed to evaluate the effect of a single ovarian stimulation on the stress response in rats. To mimic the context of ART in rodents, female rats were submitted to the superovulation (150 UI/kg of PMSG and 75 UI/kg of hCG) and then to psychogenic stress (restraint stress for 30 min/day, repeated for three days). Anxiety-like behavior was evaluated in the elevated plus-maze, and neuronal activation in the stress-related brain areas assessed by Fos protein immunoreactivity. Corticosterone, estradiol, progesterone and corpora lutea were quantified. Data were analyzed using Generalized Linear Model (GzLM). Our findings indicate anxiolytic-like and protective effects of supraphysiological concentrations of gonadal hormones induced by a single ovarian stimulation on stress response. An activation of hypothalamus-pituitary-adrenal response inhibitory pathways, with participation of the prefrontal cortex, basomedial amygdala, lateral septum, medial preoptic area, dorsomedial and paraventricular hypothalamus, was detected.

Relationship among hypoxia, sleep and cognitive functions / Relación entre hipoxia, sueño y funciones cognitivas

The scientific literature shows that the reduced oxygen supply (O2) induced by acute or chronic exposure to high altitudes stimulates the organism to adapt to new physiological and psychological conditions imposed by hypoxia. Sleep can suffer partial fragmentation due to exposure to high altitudes, and these changes can be responsible for impaired cognitive functions. Therefore, this study aimed to explore the relationship between hypoxia, sleep and cognitive functions. We conducted a literature review in the period from 1978 to 2020. In that way, we concluded that hypoxia can impair sleep patterns and, consequently, cognitive functions, including memory, attention, executive functions, decision making and reaction time.

La literatura científica muestra que el suministro reducido de oxígeno (O2 ) inducido por aumentos agudos o crónicos en la altitud estimula al organismo a adaptarse a las nuevas condiciones fisiológicas y psicológicas impuestas por la hipoxia. El sueño puede sufrir fragmentación parcial debido a la exposición a grandes altitudes, y estos cambios pueden ser responsables de las funciones cognitivas deterioradas. Por lo tanto, este estudio tuvo como objetivo explorar la relación entre la hipoxia, el sueño y las funciones cognitivas. Realizamos una revisión de la literatura en el período de 1978 a 2020. Por lo tanto, se concluye que la hipoxia puede empeorar el patrón de sueño y, en consecuencia, el funcionamiento cognitivo, incluida la memoria, la atención, las funciones ejecutivas, la toma de decisiones y tiempo de reacción.

Effects of Sleep Deprivation on Acute Skeletal Muscle Recovery after Exercise.

PURPOSE: Sleep is considered essential for muscle recovery, mainly due to its effect on hormone secretion. Total sleep deprivation or restriction is known to alter not only blood hormones but also cytokines that might be related to skeletal muscle recovery. This study aimed to evaluate whether total sleep deprivation after eccentric exercise-induced muscle damage (EEIMD) modifies the profiles of blood hormones and cytokines. METHODS: In two separate conditions, with a crossover and randomized model, 10 men (age, 24.5 ± 2.9 yr; body mass index, 22.7 ± 2.3 kg·m) performed a unilateral EEIMD protocol that comprised 240 eccentric contractions of the knee extensor muscles using an isokinetic dynamometer. In one condition, a "muscle damage" protocol was followed by 48 h of total sleep deprivation and 12 h of normal sleep (DEPRIVATION). In the other condition, the same muscle damage protocol was conducted, followed by three nights of regular sleep (SLEEP). Isometric muscle voluntary contraction tests and blood samples were collected serially throughout the protocol and analyzed for creatine kinase, free and total testosterone, IGF-1, cortisol, tumor necrosis factor-alpha, interleukin (IL)-1beta, IL-6, receptor antagonist of IL-1 and IL-10. RESULTS: Muscle voluntary contraction and serum creatine kinase increased equally over the study period in both conditions. From the cytokines evaluated, only IL-6 increased in DEPRIVATION. No differences were detected in testosterone levels between conditions, but IGF-1, cortisol, and cortisol/total testosterone ratio were higher in DEPRIVATION. CONCLUSIONS: Total sleep deprivation after EEIMD does not delay muscle strength recovery but modifies inflammatory and hormonal responses.

Leucine Supplementation Improves Effort Tolerance of Rats With Hyperthyroidism.

Leucine is a regulator of protein metabolism in vivo and information on its action on effort tolerance of both animals and humans with hyperthyroidism is scarce. The objective of the present study was to verify the influence of leucine supplementation on the effort tolerance of Wistar rats with experimental hyperthyroidism. 40 animals were divided into four groups of ten: control (C), hormone (H), leucine (L), and hormone + leucine (HL). Hyperthyroidism was induced by daily administration of 20 µâ‹…g100 g-1 of levothyroxine sodium in aqueous suspension by gavage. Leucine was supplemented by adding 5% of the amino acid to the conventional feed. The animals' blood was collected by cardiac puncture to analyze TSH, T4, and T3 levels. The effort tolerance was determined by the swimming test with a 7% load attached to animals' tails. Statistical analysis was performed using the Shapiro-Wilk normality test, followed by the analysis of variance (ANOVA) of repeated measures of two factors (treatment × time) and Tukey post hoc, with a significance level of p < 0.05. Administering thyroid hormone increased the swimming performance of rats after 14 and 21 days, but with a drop in performance at 28 days. The HL group, on the other hand, had a significantly higher swimming performance compared to the other groups after 28 days of treatment. Leucine supplementation associated with the experimental model of hyperthyroidism improved the performance of rats in a swimming test after 28 days of treatment.

Maximum effort training performed in hypoxia alters the mood profile / Exercício físico máximo realizado em hipóxia altera o perfil de humor / Ejercicio físico máximo realizado en hipoxia altera el perfil del estado de ánimo

INTRODUCTION: Physical exercise at high altitude has become constant. However, the risks associated with this type of exercise represent a major concern, considering the influence of important stressors such as hypoxia and physical exercise on psychobiological and physiological responses. OBJECTIVE: Analyze the mood state and behavior of physiological variables of volunteers subjected to a progressive loading protocol until they reached maximum volitional exhaustion, both at sea level and at a simulated altitude of 4500 meters. METHOD: For both conditions studied, the volunteers responded to two instruments that assess mood responses: The Brunel Mood Scale and the Visual Analogue Mood Scale. They also underwent blood sampling to measure blood lactate levels and to evaluate oxygen-hemoglobin saturation. These procedures were performed before, immediately after, and 30 and 60 minutes after the end of the protocol. RESULTS: Hypoxia triggered negative effects on mood responses, especially when compared to sea level conditions. An increase in fatigue level (p=0.02) and mental confusion (p=0.04) was observed immediately after the exercise session, and reduction of vigor (p=0.03) was noted at 30 minutes, accompanied by a reduction in oxygen-hemoglobin saturation immediately after the session and at 30 minutes. There was also an increase in blood lactate levels immediately after the session (p=0.006). CONCLUSION: The particularities of the hypoxic environment associated with maximum exercise are able to cause a deterioration of mood and physiological responses, which can negatively modulate physical performance. This is a cross-sectional clinical study.

INTRODUÇÃO: Prática de exercícios físicos em elevadas altitudes tem se tornado constante. Entretanto, os riscos associados a esta representam uma grande preocupação, considerando a influência de importantes agentes estressores, como hipóxia e exercício físico, sobre as respostas psicobiológicas e fisiológicas. OBJETIVO: Analisar o perfil do humor e o comportamento de variáveis fisiológicas de voluntários submetidos a um protocolo de cargas progressivas até a Exaustão Voluntária Máxima no nível do mar e em altitude simulada de 4.500 metros. MÉTODOS: Para ambas as condições estudadas, os voluntários responderam a dois instrumentos que avaliam as respostas do humor, Escala de Humor de Brunel e o Visual Analogue Mood Scale, e foram submetidos à coleta de sangue para verificar a concentração de lactato sanguíneo, bem como para avaliar a saturação de oxi-hemoglobina. Esses procedimentos foram realizados antes, imediatamente depois e 30 e 60 minutos após o término do protocolo. RESULTADOS: A hipóxia desencadeou efeitos negativos sobre as respostas de humor, principalmente com relação ao nível do mar. Verificou-se aumento da fadiga (p = 0,02) e da confusão mental (p=0,04) imediatamente após a prática e redução do vigor (p = 0,03) aos 30 minutos; acompanhadas da diminuição da saturação da oxi-hemoglobina imediatamente após e aos 30 minutos; constatou-se ainda, o aumento da concentração de lactato sanguíneo no momento imediatamente após (p = 0,006). CONCLUSÃO: As particularidades do ambiente hipóxico associadas à realização do exercício físico máximo são capazes de piorar o estado de humor e as respostas fisiológicas, o que pode modular negativamente o desempenho físico. Este estudo é do tipo clínico transversal.

INTRODUCCIÓN: La práctica de ejercicios físicos en elevadas altitudes se ha vuelto constante. Entretanto, los riesgos asociados a ésta representan una gran preocupación, considerando la influencia de importantes agentes estresantes, como hipoxia y ejercicio físico, sobre las respuestas psicobiológicas y fisiológicas. OBJETIVO: Analizar el perfil del humor y el comportamiento de variables fisiológicas de los voluntarios sometidos a un protocolo de cargas progresivas hasta el Agotamiento Voluntario Máximo, al nivel del mar y a una altitud simulada de 4500 metros. MÉTODOS: Para ambas condiciones estudiadas, los voluntarios respondieron a dos instrumentos que evalúan las respuestas del humor: la Escala de Humor de Brunel y el Visual Analogue Mood Scale, y fueron sometidos a colecta de sangre para verificar la concentración de lactato sanguíneo, bien como para evaluar la saturación de oxihemoglobina. Estos procedimientos fueron realizados antes, inmediatamente después, y 30 y 60 minutos después de finalizar el protocolo. RESULTADOS: La hipoxia desencadenó efectos negativos sobre las respuestas de humor, principalmente con relación al nivel del mar. Se verificó aumento de fatiga (p = 0,02) y de la confusión mental (p = 0,04) inmediatamente después de la práctica y reducción del vigor (P = 0,03) a los 30 minutos; acompañadas de la disminución de la saturación de la oxihemoglobina inmediatamente después y a los 30 minutos; se constató además el aumento de la concentración de lactato sanguíneo en el momento inmediatamente después (p = 0,006). CONCLUSIÓN: Las particularidades del ambiente hipóxico asociadas a la realización del ejercicio físico máximo, son capaces de empeorar el estado de humor y las respuestas fisiológicas, lo que puede modular negativamente el desempeño físico. Este estudio es del tipo clínico transversal.

Melatonin and sleep responses to normobaric hypoxia and aerobic physical exercise: A randomized controlled trial.

This work evaluated the effects of moderate physical exercise performed under hypoxic conditions on melatonin and sleep. Forty healthy men were randomized into four groups: Normoxia (N) (n = 10); Hypoxia (H) (n = 10); Exercise under Normoxia (EN) (n = 10); and Exercise under Hypoxia (EH) (n = 10). The observation period for all groups was approximately 36 h, beginning with a first night devoid of any intervention. Aerobic exercise was performed by the EN and EH groups on a treadmill at 50% of the ventilatory threshold intensity for 60 min. Sleep evaluation was performed on the 1st and 2nd nights. Venous blood samples for the melatonin measurement were obtained on the 1st and 2nd days at 7:30 AM as well as on the 1st and 2nd nights at 10:30 PM. On the 2nd night, melatonin was higher in the H group than in the N group, but both were lower than values of the EH group. The nocturnal increase in melatonin was inversely correlated with the oxygen saturation of hemoglobin (SaO2%) on the 2nd night in the H group and on the 2nd day in the EH group. Diurnal remission of nocturnal melatonin appeared to be postponed in the H group and even more so in the EH group. Thus, normobaric hypoxia, which is equivalent to oxygen availability at an altitude of 4500 m, acutely increases melatonin. Moreover, diurnal remission of the nocturnal increase in melatonin seems to be delayed by hypoxia alone but even more so when acting together with exercise.

Eletromyography of abdominal muscles in different physical exercises: An update protocol for systematic review and meta-analysis.

BACKGROUND: The abdominal muscles are extremely important because they are directly involved in the functions of support, containment of viscera, and help in the process of expiration, defecation, urination, vomiting, and also at the time of childbirth. Many exercises and equipment are used to strengthen the abdominal muscles, and the workouts are proposed for a variety of purposes, such as preventing and rehabilitating low back pain, improving sports performance, achieving aesthetic standards, among others. Exercises that potentiate the electromyographic activity promote a greater recruitment of muscle fibers and are more effective to improve or maintain of the force. The electromyographic activity analysis allows us to reflect on the quality of the exercises proposed, consequently, to choose and order the exercises properly in a training session. METHODS: Our systematic review protocol will developed following the reporting items for the systematic review. To identify relevant studies, we sought articles on the following bases: MEDLINE, PubMed, Europubmed, SciELO, Physiotherapy Evidences Data Base (PEDro), Cochrane, and Google Scholar. The methodological quality of the studies included in the review will evaluated using a checklist and quality assessment. For intervention studies, risk of bias will estimated using the Cochrane Collaboration tool. RESULTS: The results of this study will show the electromyographic activation of the abdomen in the different types of exercises. CONCLUSION: Ethics approval was not required for this study because it was based on published studies. The results and findings of this study will be submitted and published in a scientific peer-reviewed journal. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42018086172.

Photobiomodulation and physical exercise on strength, balance and functionality of elderly women / Fotobiomodulação e exercício fisíco na força, equilíbrio e funcionalidade de mulheres idosas / Fotobiomodulación y ejercicio físico en la fuerza, equilibrio y funcionalidad de mujeres mayores

Abstract Introduction: Aging is associated with structural changes in muscle tissue, which leads to the loss of functional independence. The preservation of the muscle strength through strength training, and recently, low-level laser therapy (LLLT), has high clinical significance. Objective: to investigate the effects of photobiomodulation (PBM - 808 nm, 100 mW, 35.7 W/cm2 and 7 J) associated with a strength training program on quadriceps muscle strength, balance and functional capacity in elderly women. Methods: Thirty-five healthy women between 60 to 70 years old were divided into two groups: Placebo Group (n = 13) and Active Group (n = 14). The exercise protocol consisted of knee flexion-extension exercise followed by application of PBM placebo or active, twice a week for 8 consecutive weeks. Results: showed a significant increase in 6MWT (p = 0.001), SPPB (p = 0.006) and 1-MR (p = 0.001) in both groups. The strength training program associated with PBM active improved a significant increase, relative to baseline, to the right medial/lateral stability index (p = 0.007) and decrease in the Fall Risk Test (p = 0.005). Conclusion: the strength training produced a significant increase of muscle strength and functionality and when combined with the PMB it was significant in the improvement of postural stability and decrease of fall risk.

Resumo Introdução: O envelhecimento está associado a mudanças estruturais no tecido muscular, que levam à perda da independência funcional. A preservação da força muscular através do treinamento de força e, recentemente, da terapia laser de baixa intensidade (TLBI), têm alta significância clínica. Objetivo: investigar os efeitos da fotobiomodulação (808 nm, 100 mW, 35,7 W/cm2 e 7 J) associada a um programa de força muscular direcionado à força do músculo do quadríceps, equilíbrio e capacidade funcional de mulheres idosas. Métodos: 35 mulheres saudáveis entre 60 e 70 anos de idade foram divididas em dois grupos: Grupo Placebo (n = 13) e Grupo Ativo (n = 14). O protocolo de exercício consistiu no exercício de flexão e extensão de joelhos seguido da aplicação da fotobiomodulação placebo ou ativa, 2 vezes por semana por 8 semanas consecutivas. Resultados: mostraram um aumento significativo no TC6 (p = 0,001), SPPB (p = 0,006) e 1-RM (p = 0,001) em ambos os grupos. O programa de treinamento de força associado a fotobiomodulação ativa promoveu um significativo aumento relativo à avaliação inicial, no índice de estabilidade medial/lateral direito (p = 0,007) e diminuição no Teste de Risco de Queda (p = 0,005). Conclusão: o treinamento de força produziu um significativo aumento da força muscular e da funcionalidade e, quando combinado com a fotobiomodulação, foi significativo em promover estabilidade postural e diminuição do risco de queda.

Resumen Introducción: Envejecimiento está asociado a cambios estructurales en el tejido muscular, que llevan a la perdida de la independencia funcional. La preservación de la fuerza muscular a través del entrenamiento de fuerza, y recientemente, la terapia láser de baja intensidad (TLBI), tiene alta significancia clínica. Objetivo: investigar los efectos de la fotobiomodulación (808nm, 100mW, 35,7 W/cm2 y 7J) asociado a un programa de fuerza muscular del músculo cuádriceps, equilibrio y capacidad funcional de mujeres mayores. Métodos: 35 mujeres sanas entre 60 y 70 años de edad fueran repartidas en dos grupos: Grupo Ejercicio y Láser Placebo (n = 13) y Grupo Ejercicio y Láser Activo (n = 14). El protocolo de ejercicio consistió en flexión extensión de rodillas seguido de la aplicación de la fotobiomodulación placebo o activa, 2 veces en la semana durante 8 semanas consecutivas. Resultados: mostraron un aumento significativo en el TC6 (p = 0,001), SPPB (p = 0,006) y 1-RM (p = 0,001) en los dos grupos. El programa de entrenamiento de fuerza asociado a la fotobiomodulación activa promovió un aumento significativo, relativo a la evaluación inicial, en el índice de estabilidad medial / lateral derecho (p = 0,007) y disminución en la prueba de riesgo de caída (p = 0,005). Conclusión: El entrenamiento de fuerza produjo un aumento significativo de la fuerza muscular y funcionalidad, incluso cuando se combinó con la fotobiomodulación fue significativo en promover estabilidad postural y disminución del riesgo de caída.

REM sleep deprivation impairs muscle regeneration in rats.

INTRODUCTION: The aim was observe the influence of sleep deprivation (SD) and sleep recovery on muscle regeneration process in rats submitted to cryolesion. METHODS: Thirty-two Wistar rats were randomly allocated in four groups: control (CTL), SD for 96 h (SD96), control plus sleep recovery period (CTL + R) and SD96h plus 96 h of sleep recovery (SD96 + R). The animals were submitted to muscle injury by cryolesioning, after to SD and sleep recovery. RESULTS: The major outcomes of this study were the reduction of muscular IGF-1 in both legs (injured and uninjured) and a delay in muscle regeneration process of animals submitted to SD compared to animals that slept, with increase connective tissue, inflammatory infiltrate and minor muscle fibers. CONCLUSIONS: SD impairs muscle regeneration in rats, moreover reduces muscular IGF-1 and sleep recovery was able to restore it to basal levels, but it was not enough to normalize the muscle regeneration.