L'exercici físic pot compensar una dieta poc saludable?

El sobrepès i l'obesitat segueixen augmentant a causa de la dieta, sobretot en adolescents. Un estudi recent ha investigat els efectes de la dieta de cafeteria en la conducta de femelles de rata i ha demostrat que no només és metabòlicament nociva sinó que altera el comportament dels animals en dificultar les seves estratègies d'afrontament. També han observat que l'exercici aeròbic intens és capaç de compensar parcialment aquests efectes.El sobrepeso y la obesidad siguen aumentando debido a la dieta, sobre todo en adolescentes. Un estudio reciente ha investigado los efectos de la dieta de cafetería en la conducta de hembras de rata y ha demostrado que no sólo es metabólicamente nociva, sino que altera el comportamiento de los animales al dificultar sus estrategias de afrentamiento. También han observado que el ejercicio aeróbico intenso es capaz de compensar parcialmente estos efectos.Overweight and obesity continue to rise due to unhealthy diets, especially in adolescences. A recent study on the effects of a cafeteria diet with regard to coping strategies in female rats has shown, on the one hand, that this type of diet is not only metabolically harmful but alters behaviour by making coping strategies difficult, and on the other hand, that intense aerobic exercise is able partially to offset these effects

Exercici físic i dieta en models animals : efectes emocionals, fisiològics i cognitius

El sedentarisme es podria considerar una de les grans epidèmies del segle XXI. En els darrers 100 anys, els avenços tecnològics i el desenvolupament socioeconòmic han modelat la societat, eliminant gran part del treball físic i alterant els hàbits alimentaris. Les conseqüències d'aquests canvis es fan evidents en un augment de les malalties cardiovasculars, l'obesitat, la diabetis, l'estrès i l'ansietat. Aquesta tesi pretén analitzar les recomanacions sobre activitat física que fan els organismes mundials experts en salut en un model de recerca bàsica. Són adequades les recomanacions d'estil de vida saludable?El sedentarismo se podría considerar una de las grandes epidemias del siglo XXI. En los últimos 100 años, los avances tecnológicos y el desarrollo socioeconómico han modelado la sociedad, eliminando gran parte del trabajo físico y alterando los hábitos alimentarios. Las consecuencias de estos cambios se hacen evidentes en un aumento de las enfermedades cardiovasculares, la obesidad, la diabetes, el estrés y la ansiedad. Esta tesis pretende analizar las recomendaciones sobre actividad física que hacen los organismos mundiales expertos en salud en un modelo de investigación básica. ¿Son adecuadas las recomendaciones sobre un estilo de vida saludable?A sedentary lifestyle could be considered one of the great epidemics of the century. In the past 100 years, technological advances and socioeconomic development have shaped society, eliminating much of the physical work and altering eating habits. The consequences of these changes are evident in increased cardiovascular disease, obesity, diabetes, stress and anxiety. This thesis aims to analyze the physical activity recommendations made by global health organizations in a basic research model. Are recommendations for a healthy lifestyle adequate

Methods for Heart Rate Variability Biofeedback (HRVB) : A Systematic Review and Guidelines

Altres ajuts: acords transformatius de la UABHeart Rate Variability Biofeedback (HRVB) has been widely used to improve cardiovascular health and well-being. HRVB is based on breathing at an individual's resonance frequency, which stimulates respiratory sinus arrhythmia (RSA) and the baroreflex. There is, however, no methodological consensus on how to apply HRVB, while details about the protocol used are often not well reported. Thus, the objectives of this systematic review are to describe the different HRVB protocols and detect methodological concerns. PsycINFO, CINALH, Medline and Web of Science were searched between 2000 and April 2021. Data extraction and quality assessment were based on PRISMA guidelines. A total of 143 studies were finally included from any scientific field and any type of sample. Three protocols for HRVB were found: (i) "Optimal RF" (n = 37), each participant breathes at their previously detected RF; (ii) "Individual RF" (n = 48), each participant follows a biofeedback device that shows the optimal breathing rate based on cardiovascular data in real time, and (iii) "Preset-pace RF" (n = 51), all participants breathe at the same rate rate, usually 6 breaths/minute. In addition, we found several methodological differences for applying HRVB in terms of number of weeks, duration of breathing or combination of laboratory and home sessions. Remarkably, almost 2/3 of the studies did not report enough information to replicate the HRVB protocol in terms of breathing duration, inhalation/exhalation ratio, breathing control or body position. Methodological guidelines and a checklist are proposed to enhance the methodological quality of future HRVB studies and increase the information reported

Treadmill intervention attenuates the cafeteria diet-induced impairment of stress-coping strategies in young adult female rats

The current prevalence of diet-induced overweight and obesity in adolescents and adults is continuously growing. Although the detrimental biochemical and metabolic consequences of obesity are widely studied, its impact on stress-coping behavior and its interaction with specific exercise doses (in terms of intensity, duration and frequency) need further investigation. To this aim, we fed adolescent rats either an obesogenic diet (cafeteria diet, CAF) or standard chow (ST). Each group was subdivided into four subgroups according to the type of treadmill intervention as follows: a sedentary group receiving no manipulation; a control group exposed to a stationary treadmill; a low-intensity treadmill group trained at 12 m/min; and a higher intensity treadmill group trained at 17 m/min. Both the diet and treadmill interventions started at weaning and lasted for 8 weeks. Subjects were tested for anxiety-like behavior in the open field test and for coping strategies in the two-way active avoidance paradigm at week 7 and were sacrificed at week 8 for biometric and metabolic characterization. CAF feeding increased the weight gain, relative retroperitoneal white adipose tissue (RWAT %), and plasma levels of glucose, insulin, triglycerides and leptin and decreased the insulin sensitivity. Treadmill intervention partially reversed the RWAT% and triglyceride alterations; at higher intensity, it decreased the leptin levels of CAF-fed animals. CAF feeding decreased the motor activity and impaired the performance in a two-way active avoidance assessment. Treadmill intervention reduced defecation in the shuttle box, suggesting diminished anxiety. CAF feeding combined with treadmill training at 17 m/min increased the time spent in the center of the open field and more importantly, partially reversed the two-way active avoidance deficit. In conclusion, this study demonstrates that at doses that decreased anxiety-like behavior, treadmill exercise partially improved the coping strategy in terms of active avoidance behavior in the CAF-fed animals. This effect was not observed at lower doses of treadmill training

Long-term exercise modulates hippocampal gene expression in sencescent females mice

Altres ajuts: FI-DGR 2011 de la Generalitat de CatalunyaThe senescence-accelerated SAMP8 mouse is considered a useful non-transgenic model for studying aspects of progressive cognitive decline and Alzheimer's disease (AD). Using SAMR1 mice as controls, here we explored the effects of 6 months of voluntary wheel running in 10-month-old female SAMP8 mice. Exercise in SAMP8 mice improved phenotypic features associated with premature aging (i.e., skin color and body tremor) and enhanced vascularization and BDNF gene expression in the hippocampus compared with controls. With the aim of identifying genes involved in brain aging responsive to long-term exercise, we performed whole genome microarray studies in hippocampus from sedentary SAMP8 (P8sed), SAMR1 (R1sed), and exercised SAMP8 (P8run) mice. The genes differentially expressed in P8sed versus R1sed were considered as putative aging markers (i) and those differentially expressed in P8run versus P8sed were considered as genes modulated by exercise (ii). Genes differentially expressed in both comparisons (i and ii) were considered as putative aging genes responsive to physical exercise. We identified 34 genes which met both criteria. Gene ontology analysis revealed that they are mainly involved in functions related to extracellular matrix maintenance. Selected genes were validated by real-time quantitative PCR assays, i.e., collagen type 1 alpha 1 (col1a1), collagen type 1 alpha 2 (col1a2), fibromodulin (fmod), prostaglandin D(2) synthase (ptgds), and aldehyde dehydrogenase (Aldh1a2). As a whole, our study suggests that exercise training during adulthood may prevent or delay gene expression alterations and processes associated with hippocampal aging in at-risk subjects

Epigenetic alterations in hippocampus of SAMP8 senescent mice and modulation by voluntary physical exercise

The senescence-accelerated SAMP8 mouse model displays features of cognitive decline and Alzheimer's disease. With the purpose of identifying potential epigenetic markers involved in aging and neurodegeneration, here we analyzed the expression of 84 mature miRNAs, the expression of histone-acetylation regulatory genes and the global histone acetylation in the hippocampus of 8-month-old SAMP8 mice, using SAMR1 mice as control. We also examined the modulation of these parameters by 8 weeks of voluntary exercise. Twenty-one miRNAs were differentially expressed between sedentary SAMP8 and SAMR1 mice and seven miRNAs were responsive to exercise in both strains. SAMP8 mice showed alterations in genes involved in protein acetylation homeostasis such as Sirt1 and Hdac6 and modulation of Hdac3 and Hdac5 gene exprssion by exercise. Global histone H3 acetylation levels were reduced in SAMP8 compared with SAMR1 mice and reached control levels in response to exercise. In sum, data presented here provide new candidate epigenetic markers for aging and neurodegeneration and suggest that exercise training may prevent or delay some epigenetic alterations associated with accelerated aging

Macroautophagic process was differentially modulated by long-term moderate exercise in rat brain and peripheral tissues

The autophagic process is a lysosomal degradation pathway, which is activated during stress conditions, such as starvation or exercise. Regular exercise has beneficial effects on human health, including neuroprotection. However, the cellular mechanisms underlying these effects are incompletely understood. Endurance and a single bout of exercise induce autophagy not only in brain but also in peripheral tissues. However, little is known whether autophagy could be modulated in brain and peripheral tissues by long-term moderate exercise. Here, we examined the effects on macroautophagy process of long-term moderate treadmill training (36 weeks) in adult rats both in brain (hippocampus and cerebral cortex) and peripheral tissues (skeletal muscle, liver and heart). We assessed mTOR activation and the autophagic proteins Beclin 1, p62, LC3B (LC3B-II/LC3B-I ratio) and the lysosomal protein LAMP1, as well as the ubiquitinated proteins. Our results showed in the cortex of exercised rats an inactivation of mTOR, greater autophagy flux (increased LC3-II/LC3-I ratio and reduced p62) besides increased LAMP1. Related with these effects a reduction in the ubiquitinated proteins was observed. No significant changes in the autophagic pathway were found either in hippocampus or in skeletal and cardiac muscle by exercise. Only in the liver of exercised rats mTOR phosphorylation and p62 levels increased, which could be related with beneficial metabolic effects in this organ induced by exercise. Thus, our findings suggest that long-term moderate exercise induces autophagy specifically in the corte

Epigenetic alterations in hippocampus of SAMP8 senescent mice and modulation by voluntary physical exercise

The senescence-accelerated SAMP8 mouse model displays features of cognitive decline and Alzheimer's disease. With the purpose of identifying potential epigenetic markers involved in aging and neurodegeneration, here we analyzed the expression of 84 mature miRNAs, the expression of histone-acetylation regulatory genes and the global histone acetylation in the hippocampus of 8-month-old SAMP8 mice, using SAMR1 mice as control. We also examined the modulation of these parameters by 8 weeks of voluntary exercise. Twenty-one miRNAs were differentially expressed between sedentary SAMP8 and SAMR1 mice and seven miRNAs were responsive to exercise in both strains. SAMP8 mice showed alterations in genes involved in protein acetylation homeostasis such as Sirt1 and Hdac6 and modulation of Hdac3 and Hdac5 gene expression by exercise. Global histone H3 acetylation levels were reduced in SAMP8 compared with SAMR1 mice and reached control levels in response to exercise. In sum, data presented here provide new candidate epigenetic markers for aging and neurodegeneration and suggest that exercise training may prevent or delay some epigenetic alterations associated with accelerated aging

Long-term moderate treadmill exercise promotes stress-coping strategies in Male and female rats

This study has been supported by Spanish grants from Ministerio de Economía y Competitividad to LC (PSI2011-29807-C02-01) and AA (SAF2011-28313); and from Instituto de Salud Carlos III (RD12/0028/0014, Redes Temáticas de Investigación Cooperativa en Salud, Ministerio de Sanidad y Consumo), and Generalitat de Catalunya (SGR2014-1020) to AA. JFL was supported by a pre-doctoral fellowship from the Generalitat de Catalunya (FI-DGR 2011). IC was supported by a pre-doctoral fellowship from Universidad Santo Tomás, Chile and a fellowship from CONYCYT/BECA CHILE/PAI 72150035. SF was a recipient of a PTA-MICINN fellowship (PTA 2010-3472-I). We would like to thank Juan Ramón Garcia Milla, Rafaela Gascón Palomar, Carlos Baldellou Estrada, Maria del Mar López González and all Servei d'Estabulari staff (UAB) for their help with animal care.Recent evidence has revealed the impact of exercise in alleviating anxiety and mood disorders; however, the exercise protocol that exerts such benefit is far from known. The current study was aimed to assess the effects of long-term moderate exercise on behavioural coping strategies (active vs. passive) and Hypothalamic-Pituitary-Adrenal response in rats. Sprague-Dawley male and female rats were exposed to 32-weeks of treadmill exercise and then tested for two-way active avoidance learning (shuttle-box). Two groups were used as controls: a non-handled sedentary group, receiving no manipulation, and a control group exposed to a stationary treadmill. Female rats displayed shorter escape responses and higher number of avoidance responses, reaching criterion for performance earlier than male rats. In both sexes, exercise shortened escape latencies, increased the total number of avoidances and diminished the number of trials needed to reach criterion for performance. Those effects were greater during acquisition in female rats, but remained over the shuttle-box sessions in treadmill trained male rats. In females, exercise did not change ACTH and corticosterone levels after shuttle-box acquisition. Collectively, treadmill exercise improved active coping strategies in a sex-dependent manner. In a broader context, moderate exercise could serve as a therapeutic intervention for anxiety and mood disorders

The Cafeteria Diet: a standardized protocol and its effects on behavior

Obesity is a major health risk, with junk food consumption playing a central role in weight gain, because of its high palatability and high-energy nutrients. The Cafeteria (CAF) diet model for animal experiments consists of the same tasty but unhealthy food products that people eat (e.g. hot dogs and muffins), and considers variety, novelty and secondary food features, such as smell and texture. This model, therefore, mimics human eating patterns better than other models. In this paper, we systematically review studies that have used a CAF diet in behavioral experiments and propose a standardized CAF diet protocol. The proposed diet is ad libitum and voluntary; combines different textures, nutrients and tastes, including salty and sweet products; and it is rotated and varied. Our summary of the behavioral effects of CAF diet show that it alters meal patterns, reduces the hedonic value of other rewards, and tends to reduce stress and spatial memory. So far, no clear effects of CAF diet were found on locomotor activity, impulsivity, coping and social behavior