Purpose: The purpose of this study was to determine whether time-restricted feeding (TRF) was an effective dietary strategy for reducing fat mass and preserving fat-free mass while evaluating potential changes in cardiometabolic biomarkers, hormones, muscle performance, and energy and macronutrient intake after eight weeks of aerobic exercise and resistance training in overweight and obese adults. Methods: This study was a randomized, controlled trial. Sedentary, overweight and obese adults (mean ± SD; age: 44.48 ± 7.28 years; BMI: 29.61 ± 2.62 kg/m2; females: 85.71%; males: 14.29%) were randomly assigned to a TRF or normal feeding (NF) dietary strategy group. The TRF group consumed all calories between 1200 and 2000 hours, whereas the NF group ate their typical diet. All groups completed eight weeks of aerobic exercise and supervised resistance training. Body composition, muscle performance, energy and macronutrient intake, physical activity, and physiological variables were assessed week zero and week nine. Results: A total of 21 participants completed the study (NF: n = 10; TRF: n = 11). A mild energy restriction was seen for the TRF (~300 kcal/day, 14.0%) and NF (~250 kcal/d, 11.0%) groups between baseline and week seven. Losses of total body mass were significantly greater for TRF (3.3%) relative to NF (0.2%), of which TRF had significantly greater losses of fat mass (9.0%) compared to NF (3.3%) despite similar reductions in energy intake. Lean mass increased across the intervention for both TRF (0.6%) and NF (1.9%), with no group differences. Conclusion: These data support the use of TRF and concurrent exercise training as a short-term dietary strategy for reducing fat mass and preserving lean mass in overweight and obese adults.

No description available.

Cardiovascular disease (CVD) has become one of the commonest causes of comorbidity and mortality among People living with human immunodeficiency virus (HIV) (PLWH) on antiretroviral therapy (ART). Nearly 50% of PLWH are likely to have an increased risk of developing CVD, including coronary heart disease, cerebrovascular disease, peripheral artery disease and aortic atherosclerosis. Aside from the common risk factors, HIV infection itself and side effects of antiretroviral therapy contribute to the pathophysiology of this entity. Potential non-pharmacological therapies are currently being tested worldwide for this purpose, including eating patterns such as Intermittent fasting (IF). IF is a widespread practice gaining high level of interest in the scientific community due to its potential benefits such as improvement in serum lipids and lipoproteins, blood pressure (BP), platelet-derived growth factor AB, systemic inflammation, and carotid artery intima-media thickness among others cardiovascular benefits. This review will focus on exploring the potential role of intermittent fasting as a non-pharmacological and cost-effective strategy in decreasing the burden of cardiovascular diseases among HIV patients on ART due to its intrinsic properties improving the main cardiovascular risk factors and modulating inflammatory pathways related to endothelial dysfunction, lipid peroxidation and aging. Intermittent fasting regimens need to be tested in clinical trials as an important, cost-effective, and revolutionary coadjutant of ART in the fight against the increased prevalence of cardiovascular disease in PLWH. / Revisión por pares

Inicialmente caracterizada como proteína supressora de tumor, a PTEN (phosphatase and tensin deleted on chromosome 10) tem sido objeto de estudo de trabalhos relacionados a outros processos envolvendo proliferação, sobrevivência e migração celulares, apresentando um potencial papel modulatório na neurogênese e plasticidade sináptica. Fatores ambientais, como a dieta intermitente e o exercício físico, também podem modular estes processos, podendo ser utilizados como intervenções para neuroproteção e melhora de déficits de aprendizado e memória. A ausência de PTEN em neurônios ocasiona anomalias anatômicas e funcionais, culminando em sinaptogênese aumentada e redução do LTP e LTD. Levando-se em consideração a potencial modulação da via PI3K/AKT pela dieta intermitente e pelo exercício físico, a avaliação da influência destas intervenções sobre os efeitos da deleção neuronal da PTEN constitui uma interessante ferramenta de estudo para melhor elucidação dos mecanismos associados à plasticidade sináptica. Este trabalho objetivou caracterizar bioquímica e funcionalmente o hipocampo e o córtex de camundongos adultos com deleção neuronal da PTEN, avaliando seus efeitos sob influência de intervenções não-farmacológicas. Para isto, foram utilizados camundongos com nocaute neuronal condicionado da PTEN (PtenloxP/+;Nse-Cre+). Os animais foram submetidos à dieta intermitente ou exercício físico voluntário por um período de 30 dias, avaliados por ensaios comportamentais (labirinto em cruz elevado, campo aberto, reconhecimento do objeto novo ou da localização do objeto, labirinto aquático de Morris e esquiva inibitória) e, posteriormente, foram realizadas as análises de Western Blotting, da atividade da enzima óxido nítrico sintase (NOS) e dosagem do fator neurotrófico derivado do encéfalo (BDNF). A deleção neuronal da PTEN induziu macrocefalia por aumento da massa cortical. A deleção condicionada da PTEN, sob estímulo de intervenção não-farmacológica dieta intermitente ou exercício físico induz um efeito ansiolítico nos animais, no labirinto em cruz elevado. Os resultados do campo aberto, porém, paradoxalmente não reforçam este resultado. Interessantemente, o isolamento social intrínseco ao estudo do exercício físico induziu um aumento do perfil de ansiedade nos animais, independentemente do genótipo ou tratamento. Os resultados do labirinto aquático de Morris não foram conclusivos, porém apontam para um possível déficit de memória espacial nos animais HT, além de, supreendentemente, um efeito deletério do exercício físico também observado nos níveis corticais de BDNF. Na esquiva inibitória, o déficit dos animais HT foi efetivamente resgatado pela dieta e pelo exercício físico. O hipocampo não apresentou alterações bioquímicas significativas. No córtex, pode-se confirmar a diminuição da expressão da PTEN e possível ativação da AKT, embora nenhum efeito sobre os receptores ionotrópicos glutamatérgicos tenha sido observado. O perfil de expressão da Cre recombinase foi validado por meio da linhagem Nse-Cre+;tdTomato+. O estudo da linhagem PtenloxP/+;Nse-Cre+ demonstrou um interessante potencial para avaliação dos efeitos da PTEN sobre a cognição e a plasticidade sináptica, porém um melhor balizamento dos ensaios faz-se necessário, visando a busca de condições de análise dos efeitos observados. Ainda, a expansão dos estudos com a linhagem por meio da utilização de outros estímulos pode constituir uma interessante forma de revelar os efeitos não observados. / First characterized as a tumor suppressor, PTEN (phosphatase and tensin deleted on chromosome 10) has been a target studied in many projects related to processes involving cell proliferation, survival and migration, showing a potential modulatory role in controlling neurogenesis and synaptic plasticity. Environmental factors, such as intermittent fasting and physical exercise, can also modulate those processes, thus having the potential of being applied as neuroprotective interventions aiming to improve learning and memory deficits. PTEN absence in neurons cause anatomical and functional anomalies, culminating in increased synaptogenesis and LTP and LTD reduction. Considering the potential of intermittent fasting and physical exercise to exert a modulatory role over the PI3K/AKT pathway, the assessment of the influence of these interventions over the effects of PTEN neuronal deletion is of great interest, as it can help better elucidate the mechanisms of synaptic plasticity. This work aimed to functionally and biochemically assess the hippocampus and the cortex of adult mice with a conditioned neuronal deletion of PTEN (PtenloxP/+;Nse-Cre+), evaluating its effects under the influence of non-pharmacological interventions. Animals were submitted to an intermittent fasting or to a voluntary physical exercise protocol for 30 days, then assessed by behavioral (elevated plus maze, open field, novel object or object location recognition tests, Morris water maze, and passive avoidance) and biochemical (Western blotting, nitric oxide synthase activity, BDNF levels) assays. The neuronal PTEN deletion induced macrocephaly through an increase in cortical mass. Also, under the stimuli of non-pharmacological interventions intermittent fasting or physical exercise the deletion induced an anxiolytic effect on the elevated plus maze assay. On the other hand, the open field results were paradoxical. Interestingly, social isolation an intrinsic factor from the physical exercise protocol induced an increase in the anxiety behavior, independently of genotype or treatment. Results from the Morris water maze assay were not conclusive, however they pointed to a likely spatial memory deficit on animals with the PTEN deletion. Surprisingly, a deleterious effect of physical exercise was also observed an effect found on BDNF levels as well. At the passive avoidance test, the deficit from the HT group was effectively rescued by either intermittent fasting and physical exercise. The hippocampus did not show any significant biochemical alterations. However, the decreased PTEN expression was confirmed in the cortex, as well as the possible AKT activation, although any effect over the glutamatergic ionotropic receptor was found. The Cre recombinase expression profile was validated through the reporter lineage Nse-Cre+;tdTomato+. The study of PtenloxP/+;Nse-Cre+ lineage showed great potential of assessing PTEN effects on cognition and synaptic plasticity. However, a deeper standardization of parameters is recommended in order to better evaluate the observed effects. In addition, by expanding the study of this lineage through the application of other stimuli could constitute an interesting way of revealing these non-observed results.

Made available in DSpace on 2016-12-23T13:56:00Z (GMT). No. of bitstreams: 1 Bermudes.pdf: 1280638 bytes, checksum: cf675a18fbda30bc9b61e74a1921a53e (MD5) Previous issue date: 2007-07-06 / Intermittent fasting is frequent in medical practice and this condition has been studied as a therapeutic intervention for some diseases. Increased life span and resistance to stress is observed in rodents submitted to intermittent fasting. However there is not much information on the evolution of infections in animals submitted to these diet manipulations. To study the evolution of fecal peritonitis in mice after 72 h fasting or after different time of intermittent fasting. After 72 h of fasting mice were submitted to cecal ligature and puncture or to an intraperitoneal injection of feces (1:6 or 1:9, weight/volume dilutions). Mice submitted to intermittent fasting, three days for two weeks or the day after the other day, during four months, received intraperitoneal injection of feces with the same dilutions. Mortality was evaluated up to 14 days, when the animals were killed to quantify the intraperitonel abscesses. The abscesses were classified with the values one, two or three according they were respectively up two, between two and five or higher than five millimeters in diameter. For each animal a score was obtained by the sum of values originated from the product of the number attributed to the abscesses versus the number of each abscess type. Control mice, paired by gender and age, were submitted to the same procedures. In mice submitted to 72 h fasting or intermittent fasting the signs of septic shock appeared earlier and were more severe, with higher mortality up to 24 h, although the global mortality evaluated by Kaplan-Meyer method was not significant after two weeks. Among the survivors the score of abscesses were significantly lower in mice submitted to fasting, mainly in groups treated with feces 1:9 dilution, in which occurred less mortality. Results demonstrate that acute or intermittent fasting increases the susceptibility to endotoxic shock and induces increased resistance to bacteria, demonstrated by reduction in number and volume of abscesses. / Jejum prolongado não é infrequente na prática médica e períodos intermitentes de jejum vêm sendo estudados como intervenção terapêutica para algumas doenças. Períodos intermitentes de jejum induzem aumento da longevidade e da resistência ao estresse em roedores. No entanto, pouco se conhece sobre o efeito dessas manipulações de dieta na evolução de infecções. Estudar a evolução de peritonite fecal em camundongos após jejum de 72 horas ou após períodos de jejuns intermitentes. Camundongos foram submetidos a jejum de 72 h e em seguida à ligadura e punção do ceco ou à injeção intra-peritoneal de fezes (diluídas a 1:6 ou a 1:9). Camundongos submetidos a jejum intermitente de três dias a cada duas semanas ou em dias alternados, durante quatro meses, foram submetidos a peritonite por injeção intra-peritoneal de fezes com as mesmas diluições. Foi avaliada a mortalidade até duas semanas, quando os animais foram sacrificados para contagem e mensuração dos abscessos intraperitoneais. Os abscessos recebiam os valores 1, 2 ou 3 conforme tivessem até 2, de 2 a 5 ou acima de 5 mm de diâmetro, respectivamente. Um escore para cada animal foi calculado pela soma dos valores obtidos da multiplicação do número de abscessos pelo valor atribuído ao seu tamanho. Animais controle, mantidos em dieta ad libitum , pareados por idade e sexo, foram submetidos aos mesmos procedimentos. Nos animais submetidos ao jejum agudo ou intermitente, as manifestações do choque séptico foram sempre mais precoces e mais graves, com maior mortalidade nas primeiras 48 h, embora nem sempre a diferença na sobrevivência (Kaplan-Meyer) tenha sido significativa. Nos sobreviventes, o escore dos abscessos era significativamente menor nos grupos submetidos a jejum, especialmente quando a peritonite fecal era induzida por injeção mais diluída de fezes (1:9), com menor mortalidade. Os resultados mostram que o jejum agudo ou o jejum intermitente aumentam a susceptibilidade ao choque endotóxico, mas aumenta resistência às bactérias, demonstrada pela menor extensão dos abscessos peritoneais formados.

Sammanfattning Bakgrund: Dagens stillasittande livsstil med ökat intag av energigivande ämnen resulterar i ett konstant anabolt hormonellt påslag. Detta leder till ökad övervikt och andra välfärdssjukdomar. Det rekommenderas att individer håller sig till en hög måltidsfrekvens med jämna mellanrum under dagen. Detta har börjat ifrågasättas med konkurrerande alternativ som involverar en tidigare samhällslivsstil så långt som 10 000 år sedan, då måltidsfrekvensen inte kunde planeras på samma sätt som idag. Syfte: Syftet är att under sju veckor undersöka effekten av två stycken veckovisa 24-timmars periodiska förbud mot intag av energigivande ämnen, med implementering av fysisk styrketräning och dess effekt på lean body mass (LBM) och fettvikt hos yngre individer. Metod: Två separata 24-timmars perioder av fasta i samband med tre separata styrketräningstillfällen genomfördes per vecka under sju veckor. Kroppsmått gällande kroppsfett i procent, fettvikt i kilogram (kg), kroppsdimensioner i centimeter (cm), LBM och total kroppsvikt i kg togs innan och efter studiens genomförande. Sju deltagare (två män och fem kvinnor) slutförde sitt deltagande i studien. Resultat: Samtliga deltagare ökade i LBM, med en medelökningen på 1,3 kg. Den största ökningen var 2,6 kg, och återfanns hos två deltagare. Samtliga deltagare minskade sitt procentuella kroppsfett. Den högsta minskningen var 4,8 %, den lägsta minskningen var 1 %. Medelminskningen i fettvikt var 2 kg hos individerna. Den största minskningen av fettvikt var 4,2 kg, och den lägsta minskningen var 0,64 kg. Slutsats: Periodisk fasta under två stycken 24-timmarsperioder per vecka kan fungera som ett verktyg för att minska fettprocent/fettvikt och samtidigt öka muskelmassan om det görs i kombination med tre stycken styrketräningstillfällen under samma vecka. Denna slutsats ifrågasätter äldre forskning och påståenden om vikten vid att hålla en hög och jämn måltidsfrekvens. / Abstract Background: Today's sedentary lifestyle with increased intake of energy giving substances results in a constant anabolic hormonal onset. This leads to increased obesity and other lifestyle diseases. It is recommended that individuals adhere to a high meal frequency at regular intervals throughout the day. This has been questioned with competing alternatives involving a former lifestyle as long as 10 000 years ago, when the meal frequency could not be planned in the same way as today. Objective: To investigate the effects of two 24 - hour periodic total restriction of consumption of energy giving substances, with the implementation of physical strength training and its effect on lean body mass (LBM) and fat mass in young individuals. Method: Two 24 hour periods of intermittent fasting in combination to three separate weight training sessions took place weekly for seven weeks. Body measurements involving body fat percentage, fat mass in kilograms (kg), body perimeters in centimeters (cm), LBM and total body weight in kg was measured before and after the study. Seven participants completed the study. The group included two men and five women (n = 7). Results: All participants increased their LBM, the mean increase was 1.3 kg. The largest increase was 2.6 kg, and was found among two of the participants. All participants reduced their body fat percentage. The highest reduction was 4.8 %, the lowest reduction was 1 %. The average decrease in fat weight was 2 kg. The largest reduction in fat weight was 4.2 kg, and the lowest reduction was 0.64 kg. Conclusion: Intermittent fasting during two separate 24-hour periods per week can serve as a tool in reducing body fat / fat mass while increasing muscle mass if done in combination with weight training three times during the same week. This finding questions the earlier research and claims about the importance of maintaining a consistently high meal frequency.

Type 2 diabetes mellitus (T2D) is a highly prevalent metabolic disorder linked with the development of specific complications and comorbidities that negatively affect life quality and greatly increase the risk of an early death. The main goal of T2D treatment, which in common clinical practice comprises lifestyle changes and pharmacotherapy, is to delay onset of these complications. Evidence from many recent studies shows the ability of some interventional methods to induce remission of T2D, meaning a major improvement or complete disappearance of T2D symptoms. Besides bariatric surgery procedures, some dietary regimens such as low-energy diet, low-carbohydrate diet and intermittent fasting, can also lead to T2D remission. Attributes of these dietary regimens, especially their effect in T2D treatment, is summarized in the theoretical part of this theses. The aim of the practical part of this thesis was to assess the effect of the dietary regimens mentioned above on morphometric and biochemical parameters associated with T2D by clinical and survey research. In most of the subjects with T2D, the individual dietary regimens, more precisely low-energy diet and low-carbohydrate diet, decreased body weight, where the weight loss induced by low-carbohydrate diet was caused by major decrease in the amount...

The intermittent fasting diet has a historical past, but recently, it has regained popularity as a weight loss strategy for the general public. Athletes have also picked up this specialized diet in search of a competitive edge. There are ample studies testing athletes of all levels, but most do not include females or report sex-specific results. This systematic review aimed to identify current research on the effects of intermittent fasting in the understudied population of female athletes. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a comprehensive search was conducted in three databases, including PubMed, Cochrane, and SPORTDiscus, and a total of six studies with experimental or observational designs testing the various effects of intermittent fasting on physical, physiological, and psychological parameters were included. This systematic review shows that studies found significant changes in calorie and fluid intake, body composition, nutrient utilization, well-being, and athletic performances with no changes in muscle strength, ratings of perceived exertion, blood lactate levels, and cognitive function. Multiple studies in this review found mixed results on changes in heart rate and athletic performance (vertical jump height), and no studies found negative effects on athletic performance except in the survey of athletes’ perceptions. Due to conflicting results of current research, more studies are needed to determine the effects of intermittent fasting combined with continuous exercise on athletic women.

Intermittent fasting (IF) is a recently popularized meal timing strategy whereby individuals abstain continuously from any energy intake for 16 to 20 hours each day, subsequently condensing energy intake into a short period spanning 4 to 8 hours. We aimed to test the effects of intermittent fasting in 10 individuals with Type 2 Diabetes Mellitus in conjunction with recommendations to consume a high protein diet in a 6 to 8 week withdrawal study. This study consisted of three phases: baseline, intervention, and follow-up. During the 2-week baseline and intervention phases participants consumed meals at regular times. Biochemical, anthropometric, and physical activity measurements were taken at the end of each phase. Participants reported morning, afternoon and evening self-monitored blood glucose and fasting duration on a daily basis, in addition to completing a remote food photography diary three times within each study phase. Despite the short duration of the intervention phase, intermittent fasting led to significant decreases in weight, BMI, morning SMBG, and overall reductions in waist circumference, C-reactive protein, energy intake, carbohydrate intake, and fat intake. There were significant variations between participants in response to intermittent fasting in respect to changes in lipids and insulin sensitivity, which could not be explained by baseline biochemical or anthropometric measures, fasting duration, energy intake, or physical activity. Upon cessation of intermittent fasting, biochemical changes regressed towards baseline values during the follow-up period. Intermittent fasting was well tolerated by most participants, and no severe adverse events were noted. Morning nausea was the most common complaint, which abruptly ceased when medication timing was changed.

Background: The prevalence of diabetes and obesity has been on the rise for many years and the search for new and effective dietetic solutions aiming at reducing calories, reducing body mass and improving diabetes has been ongoing. Currently, the intermittent fasting diet - the practice of alternating periods of eating and fasting - is gaining popularity. One of them is Time-restricted feeding (TRF), which time-limits energy intake within a defined window of time up to 10 hours per day without necessarily altering diet quality or quantity. A reduction in calorie intake, bodyweight, blood pressure, oxidative stress, inflammation biomarkers and triglycerides are evident with TRF studies conducted so far. Aim: The aim of the thesis is to investigate the effects of time-restricted feeding on glycemic biomarkers in human studies. Methods: A literature study is conducted with six chosen experimental studies which are primarily randomized controlled trials or randomized crossover trials with a TRF window of maximum 10 hours per day and predominantly with participants with overweight/obesity, prediabetes, type 2 diabetes and metabolic syndrome. Results: Compared to either baseline and/or control group, fasting glucose was reduced in 3 out of 6 TRF studies, while fasting insulin was reduced in 3 out of 5 TRF studies and HbA1C was decreased in 1 out of 2 TRF studies. For postprandial response, 1 out of 2 TRF studies found a reduction in glucose and likewise for insulin. Mean glucose levels were reduced in 1 out of 3 TRF studies. Insulin resistance was reduced in 3 out of 4 TRF studies while insulin sensitivity was reduced in the one study measuring this. Beta cell function improved in 2 out of 2 TRF studies compared to the control group or baseline. Conclusion: There are indications that TRF has an effect on glycemic biomarkers and thus potentially being able to reduce the risk and/or improve the treatment of type 2 diabetes. But in order to give a more definite answer more studies need to be conducted. In general, these studies should preferably have more participants and be methodologically stronger when it e.g. comes to the control of the dietary regimen.