Obesity is considered to be a worldwide epidemic disease characterized by an accumulation of AT. Increased adiposity can perturb normal metabolic functions and lead to the development of diseases like insulin resistance and other metabolic disorders. A large amount of clinical studies have been shown that changes in inflammatory signaling in adipose tissue cells, increased infiltration of immune cells into AT as well as stress of endoplasmic reticulum belong to the key molecular steps leading to the development of metabolic disturbances associated with this disease. Adverse metabolic effects of AT accumulation can be diminished by calorie restriction resulting in weight loss. In addition, stress of endoplasmic reticulum could be alleviated by chemical chaperones including bile acids. These two approaches for the treatment of obesity or the obesity-associated disturbances were basis for this PhD thesis. In the first part of this work, we studied inflammation status of gluteal in comparison with abdominal AT and differentiation and secretory capacity of adipocytes after weight loss in obese patients. We revealed that inflammatory profile of gluteal AT, estimated by mRNA level of macrophages and cytokines as markers of inflammatory status of the body, did not explain the different clinical impact of...

Cancer is a leading cause of death in the United States and the world. Based on the literature, the side effects of prolonged use of cancer treatment pose a threat to the patient's treatment compliance and efficacy. This study aims to determine the extent to which calorie restriction and fasting can improve the efficacy of cancer treatments, tolerability of cancer treatments, and compliance with cancer treatments through a systematic review. The search for studies involved the use of key terms and extenders based on population, intervention, comparator, outcomes, and study designs (PICOS) framework including participants receiving cancer treatment, dietary interventions, and cancer treatment outcomes. All search results were uploaded to Covidence® software and two independent blinded reviewers screened the studies, and three independent reviewers extracted the data. Studies were first screened based on the title and abstract, and then they were screened based on the full text. If the synthesized data had similar characteristics and there were enough studies available, then the meta-analysis would be performed. While Riedinger et al., Voss et al., and de Groot et al. did not find any significant difference in treatment efficacy between fasting and control groups, the earlier study done by de Groot et al. showed that the effects of fasting can show significant improvement in decreasing the amount of DNA damage in noncancerous cells. Regarding the effects of fasting and calorie restriction on patient tolerability when receiving chemotherapy or radiotherapy, all studies covering the effect demonstrate a trend suggesting that there is no significant difference between the dietary intervention groups and control groups. Overall, there is not enough information from these studies to conclude the effect of fasting on treatment compliance.

Master of Science / Department of Human Nutrition / Weiqun Wang / Weight control through either dietary calorie restriction (DCR) or exercise is associated with cancer prevention in animal models. However, the underlying mechanisms are not fully defined. Bioinformatics approaches using genomics, proteomics, and lipidomics were employed to elucidate the profiling changes of genes, proteins, and phospholipids in response to weight loss by DCR or exercise in a mouse skin cancer model. SENCAR mice were randomly assigned into 4 groups for 10 weeks: ad lib-fed sedentary control, ad lib-fed exercise (AE), exercise but pair-fed isocaloric amount of control (PE), and 20% DCR. Two hours after topical TPA treatment, skin epidermis was analyzed by Affymetrix for gene expression, DIGE for proteomics, and lipidomics for phospholipids. Body weights were significantly reduced in both DCR and PE but not AE mice versus the control. Among 39,000 transcripts, 411, 67, and 110 genes were significantly changed in DCR, PE, and AE, respectively. The expression of genes relevant to PI3K-Akt and Ras-MAPK signaling was effectively reduced by DCR and PE as measured through GenMAPP software. Proteomics analysis identified ~120 proteins, with 22 proteins significantly changed by DCR, including upregulated apolipoprotein A-1, a key antioxidant protein that decreases Ras-MAPK activity. Of the total 338 phospholipids analyzed by lipidomics, 57 decreased by PE including 5 phophatidylinositol species that serve as PI3K substrates. Although there were many impacts that we still need to characterize, it appears that both Ras-MAPK and PI3K-Akt signaling pathways are the key cancer preventive targets that have been consistently demonstrated by three bioinformatics approaches.

Doctor of Philosophy / Department of Human Nutrition / Weiqun Wang / Weight control via dietary caloric restriction and/or exercise has been demonstrated for cancer prevention. However, the underlying mechanisms are not clear. Previous studies in our lab showed that IGF-1 and IGF-1-dependent signaling were reduced by weight control. To confirm the requirement of IGF-1 reduction for cancer prevention, we restored IGF-1 in the exercised mice, which partially reversed the reduction of TPA-induced PI3K expression and PI3K-related 38:4 PI substrate. To explore the overall mechanistic impact, we further studied the effect of weight control on the profiles of lipid, gene and protein expression in TPA treated skin tissues. The mice were randomly assigned into 4 groups: ad libitum-fed sedentary control (control), ad libitum-fed exercise (AL+Exe), exercise but pair-fed at the amount of control (PF+Exe), and 20% of dietary calorie restriction (DCR). At the end of 10 weeks, the mice were treated with TPA topically for two hours. The body weights were significantly reduced in DCR and PF+Exe but not AL+Exe mice when compared with the control. Plasma and skin tissue triacylglycerides were significantly decreased in PF+Exe and DCR groups but not AL+Exe. Similar impact was found for the diacylglyceride profile in both plasma and skin tissue accordingly. Using Affymetrix microarray, 784, 223, and 152 probe sets were respectively found significantly changed by DCR, PF+Exe, and AL+Exe. PF+Exe and DCR showed similar impact on signaling pathways-related gene expression as analyzed by GenMAPP. Of the total 86 proteins identified by 2D-DIGE proteomics, 20 proteins were significantly changed by DCR. Overall, our results showed weight control via DCR or pair-fed exercise rather than exercise with ad libitum feeding significantly reduced body weight and body fat, resulting in reduction of IGF-1 and IGF-1-induced signaling such as PI3K and PI-related pathway. The overall impact upon lipid profiling and gene and protein expression by weight loss suggests many other mechanistic targets. Although we could not ambitiously clarify all the changes were related to anticancer mechanisms in the scope of this study, understanding of the relationship between weight control and TPA-induced skin cancer risk as well as IGF-1-dependent signaling pathways may reveal intrinsic mechanisms and provide novel approaches to prevent cancer in the future studies.

Thesis advisor: Thomas N. Seyfried / Epilepsy is a prevalent disabling chronic and socially isolating neurological disorder that involves recurrent abnormal discharges of neurons. Despite seizures afflicting about 10% of people worldwide, antiepileptic drugs (AEDs) are largely unable to manage seizures in many persons with epilepsy. As an alternative to AEDs, dietary therapies possess a broad therapeutic potential in both humans and animals models of various neurological and neurodegenerative disease etiologies. My research focus was to identify the therapeutic efficacy and potential mechanism(s) of action of calorie restriction (CR) and the ketogenic diet (KD) in both the epileptic EL mouse model and the Mecp2<super>308/y<super/> mouse model of Rett syndrome. My findings indicate that both the KD and CR can reduce seizure susceptibility in EL mice, a natural model for multifactorial idiopathic generalized epilepsy. CR and circulating glucose and ketone levels significantly influence the therapeutic efficacy of the KD. A concurrent reduction in circulating plasma glucose levels and elevation in circulating plasma &beta-hydroxybutyrate levels was predicted to associate with the anticonvulsant effect of these diets in EL mice. For the first time, I was able to show that a KD fed in unrestricted amount is able to reduce seizure threshold in EL mice. Interestingly, supplementation of calories in the form of carbohydrate in the water of calorie-restricted EL mice results in a diminished anticonvulsant efficacy of the KD. In my effort to elucidate the neuroprotective mechanism(s) associated with these changes in metabolite availability, I started investigating the complex alterations occurring in multiple integrated neural and metabolic processes. Furthermore, I showed that a restricted KD diet improves aspects of the behavioral abnormalities seen in Rett mice, in particular with respect to anxiety. Finally, for the first time, I provide a standardized protocol for the implementation of diet therapies in the management of an array of neurological and neurodegenerative diseases, which ultimately may help elucidate the complex neuroprotective mechanism(s) of CR and the KD. This research overall has provided a new understanding in the therapeutic efficacy of diets in epilepsy and Rett Syndrome. / Thesis (PhD) — Boston College, 2010. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Biology.

O envelhecimento envolve um progressivo declínio na eficiência metabólica dos sistemas biológicos ao longo do tempo. Embora não possa ser evitado, o envelhecimento pode ter seus fenótipos típicos mitigados em organismos submetidos à restrição calórica, um regime dietético que consiste em uma oferta diminuída de calorias. Ao longo do tempo, a levedura Saccharomyces cerevisiae mostrou-se um importante organismo modelo para o estudo de importantes marcas relacionadas ao envelhecimento, sobretudo por ser responsiva à restrição calórica. Através de uma abordagem do metabolismo energético e do estado de óxido-redução celular, nós temos buscado identificar quais são os fatores imprescindíveis para a exibição do aumento do tempo de vida cronológico dessa levedura. Nós verificamos que defeitos específicos na síntese de nicotinamida adenina dinucleotídeo aumentam a geração mitocondrial de espécies reativas de oxigênio pela enzima dihidrolipoil desidrogenase, porém não suprimem o aumento da do tempo de vida cronológico de S. cerevisiae. Por outro lado, os mutantes dessa levedura irreponsíveis à restrição calórica são aqueles que possuem defeitos no metabolismo aeróbico, mais especificamente na montagem da cadeia de transporte de elétrons. Também verificamos que diferentes mutações em enzimas do ciclo dos ácidos tricarboxílicos alteram a taxa de perda do DNA mitocondrial de S. cerevisiae numa forma dependente da concentração inicial de glicose nos meios de cultura e também do tempo de cultivo. Também observamos que a eficiência energética em S. cerevisiae cultivada sob restrição calórica é aumentada em relação à levedura cultivada em condição controle. Finalmente, também observamos que a morfologia mitocondrial é alterada pelo estado metabólico celular e se correlaciona com a geração de espécies reativas de oxigênio nesse organismo. Assim sendo, em conjunto, esses dados revelam importantes modificações metabólicas e no estado de óxido redução proporcionadas pela restrição calórica e como os fenótipos típicos do envelhecimento podem ser mitigados em S. cerevisiae, assim como quais são os fatores imprescindíveis para a resposta dessa levedura à restrição calórica. / Aging involves a progressive decline in metabolic efficiency of biological systems over time. Although it cannot be avoided, aging phenotypes are delayed in organisms undergoing caloric restriction, a dietary regimen consisting of a reduced availability of calories. The yeast Saccharomyces cerevisiae has proved to be an important model organism for studying important characteristics related to aging, and is responsive to caloric restriction. We sought to identify factors essential for increased chronological lifespan in yeast by investigating changes in energy metabolism and redox state. We found that defects in the synthesis of nicotinamide adenine dinucleotide increased mitochondrial generation of reactive oxygen species by the enzyme dihidrolipoil dehydrogenase, but did not suppress the increase in chronological life span. On the other hand, mutants of this yeast which do not respond to caloric restriction are those that have defects in aerobic metabolism, specifically in the assembly of the electron transport chain. We also found that different mutations in enzymes of the citric acid cycle alter the rate of loss of mitochondrial in a manner dependent on the initial concentration of glucose in culture media and culture time. We also observed that energy efficiency in S. cerevisiae grown under caloric restriction is increased compared to yeast grown under control conditions. Finally, we also observed that mitochondrial morphology is altered by the cellular metabolic state and correlates with the generation of reactive oxygen species in this organism. Thus, altogether, these data reveal significant changes in metabolism and redox state promoted by caloric restriction, how phenotypes typical of aging can be prevented in S. cerevisiae, as well as what factors are required for the response of yeast to caloric restriction.

Neste estudo, avaliamos o efeito da restrição calórica e do treinamento resistido na massa corporal e na sensibilidade à insulina de ratas ovariectomizadas. 80 ratas fêmeas da linhagem Holtzman foram distribuídas em 8 grupos (n=10 cada): ovariectomizado (OVX), ovariectomizado com restrição calórica (OVX RC), ovariectomizado com treinamento resistido (OVX TR), ovariectomizado com restrição calórica e treinamento resistido (OVX TR+RC), Sham operado (SHAM), Sham com restrição calórica (SHAM RC), sham com treinamento resistido (SHAM TR), sham com restrição calórica e treinamento resistido (SHAM TR+RC). Após 13 semanas de intervenção, foram analisados: massa corporal, gordura corporal; concentrações sanguíneas de glicose, insulina e adiponectina; conteúdo de AKT total e fosforilada, pi3k e Glut 4 (nos tecidos adiposos subcutâneo e retroperitoneal). As ratas ovariectomizadas (OVX, OVX RC, OVX TR e OVX TR+RC) apresentaram maior massa corporal e gordura corporal quando comparadas ao grupo SHAM. As concentrações de glicose e insulina foram semelhantes em todos os grupos experimentais, porém a concentração de adiponectina foi menor nos grupos ovariectomizados (OVX, OVX RC, OVX TR e OVX TR+RC), quando comparados ao grupo SHAM. A RC e o TR aumentaram a concentração de adiponectina quando comparado ao grupo OVX. Não houve diferença entre os grupos em relação à via de sinalização da insulina nos tecidos adiposos subcutâneo e retroperitoneal. Concluímos que a ovariectomia causa aumento de massa e gordura corporal, levando à menor concentração de adiponectina, e que a RC e o TR alteram estas modificações. / In this study, we evaluated the effect of calorie restriction and strength training on the body weight and insulin sensitivity of ovariectomized rats. Eighty female Holtzman rats were divided into eight groups (n=10 per group): ovariectomized (OVX), ovariectomized plus calorie restriction (OVX-CR), ovariectomized plus strength training (OVX-ST), ovariectomized plus strength training and calorie restriction (OVX-ST+CR), sham operated (SHAM), sham plus calorie restriction (SHAM-CR), sham plus strength training (SHAM-ST), and sham plus strength training and calorie restriction (SHAM-ST+CR). The following variables were analyzed after 13 weeks of intervention: body weight; body fat; blood concentrations of glucose, insulin and adiponectin; total and phosphorylated AKT content; pi3k and Glut 4 (in subcutaneous and retroperitoneal adipose tissues). Ovariectomized rats (OVX, OVX-CR, OVX-ST, and OVX-ST+CR) had a higher body weight and body fat than SHAM animals. Glucose and insulin concentrations were similar in all experimental groups, but adiponectin concentration was lower in the ovariectomized groups (OVX, OVX-CR, OVX-ST, and OVX-ST+CR) when compared to the SHAM group. Calorie restriction and ST increased the concentration of adiponectin when compared to the OVX group. There was no difference between groups in terms of insulin signaling in subcutaneous or retroperitoneal adipose tissue. We conclude that ovariectomy increases body weight and body fat, reducing adiponectin concentration, and that CR and ST alter these modifications.

O envelhecimento envolve um progressivo declínio na eficiência metabólica dos sistemas biológicos ao longo do tempo. Embora não possa ser evitado, o envelhecimento pode ter seus fenótipos típicos mitigados em organismos submetidos à restrição calórica, um regime dietético que consiste em uma oferta diminuída de calorias. Ao longo do tempo, a levedura Saccharomyces cerevisiae mostrou-se um importante organismo modelo para o estudo de importantes marcas relacionadas ao envelhecimento, sobretudo por ser responsiva à restrição calórica. Através de uma abordagem do metabolismo energético e do estado de óxido-redução celular, nós temos buscado identificar quais são os fatores imprescindíveis para a exibição do aumento do tempo de vida cronológico dessa levedura. Nós verificamos que defeitos específicos na síntese de nicotinamida adenina dinucleotídeo aumentam a geração mitocondrial de espécies reativas de oxigênio pela enzima dihidrolipoil desidrogenase, porém não suprimem o aumento da do tempo de vida cronológico de S. cerevisiae. Por outro lado, os mutantes dessa levedura irreponsíveis à restrição calórica são aqueles que possuem defeitos no metabolismo aeróbico, mais especificamente na montagem da cadeia de transporte de elétrons. Também verificamos que diferentes mutações em enzimas do ciclo dos ácidos tricarboxílicos alteram a taxa de perda do DNA mitocondrial de S. cerevisiae numa forma dependente da concentração inicial de glicose nos meios de cultura e também do tempo de cultivo. Também observamos que a eficiência energética em S. cerevisiae cultivada sob restrição calórica é aumentada em relação à levedura cultivada em condição controle. Finalmente, também observamos que a morfologia mitocondrial é alterada pelo estado metabólico celular e se correlaciona com a geração de espécies reativas de oxigênio nesse organismo. Assim sendo, em conjunto, esses dados revelam importantes modificações metabólicas e no estado de óxido redução proporcionadas pela restrição calórica e como os fenótipos típicos do envelhecimento podem ser mitigados em S. cerevisiae, assim como quais são os fatores imprescindíveis para a resposta dessa levedura à restrição calórica. / Aging involves a progressive decline in metabolic efficiency of biological systems over time. Although it cannot be avoided, aging phenotypes are delayed in organisms undergoing caloric restriction, a dietary regimen consisting of a reduced availability of calories. The yeast Saccharomyces cerevisiae has proved to be an important model organism for studying important characteristics related to aging, and is responsive to caloric restriction. We sought to identify factors essential for increased chronological lifespan in yeast by investigating changes in energy metabolism and redox state. We found that defects in the synthesis of nicotinamide adenine dinucleotide increased mitochondrial generation of reactive oxygen species by the enzyme dihidrolipoil dehydrogenase, but did not suppress the increase in chronological life span. On the other hand, mutants of this yeast which do not respond to caloric restriction are those that have defects in aerobic metabolism, specifically in the assembly of the electron transport chain. We also found that different mutations in enzymes of the citric acid cycle alter the rate of loss of mitochondrial in a manner dependent on the initial concentration of glucose in culture media and culture time. We also observed that energy efficiency in S. cerevisiae grown under caloric restriction is increased compared to yeast grown under control conditions. Finally, we also observed that mitochondrial morphology is altered by the cellular metabolic state and correlates with the generation of reactive oxygen species in this organism. Thus, altogether, these data reveal significant changes in metabolism and redox state promoted by caloric restriction, how phenotypes typical of aging can be prevented in S. cerevisiae, as well as what factors are required for the response of yeast to caloric restriction.

Neste estudo, avaliamos o efeito da restrição calórica e do treinamento resistido na massa corporal e na sensibilidade à insulina de ratas ovariectomizadas. 80 ratas fêmeas da linhagem Holtzman foram distribuídas em 8 grupos (n=10 cada): ovariectomizado (OVX), ovariectomizado com restrição calórica (OVX RC), ovariectomizado com treinamento resistido (OVX TR), ovariectomizado com restrição calórica e treinamento resistido (OVX TR+RC), Sham operado (SHAM), Sham com restrição calórica (SHAM RC), sham com treinamento resistido (SHAM TR), sham com restrição calórica e treinamento resistido (SHAM TR+RC). Após 13 semanas de intervenção, foram analisados: massa corporal, gordura corporal; concentrações sanguíneas de glicose, insulina e adiponectina; conteúdo de AKT total e fosforilada, pi3k e Glut 4 (nos tecidos adiposos subcutâneo e retroperitoneal). As ratas ovariectomizadas (OVX, OVX RC, OVX TR e OVX TR+RC) apresentaram maior massa corporal e gordura corporal quando comparadas ao grupo SHAM. As concentrações de glicose e insulina foram semelhantes em todos os grupos experimentais, porém a concentração de adiponectina foi menor nos grupos ovariectomizados (OVX, OVX RC, OVX TR e OVX TR+RC), quando comparados ao grupo SHAM. A RC e o TR aumentaram a concentração de adiponectina quando comparado ao grupo OVX. Não houve diferença entre os grupos em relação à via de sinalização da insulina nos tecidos adiposos subcutâneo e retroperitoneal. Concluímos que a ovariectomia causa aumento de massa e gordura corporal, levando à menor concentração de adiponectina, e que a RC e o TR alteram estas modificações. / In this study, we evaluated the effect of calorie restriction and strength training on the body weight and insulin sensitivity of ovariectomized rats. Eighty female Holtzman rats were divided into eight groups (n=10 per group): ovariectomized (OVX), ovariectomized plus calorie restriction (OVX-CR), ovariectomized plus strength training (OVX-ST), ovariectomized plus strength training and calorie restriction (OVX-ST+CR), sham operated (SHAM), sham plus calorie restriction (SHAM-CR), sham plus strength training (SHAM-ST), and sham plus strength training and calorie restriction (SHAM-ST+CR). The following variables were analyzed after 13 weeks of intervention: body weight; body fat; blood concentrations of glucose, insulin and adiponectin; total and phosphorylated AKT content; pi3k and Glut 4 (in subcutaneous and retroperitoneal adipose tissues). Ovariectomized rats (OVX, OVX-CR, OVX-ST, and OVX-ST+CR) had a higher body weight and body fat than SHAM animals. Glucose and insulin concentrations were similar in all experimental groups, but adiponectin concentration was lower in the ovariectomized groups (OVX, OVX-CR, OVX-ST, and OVX-ST+CR) when compared to the SHAM group. Calorie restriction and ST increased the concentration of adiponectin when compared to the OVX group. There was no difference between groups in terms of insulin signaling in subcutaneous or retroperitoneal adipose tissue. We conclude that ovariectomy increases body weight and body fat, reducing adiponectin concentration, and that CR and ST alter these modifications.

hjlahgih / Thesis (DPhil (Human Movement Science))--University of Pretoria, 2005. / Biokinetics, Sport and Leisure Sciences / unrestricted