The strong advertising appeal, the search for a good physique, and the improvement in physical performance, has risen the popularity of food supplements and other therapies with slimming supplements based on plant extracts. Since the law exempts food supplements from registration, they are easy targets for importation, commercialization e consumption by the population, which worsens malpractice cases of adulterations. Thus, the objectives of the present work were: research the presence of stimulants in food supplements for both slimming and weight gain; study the addition of synthetic caffeine in natural products based on plants used for weight loss; develop chromatographic methods using HPLC with photodiode detection to detect caffeine, salicin, ephedrine, hordenine, tyramine, octopamine and synephrine (including the L and D enantiomers). The stimulants were separated by reverse phase chromatography using octadecylsilane columns (C18). For L and D synephrine, chromatography with chiral phase of β-cyclodextrin was used. Detection limits varied from 0.02 mg L-1 to 0.35 mg L-1, while quantification limits ranged from 0.07 mg L-1 to 1.16 mg L-1 for the separation of stimulants in food supplements. For analyses of caffeine in herbal products, the LOD and LOQ were 0.048 mg L-1 and 0.16 mg L-1, respectively. For the anlysis of the enantiomers of p-synephrine, the L enantiomer presented a detection limit of 0.11 mg L-1 and quantification limit of 0.36 mg L-1, while the D enantiomer exhibited a detection limit of 0.41 mg L-1 and a quantification limit of 1.36 mg L-1. Each method developed was then applied to the sample, which were, dietary supplement samples (n = 47), herbal products (n = 100), and fruits of Citrus aurantium. Caffeine was the most frequent of the studied stimulants, often exceeding the labeled content and the maximum dose per day recommended (420 mg). The food supplements presented caffeine, synephrine and ephedrine as main stimulants in 53% of the studied samples. / O forte apelo do mercado publicitário, aliado à busca por um corpo padrão e à melhora no desempenho físico faz com que a popularidade dos suplementos alimentares e a associação destes com outras terapias envolvendo compostos emagrecedores a base de plantas seja cada vez maior. A lei que isenta de registro os suplementos alimentares, os torna alvo de fácil importação, comercialização e consumo pela população em geral, agravando ainda a prática de adulteração sobre os mesmos. Logo, este trabalho teve como objetivos: pesquisar a presença de estimulantes em suplementos alimentares para fins de emagrecimento, estudar a incidência de cafeína sintética adicionada em produtos naturais à base de plantas utilizadas para perda de peso; desenvolver métodos cromatográficos emplregando HPLC com detecção com arranjo de fotodiodos (DAD) para a determinação de cafeína, salicina, efedrina, hordenina, tiramina, octopamina e sinefrina (incluindo seus enantiômeros L e D). Os estimulantes foram separados por cromatografia de fase reversa em colunas de octadecilsilano (C18) e os enantiômeros por cromatografia de par iônico com fase quiral de β ciclodextrina. Os limites de detecção (LD) variaram de 0,02 mg L-1 a 0,35 mg L-1, já os limites de quantificação (LQ) ficaram na faixa de 0,07 mg L-1 e 1,16 mg L-1 na separação dos estimulantes em suplementos alimentares. Para as análises de cafeína em produtos naturais a base de plantas, os LD e LQ foram 0,048 mg L-1 e 0,16 mg L-1 respectivamente. Para os enantiômeros da p-sinefrina, o enantiômero L apresentou LD de 0,11 mg L-1 e LQ de 0,36 mg L-1, já o enantiômero D exibiu um LD de 0,41 mg L-1 e LQ de 1,36 mg L-1. Cada método desenvolvido foi posteriormente aplicado em amostras de suplementos alimentares (n=47), produtos naturais à base de plantas (n=100) e fruto de Citrus aurantium. Dos compostos estudados, a cafeína foi a que se apresentou mais frequente, muitas vezes excedendo os teores rotulados nos produtos, ou então a dose máxima recomendada por dia (420 mg). Já os suplementos alimentares apresentaram cafeína, sinefrina e efedrina como principais estimulantes em 53% das amostras estudadas.

No description available.

京都大学 / 新制・課程博士 / 博士(農学) / 甲第25356号 / 農博第2622号 / 新制||農||1109(附属図書館) / 京都大学大学院農学研究科食品生物科学専攻 / (主査)教授 井上 和生, 教授 佐々木 努, 准教授 後藤 剛 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM

In murine and human brown adipose tissue (BAT), mitochondria are powerful generators of heat. Emerging evidence has suggested that the actions of mitochondria extend beyond this conventional biochemical role. In mouse BAT and cultured brown adipocytes, impaired mitochondrial respiratory capacity is accompanied by attenuated expression of Ucp1, a key thermogenic gene, implying a mitochondrial retrograde signaling. However, few have investigated this association in the context of mitochondria-nucleus communication. Using mice with adipose-specific ablation of LRPPRC, a regulator of respiratory capacity, we show that respiration-dependent retrograde signaling from mitochondria to nucleus contributes to transcriptional and metabolic reprogramming of BAT. Impaired respiratory capacity triggers down-regulation of thermogenic and oxidative genes, promoting a storage phenotype in BAT. This retrograde regulation functions by interfering with promoter-specific recruitment of PPARg. In addition, cytosolic calcium may mediate the retrograde signal from mitochondria to nucleus. These data are consistent with a model whereby BAT connects its respiratory capacity to thermogenic gene expression, which in turn contributes to determining its metabolic commitment. Additionally, we find that augmented respiratory capacity activates the thermogenic gene program in inguinal (subcutaneous) white adipose tissue (IWAT) from adipose-specific LRPPRC transgenic mice. When fed a high-fat diet at thermoneutrality, these mice exhibit metabolic improvements as shown by reduced fat mass and improved insulin sensitivity. Furthermore, there is increased recruitment of brown-like adipocytes in IWAT and thus energy expenditure is significantly increased, providing a potential explanation for protection from obesity. These data suggest that augmented respiratory capacity promotes ‘browning’ of IWAT, which has beneficial effects on obesity and diabetes.

No description available.

During embryonic development, adipocytes emerge from microvasculature. Lineage-­‐tracing studies in mice have shown that adipocyte progenitors reside in the adipose tissue capillaries. However, the direct evidence of an association between adipocyte progenitors and vasculature in humans is lacking. A specific class of adipocytes (brown and beige/brite) expresses the uncoupling protein 1 (UCP1), which consumes glucose and fatty acids to generate heat. The abundance of UCP1- containing adipocytes correlates with a lean metabolically healthy phenotype in human. However, a causal relationship between the presence of these cells and metabolic benefits in human is not clear. In this thesis, I report human adipocyte progenitors proliferate in response to pro-angiogenic factors in association with adipose capillary networks in-vitro. The capillary-derived adipocytes transform from being UCP1-negative to positive upon adenylate cyclase activation, a defining feature of the brite/beige phenotype. Activated cells have denser, round mitochondria with UCP1 protein, and display uncoupled respiration. When implanted into NOD-scid IL2rgnull (NSG) mice, the adipocytes can form a vascularized fat pad that induces vascularization and becomes integrated into mouse circulatory system. In normal or high fat diet-fed NSG mice, activated brite/beige adipocytes enhance systemic glucose tolerance and improved hepatic steatosis, thus providing evidence for their potential therapeutic use. The adipocytes also express neuroendocrine and secretory factors such as Interleukin-33, proprotein convertase PCSK1 and proenkephalin PENK, which are correlated with human obesity. Finally, analyses on single-cell clones of capillary-sprout cells reveal the existence of diverse adipogenic progenitor populations. Further characterization of the clones will define the identifying features of the diverse adipocyte progenitor types that exist in human adipose tissue.

Groundwater chemistry on the Niagara Peninsula has been identified as highly mineralized in comparison to groundwaters collected from the same bedrock formations elsewhere in southern Ontario. Three geochemical zones were discerned using hierarchical cluster analysis and other geochemical and isotopic methods. The Escarpment Zone, located along the Niagara and Onondaga Escarpments, is characterized by unconfined aquifer conditions, parameters reflective of surficial contaminants, including road salt, and elevated HCO3, DOC, NO3-, coliform bacteria and tritium. In contrast, in the Salina Zone thick, low-permeability sediments and gypsiferous bedrock results in highly mineralized groundwaters with Ca-SO4 geochemical facies and elevated S2-, Ca2+, Mg2+, K+, Na+, SO42-, Cl-, Br-, Sr2+, NH4+ and CH4. The Guelph Zone contains the lowest electrical conductivity of the three zones and elevated F-. Outliers exist with groundwater geochemistry that differs from the local geochemical zone and the host aquifer. These sites have elevated SO42- (>1000 to 5200 mg/L) with depleted δ34SSO4 (-2.2 to 14.3‰ VCDT) signatures that differs starkly from Devonian and Silurian evaporites (~20 to 32 ‰) in the host formations. This exogenic SO4 was identified in a cross-formational northeast – southwest linear trend crossing three major groundwater flow systems. The lack of down-stream impact in these systems and tritium groundwater ages that are typically only decades old indicate a young, non-geological origin and implicate anthropogenic activities. Additionally, nine samples were identified with elevated methane concentrations and δ13CCH4 signatures within the thermogenic range. As thermogenic methane is not produced within shallow aquifers and would be short-lived in the presence of the ubiquitous sulfate, these samples imply recent upward migration of methane from depth through vertical conduits. Taken together, the evidence supports large-scale upward movement of fluids in the centre of the Niagara geochemical anomaly and more sporadic upward transport of gases over a wider area of the peninsula. The most likely vector is through corroded and leaking casings or boreholes of abandoned (century) gas wells that are common across the peninsula. / Thesis / Master of Science (MSc)