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Description
Cardiovascular disease and diabetes are major health burdens. Diabetes is a primary risk factor of cardiovascular disease, and there is a strong link between obesity and risk of developing diabetes. With the prevalence of prediabetes highest among overweight/obese individuals, investigation into preventative strategies are needed. Aerobic exercise is a potent stimulus for both insulin and non-insulin dependent glucose uptake into the skeletal muscle. A single exercise session can improve insulin sensitivity within hours after exercise. The effects of intensity, type, and volume of exercise on glucose homeostasis have been studied extensively; however, controlling for muscle contraction frequency with a constant exercise intensity and workload has not been examined. The purpose of this study was to compare muscle contraction frequency during aerobic exercise by altering cycling cadence on insulin sensitivity and vascular health. Eleven obese males (age=28yr, BMI=35kg/m2) completed three conditions in random order: 1) control-no exercise; 2) 45-min cycling at 45 revolutions per minute (45RPM) at 65-75%VO2max; 3) 45-min cycling at 90RPM at 65-75%VO2max. Glucose control and insulin sensitivity were assessed with oral glucose tolerance tests (OGTT) 4 hours post-exercise. Vascular health was assessed via flow-mediated dilation (FMD) pre-exercise, 1-hr and 2-hr post exercise and ambulatory blood pressure was assessed pre-exercise, and continually every 15 min post-exercise. Linear mixed models were used to compare the mean differences in outcome variables. There were no significant differences found between control and both exercise conditions for all OGTT outcomes and no differences were found between control and exercise in FMD (all, p>0.05). Significant effects for exercise were found for both brachial and central blood pressure measures. Brachial systolic blood pressures were lower at 2- and 4-hr post-exercise by approximately -10 and -8mmHg, respectively (p<0.001 and p=0.004) versus control. Central systolic blood pressures were lower at 2-, 3-, and 4-hr post-exercise by approximately -8, -9 and -6mmHg, respectively (p<0.001, p=0.021 and p=0.004) versus control. In conclusion, aerobic exercise, regardless of muscle contraction frequency, were unable to effect glucose control and insulin sensitivity. Similarly, there was no effect on vascular function. However, there was a significant effect of aerobic exercise on reducing post-exercise blood pressure.
ContributorsJarrett, Catherine Lee (Author) / Gaesser, Glenn A (Thesis advisor) / Angadi, Siddhartha S (Committee member) / Dickinson, Jared M (Committee member) / Whisner, Corrie M (Committee member) / Todd, Michael W (Committee member) / Arizona State University (Publisher)
Created2017
Description
No studies have evaluated the impact of tracking resting energy expenditure (REE) and modifiable health behaviors on gestational weight gain (GWG). In this controlled trial, pregnant women aged >18 years (X=29.8±4.9 years) with a gestational age (GA) <17 weeks were randomized to Breezing™ (N=16) or control (N=12) for 13 weeks. The Breezing™ group used a real-time metabolism tracker to obtain REE. Anthropometrics, diet, and sleep data were collected every 2 weeks. Rate of GWG was calculated as weight gain divided by total duration. Early (GA weeks 14-21), late (GA weeks 21-28), and overall (GA week 14-28) changes in macronutrients, sleep, and GWG were calculated. Mediation models were constructed using SPSS PROCESS macro using a bootstrap estimation approach with 10,000 samples. The majority of women were non-Hispanic Caucasian (78.6%). A total of 35.7% (n=10), 35.7% (n=10), and 28.6% (n=8) were normal weight, overweight, and obese, respectively, with 83.3% (n=10) and 87.5% (n=14) of the Control and Breezing™ groups gaining above IOM GWG recommendations. At baseline, macronutrient consumption did not differ. Overall (Breezing™ vs. Control; M diff=-349.08±150.77, 95% CI: -660.26 to -37.90, p=0.029) and late (M diff=-379.90±143.89, 95% CI:-676.87 to -82.93, p=0.014) changes in energy consumption significantly differed between the groups. Overall (M diff=-22.45±11.03, 95% CI: -45.20 to 0.31, p=0.053), late (M diff=-23.16±11.23, 95% CI: -46.33 to 0.01, p=0.05), and early (M diff=20.3±10.19, 95% CI: -0.74 to 41.34, p=0.058) changes in protein differed by group. Nocturnal total sleep time differed by study group (Breezing vs. Control; M diff=-32.75, 95% CI: -68.34 to 2.84, p=0.069). There was a 11.5% increase in total REE throughout the study. Early changes in REE (72±211 kcals) were relatively small while late changes (128±294 kcals) nearly doubled. Interestingly, early changes in REE demonstrated a moderate, positive correlation with rates of GWG later in pregnancy (r=0.528, p=0.052), suggesting that REE assessment early in pregnancy may help predict changes in GWG. Changes in macronutrients did not mediate the relationship between the intervention and GWG, nor did sleep mediate relationships between dietary intake and GWG. Future research evaluating REE and dietary composition throughout pregnancy may provide insight for appropriate GWG recommendations.
ContributorsVander Wyst, Kiley Bernhard (Author) / Whisner, Corrie M (Thesis advisor) / Reifsnider, Elizabeth G. (Committee member) / Petrov, Megan E (Committee member) / Buman, Matthew (Committee member) / Shaibi, Gabriel Q (Committee member) / Arizona State University (Publisher)
Created2019
Description
Introduction: Cystic fibrosis (CF) is the most common life-shortening autosomal recessive genetic disease affecting Caucasians. The disease is characterized by a dysfunctional cystic fibrosis transmembrane regulator (CFTR) protein and aberrant mucus accumulation that subsequently alters the physicochemical environment in numerous organ systems. These mucosal perturbations have been associated with inflammation and microbial dysbiosis, most notably in the lungs and gastrointestinal (GI) tract. Genistein, a soy isoflavone and dietary polyphenol, has been shown to modulate CFTR function in cell cultures and murine models, as well exert sex-dependent improvement of survival rates in a CF mouse model. However, it is unknown whether dietary genistein affects gut microbiome diversity and community structure in cystic fibrosis. This study sought to examine associations between dietary genistein treatment and gut microbiome diversity and community structure in a murine model of CF. Methods: Twenty-four male and female mice homozygous for the DF508 CFTR gene mutation were maintained on one of three diet regimens for a 45-day period (n=11, standard chow; n=7, Colyte-treated water and standard chow; n=6, 600 mg dietary genistein per kg body weight). One fecal pellet was collected per mouse post-treatment, and microbial genomic DNA was extracted from the fecal samples, quantified, amplified, and sequenced on the Illumina MiSeq platform. QIIME 2 was used to conduct alpha- and beta-diversity analyses on all samples. Results: Measures of alpha-diversity were significantly decreased in the dietary genistein group as compared to either standard chow or Colyte groups. Measures of beta-diversity showed that community structure differed significantly between dietary treatment groups; these differences were further illustrated by distinct clustering of taxa as shown by principal coordinates analysis plots. Conclusion: This 3-arm parallel experimental study showed that dietary genistein treatment was associated with decreased microbial diversity and differences in microbial community structure in DF508 mice.
ContributorsArgo, Katy Bryana (Author) / Whisner, Corrie M (Thesis advisor) / Al-Nakkash, Layla (Committee member) / Sweazea, Karen L (Committee member) / Arizona State University (Publisher)
Created2019
Description
Background: Nearly 95% of Americans will develop hypertension, and 67% will not seek treatment. Furthermore, hypertension is the leading risk factor for coronary heart disease. While previous studies have increased the use of blood pressure medication among patients that have received hypertension education, medications may not work for everyone. Due to the life-threatening nature of this condition, it is essential to find an effective alternative for treatment. The purpose of this study was to examine the impact of organometallic complex supplementation on hypertension and left ventricular hypertrophy in 6-week old male Sprague-Dawley rats that were fed either standard rodent chow or a high fat diet for 10 weeks at a university in Arizona.
Methods: Forty-two healthy six-week old male Sprague-Dawley rats were randomly assigned to one of three groups: plain water control, 0.6 mg/ml organometallic complex or 3.0 mg/ml organometallic complex as soon as they arrived. Each rat was then housed individually to prevent the sharing of microbiota through coprophagia. Rats in each treatment group were further divided into two dietary groups that were fed either a high fat diet containing 60% kcal fat that was changed every three days or standard rodent chow. Researchers were not blind to which rat was in each group. At the end of the 10-week study, rats were euthanized with an overdose of sodium pentobarbital (200 mg/kg, i.p.). Heart, left ventricle of the heart, liver, and spleen masses were recorded for each animal. Data were analyzed by two-way ANOVA using SigmaPlot 10.0 software.
Results: At the conclusion of this study, the left ventricle mass of the rats in the high fat diet group were significantly larger than those in the chow group. Neither dose of the organometallic complex supplement prevented these effects induced by high fat feeding.
Conclusion: The organometallic complex supplement was not effective at mitigating the effects of a high fat diet on cardiac hypertrophy in rats. Therefore, this supplement should not be used to treat cardiac hypertrophy.
Methods: Forty-two healthy six-week old male Sprague-Dawley rats were randomly assigned to one of three groups: plain water control, 0.6 mg/ml organometallic complex or 3.0 mg/ml organometallic complex as soon as they arrived. Each rat was then housed individually to prevent the sharing of microbiota through coprophagia. Rats in each treatment group were further divided into two dietary groups that were fed either a high fat diet containing 60% kcal fat that was changed every three days or standard rodent chow. Researchers were not blind to which rat was in each group. At the end of the 10-week study, rats were euthanized with an overdose of sodium pentobarbital (200 mg/kg, i.p.). Heart, left ventricle of the heart, liver, and spleen masses were recorded for each animal. Data were analyzed by two-way ANOVA using SigmaPlot 10.0 software.
Results: At the conclusion of this study, the left ventricle mass of the rats in the high fat diet group were significantly larger than those in the chow group. Neither dose of the organometallic complex supplement prevented these effects induced by high fat feeding.
Conclusion: The organometallic complex supplement was not effective at mitigating the effects of a high fat diet on cardiac hypertrophy in rats. Therefore, this supplement should not be used to treat cardiac hypertrophy.
ContributorsMcCormick, Kelly Ann (Author) / Sweazea, Karen L (Thesis advisor) / Whisner, Corrie M (Committee member) / Alexon, Christy (Committee member) / Arizona State University (Publisher)
Created2019
Description
Most American children consume less than the recommend amount of fruits and vegetables (F&V), 74% and 84%, respectively. Eating too few F&V in childhood is associated with increased risk of cardiovascular disease, hypertension, respiratory symptoms, and some cancers later in life. Adequate F&V consumption favorably impacts antioxidant status, gut flora, mood, and cognitive functioning. Nutrients such as vitamin C and fiber are only naturally occurring in plant foods. For many children, school lunches are an important source of F&V. This pilot study assessed the feasibility of providing condiments to increase children’s consumption of salad bar F&V in an elementary school cafeteria at lunchtime. The trial site was a single Title 1 elementary school in a large, urban district in the greater Phoenix metropolitan area. Taste tests were conducted on three convenience samples of children in grades 3 – 7, aged 8 – 12 years (n=57) to identify the most popular condiment flavors. The five highest rated flavors were made available daily at a “flavor station” in the school’s lunchroom for three consecutive weeks during the Fall 2018 semester. Descriptive and inferential statistics were used to analyze data. A cost analysis was conducted for capital outlays related to the flavor station. School employee perceptions of F&V and the flavor station were assessed via posttest online surveys. Peanut butter was rated the best tasting condiment by children and was the only condiment that increased in popularity throughout the intervention. Overall, daily F&V consumption increased 17 g per child. There was a linear increase in F&V consumption during the study (r=0.986; P=0.014). As a proportion of the total F&V selected, F&V waste decreased by nearly 3%. The average daily cost of providing the flavor station was $0.09 per student. Sixty-five percent of school staff felt that the flavor station should continue at their school. Peanut butter is an affordable, nutrient-dense food that accommodates the USDA Food and Nutrition Service meal patterns and nutrition standards, and thus, is a viable strategy for increasing F&V consumption and decreasing F&V waste. The results herein inform the development of future interventions to improve the palatability of F&V for children.
ContributorsScholtz, Cameron (Author) / Johnston, Carol (Thesis advisor) / Alexon, Christy (Committee member) / Hooker, Steven (Committee member) / Schwake, David (Committee member) / Swan, Pamela (Committee member) / Wharton, Christopher (Christopher Mack), 1977- (Committee member) / Arizona State University (Publisher)
Created2019
Description
The winter holiday period has been highlighted as a major risk period for weight gain due to excess caloric intake in the form of fat and sugar. Furthermore, diets high in fat and sugar have been implicated in the pathogenesis of diabetes and cardiovascular disease. Exercise aids in the prevention of weight/fat gain, and prevents deleterious changes in cardiometabolic function. The objective of this study was to examine the effects of a fat-sugar supplemented diet, with and without two different exercise training protocols, on body composition, glycemic control and other markers of cardiovascular disease in an at-risk population of overweight and obese males. Twenty-seven, healthy overweight/obese (BMI >25 kg/m2) males were fed 2 donuts per day, 6 days/week, for four weeks, while maintaining their current diet. In addition, all subjects were randomized to one of the following conditions: sedentary control, 1,000 kcal/week moderate-intensity continuous training (MICT) (50% of peak oxygen consumption), or 1,000 kcal/week high-intensity interval training (HIIT) (90-95% of peak heart rate). Supervised exercise training was performed 4 days/week on a cycle ergometer. Changes in body weight and composition, endothelial function, arterial stiffness, glycemic control, blood lipids and cardiorespiratory fitness (CRF) were assessed before and after the intervention. Body weight, lean mass and visceral fat increased significantly in HIIT (p<0.05) and were unchanged in MICT. There was a trend for a significant increase in body weight (p=0.07) and lean mass (p=0.11) in control. Glycemic control during the 2-h OGTT improved significantly in MICT and control, with no change in HIIT. Hepatic insulin resistance index (IRI) and 30-min insulin during the OGTT improved significantly after MICT and worsened following control (p=0.03), while HIIT was unchanged. CRF increased significantly in both HIIT and MICT, with no change in control (p<0.001). There were no significant changes in other markers of cardiovascular disease. The addition of a fat-sugar supplement (~14,500 kcal) over a 4-week period was not sufficient to induce deleterious changes in body composition and cardiometabolic health in overweight/obese young males. Exercise training did not afford overweight/obese males additional health benefits, with the exception of improvements in fitness and hepatic IRI.
ContributorsTucker, Wesley Jack (Author) / Gaesser, Glenn A (Thesis advisor) / Angadi, Siddhartha S (Committee member) / Whisner, Corrie M (Committee member) / Buman, Matthew P (Committee member) / Shaibi, Gabriel (Committee member) / Arizona State University (Publisher)
Created2016
Description
The transition to college has been identified as a vulnerable period for weight gain and the onset of obesity. Research has shown that the gut microbiota is different in obese compared to lean individuals, but a period of weight gain has never been studied in free-living individuals. The objective of this longitudinal, observational study was to assess the association between changes in the intestinal microbiota and weight-related outcomes in healthy college students living in on-campus dormitories at Arizona State University (n=39). Anthropometric measures and fecal samples were collected at the beginning and end of the school year, and microbial relative abundance for A. muciniphila, F. prausnitzii, R. gnavus, and L. acidophilus was measured through qPCR analyses. In this population, body mass index (BMI) and waist circumference (WC) increased by 0.97 ± 1.28 kg/m2 and 2.64 ± 4.90 cm, respectively. Wilcoxon-Rank tests revealed that R. gnavus fold change was significantly different between groups of weight loss/maintenance and weight gain ≥ 5% body weight (0.14 [-0.21, 0.64], n=24 vs. -0.14 [-0.92, 0.05], n=15, respectively; p=0.028). Correlation analyses suggested a significant negative association between A. muciniphila fold change and both % WC change and % BMI change (r= -0.66; p<0.01 and r= -0.33; p=0.04, respectively). However, multivariate regression analysis controlling for sex and race/ethnicity showed a significant association between A. muciniphila and % WC change, but not % BMI change (R2= 0.53; p<0.01 and R2= 0.24; p=0.15). F. prausnitzii was not associated with weight-related outcomes in this sample. L. acidophilus was excluded from study analyses after subsequent qPCR trials revealed no amplification in participant samples. Overall, this was the first study to show a relationship between A. muciniphila fold change and weight-related outcomes over a period of weight gain. Specifically, A. muciniphila was strongly negatively associated with WC in this sample. Further research is needed to more accurately describe these associations and potential mechanisms associated with the shift in gut microbiota observed with weight gain. Findings from future research may be used to develop interventions for college students aiming to shift the gut microbiota to prevent weight gain.
ContributorsJourney, Elizabeth (Author) / Whisner, Corrie M (Thesis advisor) / Bruening, Meredith (Committee member) / Sweazea, Karen (Committee member) / Arizona State University (Publisher)
Created2017
Description
Vitamin D is a nutrient that is obtained through the diet and vitamin D supplementation and created from exposure to Ultraviolet B (UVB) radiation. While there are many factors that determine how much serum 25-hydroxyvitamin D (25(OH)D) concentration is in the body, little is known about how genetic variation in vitamin D-related genes influences serum 25(OH)D concentrations resulting from daily vitamin D intake and exposure to direct sunlight. Previous studies show that common genetic variants rs10741657 (CYP2R1), rs4588 (GC), rs228678 (GC), and rs4516035 (VDR) act as moderators and alter the effect of outdoor time and vitamin D intake on serum 25(OH)D concentrations. The objective of this study is to analyze the associations between serum 25(OH)D concentrations resulting from outdoor time and vitamin D intake, and genetic risk scores (GRS) established from previous studies involving single nucleotide polymorphisms (SNP) located on or near genes involving vitamin D synthesis, transport, activation, and degradation in 102 Hispanic and Non-Hispanic adults in the San Diego County, California. This study is a secondary analysis of data from the Community of Mine study. Global Positioning System (GPS) data collected by the Qstarz GPS device worn by each participant was used to measure outdoor time, a proxy measurement for sun exposure time. Vitamin D intake was assessed using two 24-hour dietary recalls. Blood samples were measured for serum 25(OH)D concentrations. DNA was provided to assess each participant for the various genetic variants. Adjusted analyses of the GRS and serum 25(OH)D concentrations showed that individuals with high GRS (3-4) had lower serum 25(OH)D concentrations than individuals with low GRS (0-2) for both Nissen GRS and Rivera-Paredez GRS.
ContributorsAnderson, Heather Ray (Author) / Sears, Dorothy (Thesis advisor) / Alexon, Christy (Committee member) / Dinu, Valentin (Committee member) / Jankowska, Marta (Committee member) / Arizona State University (Publisher)
Created2022
Description
Objective: This research examined the impact of daily ingestions of commercial high protein nutrition bars (with or without added fiber) on 24-h energy intake and satiety
for one week among free-living young healthy adults.
Design: In a 4-week double-blind, randomized crossover trial, 21 normal and
overweight participants (Mean BMI 23.9 ± 2.7 kg/m²), free of chronic diseases, were
randomized assigned to HP (high protein: 21 g protein) or HPHF (high protein high fiber:
20g, 14 g fiber) nutrition bars. Participants were included in the trial if they meet the
criteria for non-smoking, and not taking prescribed medication for chronic diseases.
Participants were instructed to consume commercial nutrition bars daily for seven
consecutive days. Body composition was measured with a bioelectrical impedance scale
at weeks 1, 3, and 5. Dietary data was recorded by the MyFitnessPal app on Wednesday,
Friday, and Sunday of each week.
Results: The mean energy intake for the weeks HPHF bars were consumed is
significantly higher compared to baseline (1998 ± 534 vs. 1806 ± 537 respectively; p =
0.035). The mean fat mass following one week of HPHF bar consumption was
significantly higher than the baseline value (18.8 ± 6.8 vs. 18.3 ± 6.7 respectively; p =
0.023) and trended higher (18.8 ± 6.8 vs. 18.3 ± 6.7 respectively; p = 0.057) in
comparison to the value following one week of HP bar consumption. For the high
physical activity level group (n = 10), the mean energy intakes for the baseline week and
the weeks the HP and HPHF bars were consumed were 1883 ± 597 kcal, 2154 ± 712 kcal,
and 2099 ± 603 kcal respectively (p ˂ 0.04; energy intakes for both bars were
significantly different from baseline). Nutrient intakes differed significantly mirroring the
nutrient profile for each specific bar. There are significant effects after both bars on
satiety, but there were no differences between each bar.
Conclusions: Sales of nutrition bars gained rapid growth and may represent a
unique source for specific nutrients. However, ingestion of commercial high protein
nutrition bars may increase the risk of gaining fat mass and eventual body mass over
time.
ContributorsPang, Minghan (Author) / Johnston, Carol (Thesis advisor) / Shepard, Christina (Committee member) / Alexon, Christy (Committee member) / Arizona State University (Publisher)
Created2022
Description
High fiber diets have been associated with improved cardiometabolic health with specific efforts to lower circulating levels of low-density lipoprotein (LDL cholesterol). Whole grain and grain-based foods are major contributors of dietary fiber in the American diet, of which wheat has been extensively studied. Corn, however, has not been well studied for its cholesterol-lowering properties. Further, the mechanisms by which grains improve cardiometabolic health require further exploration with regard to the human microbiome. The objective of this single-blind randomized controlled, crossover trial was to assess the impact of three different corn flours (whole grain, refined, and bran-enhanced refined flour mixture) on serum LDL cholesterol and the gut microbiota diversity and composition. Twenty-three participants were recruited, between the ages of 18-70 with hypercholesterolemia (Male = 10, Female = 13, LDL >120 mg/dL) who were not taking any cholesterol-lowering medications. Participants consumed each flour mixture for 4 weeks prepared as muffins and pita breads. At the beginning and end of each 4-week period serum for cholesterol assessment, anthropometrics, and stool samples were obtained. Serum cholesterol was assessed using a clinical analyzer. Stool samples were processed, and microbial DNA extracted and sequenced based on the 16S rRNA gene. A generalized linear model demonstrated a significant treatment effect (p=0.016) on LDL cholesterol and explained a majority of the variance (R-squared= 0.89). Post hoc tests revealed bran-enhanced refined flour had a significant effect on cholesterol in comparison to whole grain flour (p=0.001). No statistically significant differences were observed for gut microbial community composition (Jaccard and weighted Unifrac) after corn consumption. However, relative abundance analysis (LEfSE) identified Mycobacterium celatum (p=0.048 FDR=0.975) as a potential marker of post-corn consumption with this microbe being differentially less abundant following bran-enhanced flour treatment. These data suggest that corn flour consumption may be beneficial for individuals with hypercholesterolemia but the role of gut microbiota in this relationship requires further exploration, especially given the small sample size. Further research and analysis of a fully powered cohort is needed to more accurately describe the associations and potential mechanisms of corn-derived dietary fiber on circulating LDL cholesterol and the gut microbiota.
ContributorsWilson, Shannon L (Author) / Whisner, Corrie M (Thesis advisor) / Sears, Dorothy (Committee member) / Buman, Matthew (Committee member) / Dickinson, Jared (Committee member) / Zhu, Qiyun (Committee member) / Arizona State University (Publisher)
Created2022