Molecular, Genetic, and Biochemical Nutrition Commons^™

The Triangular Interaction Between Dietary Polyphenols, Gut Microbiota, And Metabolic Syndrome, Emily Bayliss

Senior Honors Theses

Type 2 diabetes mellitus (T2DM) is a growing global health concern characterized by peripheral insulin resistance as well as impaired insulin secretion from pancreatic β-cells. Emerging evidence suggests that the gut microbiome, specifically gut dysbiosis, an imbalance in the gut microbiome, is a critical modulator of the pathophysiology of T2DM. Dietary polyphenols, a diverse group of bioactive compounds that are abundant in plant-based foods, have recently gained attention for their potential to attenuate metabolic disorders through their antioxidant and anti-inflammatory properties as well as through modulating the composition and activity of gut microbes, thereby attenuating dysbiosis. However, the diabetic state …

Metagenomic Characterization Of Gut Microbiota In Children With Autism Spectrum Disorder: Microbial Signatures And Modulation By Anti-Inflammatory Diet And Probiotics, Marysol Valencia-Buitrago, Rodrigo Dias Oliveira-Carvalho, Valbert Cardoso, Jessica Triviño-Valencia, Luisa Matilde Salamanca-Duque, Vanessa Martínez-Díaz, Jovanny Zabaleta, Narmer Fernando Galeano-Vanegas, Carlos Andrés Naranjo-Galvis

School of Medicine Faculty Publications

Background: Autism Spectrum Disorder (ASD) is increasingly associated with alterations in gut microbiota, intestinal permeability, and immune dysregulation. However, integrative studies exploring these mechanisms in Latin American populations are lacking. Objective: To characterize gut microbiota profiles in Colombian children with ASD and evaluate the effects of two microbiota-targeted interventions, an anti-inflammatory diet and a probiotic formulation, on microbial diversity and taxonomic composition. Methods: In a two-phase study, shotgun metagenomic sequencing was performed on fecal samples from 23 children with ASD and 7 typically developing (TD) controls. In the second phase, 17 children with ASD were randomized to receive a 12-week …

Antimicrobial Eats: How Food Additives Are Contributing To Obesity Via The Gut Microbiome, Olivia Mankos

Senior Honors Theses

The typical modern diet is brimming with food additives used in food processing. Additives such as antibiotic residues, GMOs, pesticide residues, anti-caking agents, emulsifiers, artificial sweeteners, colorants, flavor enhancers, and preservatives. Most of these additives seem to shift the gut microbiome towards more pro-inflammatory signals. When all these additives are considered as an amalgam, such as with the modern processed diet, the ramifications on the gut microbiome are concerning. Obesity, which is characterized by low-level chronic inflammation, is likely exacerbated by these food additives. Consequently, most of these additives should be avoided or banned for optimal health.

Intestinal Microbiome, Fecal Fermentation Profile, And Health Indices In Hiv Infected Men Versus Non-Infected Controls, Mary Andreae, Mary C. Andreae Mrs

Electronic Theses and Dissertations

Many HIV-positive (HIV+) males on Highly Active Anti-Retroviral Therapy (HAART) experience metabolic abnormalities, including Non-Alcoholic Fatty Liver Disease (NAFLD) and lipodystrophy. The intestinal microbiota and short chain fatty acids (SCFA), participate in bidirectional communication with their host. Dysbiosis in HIV+ males on HAART demonstrate a Prevotella-rich enterotype shaped by multiple factors including, medications, adiposity, diet, intestinal permeability, and lifestyle; our objective was to investigate these factors. 19 HIV+ and 21 HIV- males were enrolled. BMI and hip-to-waist ratio (H:W) were obtained, and FibroScan for liver health. Intestinal permeability markers Claudin-21, flagellin, and intestinal fatty acid binding protein (IFABP) in …

Determining The Effects Of Maternal Adiposity On Preterm Neonatal Microbiome And Short Chain Fatty Acid Profiles, Dalton James, William A. Clark Phd, Kristy L. Thomas

Undergraduate Honors Theses

The gut microbiota and its metabolites have vast impacts on the human digestive system, immune system, and health outcomes. Short chain volatile fatty acids (SCVFAs) present in feces can be representative of the interactions of the microbiota present in the gut. Low microbiota diversity in the human gut is highly associated with obesity and adverse health outcomes. Furthermore, the maternal microbiome has a direct impact on neonatal microbiota through various pathways such as environment, skin flora, breast milk composition, and vaginal secretions. This study is aimed to further understand the associations between various factors (maternal adiposity, gestational time, length of …

Evaluation Of Some Toxic Trace Elements In Crocus Sativus L. And Soil Using Neutron Activation Analysis Technique, Ehsan Taghizadeh Tousi

The Philippine Agricultural Scientist

Neutron activation analysis was used in this research to measure the concentrations of aluminum (Al), bromine (Br), chlorine (Cl), mercury (Hg), arsenic (As), and thorium (Th) in soil and saffron plants as well as their contamination, enrichment, and translocation rates. The edible part of the saffron showed a higher Hg concentration than the WHO/FAO-permitted level in the urban area. The soil was not intoxicated and contaminated by Al, As, and Th except in the urban areas, which were slightly polluted by As. The calculated contamination degree and pollution load index indicated that the soil was almost uncontaminated. The enrichment factors …

Assessing The Activity Of Antimicrobial Peptides Against Common Marine Bacteria Located In Rotifer (Brachionus Plicatilis) Cultures, Chelsea Woods, Lindsey Woolley, Gavin Partridge, Mengqi Chen, Evan F. Haney, Robert E.W. Hancock, Nicky Buller, Andrew Currie

Fisheries Research Articles

Rotifers are used as the first feed for marine fish larvae and are grown in large cultures that have high loads of organic matter and heterotrophic bacteria; these bacteria are passed on to the developing fish larvae and can potentially lead to bacterial infections. A modified minimum inhibitory concentration (MIC) protocol for antimicrobial peptides was used to determine the potency of ten antimicrobial peptides (AMPs) in artificial seawater relevant to a rotifer culture (salinity of 25‰) against common marine pathogens. All of the AMPs had antimicrobial activity against the bacterial isolates when the salt concentration was approximately zero. However, in …

Optimized Selenium Status, Gut Microbiota, And Type 2 Diabetes, Ying-Chen Huang

Theses and Dissertations

We have previously demonstrated that long-term dietary Se deficiency in old Terc^-/- mice with humanized telomeres induces type-2 diabetes and exacerbates age-dependent increases in the abundance of A. muciniphila and Lachnospiraceae, which are related to obesity and metabolic syndromes. The objectives of this dissertation are: 1) to determine the minimum intake of Se required for type 2 diabetes prevention in middle-aged mice; 2) to evaluate the efficacy of A. muciniphila and R. torques (a Lachnospiraceae family member) to intervene dietary Se deficiency-induced type 2 diabetes and the underlying mechanisms; 3) to assess sex differences in the responses to …

Recent Advances In Probiotic Application In Animal Health And Nutrition: A Review, Sarayu Bhogoju, Samuel Nahashon

Agricultural and Environmental Sciences Faculty Research

Biotechnological advances in animal health and nutrition continue to play a significant role in the improvement of animal health, growth, and production performance. These biotechnological advancements, especially the use of direct-fed microbials, also termed probiotics, those genetically modified and otherwise, have minimized many challenges facing livestock production around the world. Such advancements result in healthy animals and animal products, such as meat, for a growing population worldwide. Increasing demand for productivity, healthy animals, and consumer food safety concerns, especially those emanating from excessive use of antibiotics or growth promoters, are a driving force for investing in safer alternatives, such as …

Biogeographic Study Of Human Gut-Associated Crassphage Suggests Impacts From Industrialization And Recent Expansion, Tanvi P/ Honap, Krithivasan Sankaranarayanan, Stephanie L. Schnorr, Andrew T. Ozga, Christina Warinner, Cecil M. Lewis Jr.

Anthropology Faculty Research

CrAssphage (cross-assembly phage) is a bacteriophage that was first discovered in human gut metagenomic data. CrAssphage belongs to a diverse family of crAss-like bacteriophages thought to infect gut commensal bacteria belonging to Bacteroides species. However, not much is known about the biogeography of crAssphage and whether certain strains are associated with specific human populations. In this study, we screened publicly available human gut metagenomic data from 3,341 samples for the presence of crAssphage sensu stricto (NC_024711.1). We found that crAssphage prevalence is low in traditional, hunter-gatherer populations, such as the Hadza from Tanzania and Matses from Peru, as compared to …

Non-Invasive Method For Leptin Supplementation In Zebrafish (Danio Rerio), Regan Mcnamara

Williams Honors College, Honors Research Projects

I tested the hypothesis that recombinant leptin protein can be introduced to zebrafish in vivo through non-invasive soaking in a solution containing the protein. One way to study various molecules’ effects in vivo is through intraperitoneal or intracerebroventricular injections during the embryonic or larval stage, which is invasive, difficult to administer, and can have a high mortality rate. 48 hours post fertilization (hpf) zebrafish were soaked in a His-tagged recombinant leptin protein solution at 10 nM and 100 nM concentrations (produced by Genscript). After soaking, zebrafish larvae were washed extensively to remove all recombinant protein on their exterior before homogenization. …

Pyocyanin, A Virulence Factor Produced By Sepsis-Causing Pseudomonas Aeruginosa, Promotes Adipose Wasting And Cachexia, Nika Larian

Theses and Dissertations--Pharmacology and Nutritional Sciences

Sepsis is a leading cause of death among critically ill patients that results in metabolic alterations including hypercatabolism, lipoatrophy, and muscle wasting, contributing to the development of cachexia. Septic cachexia is associated with loss of body weight, fat mass, and lean mass and dysregulated immune function. There are currently no efficacious treatment strategies for septic cachexia, and nutritional interventions have limited success in preventing hypercatabolic wasting. Pyocyanin is a virulence factor produced by sepsis-causing Pseudomonas aeruginosa that has been shown to activate the aryl hydrocarbon receptor (AhR), increase inflammation, and produce reactive oxygen species. Thus, pyocyanin represents a novel mechanistic …

Pcb Disruption Of Gut And Host Health: Implications Of Prebiotic Nutritional Intervention, Jessie Baldwin Hoffman

Theses and Dissertations--Pharmacology and Nutritional Sciences

Exposure to environmental pollutants poses numerous risk factors for human health, including increasing incidence of cardiovascular disease and diabetes. Persistent organic pollutants, such as polychlorinated biphenyls (PCBs) have been strongly linked to the development of these chronic inflammatory diseases and the primary route of exposure is through consumption of contaminated food products. Thus, the gastrointestinal tract is susceptible to the greatest levels of these pollutants and is an important facet to study.

The first two hypotheses of this dissertation tested that exposure to PCBs disrupts gut microbiota directly (in vitro) and within a whole body system. PCB exposure …

Novel Effects Of Prefoldin Pathway On Intestinal Homeostasis Via Dietary Restriction In Drosophila Melanogaster, Jesse Simons

Dissertations, Masters Theses, Capstones, and Culminating Projects

The field of medicine research is embroiled in a battle against aging. Particular focus is on the extension of lifespan and health-span. Lifespan duration is affected by many factors, one of which is the maintenance of the intestines of the organism. Homeostasis of the intestines is controlled by the regulation of intestine cell apoptosis and intestine cell proliferation. My research explores the role of two protein subunits found in a complex which may have possible functions in the regulation of these processes. The overall complex is formed from six subunit proteins, some of which are known to assist in other …

The Antimicrobial, Mechanical, Physical And Structural Properties Of Chitosan-Gallic Acid Films, Xiuxiu Sun, Zhe Wang, Hoda Kadouh, Kequan Zhou

Nutrition and Food Science Faculty Research Publications

Chitosan films incorporated with various concentrations of gallic acid were prepared and investigated for antimicrobial, mechanical, physical and structural properties. Four bacterial strains that commonly contaminate food products were chosen as target bacteria to evaluate the antimicrobial activity of the prepared gallic acid-chitosan films. The incorporation of gallic acid significantly increased the antimicrobial activities of the films against Escherichia coli, Salmonella typhimurium, Listeria innocua and Bacillus subtilis. Chitosan films incorporated with 1.5 g/100 g gallic acid showed the strongest antimicrobial activity. It was also found that tensile strength (TS) of chitosan film was significantly increased when incorporating …

Combined Metagenomic And Phenomic Approaches Identify A Novel Salt Tolerance Gene From The Human Gut Microbiome, Eamon Culligan, Julian R. Marchesi, Colin Hill, Roy D. Sleator

Department of Biological Sciences Publications

In the current study, a number of salt-tolerant clones previously isolated from a human gut metagenomic library were screened using Phenotype MicroArray (PM) technology to assess their functional capacity. PM's can be used to study gene function, pathogenicity, metabolic capacity and identify drug targets using a series of specialized microtitre plate assays, where each well of the microtitre plate contains a different set of conditions and tests a different phenotype. Cellular respiration is monitored colorimetrically by the reduction of a tetrazolium dye. One clone, SMG 9, was found to be positive for utilization/transport of L-carnitine (a well-characterized osmoprotectant) in the …

Control Of Candida Albicans Metabolism And Biofilm Formation By Pseudomonas Aeruginosa Phenazines, Diana K. Morales, Nora Grahl, Chinweike Okegbe, Lars E. P. Dietrich, Nicholas J. Jacobs, Deborah A. Hogan

Dartmouth Scholarship

Candidaalbicanshasdevelopmentalprogramsthatgoverntransitionsbetweenyeastandfilamentousmorphologies and between unattached and biofilm lifestyles. Here, we report that filamentation, intercellular adherence, and biofilm develop- ment were inhibited during interactions between Candida albicans and Pseudomonas aeruginosa through the action of P. aeruginosa-produced phenazines. While phenazines are toxic to C. albicans at millimolar concentrations, we found that lower concentrations of any of three different phenazines (pyocyanin, phenazine methosulfate, and phenazine-1-carboxylate) allowed growth but affected the development of C. albicans wrinkled colony biofilms and inhibited the fungal yeast-to-filament transition. Phenazines impaired C. albicans growth on nonfermentable carbon sources and led to increased production of fer- mentation products (ethanol, glycerol, and …

Microbial Co-Occurrence Relationships In The Human Microbiome, Karoline Faust, J. Fah Sathirapongsasuti, Jacques Izard, Dirk Gevers, Jeroen Raes, Curtis Huttenhower

Department of Food Science and Technology: Faculty Publications

The healthy microbiota show remarkable variability within and among individuals. In addition to external exposures, ecological relationships (both oppositional and symbiotic) between microbial inhabitants are important contributors to this variation. It is thus of interest to assess what relationships might exist among microbes and determine their underlying reasons. The initial Human Microbiome Project (HMP) cohort, comprising 239 individuals and 18 different microbial habitats, provides an unprecedented resource to detect, catalog, and analyze such relationships. Here, we applied an ensemble method based on multiple similarity measures in combination with generalized boosted linear models (GBLMs) to taxonomic marker (16S rRNA gene) profiles …

Adding Upstream Sequence And A Downstream Reporter To The Bile Acid Inducible Promoter Of Clostridium Scindens Vpi 12708, Bryan Patrick Mason

Masters Theses & Specialist Projects

Bile acids in the small intestines of animals serve to breakdown fats and fatsoluble vitamins. Most of the bile acids are reabsorbed into the enterohepatic circulation, but approximately five percent of these bile acids pass into the large intestine. These bile acids are swiftly deconjugated by the bacterial population, and then subjected to further intestinal bacterial chemical modifications. The most significant of these modifications are 7α-dehydroxylations which form secondary bile acids (deoxycholate and lithocholate). Much research has illuminated the 7α-dehydroxylation pathway: of particular interest is the bile acid inducible operon, for which Clostridium scindens VPI 12708 serves as the model …