{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/129751"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/129751","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Effects of soluble corn fiber on cognition in older adults: Integrating clinical, in vitro, and bioinformatics approaches to explore gut-brain interactions","abstract":"Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2027-05-01","abstract_html":"Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2027-05-01","abstract_has_math":false,"creators":["Alvarado, David Anthony"],"institution":"University of Illinois Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Food Science & Human Nutrition","degree_department":null,"school":null,"contributors":["Holscher, Hannah D","Swanson, Kelly S","Khan, Naiman A","Miller, Michael J"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2025,"date_issued":"2025-05-01","date_published":"2025-05-01","updated_at":"2026-07-22T22:25:05Z","subjects":["Gut-Brain","Parabacteroides: Soluble Corn Fiber","Attentional Inhibition","Microbiome"],"languages":["en","eng"],"rights":["Copyright 2025 David Anthony Alvarado"],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://hdl.handle.net/2142/129751","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Holscher, Hannah D","Swanson, Kelly S","Khan, Naiman A","Miller, Michael J"]},{"key":"dc:creator","label":"Author","values":["Alvarado, David Anthony"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2025-05-01","2025-05"]},{"key":"dc:type","label":"Dc Type","values":["text","Thesis"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Food Science & Human Nutrition"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Dissertation"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Ph.D."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Illinois Urbana-Champaign"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Gut-Brain","Parabacteroides: Soluble Corn Fiber","Attentional Inhibition","Microbiome"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["en","eng"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright 2025 David Anthony Alvarado"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://hdl.handle.net/2142/129751"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2027-05-01","The student, David Alvarado, accepted the attached license on 2025-04-29 at 12:44.","The student, David Alvarado, submitted this Dissertation for approval on 2025-04-29 at 12:49.","This Dissertation was approved for publication on 2025-05-01 at 06:35.","DSpace SAF Submission Ingestion Package generated from Vireo submission #22085 on 2025-10-19 at 19:54:39","The gut microbiome is a critical mediator in the optimization of human health through diet. Although robust evidence links dietary fiber consumption to improvements in gastrointestinal and metabolic outcomes, its potential to enhance cognitive function via gut–brain axis pathways remain underexplored. To address this gap, we integrated data from a human clinical trial, in vitro experiments, and multi-omics analyses to elucidate the interconnections among dietary fiber intake, gut microbial dynamics, and cognitive health. For our investigation (Chapter 2), we conducted a randomized crossover clinical trial to evaluate the effects of daily consumption of soluble corn fiber (SCF) for 4 weeks on cognitive function in older adults (45-75 years) and to assess the mediating and moderating influence of the microbiota using 16S rRNA gene-sequenced fecal data on these cognitive outcomes. Next, we sought to further understand if gut bacterium differentially enriched by the intervention could metabolize the SCF in isolation or if the enrichment observed in the clinical trial stems from cross-feeding interactions within the colon. Finally, we examined the microbiome profiles on a subset of participants, categorized as responders and non-responders, using shotgun metagenomic sequencing on their fecal samples to capture snapshots of their microbial functional capacity before and after the intervention, thereby reinforcing the concept of nutrition as a personalized intervention. We discovered that daily consumption of SCF numerically increased fecal acetate, improved attentional inhibition measured by their reaction time, and induced an enrichment of Parabacteroides that exerted a moderating effect. Furthermore, we observed that Parabacteroides distasonis was capable of metabolizing SCF when provided as its sole substrate for growth following an adaptation period, as evidenced by its diauxic growth pattern. In addition, the predicted imputed metagenome of the full cohort suggested increased functional capacity resulting from SCF consumption, and the quantified metagenome demonstrated distinct profiles between responders and non-responders. Together, this integrative approach not only deepens our understanding of the multifaceted roles of SCF but also underscores the importance of incorporating dietary fibers into the diet of older adults as a strategy for harnessing their potential cognitive benefits within personalized nutritional interventions."]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Effects of soluble corn fiber on cognition in older adults: Integrating clinical, in vitro, and bioinformatics approaches to explore gut-brain interactions"]}]}],"canonical_facts":{"dc:contributor":["Holscher, Hannah D","Swanson, Kelly S","Khan, Naiman A","Miller, Michael J"],"dc:creator":["Alvarado, David Anthony"],"dc:date":["2025-05-01","2025-05"],"dc:description":["Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2027-05-01","The student, David Alvarado, accepted the attached license on 2025-04-29 at 12:44.","The student, David Alvarado, submitted this Dissertation for approval on 2025-04-29 at 12:49.","This Dissertation was approved for publication on 2025-05-01 at 06:35.","DSpace SAF Submission Ingestion Package generated from Vireo submission #22085 on 2025-10-19 at 19:54:39","The gut microbiome is a critical mediator in the optimization of human health through diet. Although robust evidence links dietary fiber consumption to improvements in gastrointestinal and metabolic outcomes, its potential to enhance cognitive function via gut–brain axis pathways remain underexplored. To address this gap, we integrated data from a human clinical trial, in vitro experiments, and multi-omics analyses to elucidate the interconnections among dietary fiber intake, gut microbial dynamics, and cognitive health. For our investigation (Chapter 2), we conducted a randomized crossover clinical trial to evaluate the effects of daily consumption of soluble corn fiber (SCF) for 4 weeks on cognitive function in older adults (45-75 years) and to assess the mediating and moderating influence of the microbiota using 16S rRNA gene-sequenced fecal data on these cognitive outcomes. Next, we sought to further understand if gut bacterium differentially enriched by the intervention could metabolize the SCF in isolation or if the enrichment observed in the clinical trial stems from cross-feeding interactions within the colon. Finally, we examined the microbiome profiles on a subset of participants, categorized as responders and non-responders, using shotgun metagenomic sequencing on their fecal samples to capture snapshots of their microbial functional capacity before and after the intervention, thereby reinforcing the concept of nutrition as a personalized intervention. We discovered that daily consumption of SCF numerically increased fecal acetate, improved attentional inhibition measured by their reaction time, and induced an enrichment of Parabacteroides that exerted a moderating effect. Furthermore, we observed that Parabacteroides distasonis was capable of metabolizing SCF when provided as its sole substrate for growth following an adaptation period, as evidenced by its diauxic growth pattern. In addition, the predicted imputed metagenome of the full cohort suggested increased functional capacity resulting from SCF consumption, and the quantified metagenome demonstrated distinct profiles between responders and non-responders. Together, this integrative approach not only deepens our understanding of the multifaceted roles of SCF but also underscores the importance of incorporating dietary fibers into the diet of older adults as a strategy for harnessing their potential cognitive benefits within personalized nutritional interventions."],"dc:format":["application/pdf"],"dc:identifier":["https://hdl.handle.net/2142/129751"],"dc:language":["en","eng"],"dc:rights":["Copyright 2025 David Anthony Alvarado"],"dc:subject":["Gut-Brain","Parabacteroides: Soluble Corn Fiber","Attentional Inhibition","Microbiome"],"dc:title":["Effects of soluble corn fiber on cognition in older adults: Integrating clinical, in vitro, and bioinformatics approaches to explore gut-brain interactions"],"dc:type":["text","Thesis"],"thesis:degree_discipline":["Food Science & Human Nutrition"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."],"thesis:institution_name":["University of Illinois Urbana-Champaign"]},"updated_at":"2026-07-22T22:25:05Z"}