The Arkansan Gut microbiome in healthy aging

The presentation presented the grant proposal of the committee meeting to match the CEMB requirements specifically for doctoral students. The students have to present in front of the committee members and then the professors signed the form and then determine the time of the candidacy exam.

Transcript

1. S The Arkansan gut microbiome in healthy aging Dr. Jiangchao Zhao, Dr. Jeanne Wei, Dr. Gohar Azhar, Dr. Michelle Gray, Dr. Jae Kyeom Kim PROPOSAL COMMITTEE MEETING MAY 17, 2017 SUAD ALGARNI CELL AND MOLECULAR BIOLOGY PROGRAM, ANIMAL SCINCES DEPARTMENT
2. Outline S Introduction S Background S Objective S Material & Methods S Statistical Methods
3. Introduction S The percentage of the older population among Arkansans was 16% in 2014. S In Arkansas, older population (≥65 years old) was 14.4%, ranking number 10 in the United States in 2010. S The most important risk factor for cancer is aging. S By 2030, an estimated 70% of all cancers will occur in adults aged ≥65 years. S The second leading cause of death after heart disease is cancer in Arkansas.
4. Background Gut microbiome play important roles in human health: Ø “educates” the host immune response Ø Protecting against pathogen invasion Ø Regulating intestinal endocrine functions Ø Neurologic signaling Ø Energy biogenesis Ø Eliminating exogenous toxin
5. Microbiota diversity in older adults
6. Model of healthy aging: S Centenarians: Ability to reach the extreme of life by escaping, surviving, or delaying chronic diseases. In Arkansas, it is very important to establish an Arkansan healthy aging cohort q centenarians (≥100 years old) q nonagenarians (≥90 years old) q healthy elderly (≥65 years old)
7. How to define healthy aging? S Healthy ageing defined as those participants who survived without developing any of these four domains: S (1) being free from major chronic disease. S (2) having no major impairment of cognitive function. S (3) having no major limitation of physical functions S (4) having good mental health. Hamer et al,2014
8. Define a healthy gut microbiome in the elderly Intestinal barrier Protect from harmful microorganism or toxin Intestinal permeability Absorb nutrients Response to the trigger present Within the gut
9. Evaluate of healthy aging Functional Independence Measure (FIM) 1- dependent (helper: scores 1–5) 2- independent (no helper: scores 6 –7). The total FIM score is calculated by summing the score of each of the 18 items (White et al, 2011)
10. Evaluate of healthy aging S Mini Nutritional Assessment (MNA) S To assess the nutrition status and diet of elderly. S scoring score:12-14 points: normal nutritional status S 8-11 points: at risk of malnutrition S 0-7 points: Malnourished
11. Evaluate of healthy aging S Activities of Daily Living (ADLS) Instrumental Activities of Daily Living (IADLs) A score of 6 indicates full function, 4 indicates moderate impairment, and 2 or less indicates severe functional impairment (Wallace et al, 2007)
12. Objective 1 S To define a healthy gut microbiome in the Arkansan elderly population. Hypothesis We hypothesize that a core healthy gut microbiome are present in Healthy elderly population in Arkansas.
13. Objective 2 S To identify potential probiotics that promote healthy aging. Hypothesis We hypothesize that beneficial bacteria (i.e.probiotics) are key players in gut homeostasis and could be used to promote healthy aging.
14. How to identify potential probiotics? S Observe more diverse and balanced gut microbiome in healthy aging cohort with enriched beneficial bacteria. Kong, F., et., 2016
15. Objective 3 S To determine gut microbiome dysbiosis in Arkansan elderly with colorectal cancers. Hypothesis We hypothesize that imbalanced, less diverse gut microbiome dominated by certain pathogens are associated with morbidities (e.g. colon cancers) in the elderly.
16. Models of general mechanisms for bacteria associated (or induced) colon cancer Sun, J., et., 2016
17. Material & Methods S Experimental design:
18. Material & Methods S Sample collection: 1. Rectal swab 2. Stool sample 3. Blood sample: Measure systemic inflammation. Cytokines (TNF-α, IL-6, IL-8 and C-reactive protein) By commercial multi-spot microplates Rectum
19. Material & Methods S DNA extraction Rectal swab & Stool sample: S By using a commercial kit S DNA concentration: S Quantify and qualify DNA S PCR amplification & Gel electrophoresis: S Sample validation using by “Universal Bacterial Primer” sequences for the 16S rRNA 27F, 1492R S Validation of amplification of all samples using gel electrophoresis (~1.5 kb band) S
20. Amplicon library construction and sequencing Illumina MiSeq 2 3 250 platform DNA Rectal swab & Stool sample for library preparation and sequencing: PCR using dual barcoded primers and amplification of V4 hypervariable regions of the 16SrRNA. Analyze the pyrosequencing data according to the MiSeq SOP. By using software package mothur v. 1.21 (17) Fadrosh et al. Microbiome 2014
21. Statistical Methods Zhao et al,2012,PNAS,109:5809-5814 Bray-Curtis distances Principal Coordinates Analysis (PCoA) to visualize the changes in community membership and structure based on the Jaccard and Bray-Curtis distance metrices. "Random Forest" package for the R programming. To identify the bacterial species differentially represented between healthy and unhealthy cohorts.
22. Next step S Objective 1: Ø Perform sample collection processing Ø Extract DNA from stool samples and rectal swab Ø Illumina sequencing and data analysis
23. COURSE WORK COMPLETED Courses Credit Hours Grade Received CHEM 5813 BIOCHEMISTRY I 3 A CHEM 619V ADVANCED NANOMATERIALS 3 A CHEM 5843 BIOCHEMISTRY II 3 B CHEG 5113 TRANSPORT PROCESSES I 3 A POSC 5932 CARDIOVASCULAR PHYSIOLOGY 2 A STAT 4373 EXPERIMENTAL DESIGN STAT 4101L INTRODUCTION TO R 3 1 B A BIOL 5873 MICROBIAL GENETICS & INFORMATICS 3 B BIOL 5343 ADVANCED IMMUNOLOGY 3 A Total Credit= 24 hours