The role of the microbiota in healthy/unhealthy aging

Project Description:

Our immune system and the microbes that live on and in us change as we age, but whether these changes contribute to healthy/unhealthy aging is not clear. We perform mechanistic experiments to understand whether age-related changes in the microbiota or immunes system have a causal relationship with healthy/unhealthy aging.

We have a number of ongoing projects;

  1. Understanding how the gut microbiota changes with age and contributes to a ‘leaky gut’, that triggers inflammation.
  2. Determine if the gut microbiome causes or accelerates frailty
  3. Determine whether the upper respiratory tract microbiota changes with age and whether this contributes to susceptibility to infection.

Team Members:
Technical lead: Erica DeJong (lab manager)
Graduate students: Alice Caldwell (MSc)
Undergraduate students:  Catherine Andary (Medical student)

Current Funding: CIHR Project Grant, Weston Family Foundation Grant

Dr. Michael Surette
Dr. Elena Verdú
Dr. Pratheepa Jeganathan


1. Nasal Tissue Extraction Is Essential for Characterization of the Murine Upper Respiratory Tract Microbiota. Schenck LP, McGrath JJC, Lamarche D, Stämpfli MR, Bowdish DME, Surette MG. mSphere. 2020 Dec 16;5(6):e00562-20. doi: 10.1128/mSphere.00562-20. PMID: 33328347 Free PMC article.
2. The Gut Microbiota and Unhealthy Aging: Disentangling Cause from Consequence. DeJong EN, Surette MG, Bowdish DME. Cell Host Microbe. 2020 Aug 12;28(2):180-189. doi: 10.1016/j.chom.2020.07.013. PMID: 32791111 Review.
3. Single cell and tissue-transcriptomic analysis of murine bladders reveals age- and TNFα-dependent but microbiota-independent tertiary lymphoid tissue formation. Ligon MM, Wang C, DeJong EN, Schulz C, Bowdish DME, Mysorekar IU. Mucosal Immunol. 2020 Nov;13(6):908-918. doi: 10.1038/s41385-020-0290-x. Epub 2020 May 4. PMID: 32366865 Free PMC article.
4. Obesity during pregnancy results in maternal intestinal inflammation, placental hypoxia, and alters fetal glucose metabolism at mid-gestation. Wallace JG, Bellissimo CJ, Yeo E, Fei Xia Y, Petrik JJ, Surette MG, Bowdish DME, Sloboda DM. Sci Rep. 2019 Nov 26;9(1):17621. doi: 10.1038/s41598-019-54098-x. PMID: 31772245 Free PMC article.
5. Starving the Gut: A Deficit of Butyrate in the Intestinal Ecosystem of Children With Intestinal Failure. Dowhaniuk JK, Szamosi J, Chorlton S, Owens J, Mileski H, Clause RF, Pernica JM, Bowdish DME, Surette MG, Ratcliffe EM. JPEN J Parenter Enteral Nutr. 2020 Aug;44(6):1112-1123. doi: 10.1002/jpen.1715. Epub 2019 Oct 22. PMID: 31642067
6. Loss of Microbial Topography Precedes Infection in Infants. Surette MG, Bowdish DME. Am J Respir Crit Care Med. 2019 Sep 15;200(6):660-662. doi: 10.1164/rccm.201903-0687ED. PMID: 30978299 Free PMC article. No abstract available.
7. Microbial dysbiosis and mortality during mechanical ventilation: a prospective observational study. Lamarche D, Johnstone J, Zytaruk N, Clarke F, Hand L, Loukov D, Szamosi JC, Rossi L, Schenck LP, Verschoor CP, McDonald E, Meade MO, Marshall JC, Bowdish DME, Karachi T, Heels-Ansdell D, Cook DJ, Surette MG; PROSPECT Investigators; Canadian Critical Care Trials Group; Canadian Critical Care Translational Biology Group. Respir Res. 2018 Dec 7;19(1):245. doi: 10.1186/s12931-018-0950-5. PMID: 30526610 Free PMC article. Clinical Trial.
8. Commensal microbiota induces colonic barrier structure and functions that contribute to homeostasis. Hayes CL, Dong J, Galipeau HJ, Jury J, McCarville J, Huang X, Wang XY, Naidoo A, Anbazhagan AN, Libertucci J, Sheridan C, Dudeja PK, Bowdish DME, Surette MG, Verdu EF. Sci Rep. 2018 Sep 21;8(1):14184. doi: 10.1038/s41598-018-32366-6. PMID: 30242285 Free PMC article.
9. Streptococcus pneumoniae Colonization Is Required To Alter the Nasal Microbiota in Cigarette Smoke-Exposed Mice. Shen P, Whelan FJ, Schenck LP, McGrath JJC, Vanderstocken G, Bowdish DME, Surette MG, Stämpfli MR. Infect Immun. 2017 Sep 20;85(10):e00434-17. doi: 10.1128/IAI.00434-17. Print 2017 Oct. PMID: 28760931 Free PMC article.
10. On-going Mechanical Damage from Mastication Drives Homeostatic Th17 Cell Responses at the Oral Barrier. Dutzan N, Abusleme L, Bridgeman H, Greenwell-Wild T, Zangerle-Murray T, Fife ME, Bouladoux N, Linley H, Brenchley L, Wemyss K, Calderon G, Hong BY, Break TJ, Bowdish DME, Lionakis MS, Jones SA, Trinchieri G, Diaz PI, Belkaid Y, Konkel JE, Moutsopoulos NM. Immunity. 2017 Jan 17;46(1):133-147. doi: 10.1016/j.immuni.2016.12.010. Epub 2017 Jan 10. PMID: 28087239 Free PMC article.
11. Composition and immunological significance of the upper respiratory tract microbiota. Schenck LP, Surette MG, Bowdish DM. FEBS Lett. 2016 Nov;590(21):3705-3720. doi: 10.1002/1873-3468.12455. Epub 2016 Nov 1. PMID: 27730630 Free PMC article. Review.
12. Streptococcus pneumoniae Colonization Disrupts the Microbial Community within the Upper Respiratory Tract of Aging Mice. Thevaranjan N, Whelan FJ, Puchta A, Ashu E, Rossi L, Surette MG, Bowdish DM. Infect Immun. 2016 Mar 24;84(4):906-16. doi: 10.1128/IAI.01275-15. Print 2016 Apr. PMID: 26787714 Free PMC article.
13. Culture and molecular-based profiles show shifts in bacterial communities of the upper respiratory tract that occur with age. Stearns JC, Davidson CJ, McKeon S, Whelan FJ, Fontes ME, Schryvers AB, Bowdish DM, Kellner JD, Surette MG. ISME J. 2015 May;9(5):1246-59. doi: 10.1038/ismej.2014.250. Epub 2015 Jan 9. PMID: 25575312 Free PMC article.
14. The loss of topography in the microbial communities of the upper respiratory tract in the elderly. Whelan FJ, Verschoor CP, Stearns JC, Rossi L, Luinstra K, Loeb M, Smieja M, Johnstone J, Surette MG, Bowdish DM. Ann Am Thorac Soc. 2014 May;11(4):513-21. doi: 10.1513/AnnalsATS.201310-351OC. PMID: 24601676
15. The impact of respiratory infections and probiotic use on the nasal microbiota of frail residents in long-term care homes. Bowdish DME, Rossi L, Loeb M, Johnstone J, Schenck LP, Fontes M, Surette MG, Whelan FJ. ERJ Open Res. 2023 Sep 25;9(5):00212-2023. doi: 10.1183/23120541.00212-2023. eCollection 2023 Sep. PMID: 37753289 Free PMC article.
16. Effect of Probiotics on Incident Ventilator-Associated Pneumonia in Critically Ill Patients: A Randomized Clinical Trial. Johnstone J, Meade M, Lauzier F, Marshall J, Duan E, Dionne J, Arabi YM, Heels-Ansdell D, Thabane L, Lamarche D, Surette M, Zytaruk N, Mehta S, Dodek P, McIntyre L, English S, Rochwerg B, Karachi T, Henderson W, Wood G, Ovakim D, Herridge M, Granton J, Wilcox ME, Goffi A, Stelfox HT, Niven D, Muscedere J, Lamontagne F, D’Aragon F, St-Arnaud C, Ball I, Nagpal D, Girard M, Aslanian P, Charbonney E, Williamson D, Sligl W, Friedrich J, Adhikari NK, Marquis F, Archambault P, Khwaja K, Kristof A, Kutsogiannis J, Zarychanski R, Paunovic B, Reeve B, Lellouche F, Hosek P, Tsang J, Binnie A, Trop S, Loubani O, Hall R, Cirone R, Reynolds S, Lysecki P, Golan E, Cartin-Ceba R, Taylor R, Cook D; Prevention of Severe Pneumonia and Endotracheal Colonization Trial (PROSPECT) Investigators and the Canadian Critical Care Trials Group. JAMA. 2021 Sep 21;326(11):1024-1033. doi: 10.1001/jama.2021.13355. PMID: 34546300 Free PMC article. Clinical Trial.