The small bowel microbiome changes significantly with age and aspects of the ageing process

Gabriela Leite; Mark Pimentel; Gillian M Barlow; Ruchi Mathur

doi:10.15698/mic2022.01.768

The small bowel microbiome changes significantly with age and aspects of the ageing process

Microb Cell. 2021 Dec 27;9(1):21-23. doi: 10.15698/mic2022.01.768. eCollection 2022 Jan 3.

Authors

Gabriela Leite¹, Mark Pimentel^{1

2}, Gillian M Barlow¹, Ruchi Mathur^{1

3}

Affiliations

¹ Medically Associated Science and Technology (MAST) Program, Cedars-Sinai, Los Angeles, CA, USA.
² Karsh Division of Gastroenterology and Hepatology, Department of Medicine, Cedars-Sinai, Los Angeles, CA, USA.
³ Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Cedars-Sinai, Los Angeles, CA, USA.

Abstract

Gut microbiome changes have been associated with human ageing and implicated in age-related diseases including Alzheimer's disease and Parkinson's disease. However, studies to date have used stool samples, which do not represent the entire gut. Although more challenging to access, the small intestine plays critical roles in host metabolism and immune function. In this paper (Leite et al. (2021), Cell Reports, doi: 10.1016/j.celrep.2021.109765), we demonstrate significant differences in the small intestinal microbiome in older subjects, using duodenal aspirates from 251 subjects aged 18-80 years. Differences included significantly decreased microbial diversity in older subjects, driven by increased relative abundance of phylum Proteobacteria, particularly family Enterobacteriaceae and coliform genera Escherichia and Klebsiella. Moreover, while this decreased diversity was associated with the 'ageing process' (comprising chronologic age, number of medications, and number of concomitant diseases), changes in certain taxa were found to be associated with number of medications alone (Klebsiella), number of diseases alone (Clostridium, Bilophila), or chronologic age alone (Escherichia, Lactobacillus, Enterococcus). Lastly, many taxa associated with increasing chronologic age were anaerobes. These changes may contribute to changes in human health that occur during the ageing process.

Keywords: age; aging; coliforms; concomitant diseases; medication use; proteobacteria; small intestinal microbiome.

Publication types

Comment

Grants and funding

The authors thank Frank Lee, Joel Levine, the Monica Lester Charitable Trust, and the Elias, Genevieve, and Georgianna Atol Charitable Trust for their generous support of the MAST program.