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Ileal antimicrobial peptide expression is dysregulated in old age
Sarah Tremblay1, Nathalie Marie Louise Côté1,2, Guillaume Grenier3
1Department of Microbiology and Infectious Diseases, Faculty of Medicine and Health Sciences, Université de Sherbrooke, 3201 rue Jean-Mignault, Sherbrooke, Québec, J1E 4K8 Canada.
Immunity & Ageing : I & A
|September 1, 2017
Summary
Aging disrupts the gut
Area of Science:
- Gastroenterology and Aging Research
Background:
- Gastrointestinal disorders are common in old age.
- Intestinal antimicrobial peptides play a crucial role in gut homeostasis.
Purpose of the Study:
- To investigate changes in intestinal antimicrobial peptide expression in aged mice.
- To understand the link between these changes and age-related gastrointestinal dysfunction.
Main Methods:
- Analysis of ileal antimicrobial peptide gene expression in aged versus young mice.
- Histological examination of the ileal epithelium.
- Assessment of gut microbiota composition.
Main Results:
- Aged mice showed reduced expression of ileal α-defensins and lysozyme.
- Upregulation of Reg3b, Reg3g, β-defensin 1, angiogenin 4, and Relmb was observed in aged mice.
- These changes correlated with ileal epithelial damage and altered microbiota.
Conclusions:
- Dysregulation of antimicrobial peptides is a hallmark of intestinal aging.
- Altered peptide expression may contribute to geriatric gastrointestinal problems.
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