Research Paper Volume 9, Issue 8 pp 1898—1915
Aging effects on intestinal homeostasis associated with expansion and dysfunction of intestinal epithelial stem cells
- 1 Department of Cell Biology and Physiology, University of North Carolina, Chapel Hill, NC 27599, USA
- 2 Division of Gastroenterology, University of Pennsylvania, Philadelphia, PA 19104, USA
- 3 Department of Molecular Biomedical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27695, USA
- 4 Department of Hematology, Stanford University, Stanford, CA 94305, USA
- 5 Massachusetts General Hospital and Harvard Medical School, Boston, MA 02115, USA
received: January 20, 2017 ; accepted: August 25, 2017 ; published: August 29, 2017 ;https://doi.org/10.18632/aging.101279
How to Cite
Copyright: Moorefield et al. This is an open‐access article distributed under the terms of the Creative Commons Attribution License (CC BY 3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Intestinal epithelial stem cells (IESCs) are critical to maintain intestinal epithelial function and homeostasis. We tested the hypothesis that aging promotes IESC dysfunction using old (18-22 months) and young (2-4 month) Sox9-EGFP IESC reporter mice. Different levels of Sox9-EGFP permit analyses of active IESC (Sox9-EGFPLow), activatable reserve IESC and enteroendocrine cells (Sox9-EGFPHigh), Sox9-EGFPSublow progenitors, and Sox9-EGFPNegative differentiated lineages. Crypt-villus morphology, cellular composition and apoptosis were measured by histology. IESC function was assessed by crypt culture, and proliferation by flow cytometry and histology. Main findings were confirmed in Lgr5-EGFP and Lgr5-LacZ mice. Aging-associated gene expression changes were analyzed by Fluidigm mRNA profiling. Crypts culture from old mice yielded fewer and less complex enteroids. Histology revealed increased villus height and Paneth cells per crypt in old mice. Old mice showed increased numbers and hyperproliferation of Sox9-EGFPLow IESC and Sox9-EGFPHigh cells. Cleaved caspase-3 staining demonstrated increased apoptotic cells in crypts and villi of old mice. Gene expression profiling revealed aging-associated changes in mRNAs associated with cell cycle, oxidative stress and apoptosis specifically in IESC. These findings provide new, direct evidence for aging associated IESC dysfunction, and define potential biomarkers and targets for translational studies to assess and maintain IESC function during aging.