Resource conservation using whole body autophagy: Self-digestion of shedded gut lining cells in the small intestine

  • Lee, Phil Jun (College of Pharmacy and Ajou University) ;
  • Cho, Namki (College of Pharmacy and Research Institute of Drug Development, Chonnam National University) ;
  • Yoo, Hee Min (Microbiological Analysis Team, Group for Biometrology, Korea Research Institute of Standards and Science (KRISS)) ;
  • Chang, Sun-Young (College of Pharmacy and Ajou University) ;
  • Ko, Hyun-Jeong (Laboratory of Microbiology and Immunology, College of Pharmacy, Kangwon National University) ;
  • Kim, Hong Pyo (College of Pharmacy and Ajou University)
  • Received : 2020.03.10
  • Accepted : 2020.04.14
  • Published : 2020.06.30


To retain valuable resources, organisms adopt several strategies including coprophagy. Cells covering the outer skin and internal digestive lumen are actively recycled to maintain their integrity. In present study, we suggested that the small intestine can consume dead cells in a manner similar to how it consumes protein from the diet. We examined the eluates from five segments of the mouse small intestine and cecum and 2 segments of the large intestine and small intestine tissue, and detected immunoreactivity with eukaryotic caveolin-1 and β-actin antibodies only in the cecum and 2 segments from the large intestine. Bacterial agitation of the mouse intestine with Shigella disrupted the architecture and absorptive function of the small intestine. Small intestine eluates were immunoreactive with murine caveolin-1 and contained heme as determined by dot blot analysis. We concluded that the body conserves resources in the small intestine by disposing of and recycling shedded cells.


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