Cell molting

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Cell turnover , and cell exchange ( Engl. Cell turnover called) is the name for the replacement of differentiated cells through the proliferation of undifferentiated cells.

description

In most of the tissues of the human organism there is a constant, more or less high cell turnover. Especially the highly differentiated cells with high metabolic performance are particularly short-lived and are correspondingly frequently exchanged. In the small intestine, for example, enterocytes and goblet cells - which have an average lifespan of only about 36 hours - are continuously replaced by new undifferentiated cells ( enteric cell molt ). The precursor cells are shifted towards the villi in the course of their short life span , where they differentiate into enterocytes and goblet cells. Then they are broken down by lymphocytes integrated in the epithelium in such a way that the apical third of the cells is rejected into the intestinal lumen. The rest of the cells are broken down in the intestinal mucosa by macrophages . In an adult, around 200 g of intestinal cells are broken down every day and replaced by new cells. Cell molting also takes place during the renewal of the skin and fatty tissue. Tissue in which there is practically no moulting, also called resting tissue, is formed, for example, by nerve cells. Little is known about the mechanisms that coordinate programmed cell death ( apoptosis ) and the division of stem cells differently in the respective organs.

Name origin

The term "cell moulting" is a parallel to the change of plumage in birds ( moulting ).

further reading

Individual evidence

  1. ^ A b G. Egger: The acute inflammation: Fundamentals, pathophysiology and clinical appearances of the unspecific immunity. Verlag Springer, 2005, p. 100. ISBN 3211244913 restricted preview in the Google book search
  2. ↑ W. Graumann: Compact textbook anatomy 3. Schattauer Verlag, 2004, p 104. ISBN 3-794-52063-7 limited preview in Google Book Search
  3. ↑ P. Arner, KL Spalding: Fat cell turnover in humans. In: Biochemical and biophysical research communications Volume 396, Number 1, May 2010, pp. 101-104, ISSN  1090-2104 . doi : 10.1016 / j.bbrc.2010.02.165 . PMID 20494119 . (Review).
  4. ^ R. Sedivy: Page no longer available , search in web archives: Pathology 2. Accessed on April 20, 2011@1@ 2Template: Dead Link / www.sedivy.net
  5. ↑ J. Pellettieri, A. Sánchez Alvarado: Cell turnover and adult tissue homeostasis: from humans to planarians. In: Annual review of genetics Volume 41, 2007, pp. 83-105, ISSN  0066-4197 . doi : 10.1146 / annurev.genet.41.110306.130244 . PMID 18076325 . (Review).