Zellerneuerung

Zellerneuerung is a term used to describe the renewal of cells in living tissues. It encompasses the processes of cell proliferation, differentiation, and the removal of damaged or aged cells, as well as the activity of stem or progenitor cell populations that replenish tissue. The term highlights both routine turnover and regenerative repair after injury, and it varies widely between tissues and life stages.

The renewal process is driven by a network of signaling pathways and microenvironmental cues. Stem cells reside in specialized niches and respond to signals such as Wnt, Notch, Hedgehog, and transforming growth factor beta, along with interactions between cells and the extracellular matrix. Balances between cell division, differentiation, and programmed cell death determine tissue homeostasis and regeneration capacity.

Different tissues exhibit characteristic renewal rates. The epidermis and intestinal lining show high turnover, renewing cells within days to weeks, while the liver can regenerate after injury through cell proliferation. Nervous tissue and certain cardiac tissues have limited regenerative capacity, relying more on remodeling or limited progenitor activity. Factors such as age, nutrition, and disease can influence the rate and quality of Zellerneuerung.

Clinical and research relevance is broad. Impaired Zellerneuerung is linked to aging, chronic wounds, fibrosis, or degenerative diseases, while controlled enhancement of renewal is a key aim in regenerative medicine and cancer biology. Understanding Zellerneuerung helps explain tissue maintenance, healing, and pathological growth in humans.