Meta-regulator No.4. Regenerative-niche: a system for maintaining tissue homeostasis through stem cells and their microenvironment

A regenerative-niche regulator is a distributed network of local microenvironments (niches) in which a pool of stem and progenitor cells is maintained, ensuring the renewal of body tissues throughout life. It is based on signaling pathways (Wnt, Notch, Shh, BMP, FGF), growth factors, interaction with the extracellular matrix, and mechanical load. Niche localizations, quantitative parameters (proliferative index, renewal rate, stem cell pool size), and regeneration kinetics are described. The effect on twenty meta-environments of the body has been shown. Pathological conditions in niche depletion (sarcopenia, osteoporosis, fibrosis, slow healing, malignant transformation) and methods of correction (mechanical stimulation, intermittent fasting, modulation of signaling pathways) are considered.