Meta-environment No3: interstitium is a dynamic fluid network of cell-to-cell communication and systemic homeostasis

The interstitium has long been thought to be the passive space between cells. However, in 2018, it was shown to be a continuous, body-wide network of fluid-filled spaces supported by collagen and elastin fibers. In this article, we substantiate that the interstitium is an active meta-medium No3 that meets the criteria of ubiquity, functional integrity, communicative nature, and intrinsic pathology. It serves as an interface between the circulatory and lymphatic systems, provides cytokine transport, intercellular signaling, immune surveillance and is the primary source of lymph. Its structural integrity is regulated by a complex extracellular matrix. Particular attention is paid to the systemic restoration of the interstitium using the Quatotron method, the first engineering system that reproduces the rejuvenating effect of heterochronic parabiosis. Multimodal physical action in combination with biogenic nutrition and longevity mechanics restores hydrostatic pressure, hydration, elasticity and drainage function of the interstitium, normalizes microcirculatory metabolism. Clinical data confirming the effectiveness in the treatment of edema, fibrosis and age-related tissue dehydration are presented. Understanding the interstitium as a meta-environment opens up new opportunities for the treatment of chronic diseases, the prevention of edema and fibrosis, as well as the prolongation of an active life.