fibrogenese

Fibrogenese, or fibrogenesis, is the biological process by which fibrous tissue is produced, involving the synthesis, deposition, and remodeling of extracellular matrix components, particularly collagens, during wound healing and in fibrotic diseases. It occurs in many tissues and is driven by interactions among resident cells, inflammatory cells, and signaling molecules.

A central feature of fibrogenesis is the activation of fibroblasts and certain resident cells, such as hepatic stellate cells in the liver, into myofibroblasts that synthesize and secrete extracellular matrix. Key signaling pathways, including transforming growth factor-beta (TGF-β), platelet-derived growth factor (PDGF), and connective tissue growth factor (CTGF), promote this activation. Matrix remodeling enzymes, such as matrix metalloproteinases (MMPs) and their inhibitors (TIMPs), regulate the balance between deposition and degradation of matrix.

Fibrogenesis proceeds through phases. Injury or inflammation initiates recruitment of immune cells and cytokines; fibroblasts proliferate and produce matrix; and remodeling leads to scar maturation. In normal wound healing, fibrogenesis is largely transient and resolves as tissue architecture is restored. In chronic or excessive injury, ongoing fibrogenesis can result in pathological fibrosis, with progressive scar formation, tissue stiffening, and potential loss of organ function.

Fibrogenesis has been observed in multiple organs, including the liver (hepatic fibrosis), lungs (fibrosis such as idiopathic pulmonary fibrosis), skin, and kidneys. Diagnosis often relies on histologic assessment of collagen deposition and imaging or circulating biomarkers of collagen turnover. Understanding fibrogenesis informs strategies aimed at interrupting fibrotic signaling and limiting organ dysfunction.