Regeneraatio

Regeneraatio, or regeneration in Finnish, refers to the regrowth or replacement of damaged or lost tissues, organs, or ecological communities. In biology, regeneraatio describes processes by which organisms restore structure and function after injury or loss. These processes range from simple wound healing to the regrowth of complex body parts and organs, and they vary greatly across species.

In cellular terms, regeneration often involves activation of stem or progenitor cells, dedifferentiation of mature cells, and controlled cell proliferation and differentiation. Pattern formation and tissue remodeling are guided by signaling pathways such as Wnt, Notch, and fibroblast growth factors, as well as by the extracellular matrix and immune signals. Some organisms, notably salamanders, certain fish, and planarian flatworms, can regenerate substantial portions of their bodies, including limbs and organs. In mammals, regeneration is more limited but evident in liver regrowth, skin, bone, and some neural tissues, and regenerative medicine explores ways to extend these capabilities through stem cell therapies, tissue engineering, biomaterials, and gene editing.

Regeneration in medicine aims to repair or replace damaged tissues to restore structure and function, often approaching healing with a goal closer to true regeneration than mere scar formation. Challenges include controlling cell fate, ensuring integration with surrounding tissue, avoiding tumorigenesis, and overcoming immune barriers.

Ecological regeneration describes the recovery of ecosystems after disturbances such as fire, flood, or exploitation. This includes secondary succession, soil stabilization, reestablishment of species, and restoration practices that support resilience and ongoing ecosystem processes. Regeneration science seeks to understand mechanisms, enhance recovery, and apply practices that sustain both health and function of biological systems.