Stressactivated

Stressactivated, or stress-activated, is a term used across disciplines to describe processes that are triggered or intensified by stress. In biology, it often refers to signaling modules that respond to cellular stress and reprogram gene expression. The best-known examples are stress-activated protein kinases (SAPKs), including the JNK and p38 MAP kinase cascades. These kinases are activated by reactive oxygen species, ultraviolet irradiation, heat shock, and inflammatory cytokines. Once activated, they phosphorylate transcription factors such as c-Jun and ATF2, leading to changes in gene expression that influence inflammation, cell cycle arrest, senescence, or apoptosis, depending on cell type and context.

In materials science and chemistry, stress-activated phenomena describe chemical reactions or diffusion processes that occur more readily under mechanical stress. Mechanochemistry, stress-assisted diffusion, and stress-induced phase transformations are examples. Here, stress effectively lowers activation barriers or concentrates energy at defects, enabling reactions or rearrangements that would be unlikely under purely thermal conditions.

In psychology and neuroscience, stress activation refers to the physiological response initiated by perception of threat or demand, most notably the activation of the hypothalamic-pituitary-adrenal axis and the sympathetic nervous system, resulting in the release of cortisol and catecholamines.

The term emphasizes that stress is not merely a trigger but an active driver of certain biological and physical processes, with outcomes ranging from adaptive responses to pathology.