The inflammatory cycle and neurodegeneration: Alzheimer’s disease as a case in point. In Alzheimer’s disease, the neuroinflammatory cycle is characterized by sustained activation of microglia and astrocytes in response to activating stimuli, in particular, amyloid beta (A). Glia proinflammatory responses activated by A include induction of cytokines (TNF-, IL-1, S100), chemokines (macrophage inflammatory proteins-1 , : MIP-1, MIP-1), and oxidative stress-related molecules (nitric oxide, NO), which can cause neuronal cell dysfunction and/or death and can further propagate the inflammatory response.