The effects of reducing and oxidizing redox states on cell signaling and cell death. Redox states are a continuum ranging from normal, reducing environments to disrupted, oxidized ones. As redox states shift there is a disruption on the maintenance of normal redox signaling (arrow A). Often, redox states become sufficiently oxidized to induce a number of re-regulation systems to restore cellular redox states to optimal levels and preserve cellular function. However, in cases where redox states are not rapidly restored (arrow B), redox-sensitive elements are perturbed and thus, alter cellular function (short dotted line). When cell signaling fails to regulate important aspects of redox-related cell survival, oxidative damage occurs and there is an increase in cellular apoptosis (arrow C; long dotted line). In disease, redox states that are not sufficiently oxidizing will not promote apoptosis but rather would promote a disruption in cell signaling and function (the area in between arrows A and B).