In the qualitative illustration below, the oxidative footprint
of three biological redox environments is illustrated in gray
shades.
In the young state, the baseline redox potential (A)
and available reducing power are high which squeezes the redox
gradient around an injury, keeping it localized (dark red
footprint). In the middle-age state, the baseline redox
potential (B) has drifted down and the available reducing power
is diminished. This deepens the redox gradient and dramatically
broadens the footprint (medium red) caused by the oxidative
stress at the injury site. In the elderly state, the baseline
redox potential (C) has dropped below the oxidative threshold and
the entire domain (body) is covered by the oxidative footprint
(pink plane). This model provides a rationale for the
increased incidence of autoimmune diseases in aged
individuals.