Fig. 2

Time-course of pro- and anti-inflammatory responses. The accepted model of acute inflammation shows the activation and resolution of inflammation that occurs due to pro- and then anti-inflammatory modulators. These processes become dysfunctional during chronic inflammation where the resolution phase is not achieved due to excessive pro-inflammatory signaling. Considering more recent developments in the studies of inflammation, we propose a hypothetical model of inflammation during aging, in which an event is not resolved to a baseline inflammatory level, but leaves some residual pro-inflammatory effects (i.e., microglial priming)