Chronic neuroinflammation includes not only long-standing activation of microglia and subsequent sustained release of inflammatory mediators, but also the resulting increased oxidative and nitrosative stress.
Microglia and inflammatory mediators
Murine microglial BV-2 cells are stimulated with LPS for 24h in the presence or absence of a test item (e.g. Ibudilast). The inflammatory response is determined by the release of various cytokines in the supernatant or/and in cell extracts using multiplex cytokine arrays. A huge panel of inflammatory mediators can be detected among these IFN-gamma, IL-1beta, IL-6, IL-10, KC, TNF-alpha.
Figure 1: Immuno-modulatory effects of Ibudilast on various cytokines in LPS stimulated BV-2 cells.
Figure 2: Cytokine detection of organotypic hippocampal brain slices upon LPS stimulation.
Oxidative and nitrosative stress
Therefore, modulation of the prooxidant-antioxidant balance provides a therapeutic option which can be used to improve neuroprotection in response to oxidative stress. Consequently, the role of redox molecules, such as NO and ROS, as key mediators of immunity has renewed attention.
Figure: (Left) Effects of Ibudilast on NO release in LPS stimulated BV-2 cells. (Right) Effects of ascorbic acid on ROS detection in FeCl2 stimulated SH-SY5Y cells.