Figure 2.
Mechanisms underlying the neuroprotective effects of ketone bodies. Ketone bodies improve mitochondrial respiration and, as a result, increase NAD levels relative to NADH, decrease reactive oxygen species (ROS) formation and enhance ATP production. Ketone bodies also decrease the activity of the apoptotic enzyme protein phosphatase 2A (PP2A), possibly by inhibiting the ROS-dependent formation of ceramide, a PP2A activator. Sirt1 involvement is possible given the increased NAD to NADH ratio, but this has yet to be demonstrated.