Fig. 1.

Mitochondrial targets of sirtuin signalling. Depending on the organ and cell type, sirtuins may affect multiple stages of glucose-based energy metabolism, the production of ketone bodies, glutamate usage, or arginine, citrulline, and polyamine biosynthesis. While numerous metabolites have direct roles in the CNS, others not produced locally, may dramatically impact brain health (as in the case of e.g. urea cycle, which is typically incomplete in the central neurons, but its deregulation in peripheral tissues leads to neurodegeneration in the CNS). According to [40], modified