Regional susceptibilities to mitochondrial dysfunctions in the CNS.

Mitochondrial dysfunctions are very common features of age-related neurological diseases such as Parkinson's, Alzheimer's and Huntington's disease. Several studies have shown that bioenergetic impairments have a major role in the degeneration of the central nervous system (CNS) in these patients. Accordingly, one of the main symptoms in many mitochondrial diseases is severe encephalopathy. The heterogeneity of the brain in terms of anatomic structures, cell composition, regional functions and biochemical properties makes the analysis on this organ very complex and difficult to interpret. Humans, in addition to animal models, exposed to toxins that affect mitochondrial function, in particular oxidative phosphorylation, exhibit degeneration of specific regions within the brain. Moreover, mutations in ubiquitously expressed genes that are involved in mitochondrial function also induce regional-specific cell death in the CNS. In this review, we will discuss some current hypotheses to explain the regional susceptibilities to mitochondrial dysfunctions in the CNS.