Apolipoprotein D Expression Correlates With Reduced Age-Related Neurodegeneration
Here is an example of the sort of correlations that emerge on a regular basis from human studies of degenerative aging and variations in genes and gene expression:
The lipocalin apolipoprotein D (Apo D) is upregulated in peripheral nerves following injury and in regions of the central nervous system, such as the cerebral cortex, hippocampus, and cerebellum, during aging and progression of certain neurological diseases.In contrast, few studies have examined Apo D expression in the brainstem, a region necessary for survival and generally less prone to age-related degeneration. We measured Apo D expression in whole human brainstem lysates by slot-blot and at higher spatial resolution by quantitative immunohistochemistry. In contrast to cortex, hippocampus, and cerebellum, apolipoprotein D was highly expressed in brainstem tissue from subject with no history of neurological disease, and expression showed little variation with age. Both neurons and glia expressed Apo D, particularly neurons with larger somata and glia in the periphery of these brainstem centers. We propose that strong brainstem expression of Apo D throughout adult life contributes to resistance against neurodegenerative disease and age-related degeneration, possibly by preventing oxidative stress and ensuing lipid peroxidation.