Boosting Repair Mechanisms Beneficial in Alzheimer's
One might expect that improving repair and maintenance systems in the brain would provide some benefit irrespective of how present damage came about, and this may be the case: "The granulocyte-colony stimulating factor (GCSF) significantly reduced levels of the brain-clogging protein beta amyloid deposited in excess in the brains of the Alzheimer's mice ... The growth factor prodded bone-marrow derived microglia outside the brain to join forces with the brain's already-activated microglia in eliminating the Alzheimer's protein from the brain. Microglia are brain cells that act as the central nervous system's main form of immune defense. Like molecular 'Pac-men,' they rush to the defense of damaged or inflamed areas to gobble up toxic substances." This is still a rearguard action against end-stage consequences, however - the underlying chain of causes is not addressed. Repair of final consequences isn't a viable long-term strategy for dealing with an ever-worsening root cause, as those consequences will rapidly exceed the ability to repair them. At some point you have to address the origin of the problem in order to prevent it from spiraling out of control.
Link: http://www.sciencedaily.com/releases/2009/07/090701160557.htm