Via ScienceDaily: "Scientists have found that eliminating an enzyme from mice with symptoms of Alzheimer's disease leads to a 90 percent reduction in the compounds responsible for formation of the plaques linked to Alzheimer's disease. ... The key to reducing A-beta peptides was the elimination of an enzyme called jnk3. This enzyme stimulates a protein that produces A-beta peptides, suggesting that when jnk3 activities are high, A-beta peptide production increases - increasing chances for their accumulation and formation into plaques. The researchers also observed that jnk3 activities in brain tissue from Alzheimer's disease patients were increased by 30 to 40 percent when compared to normal human brain tissue. Jnk3 activity typically remains low in the brain, but increases when physiological abnormalities arise. ... [Researchers] deleted jnk3 genetically from Alzheimer's disease model mice carrying the mutations that are found among early-onset Alzheimer's disease patients. In six months, the deletion of the enzyme had lowered A-beta peptide production by 90 percent, which persisted over time, with a 70 percent reduction seen at 12 months in these mice. When the researchers saw that elimination of jnk3 dramatically lowered A-beta peptides in the mice, they also looked for effects on cognitive function at 12 months. The deletion of jnk3 improved cognitive function significantly, reaching 80 percent of normal, while cognitive function in disease model mice was 40 percent of normal. The number of brain cells, or neurons, in the Alzheimer's disease mice was also increased with jnk3 deletion, reaching 86 percent of the value in normal mice, while the neuron numbers were only 74 percent in Alzheimer's model mice."