Our laboratory studies the molecular mechanisms leading to normal brain aging and the pathological processes that culminate in Alzheimer’s disease. We utilize the rhesus monkey as a model for understanding changes that occur during non-pathological aging. With microarray analysis we identified genes that play crucial roles in brain dysfunction leading to cognitive decline. An example is Klotho, a cytoprotective, anti-aging protein. We found that Klotho expression is considerably decreased in the aged brains of monkeys, rats, and mice. We are now working to comprehensively characterize the role of Klotho in normal aging and disease. Our projects are to identify Klotho receptors in the brain and define the signaling pathways by which Klotho exerts its protective effects.