Advisor: Diane F. Kozireski-Chuback Ph.D.
Assistant: Carl W.F. Bird B.A.; Jonathan Stone

ABSTRACT

In Alzheimer's disease, ß-amyloid plaques activate glial cells and induce the release of high levels of glutamate and nitric oxide (NO). Subsequently, glutamate disrupts neuronal ionic homeostasis and NO causes the formation of lethal doses of oxygen free radicals, resulting in a cascade of neuronal apoptosis. This study tested for the ameliorative effects of statins on BV-2 microglial cells, tested for any effect of statins on iNOS production, and observed mitochondrial behavior in Alzheimer's neurons. We simulated Alzheimer's conditions in BV-2 cells using lipopolysaccharide (LPS), and in neuron cells using glutamate and ß-Amyloid as activators. A fluorescent JC-1 mitochondrial stain was used in neuron cells to determine the effect of malignant activators on mitochondrial distribution. An immunocytochemistry experiment using a combination of a murineainducible nitric oxide synthase antibody and a rabbitamurine IgG bound to FITC as markers was performed to detect iNOS levels after statin application. A nitrite assay was conducted on the prepared microglial cells after treatments with simvastatin, lovastatin, mevastatin, and pravastatin-each statin was added separately. Nitrite assays found that all statins decrease NO levels in glial cells, but particularly simvastatin to a significant extent. Potential reasons might involve simvastatin's structure or behavior. Immunocytochemistry showed that intracellular iNOS levels increased following exposure to statins; therefore, statins did not effectively lower iNOS levels and reduce NO levels elsewhere. Analysis of fluorescent mitochondrial staining showed a higher concentration of mitochondria in the soma as opposed to the neurites under stress (high levels of glutamate/ ß-Amyloid), contrary to our hypothesis. We propose that neurons retract their neurites for ionic and cellular protection under stress.

Keywords : Alzheimer's disease, ß -amyloid plaques, BV-2, glutamate, nitric oxide (NO), statins, iNOS, immunocytochemistry