Effect of Sulindac in an in vitro AD Model Under hypoxic conditions

BACKGROUND: Alzheimer's Disease (AD) continues to be the most prevalent form of senile dementia without any significant therapy. Oxidative damage and hypoxia are known to play a major role in the pathology of AD. Hypoxia increases production of ß amyloid (Aß) plaques and dysfunction in tau proteins which leads to neuronal death by increasing reactive oxidative species (ROS) formation. Furthermore, Aß derived from the proteolytic cleavage of β-amyloid precursor protein (APP) acts as a biomarker of AD. It is known that in an APP transgenic mice model of AD exhibits oxidative damage suggesting that a possible therapeutic approach would be to protect neuronal cells against oxidative damage. Our laboratory has shown previously that the drug sulindac, a known non-steroidal anti-inflammatory drug (NSAID) can protect retinal cells and the heart against oxidative damage by initiating a preconditioning response, similar to ischemic preconditioning that is independent of its NSAID activity. The goal of the present studies is to investigate whether sulindac can protect APP-transfected neuronal cells from oxidative damage under hypoxic conditions. METHODS: We established an AD neuronal cell line by overexpressing APP using the plasmid vector pCAX-APP (Swe/Ind) in SHSY5Y neuroblastoma cell line. Cell proliferation was assayed in the AD cell model under hypoxic conditions using trypan blue, under normoxic and hypoxic conditions, with and without sulindac. APP overexpression in the transfected cells was analyzed via Western blot. RESULTS: Our results show that the plasmid DNA induced the expression of APP in transfected SHSY5Y cells compared to untransfected cells and the expression of APP was strongest at 24 h. We observed that the cell proliferation decreased in APP transfected cells in both hypoxic and normoxic conditions. Further, reduced cell proliferation was seen under hypoxic conditions compared to normoxic conditions indicating that hypoxic conditions further exacerbateAD pathology. Our findings in an in vitro AD model, suggest that sulindac has a potential therapeutic value to ameliorate AD pathology. © FASEB.