Discipline: Biological Sciences
Subcategory: Cell and Molecular Biology
Elizabeth Quaye - University at Buffalo
Co-Author(s): Donald Sykes, Stanley A. Schwartz, and Supriya D. Mahajan, University at Buffalo, Buffalo, NY
Meth induced damage of the nerve terminals of dopamine-producing neuronal cells triggers activation of apoptotic mechanisms resulting in the complete disintegration and death of neurons, astroglia and microglia. This results in neurotoxicity and neurodegeneration causing significant neuropsychological complications. The exact molecular mechanisms of Meth-induced neurotoxicity remain unclear. Meth mediated apoptosis is accompanied by nuclear damage and differential expression of pro- and antiapoptotic proteins. In the current study, we will examine an array of pro- and antiapoptotic biomarkers that are activated as a consequence of Meth treatment. This will help us identify the specific mechanisms that underlies Meth induced apoptosis. We hypothesized that increasing concentrations of Meth will cause microglial apoptosis which induces mitochondrial dysfunction leading to neurodegeneration. Our goal was to evaluate if Meth treatment induced the activation of the mitochondrion-dependent intrinsic pathway. Gene expression of pro- and antiapoptotic genes were quantitated with QPCR using RNA extracted from cultured microglial cell line (HTHU). Our results indicated that Meth treatment resulted in a significant increase in the gene expression levels of apoptotic proteins like APAF-1, BAX and BCL-2. Analysis of Western Blot data showed a significant modulation of the expression level of the antiapoptotic protein BCL-2 with varying Meth concentrations. Using immunofluorescence analysis we examined the expression of mitochondrial proteins, Cytochrome C, COX 4 and MCL-1, all of which were significantly activated on Meth treatment indicating the activation of the mitochondrion-dependent (intrinsic) apoptotic pathway. We conclude that Meth causes microglial apoptosis via the intrinsic pathway contributing to neurotoxicity and subsequent neurodegeneration.
Funder Acknowledgement(s): The CLIMB UP Summer Research Program, specifically the Institute for the Strategic Enhancement of Educational Diversity.
Faculty Advisor: Supriya Mahajan, email@example.com
Role: The focus of my mentor and her lab members’ research is on the regulation of apoptosis and the various ways in which it is mediated. Some projects look at the role of Galectin-3 in apoptosis as a novel therapeutic target. My project, which was a subset of a larger initiative, looks at the way in which Meth mediates mitochondrial dysfunction or toxicity ultimately leading to the death of the brain’s support cells, the microglia. I was responsible for plating and splitting the cultured HTHU cells as well as Western Blot anaylsis, qPCR, TUNEL staining and an array of other biological assays.