Mice missing NADH: Ubiquinone Oxidoreductase Fe-S Protein 4 (NDUFS4) are a model of Leigh Syndrome, a mitochondrial disease. NDUFS4 KO mice show reduced lifespan and high levels of acetylation of mitochondrial proteins. The anti-diabetic acarbose increases survival in NDUFS4 knockout mice and reduces mitochondrial protein acetylation, as deduced by reduced acetylation of SOD2 on Lysine 68. SIRT3 is a NAD+/- dependent deacetylase that deacetylates mitochondrial proteins. We sought to determine whether acarbose reduces acetylation in NDUFS4 mice via SIRT3. NDUFS4 and SIRT3 double KO mice were fed acarbose and dissected at 35 days of age. Brain samples were collected and analyzed via western blot. We determined the levels of acetyl K68 SOD2, total SOD2, and actin for each sample. Our results show that acarbose reduces acetylation in knockout NDUFS4 regardless of the presence of SIRT3. Acarbose reshapes the intestinal microbiome and the production of short-chain fatty acids in NDUFS4 KO mice. We are currently devising in vitro experiments to determine whether short-chain fatty acids can reduce mitochondrial protein acetylation in NDUFS4 knockout cells. This research investigates if short-chain fatty acids are responsible for acetylation of mitochondrial proteins. The results can be significant because the acetylation of mitochondrial proteins can prevent diseases from being as deadly by extending lifespan. The work completed during this research is hopeful to be applied to a human model, in which this model can be used to treat mitochondrial diseases.

Lipotoxicity in cells occurs when lipids in biological tissue accrete to a toxic level. This toxic buildup is associated with obesity and type 2 diabetes, two of the leading causes of death around the world. Various studies have induced obesity in mice through a diet consisting of high levels of saturated fats. Some of these studies also investigated the effects Adefovir Dipivoxil, an antiviral and inhibitor of mitochondrial DNA replication, had on these obese mice. My research investigates fibroblasts that have been grown in a high-lipid environment and how Adefovir Dipivoxil affects these cells. We hypothesized that administering Adefovir to these cells would halt apoptosis and prevent further progression of lipotoxicity by stabilizing levels of triacylglycerol synthesis. To test this, I induced lipotoxicity in the cells using palmitic acid, a saturated fatty acid. Next, I treated the cells with Adefovir Dipivoxil. To measure the efficacy of the drug, I used a staining kit to measure the ratio of live to dead cells before and after administering the drug. Furthermore, I used a dye-based assay to measure the intracellular triglyceride levels before and after treatment. In addition to treating fibroblasts with palmitic acid, I treated a new set of fibroblasts with oleic acid, an unsaturated fatty acid, to determine how Adefovir acts on these cells. Data from this research will contribute to further understanding the mechanism of lipotoxicity on various cells, as well as the role that mediators of mitochondrial function like Adefovir Dipivoxil could play in treating lipotoxicity. On a broader scale, we hope that this research will provide insight into future treatments for obesity and type 2 diabetes.