SAT-044 Diabetes Alters Ischemia-Induced Gene Expression

Abstract: Peripheral Arterial Disease (PAD) is the result of atherosclerosis that impairs blood flow to the lower extremities and constitutes a major complication of diabetes. Individuals with Diabetes are more likely to develop PAD and when they have PAD, they have poorer outcomes. We hypothesized that Diabetes may alter normal adaptive gene expression in PAD. Type 2 diabetic (T2D) mice were generated by placing C57Bl/6 mice on a high-fat diet (HFD) starting at 6 weeks. 14-16-week-old HFD fed C57BL/6 (B6) mice were used. Experimental PAD was achieved by unilateral femoral artery ligation and excision. Controls were strain, age, and sex-matched. Total RNA was extracted from the ischemic gastrocnemius muscle on day 3 post-op. RNA was processed and hybridized onto Affymetrix Mouse430 expression arrays according to the manufacturer’s protocols. Expression values were normalized and provided expression analysis data on a total of 45,101 probe sets. We identified 1261 probe set with highly significant expression differences between controls and experimental mice (p < 0.005, no multiple test correction). 496 had lower expression in T2D compared to non-diabetic mice, while 765 genes had higher expression in T2D. To better understand the molecular pathways and biological processes associated with the genes altered in T2D we performed the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses on the top 500 differentially expressed genes. Our analysis identified important biologic pathways such as “metabolic pathways”, “phagosomes”, “lysosomes” and “regulation of actin cytoskeleton”. In addition to KEGG pathways, we performed Gene ontology analyses (p < 0.005, no multiple test correction) to better categorize genes found to be differentially expressed between non-diabetic and T2D mice. Gene ontology categories most strongly represented are “cellular processes”, “metabolic processes,” localization and “binding”. Our results confirmed that T2D alters post ischemic gene expression and advanced our knowledge about the specific genes and pathways that may modulate PAD severity and outcomes in T2D. Source of Research Support: Robert Wood Johnson Foundation, AMFDP Grant.