7936 Type 1 Diabetes Therapeutic Compound MSB-61: Using RNA Sequencing To Identify The Mechanism

Abstract

Abstract Disclosure: P. Khan: None. K. Corbin: None. N. Ajmal: None. S. Bergmeir: None. G. Gu: None. X. Tong: None. C.S. Nunemaker: None. Abstract Type 1 diabetes (T1D) is a chronic autoimmune disease in which loss of insulin-producing beta-cells leads to hyperglycemia due to which patients eventually require lifelong insulin therapy to maintain normal glycemic control. Insulin remains the gold standard and the only effective treatment for T1D since its discovery 100 years ago. Protecting the pancreatic beta cells from cytokine-induced cell death and restoring insulin secretion are important to treat T1D, two properties that are currently lacking in present therapies. Our lab identified a chemical compound MSB-61 that increases insulin release and protects pancreatic islets against T1D-associated cytokines and endoplasmic reticulum (ER) stress. This study aims to identify the mechanism of action of MSB-61 in protecting pancreatic islets from ER stress-induced cell death. To achieve this aim pancreatic islets obtained from CD-1 strain mice were exposed for one hour to 50uM MSB-61 or vehicle control. After treatment, RNA was collected for RNA sequencing. In addition to RNA extraction for sequencing, MSB-61's ability to secrete insulin was verified by performing ELISA on control,10 and 50uM MSB-61-treated islets, and the activity of protection from cell death was assessed by performing cell death assay on islets treated with ER stressors in the presence and absence of 10 and 50uM MSB-61. Using Genialis, a bioinformatics service, we evaluated 57,010 genes (including non-coding transcripts) in our RNA sequencing data set. The DESeq2 technique of data analysis allowed us to identify 350 differentially expressed genes (DEGs), of which 251 were upregulated and 74 were downregulated. After removing non-coding/undefined transcripts and genes with <5 counts per million, a total of 117 genes remained; 108 up and 9 down. According to the String database (string-db.org), many of the top DEGs formed a common network of genes associated with cell death protection and insulin secretion. A key component of that gene network is a stress-responsive orphan nuclear receptor with known protective effects in beta cells. Testing this orphan nuclear receptor as a possible direct or indirect target of MSB-61 for cell death prevention can aid in identifying the genes and pathways targeted by MSB-61, allowing us to improve our approaches to T1D treatment and develop better medications. Presentation: 6/3/2024