THU312 The Type 1 Diabetes Susceptible LEW.1WR1 Rat Develops Insulin Resistance And Severe Non-alcoholic Fatty Liver Disease

Disclosure: S.T. Love-Rutledge: None. M. Wimalarathne: None. L.D. Mercado: None. A. Smiley: None. C. Apperson: None. Q.C. Vidal: None. A subpopulation of type 1 diabetes patients develop the pathophysiological parameters to be termed double diabetes. This patient population often develops obesity, non-alcoholic fatty liver disease, and other hallmarks of insulin resistance. The LEW.1WR1 rat is a type 1 diabetes susceptible rodent with hyperinsulinemia that has shown signs of fatty liver infiltration(1,2). We hypothesized that LEW.1WR1 rats would develop insulin resistance and severe nonalcoholic fatty liver disease due to its increased circulating insulin and predisposition to autoimmune disease. LEW.1WR1 rats and Wistar Furth rats were used for the 18-week long experiment. Peripheral insulin sensitivity was evaluated using insulin tolerance tests at weeks 11 and 17 showing worsening insulin sensitivity as evidenced by the gradual slope compared to the steep slope of the Wistar Furth rats. HOMA-IR values support LEW.1WR1 rats develop worsening insulin sensitivity and are insulin resistant at week 23 of the experiment (2.613± 0.796, p < 0.0001). Terminal liver mass confirmed increased liver mass normalized to body mass and liver triglyceride levels suggested increased ectopic lid accumulation in the liver (Liver Mass 2.65% ±0.32 p = 0.0005 and triglyceride levels 192.8 ± 21.85 mg/dL, p = 0.034). The H&E-stained digital liver slides were scored for liver ballooning, steatosis, and markers of inflammation. Fibrosis and terminal circulating cytokines were also measured to assess severity of condition. While both groups showed increased steatosis and injury ballooning, trichrome blue staining and inflammatory cytokines verify the severity of disease in the LEW.1WR1 rats. LEW rats have increased fibrosis area and high serum TNF-α, IFN-, MCP-1 levels. As hypothesized, we observed that LEW.1WR1 rats show characteristics of insulin resistance and malignant nonalcoholic fatty liver disease development. References: (1) Wilkerson-Vidal, et al. Mol. Cell. Endocrinol. 2023; 562:111837. (2) Mordes et al, Diabetes. 2005;54(9):2727-2733. Presentation: Thursday, June 15, 2023