MON-591 Elevated Glycosuria Triggers Metabolic Stress Response in Renal Glut2 Knockout Mice Through the Activator Protein-1 Family of Transcription Factors Involved in Maintaining Glucose Homeostasis

Abstract Disclosure: N. Rashid: None. P. Lin: None. M. Kaddah: None. T. Cassel: None. A.N. Lane: None. R.M. Higashi: None. N. Hasan: None. M. Hodges: None. K.H. Chhabra: None. Renal Glut2 deficiency, like SGLT2 inhibition, induces massive glycosuria in mice. Yet, their fasting blood glucose levels remain normal without causing hypoglycemia, indicating a compensatory production of endogenous glucose in response to the glycosuria. Deciphering the molecular mechanisms underlying this compensatory increase in glucose production may have implications for increasing the efficiency of SGLT2 inhibitors in treatment of type 2 diabetes. To investigate the mechanism, we performed snRNA sequencing combined with ATAC sequencing on the mouse kidney samples and identified the genes that may contribute to activate the molecular pathways involved in glucose production. To determine changes in energy homeostasis, we analyzed whole body fat mass, lean mass and water content using EchoMRI Body Composition Analyzer. O2 consumption, CO2 production, food intake, water intake and locomotion were also recorded using Sable Promethion System. To explore the fate of glucose among different organs and trace its interconversions to other metabolites, we used 13C6- glucose (oral gavage, 60 mg/mouse) and determined the changes in metabolites in the liver, kidney and skeletal muscle tissues. Metabolites were identified using NMR coupled with ion-chromatography-mass spectrometry. RNA sequencing data revealed an increased expression of genes involved in oxidative phosphorylation and inner mitochondrial membrane proteins whereas transcripts for ribosomal subunits, translational machinery and amino acid metabolism were found to be downregulated in kidneys of Glut2 KO mice. The transcription factors involved in cellular stress response such as the Activator protein-1 family members (JUN, JUNB/D, FOS, FOSL1/2/D) and their mutual regulators CREB5, SMAD2/3, and BATF were enriched in multiple cell types of kidneys in Glut2 KO mice, indicating reprogramming of glucose metabolism through upregulation of glycolysis and enhanced gluconeogenesis. Lean body mass (CON vs KO: 25.43 vs 22.6 ± 0.87 p<0.05) and total body water content (CON vs KO: 21.62 vs 18.82 ±0.84 p<0.05) were lower in Glut2 KO mice as compared to controls. The 13C6-glucose tracer analysis showed a significant increase in isotopologue concentration of metabolites of glycolytic pathway (G-6P, F-6P, F-1,6BP, 1,3-BPG, pyruvate), lactate, TCA cycle (citrate, isocitrate, cis-aconitate, α-ketoglutarate) and mannose pathway (mannose-6P, GDP-mannose) in kidneys of Glut2 KO mice. These metabolic changes are indicative of cellular stress mediated enhanced utilization of glucose through oxidative processes. In summary, our data shows that the transcription factors and metabolic pathways involved in cellular stress response may contribute to the compensatory glucose production observed in renal Glut2 KO mice. Targeting these molecular pathways may help improve the efficiency of SGLT2 inhibitors to treat type 2 diabetes. Presentation: Monday, July 14, 2025