RT Journal Article SR Electronic T1 Relative Hypoxia and Early Diabetic Kidney Disease in Type 1 Diabetes. JF Diabetes JO Diabetes FD American Diabetes Association SP db200457 DO 10.2337/db20-0457 A1 Vinovskis, Carissa A1 Li, Lu-Ping A1 Prasad, Pottumarthi A1 Tommerdahl, Kalie A1 Pyle, Laura A1 Nelson, Robert G. A1 Pavkov, Meda E. A1 van Raalte, Daniel A1 Rewers, Marian A1 Pragnell, Marlon A1 Mahmud, Farid H. A1 Cherney, David Z. A1 Johnson, Richard J. A1 Nadeau, Kristen J. A1 Bjornstad, Petter YR 2020 UL http://diabetes.diabetesjournals.org/content/early/2020/07/30/db20-0457.abstract AB The objective of this study was to compare the ratio of renal oxygen availability (RO2) to GFR (RO2:GFR), a measure of relative renal hypoxia, in adolescents with and without type 1 diabetes (T1D) and relate the ratio to albuminuria, renal plasma flow (RPF), fat mass, and insulin sensitivity (M/I). RO2 was estimated by blood oxygenation level dependent (BOLD) MRI, fat mass by DXA, GFR and RPF by iohexol and p-aminohippurate clearance, albuminuria by urine albumin-to-creatinine ratio (UACR), and M/I from steady-state glucose infusion rate/insulin (mg/kg/min) by hyperglycemic clamp in 50 adolescents with T1D (16.1±3.0 years, HbA1c 8.6±1.2%) and 20 controls of similar BMI (16.1±2.9 years, HbA1c 5.2±0.2%). The RO2:GFR (ms/ml/min) was calculated as renal oxygen availability (T2*, ms) divided by GFR (ml/min). Whole-kidney RO2:GFR was 25% lower in adolescents with T1D vs. controls (p<0.0001). In adolescents with T1D, lower whole-kidney RO2:GFR associated with higher UACR (r=-0.31, p=0.03), RPF (r=-0.52, p=0.0009) and fat mass (r=-0.33, p=0.02). Lower medullary RO2:GFR associated with lower M/I (r=0.31, p=0.03). In conclusion, adolescents with T1D exhibited relative renal hypoxia that associated with albuminuria, increased RPF, fat mass, and insulin resistance. These data suggest a potential role of renal hypoxia in the development of DKD.