Quantitative Assessment of Peripheral Oxidative Metabolism With a New Dynamic 1 H MRI Technique: A Pilot Study in People With and Without Diabetes Mellitus

Type 2 diabetes mellitus (T2DM) is linked to impaired mitochondrial function. Chemical exchange saturation transfer (CEST) magnetic resonance imaging (MRI) is a gadolinium-contrast-free H method to assess mitochondrial function by measuring low-concentration metabolites. A CEST MRI-based technique may serve as a non-invasive proxy for assessing mitochondrial health. A H CEST MRI technique may detect significant differences in in vivo skeletal muscle phosphocreatine (SMPCr) kinetics between healthy volunteers and T2DM patients undergoing standardized isometric exercise. Cross-sectional study. Seven subjects without T2DM (T2DM-) and seven age, sex, and BMI-matched subjects with T2DM (T2DM+). Single-shot rapid acquisition with refocusing echoes (RARE) and single-shot gradient-echo sequences, 3 T. Subjects underwent a rest-exercise-recovery imaging protocol to dynamically acquire SMPCr maps in calf musculature. Medial gastrocnemius (MG) and soleus SMPCr concentrations were plotted over time, and SMPCr recovery time, , was determined. Mitochondrial function index was calculated as the ratio of resting SMPCr to . Participants underwent a second exercise protocol for imaging of skeletal muscle blood flow (SMBF), and its association with SMPCr was assessed. Unpaired t-tests and Pearson correlation coefficient. A P value