Lipid metabolism after mild cold stress in persons with a cervical spinal cord injury

Study design: Experimental study. Objectives: To compare lipid metabolism in individuals with a cervical spinal cord injury (SCI_C) and able-bodied (AB) persons in response to mild cold stress.Settings: Laboratory of Wakayama Medical University, Japan. Methods: Nine males with SCI_C and 11 AB wore a water-perfusion suit in a supine position. Following 30-min rest thermoneutrality, the whole body was cooled by perfusing 25°C water through the suit for 15-20 minutes (CS). Blood samples were collected before, immediately, and 60 (post-CS60) and 120 minutes after CS (post-CS120). Concentrations of serum free fatty acid ([FFA]s), total ketone bodies ([tKB]s), insulin ([Ins]s) and plasma adrenaline ([Ad]p), noradrenaline ([NA]p) and glucose ([Glc]p) were assessed. Results: [Ad]p in SCIC were lower than AB throughout the study (p=0.0002) and remained largely unchanged in both groups. [NA]p increased after cold stress in AB only (p<0.0001; GxT p=0.006). [FFA]s increased by 62% immediately after cold stress in SCI_C (p=0.0028), without a difference between groups (p=0.65). [tKB]s increased by 69% at post-CS60 and 132% at post-CS120 from the start in SCIC with no differences between groups (p=0.54). [Glc]p and [Ins]s were reduced in SCIc only (GxT p=0.003 and p=0.001, respectively). Conclusion: These data indicate that mild cold stress acutely elevates lipid and ketone body metabolism in persons with SCIc, despite the presence of sympathetic dysfunction.