Long-term assessment of glucose tolerance and targeted metabolomics analysis in mice with burn injury

Background  Burn patients have a higher risk of diabetes in terms of prognosis compared to healthy people. Previous studies have focused on short-term changes in blood sugar and immune function in patients. The long-term changes of glucose metabolism in burned mice were investigated in order to provide a new direction for clinical research.

Objective To observe the long-term blood glucose regulation and spleen T-cell targeted metabolism level of burned mice, and provide references for exploring the metabolic mechanism of long-term hypoimmunity in burn patients.

Methods Male Balb/c mice were randomly divided into sham group and burn group with 40 mice in each group, and 5 healthy Balb/c mice were selected as control group. A total body surface area (TBSA) burn model of 15% of the total body surface area was established in both the sham group and the burn group. Blood glucose and plasma insulin levels, as well as glucose tolerance and insulin sensitivity in each group of mice were compared after 3 months. In addition, sham and burn models were prepared. After 24 days, CD3 ⁺ T cells of spleen were sorted by magnetic beads, and T cells targeted metabolites were detected by high pressure liquid chromatography combined with mass spectrometer.

Results Targeted metabolomics analysis of spleen T cells of mice at 24 days after burn showed no significant difference in the charge energy of fructose 1, 6-diphosphate, phosphoenolpyruvate, pyruvate, succinic acid, lactic acid and adenylate in the glycolytic pathway in the burn group compared with the control group and the sham injury group (P > 0.05). However, the intermediate products of the tricarboxylic acid cycle, cisaconite and isocitric acid, were decreased (P < 0.05). At three months after burn, the blood glucose level of burn group was higher than that of sham injury group (P=0.022), but there was no significant difference in plasma insulin level between burn group and sham injury group (P=0.173). The effect of burn model on blood glucose in the burn group was higher than that in the sham injury group in the glucose tolerance test (P < 0.001), but there was no difference between the two groups in the insulin sensitivity test (P=0.683).

Conclusion Burned mice have long-term abnormal blood glucose regulation and T cell glucose metabolism defects.