The influence of early-stage intensive insulin therapy on the plasma levels of vascular en- dothelial growth factor （VEGF） and the related parameters in patients with severe trauma and the clini- cal implication were investigated. Sixty-four cases of severe trauma （injury severity score 〉20） with stress hyperglycemia （blood glucose 〉9 mmol/L） were randomly divided into intensive insulin therapy group and conventional therapy group. ELISA method, radioimmunoassay and density gradient grada- tion one-step process were used to determine plasma VEGF, endothelin-1 （ET-1）, and the number of circulating endothelial cells （CECs） at the day of 0, 2, 3, 5 and 7 after admission. Simultaneously, the changes of CRP concentration in plasma were monitored to evaluate inflammatory response. The results showed that plasma levels of observational indexes in patients receiving early-stage intensive insulin therapy were all significantly lower than those in conventional therapy groups 2, 3, 5 and 7 days after admission [for VEGF （ng/L）, 122.2±23.8 vs. 135.9±26.5, 109.6±27.3 vs. 129.0±18.4, 88.7±18.2 vs. 102.6±27.3, 54.2±26.4 vs. 85.7±35.2, P〈0.05, 0.01, 0.05, 0.05 respectively; for ET-1 （ng/L）, 162.8±23.5 vs. 173.7±13.2, 128.6±17.5 vs. 148.8±22.4, 96.5±14.8 vs. 125.7±14.8, 90.7±16.9 vs. 104.9±22.5, P〈0.05, 0.01, 0.01, 0.01 respectively; for CRP （mg/L）, 23.2±13.8 vs. 31.9±16.5, 13.6±17.3 vs. 23.5±18.4, 8.7±10.2 vs. 15.6±13.3, 5.2±9.4 vs. 10.7±11.2, all P〈0.05; for CECs （/0.9 μL）, 10.9±5.6 vs. 13.9±6.2, 8.5±4.9 vs. 11.3±5.3, 6.3±6.4 vs. 9.4±5.7, 4.8±7.1 vs. 7.8±4.8, all P〈0.05]. It was concluded that intensive insulin therapy could antagonize the endothelium injury after trauma and reduce inflammation response quickly, which was one of important mechanisms by which intensive insulin therapy improves the prognosis of trauma patients.
This study examined the effect of intensive insulin therapy on immune function and inflammatory factors at the early phase after severe trauma. At day 1, 3, 5, 7 after admission, subsets of CD4＋ helper T lymphocytes （Th1/Th2） and human leukocyte antigen （HLA）-DR expression on CD14＋ monocytes were flow cytometrically measured. Levels of cytokines, including tumor necrosis factor-alpha （TNF-α）, interleukin-6 （IL-6）, interleukin-10 （IL-10） and other immunity markers, such as IgA, IgG, IgM, C3, C4 and C reaction protein （CRP） were examined in two groups. The results showed that TNF-α, IL-6 and CRP levels in the intensive insulin therapy group were significantly lower than those in the conventional therapy group, whereas IL-10 levels were substantially increased after intensive insulin therapy. C3 level at day 3, 5, 7 and C4 levels at day 5, 7 were lower in the intensive therapy group than in the conventional therapy group. Th1/Th2 ratios decreased gradually over time in both groups, and were much lower at day 3, 5, 7 in intensive therapy group. There were significant differences among day 3 to day 7 after admission in HLA-DR expression in CD14＋ monocytes. It was concluded that the intensive insulin therapy could decrease pro-inflammatory cytokines and increase anti-inflammatory cytokines in the elderly suffering from severe trauma, at the same time, with complement recovery being delayed. Moreover, intensive insulin therapy promoted immune suppression and, therefore, measures need be taken to address the issue.
