Objectives: To explore the effect of transient continuous subcutaneous insulin infusion (CSII) on ß cell function, insulin resistance and vascular endothelial injury in newly diagnosed type 2 diabetic patients and its potential mechanism.
Methods: Ten patients with newly diagnosed type 2 diabetes mellitus (T2DM) accepted CSII for two weeks. Intravenous glucose tolerance test (IVGTT) and hyperinsulinemia euglycemia clamp test were performed before and after CSII. Serum soluble E-selectin (sE-selectin) was used to evaluate the injury of vascular endothelial cell, while serum high sensitivity C reactive protein (hsCRP) and soluble CD₁₄ (sCD₁₄) were both used to assess inflammatory condition.
Results: (1) Compared with those before treatment, the blood glucose levels of IVGTT, the area under the curve of the blood glucose, glycosylated hemoglobin, TC and LDL-C in the patients were decreased after CSII (P < 0.05 or 0.01). (2) Compared with those before treatment, the insulin levels of IVGTT (except the fasting insulin), the area under the curve of insulin and acute insulin response were all increased after CSII (P < 0.05 or 0.01). (3) Compared with that before treatment, the glucose infusion ratio in the clamp test [(3.46 ± 1.66) mg x kg⁻¹ x min⁻¹ increased to (7.14 ± 2.37) mg x kg⁻¹ x min⁻¹] and HOMA-beta elevated, while HOMA-IR declined (P < 0.05 or 0.01 in all). (4) Compared with those before treatment, the levels of serum sE-selectin, sCD₁₄ and hsCRP were decreased (P < 0.01, except for hsCRP).
Conclusion: Transient intensive insulin therapy in patients with newly diagnosed T2DM is useful to restore beta cell function, attenuate insulin resistance, repair vascular endothelial injury and improve the disorder of blood sugar and lipid. The mechanism may be related with the inhibition of inflammation in patients.