Efficacy of short-term intensive treatment with insulin pump to improve islet β-cell function in newly diagnosed type 2 diabetes via inhibition of oxidative stress.

The present study (Chinese Trial Registry GTB7027) assessed the effects of short-term intensive treatment with insulin pump on islet cell function in patients with newly diagnosed type 2 diabetes and the possible mechanism. A total of 100 patients newly diagnosed with type 2 diabetes and hospitalized between January 2016 and December 2017 were divided into a control and an experimental group (n=50 in each group). The subjects of the control group were administered multiple insulin injections for intensive treatment, while the experimental group received short-term intensive treatment with an insulin pump. Analysis of blood parameters, including lipids and glucose, as well as islet β-cell function were performed. The level of reactive oxygen species (ROS) in the peripheral blood mononuclear cells (PBMCs) from the patients was also measured. Oxidative stress indicators, including serum malondialdehyde (MDA) and superoxide dismutase (SOD), were also examined to explore the possible mechanism. The mRNA expression of heme oxygenase 1 (HO-1) and nuclear factor erythroid 2-related factor 2 (Nrf2) in PBMCs were analyzed by reverse transcription-quantitative PCR. The results indicated that the blood lipid levels were significantly improved in the two groups at two weeks, while the experimental group had significantly lower levels of total cholesterol and triglyceride, as well as low- and high-density lipoprotein cholesterol. The function of islet β-cells was significantly improved in the two groups. The insulin secretion index [homeostasis model assessment (HOMA) of β-cell function] in the experimental group was higher, while the insulin resistance (IR) index (HOMA of IR) was significantly lower than that in the control group. The serum MDA level in the experimental group was significantly lower and the SOD level was significantly higher compared with that in the control group. Following treatment, the level of ROS in diabetic PBMCs was significantly reduced, and the transcription level of HO-1 and Nrf2 were also significantly reduced (P<0.05). These results demonstrated that short-term intensive treatment with an insulin pump significantly improved lipid and blood glucose metabolism to protect islet function as well as significantly reducing the level of oxidative stress in patients with newly diagnosed type 2 diabetes.