The Effect of Early Intensive Insulin Therapy on Body Fat Distribution andβ-Cell Function in Newly Diagnosed Type 2 Diabetes

Abstract

Objectives. The aim of this study was to evaluate the effects of early intensive insulin therapy on body fat distribution, lean body mass and β-cell function in patients with newly diagnosed type 2 diabetes. Methods. Thirty-eight subjects with newly diagnosed type 2 diabetes participated in a 12-week course of intensive insulin therapy. Patients were administered a 75 g oral glucose tolerance test (OGTT), underwent measurement of visceral and subcutaneous adipose tissues (VAT and SAT) using computed tomography and appendicular skeletal muscle (ASM) mass was assessed using dual-energy X-ray absorptiometry. Results. After intensive insulin therapy, fasting plasma glucose and HbA1c levels decreased. Homeostasis model assessment (HOMA)-B, the insulinogenic index, and the C-peptide-to-glucose area under the curve (AUC) ratio increased. The insulin sensitivity index and the glucose AUC decreased after 12 weeks. The body composition analysis revealed that the VAT and the ratio of VAT to SAT decreased, whereas body weight and total fat mass increased nonsignificantly. The ASM/weight and skeletal muscle mass index increased. The restoration of β-cell function, as identified by HOMA-B, the insulinogenic index, and the C-peptide-to-glucose AUC ratio, was correlated with the changes in VAT when controlled for age and gender. In multiple regression analyses, the decrease in VAT was shown to independently contribute to improved HbA1c over the study period, after adjusting for confounding factors. Conclusions. These results suggest that a shift in fat distribution from visceral to subcutaneous fat after early intensive insulin therapy is associated with improvements in glycemic control and β-cell function in patients with newly diagnosed type 2 diabetes.

Effects of insulin therapy on weight gain and fat distribution in the HF/HS-STZ rat model of type 2 diabetes

“…In accordance with our data, increased levels of lean body mass have been shown after insulin therapy in type 2 diabetes subjects. 31,32 Our observation that insulin therapy resulted in elevated levels of SAT in HF/HS-STZ rats also agrees with data from some human studies. 32,33 However, three other clinical studies observed no change in SAT after insulin therapy.…”

“…31,32 Our observation that insulin therapy resulted in elevated levels of SAT in HF/HS-STZ rats also agrees with data from some human studies. 32,33 However, three other clinical studies observed no change in SAT after insulin therapy. 10,31,34 We observed an insulin-induced increase in VAT, which likewise has been reported in human studies.…”

Diet Is Critical for Prolonged Glycemic Control after Short-Term Insulin Treatment in High-Fat Diet-Induced Type 2 Diabetic Male Mice

“…It is believed that EIT improves multiple adverse metabolic consequences by rapidly overcoming “glucolipotoxicity” in β-cells and other insulin target cells; especially liver and muscle, thereby reducing endogenous insulin requirements, facilitating “β-cell rest”, protecting β-cell function, and by improving insulin sensitivity [ 6 , 7 ]. Insulin also possesses anti-inflammatory and antioxidant properties that may help protect against endothelial dysfunction and vascular complications [ 8 – 11 ], positively altering the course of vascular disease progression.…”

Short‐term intensive insulin therapy at diagnosis in type 2 diabetes: plan for filling the gaps

“…One study has suggested that decreases in tumour necrosis factor‐alpha may contribute to the positive effect of STII therapy on beta‐cells . Another study has provided evidence that decreased visceral fat and increased skeletal muscle mass following insulin treatment may be associated with the observed improvements in function . The liver is central to the pathogenesis of type 2 diabetes, with hepatic glucose production being tightly regulated by portal‐insulin concentration .…”