Decrement of postprandial insulin secretion determines the progressive nature of type-2 diabetes

Abstract

Objective: Type-2 diabetes is a progressive disease. However, little is known about whether decreased fasting or postprandial pancreatic b-cell responsiveness is more prominent with increased duration of diabetes. The aim of this study was to evaluate the relationship between insulin secretion both during fasting and 2 h postprandial, and the duration of diabetes in type-2 diabetic patients. Design: Cross-sectional clinical investigation. Methods: We conducted a meal tolerance test in 1466 type-2 diabetic patients and calculated fasting (M 0 ) and postprandial (M 1 ) b-cell responsiveness. Results: The fasting C-peptide, postprandial C-peptide, M 0 , and M 1 values were lower, but HbA 1c values were higher, in patients with diabetes duration O 10 years than those in other groups. There was no difference in the HbA 1c levels according to the tertiles of their fasting C-peptide level. However, in a group of patients with highest postprandial C-peptide tertile, the HbA 1c values were significantly lower than those in other groups. After adjustment of age, sex, and body mass index (BMI), the duration of diabetes was found to be negatively correlated with fasting C-peptide (gZK0.102), postprandial Cpeptide (gZK0.356), M 0 (gZK0.263), and M 1 (gZK0.315; P!0.01 respectively). After adjustment of age, sex, and BMI, HbA 1c was found to be negatively correlated with postprandial Cpeptide (gZK0.264), M 0 (gZK0.379), and M 1 (gZK0.522), however, positively correlated with fasting C-peptide (gZ0.105; P!0.01 respectively). In stepwise multiple regression analysis, M 0 , M 1 , and homeostasis model assessment for insulin resistance (HOMA-IR) emerged as predictors of HbA lc after adjustment for age, sex, and BMI (R 2 Z0.272, 0.080, and 0.056 respectively). Conclusions: With increasing duration of diabetes, the decrease of postprandial insulin secretion is becoming more prominent, and postprandial b-cell responsiveness may be a more important determinant for glycemic control than fasting b-cell responsiveness.European Journal of Endocrinology 155 615-622

Adiponectin Downregulates Hyperglycemia and Reduces Pancreatic Islet Apoptosis After Roux-En-Y Gastric Bypass Surgery

“…Our data indicated the response of insulin to plasma glucose weakened and insulin resistance occurred in T2DM, which accorded with previous investigations [20]. The postprandial insulin concentration was significantly increased in RYGB group postoperatively, which indicated that the maximal secretory capacity of the beta cell was improved.…”

Metabolic follow-up after long-term pancreas graft survival

“…Thus, a reduced b-cell function could explain differences in glucose metabolism in the cross-sectional analysis but not in the prospective studies. In type 2 diabetes, a decrement of especially the postprandial insulin secretion determines the progressive nature of the disease (23,24). A progressive reduction in insulin secretion was not found in grafted patients, at least not in those with long-term survival.…”

Predictive factors for the efficacy of switch to oral hypoglycemic agents in Japanese type 2 diabetic patients with intensive insulin therapy temporarily introduced

“…Several studies reported that obesity resulted in an increase in β cell mass and insulin secretion [28,29]. It was also reported that insulin secretion decreased over time in type 2 diabetes, and that diabetic duration was negatively correlated with insulin secretion [26,27]. It would be no surprise that these factors which would reflect insulin secretion were associated with the efficacy of OHA in the current study population.…”

“…It has been reported that some clinical characteristics, such as age, diabetic duration, and BMI are associated with insulin secretion in insulin-naïve patients [22][23][24][25][26][27][28][29]. However it was unclear whether these factors were also useful to predict the efficacy of OHA after the temporary introduction of intensive insulin therapy.…”