Response of low active GLP-1 like substances to test meal in obese Japanese patients with type 2 diabetes mellitus compared with obese controls with normal glucose tolerance

Abstract

Background: A secretion of plasma active GLP-1 (p-active GLP-1) after ingestion of breakfast test meal (TM) is decreased in obese European patients with type 2 diabetes mellitus (T2DM). However, there was no significant difference in pactive GLP-1 secretion following TM between obese Japanese patients with T2DM and controls. The findings indicate the difference may be due to different races or dietary's customs of subjects. Aims: We examined whether p-active GLP-1 is truly affected by TM in obese Japanese patients (n = 24, group 1) and obese controls (n = 12, group 2). Methods: Glucose (PG), insulin (s-IRI), C-peptide (s-CPR) and active GLP-1 like substances (p-active GLP-1-S) levels in blood were measured 0, 30 and 60 min after TM. Obese Japanese patients with mean 9 years of diabetes had micro-and macro-vascular disturbances and were treated with diet, exercise and/or oral drugs for hyperglycemia. Results: There was no significant difference in sex, age or BMI between groups. Means HbA1c and PG were significantly higher in group 1 than in group 2. There were no significant differences in means of basal s-IRI, HOMA-R and s-CPR between groups. However, means of HOMA-β, insulinogenic index, postprandial s-IRI, s-CPR and p-active GLP-1-S or p-active GLP-1-S/PG values after TM were significantly lower in group 1 than in group 2. Conclusions: These results indicate that a response of p-active GLP-1-S after TM in obese Japanese patients with T2DM was decreased and secretion of GLP-1 relative to PG was impaired. The method of enhancing function of active GLP-1 may be useful for treatment in some of patients with diabetes mellitus.

Effects of Epalrestat as Aldose Reductase Inhibitor (ARI), Sitagliptin as Incretin-Based Therapy (IBT), or Combined Epalrestat and Sitagliptin on Cardiac Vagal Neuropathy (CVN) in Patients with Type 2 Diabetic Mellitus

“…Participants were examined using the same assay methods reported previously [24][25][26][27][28][31][32]. All chemical laboratory data were obtained without fasting.…”

“…Microalbuminuria and macroalbuminuria were defined as UAER ≥30 mg/gCr and ≥300 mg/gCr, respectively [24][25][26][27][28].…”

“…Serum levels of TC, HDL, and LDL were measured by direct methods using commercial kits [24][25][26][27][28]. The normal ranges without fasting in serum were Cr ≤1.0 mg/dL, TC 120-200 mg/dL, HDL 40-90 mg/dL, LDL 80-120 mg/dL and TG 60-300 mg/dL.…”

“…The normal ranges without fasting in serum were Cr ≤1.0 mg/dL, TC 120-200 mg/dL, HDL 40-90 mg/dL, LDL 80-120 mg/dL and TG 60-300 mg/dL. HbA1c (JDS) as an indication of glycemic control was measured by high-performance liquid chromatography [24][25][26][27][28], and the value was expressed as the National Glycohemoglobin Standardization Program (NGSP) equivalent, as per the guidelines of the Japan Diabetes Society [23]. Blood HbA1c (NGSP) less than 6.5% was considered within the normal range.…”

“…As microangiopathy, the presence of retinopathy was examined by an ophthalmologist [24], the presence of nephropathy was ascertained based on albuminuria [25][26][27][28] or renal anemia, and the presence of neuropathy was determined by the neuropathy assessment described below. Macroangiopathy was defined according to past medical history.…”