Assessment of predictors of insulin therapy in patients with gestational diabetes diagnosed according to the IADPSG criteria.

AIMS AND INTRODUCTION: It is helpful for both diabetologists and obstetricians to identify patients with gestational diabetes who require insulin therapy for glycemic control during pregnancy. The aim of the present study was to assess potential predictors of insulin requirement in patients with gestational diabetes. MATERIALS AND METHODS: One hundred thirteen patients with gestational diabetes [mean age 34.2 ± 4.5 years; pre-gestational body mass index (BMI), 23.6 ± 6.0 kg/m2] were included in this study. The associations between insulin requirement and the following factors were analyzed: clinical maternal characteristics, number of abnormal oral glucose tolerance test (OGTT) values, gestational age at diagnosis, plasma glucose levels measured during the OGTT, glycated hemoglobin (HbA1c) and glycated albumin levels, and serum C-peptide level before breakfast and 1 and 2 h after breakfast. RESULTS: Thirty-six patients (32 %) required insulin during pregnancy ("insulin group"); the remaining patients were treated with nutrition therapy ("nutrition group"). The insulin group had a higher pre-gestational BMI, higher fasting glucose level, higher area under the curve (AUC) for serum C-peptide level, higher HbA1c level, and a younger gestational age at diagnosis than the nutrition group (p < 0.05, all). Logistic regression analysis showed that the pre-gestational BMI, AUC for serum C-peptide level, and the HbA1c level were independent predictors for the insulin group (p < 0.05, all). CONCLUSIONS: The results suggest that a high insulin resistance and HbA1c level may be associated with insulin requirement in patients with gestational diabetes.

A new mitochondrial pH biosensor for quantitative assessment of pancreatic ß-cell function.

Mitochondrial pH is a key determinant of mitochondrial energy metabolism. We have developed a new fluorescence-based ratiometric pH biosensor using a chloride-insensitive and hydrogen-sensitive probe for direct, quantitative and bleaching-free measurement in a living cell. Fusing this biosensor with a mitochondrial localization signal (MTpHGV) allowed us to determine mitochondrial pH. This new system was applied to measure mitochondrial pH in pancreatic ß-cells, in which mitochondrial function plays a pivotal role in insulin secretion. Rat INS1 cells and mouse MIN6 cells are transfected with MTpHGV stably to monitor mitochondrial pH. While carbonyl cyanide 3-chlorophenylhydrazone (CCCP) treatment rapidly decreased mitochondrial pH in cultured rat MTpHGV-INS-1 cells, MTpHGV-MIN6 cells showed a rapid increase. These data suggest that MTpHGV probe exist in matrix side in INS-1 cells, but on the outer side of mitochondrial inner membrane in MIN6 cells. Moreover, while MTpHGV-INS-1 cells showed a rapid increase of pH by glucose stimulation, mitochondrial pH decreased quickly by glucose stimulation in all MTpHGV-MIN6 cells examined and recovered smoothly. Perfusion study of glucose load in MTpHGV-MIN6 cells under aminooxyacetate (AOA) or 100µM diazoxide showed that this mitochondrial pH acidification was dependent on nicotinamide adenine dinucleotide (NADH) shuttle, but independent from KATP channel. This new system for measuring mitochondrial pH is sensitive across the range of physiologic conditions and may be a useful tool for evaluating mitochondrial function in living cells.

Measurement of HRQL using EQ-5D in patients with type 2 diabetes mellitus in Japan.

OBJECTIVES: We measured the health-related quality of life (HRQL) of diabetes mellitus patients using the Japanese version of EQ-5D, and examined the relationship between clinical condition and health status. METHODS: A study was conducted on 220 patients with type 2 diabetes mellitus at a hospital in Saitama Prefecture on the day of their visit from November 17 to December 24, 1998. Patients evaluated their health status using five dimensions (5D) and a visual analog scale (VAS). The EQ-5D score was calculated based on the 5D responses using the Japanese version of the value set. RESULTS: There were no responses of "extreme problem." The frequency of "some problem" was significantly higher in patients with complications than in those without for mobility (27.4% and 14.4%) and anxiety/depression (25.7% and 13.5%). The mean EQ-5D score was 0.846 (95% confidence interval [CI] 0.817-0.874) in patients with complications versus 0.884 (95% CI 0.855-0.914) in those without complications. There was no statistically significant difference between VAS scores according to the presence or absence of diabetic complications, but a significant difference in VAS scores was seen according to the presence or absence of retinopathy. CONCLUSION: These findings suggest the value of measuring health status in diabetes mellitus patients, because it is able to comprehensively evaluate the patient's health condition, and add another dimension to the subjective symptoms and laboratory data.