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Introduction Reduced muscle strength is a high risk factor for type 2 diabetes mellitus, and this association is especially strong in non-obese male individuals. However, it remains unclear how reduced muscle strength affects susceptibility to diabetes. We have examined whether lower limb muscle strength is associated with insulin resistance in non-obese Japanese male subjects. Methods Measurements from 64 non-diabetic, non-obese, middle-aged Japanese men were analyzed. Insulin sensitivity in muscle was measured using the hyperinsulinemic-euglycemic clamp. Isometric muscle strength of the knee extensor and flexor muscles was evaluated using a dynameter. Results Lower muscle strength of knee flexors, but not knee extensors, was associated with impaired muscle insulin sensitivity (knee flexor muscles: low, medium, and high strength was 6.6 ± 2.2, 7.3 ± 2.0, and 8.8 ± 2.2 mg/kg per minute, respectively, p for trend

Accumulation of intramyocellular lipid (IMCL) is observed in individuals with insulin resistance as well as insulin-sensitive endurance athletes with high peak oxygen consumption (VO

In 169 Japanese patients with type 2 diabetes mellitus with blood glucose levels that were inadequately controlled with diet and exercise therapy alone, or with diet and exercise therapy plus a sulfonylurea (SU) drug, we evaluated the safety and efficacy of global standard dose metformin given up to a maximum daily dose of 2250 mg for 54 weeks. The changes in HbA1c from baseline to the final evaluation visit were -1.32 ± 0.76% for metformin monotherapy and -1.29 ± 0.81% for metformin plus SU, both significantly lower than baseline. The incidences of adverse events and adverse drug reactions were 91.1% (154/169 patients) and 67.5% (114/169 patients), respectively. The most common adverse events were gastrointestinal symptoms, and most of the gastrointestinal symptoms were considered by investigators to be related to metformin treatment. An increased blood lactic acid level was observed in three subjects (1.8%); however, no clinical symptoms were reported, and there was no increase in mean lactic acid concentration throughout the evaluation period. Symptoms of hypoglycemia were reported in 16 patients, all receiving metformin plus SU, but none received metformin monotherapy. There was a decrease in mean body weight. Global standard dose metformin may be useful for maintaining good blood glucose control over the long term in the treatment of type 2 diabetes mellitus in Japanese patients.

Metabolic clearance rate of insulin (MCRI) is thought to help maintain glucose homeostasis even in healthy subjects. However, the effect of a low carbohydrate/high fat (LCHF) diet on MCRI in healthy subject remains unclear. To investigate the effect of a 3-day eucaloric LCHF diet on MCRI in healthy subjects, we studied 42 healthy non-obese Japanese men. Each subject consumed a eucaloric LCHF diet for 3 days. Before and after the LCHF diet, intramyocellular lipid (IMCL) levels were measured using 1H-magnetic resonance spectroscopy, and glucose infusion rate (GIR) and MCRI were evaluated with a euglycemic hyperinsulinemic clamp. The LCHF diet increased MCRI by 10% and decreased steady state serum insulin (SSSI) and GIR during glucose clamp by 10% and 6%, respectively. To further investigate the role of MCRI, we divided subjects into high-responder (HR) and low-responder (LR) groups based on the median %change in MCRI. The LCHF diet increased IMCL and decreased SSSI during glucose clamp in the HR group, while those were not altered in the LR group. Our results suggested that a 3-day eucaloric LCHF diet increases MCRI in healthy non-obese Japanese men. This change seemed to be beneficial in terms of maintaining euglycemia during low carbohydrate availability.

Aims To evaluate the association of rs7578597 in THADA, rs10886471 in GRK5, rs7403531 in RASGRP1, and rs6723108 in TMEM163 with type 2 diabetes among the Japanese we performed a replication study of the association of these single nucleotide polymorphism (SNP) loci.

Purpose This study was performed to investigate important factors of exercise therapies for diabetes patients in Japan.

Hypertension is associated with substantial morbidity in Japan. The aim of this work was to evaluate whether hypertension is associated with white matter microstructural changes by using diffusional kurtosis imaging (DKI). We explored the regional patterns of white matter alteration in 15 hypertensive middle-aged male participants and 11 normotensive controls by using DKI-based whole-brain analysis. In addition, we investigated whether the observed white matter microstructural changes were related to systolic or diastolic blood pressure by using Pearson’s correlation coefficient analysis. Mean diffusional kurtosis (MDK) values were significantly higher in hypertensive participants than in normotensive participants (P

Objective Quality of life (QOL) is recognized as an important medical outcome. The aim of this study was to test the validity and reliability of the Japanese version of the Diabetes Quality-Of-Life (J-DQOL) questionnaire originally developed by the Diabetes Control and Complications Trial.

Overall adiposity is associated with insulin resistance. Decline in insulin sensitivity induces a compensatory increase in insulin secretion from beta cells. The impact of adipose tissue distribution, i.e., visceral versus subcutaneous fat, on beta cell function remains to be elucidated. The aim of this study was to retrospectively investigate the relation between the areas of subcutaneous and visceral fat and the increment in C-peptide levels (CPR) during glucagon load (ΔCPR) in Japanese patients with type 2 diabetes. In 195 Japanese patients with type 2 diabetes, beta cell function was evaluated by ΔCPR, CPR index (100 × fasting CPR divided by fasting glucose), and 24-h urinary C-peptide excretion (U-CPR) during the 1-week hospitalization for diabetes education. Then, we investigated the relationships between markers of beta cell function and the areas of visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) determined by abdominal computed tomography. Stepwise multiple regression analyses identified SAT, but not VAT, as an independent variable of both ΔCPR and U-CPR [standard regression coefficient (Stdβ) = 0.332, P < 0.01 for ΔCPR, and Stdβ = 0.181, P < 0.05 for U-CPR], and both SAT and VAT were identified as independent variables for CPR index (Stdβ = 0.253, P < 0.01 for SAT, and Stdβ = 0.193, P < 0.01 for VAT). Our results indicated that SAT is independently correlated with beta cell function by glucagon test in Japanese patients with type 2 diabetes.

We investigated the clinical factors that affected routine laboratory tests of C-peptide levels (CPR) used for the evaluation of β-cell function in Japanese patients with type 2 diabetes. The study subjects were 215 Japanese patients with type 2 diabetes admitted to Juntendo University Hospital just for glycemic control. β-cell function was evaluated by ΔCPR (6-min postglucagon increment in CPR), CPR index (100 × fasting CPR divided by fasting glucose), and 24-h urinary CPR excretion (U-CPR). Stepwise multiple regression analyses of relationships between clinical parameters and these laboratory tests were carried out. The analysis identified BMI and treatment with insulin before admission, but not glycosylated hemoglobin at admission, as independent determinants of all β-cell function tests [BMI: Stdβ (standard regression coefficient) = 0.337, P < 0.01 for ΔCPR, Stdβ = 0.365, P < 0.01 for CPR index, and Stdβ = 0.207, P < 0.01 for U-CPR, and treatment with insulin before admission: Stdβ = −0.141, P = 0.023 for ΔCPR, Stdβ = −0.285, P < 0.01 for CPR index, and Stdβ = −0.258, P < 0.01 for U-CPR]. The estimated glomerular filtration rate (eGFR) was an independent determinant of U-CPR (Stdβ = 0.145, P = 0.023), but not ΔCPR. In conclusion, ΔCPR evaluates β-cell function without being affected by eGFR and glycemic control over the preceding 2–3 months.

In a phase III study, voglibose was shown to reduce the risk of development of type 2 diabetes mellitus (T2DM) by 40.5 % in Japanese individuals with impaired glucose tolerance (IGT), and appeared to promote reversion of IGT to normal glucose tolerance (NGT). In a retrospective, post hoc analysis, data from this study, plus follow-up findings from subjects who achieved NGT during the study and who were off-treatment, were analyzed to investigate serum insulin kinetic parameters which might be predictors of IGT reversion to NGT, and maintenance of NGT once achieved. The effects of voglibose on serum insulin kinetics in individuals with IGT were also assessed. Subjects with IGT (n = 1778) were randomized to receive voglibose (0.6 mg/day) or placebo for a mean of 48.1 weeks. During treatment, 1053 subjects achieved NGT, 569 continued to have IGT, and 156 developed T2DM. Analysis of baseline characteristics in each outcome group showed that subjects with higher 30-min serum immunoreactive insulin (IRI) levels in a 75 g oral glucose tolerance test (OGTT) or higher insulinogenic indexes at baseline were more likely to achieve NGT, whether they received voglibose or placebo. Among subjects who achieved NGT, the mean increase in OGTT 30-min IRI level from baseline to endpoint was significantly greater after treatment with voglibose than with placebo. Individuals who had higher OGTT 30-min IRI levels when achieving NGT seemed more likely to sustain this state. Thus, insulin secretion kinetics appeared to predict reversion of IGT to NGT and maintenance of NGT once achieved.

Biphasic insulin aspart 30 (BIAsp 30) includes 30% soluble rapid-acting insulin aspart (IAsp) along with an intermediate-acting 70% protaminated IAsp that provides coverage of prandial and basal insulin in a single injection. As BIAsp 30 has been available internationally for 10 years, this review provides a comprehensive overview of the discovery of BIAsp 30, its pharmacokinetic and pharmacodynamic profile, safety and efficacy outcomes from the clinical trial programme, 'real-life' clinical insights provided by observational study data, and cost effectiveness and quality-of-life information. These studies have demonstrated that BIAsp 30 once or twice daily is an appropriate option for insulin initiation. BIAsp 30 also provides a switch option in patients on biphasic human insulin (BHI). Switching from BHI to BIAsp 30 is associated with improved postprandial glucose (PPG) and reduced nocturnal and major hypoglycaemia, although daytime hypoglycaemia is higher with BIAsp 30. Intensification of BIAsp 30 can be achieved by increasing the number of daily doses up to three times daily with meals. Therefore, BIAsp 30 provides an intensification option for individuals who are not achieving control with basal insulin and would prefer the simplicity of a single biphasic insulin instead of progressing to a basal-bolus approach. BIAsp 30 has a simple dose-titration algorithm, which enables patients to effectively self-titrate their insulin dose. Cost-effectiveness analyses have demonstrated that BIAsp 30 is cost effective or dominant compared with BHI 30 or insulin glargine in a number of healthcare settings. In conclusion, BIAsp 30 offers a simple and flexible option for insulin initiation and intensification that provides coverage of both fasting and prandial glucose.

Purpose This study was performed to investigate the actual situation and problems of exercise therapy in Japan.

Several epidemiological studies have shown that more than 20% of the general adult population has symptoms of insomnia, but only about 5% of them are receiving treatment for the symptoms. Most general physicians and patients seem to be unaware of both the potential morbidity associated with insomnia and the importance of sleep health. In addition, most people having sleep problems do not tell their primary physicians about the problems, while about 70% of physicians do not ask their patients about the existence of sleep problems. Sleep disorders have been reported to underlie the development and deterioration of several comorbid diseases such as hypertension, cardiovascular diseases, diabetes and depression. Thus, we performed a systematic review of the relationship between insomnia and comorbid disorders to provide recent knowledge on this and to facilitate insomnia treatment to prevent the development of these comorbid disorders. In addition, we briefly introduce the Japanese consensus report on the management of insomnia in general practice that was established in 2010. We expect that this review paper will contribute to the advancement of the management of insomnia in general practice.

The onset and progression of type 2 diabetes largely depends on pancreatic β-cell failure in the setting of insulin resistance. In most type 2 diabetic patients, loss of β-cell function and mass is associated with worsening of glycemic control. In this regard, type 2 diabetes could be regarded as a disease of pancreatic β-cell failure. This concept was further supported by the results of recent genome-wide association studies that identified genes that potentially regulate β-cell function and growth as type 2 diabetes susceptibility loci. The response of normal β cells to increased insulin demands includes both enhanced insulin secretion per cell and expansion of β-cell mass. Whereas the precise molecular mechanism underlying the compensatory response of β cells is unknown, recent studies using autophagy-deficient animal models have highlighted the importance of autophagy in the preservation of normal islet architecture and enhancement of β-cell function, especially under insulin-resistant states. Furthermore, normal autophagy function has been shown to play important roles in maintaining hepatic insulin sensitivity by counteracting endoplasmic reticulum stress. In this article, we review knowledge of the role of autophagy in maintaining β-cell function, hepatic insulin sensitivity, and its possible implication in diabetes pathogenesis. Identifying autophagy as a critical modulator of the two major pathological arms of type 2 diabetes—impaired insulin secretion and insulin sensitivity—may direct the development of future therapeutic strategies for this disease.

The aim of our study was to investigate clinical factors associated with the development of chronic kidney disease (CKD) in Japanese type 2 diabetes patients diagnosed by the new equation established by the Japanese Society of Nephrology. We analyzed data collected from 653 Japanese patients with type 2 diabetes who were followed at Juntendo University Hospital for 2 years to determine the risk factors for new-onset CKD and 2-year eGFR decline from the baseline. CKD developed de novo in 56 diabetic patients, whereas 288 patients showed no signs of CKD at the end of the 2-year follow-up period. The 2-year cumulative incidence of newly diagnosed cases with CKD was 8.6%. Of these, the transition rate to albuminuria was 73.2%, the proportion of patients who developed low eGFR (

Recent studies have suggested that treatment of type 2 diabetes soon after diagnosis of diabetes correlates with a long-term reduction in the risk of macroangiopathy. An open-label prospective crossover trial was performed to compare the efficacy and adverse effects of low-dose nateglinide with those of acarbose. The subjects were 23 early type 2 Japanese diabetic patients who were oral hypoglycemic agent naive and whose HbA1C levels were 6.0–6.9%. Twelve patients received 90 mg/day of nateglinide and 11 patients received 150 mg/day of acarbose. After 12 weeks of either therapy, the drugs were switched and treatment was continued for another 12 weeks. Each patient was requested to complete a questionnaire on complications after the completion of each treatment. HbA1C decreased from a mean baseline of 6.7 ± 0.2 to 6.4 ± 0.3% with nateglinide and to 6.5 ± 0.3% with acarbose. Decreases of HbA1C in nateglinide were larger than those in acarbose, albeit statistically insignificant (p = 0.073). Symptoms related to hypoglycemia were scarcely observed with either treatment. Abdominal fullness/borborygmi were frequently reported by patients on acarbose but were absent or mild in those on nateglinide. After the completion of the study, most patients favored nateglinide over acarbose. Our results suggest that the effects of low-dose nateglinide on postprandial hyperglycemia of early type 2 diabetes are equivalent to those of acarbose, with the added advantage of minimal side effects.

We conducted a genome-wide association study of type 2 diabetes (T2D) using 459,359 SNPs in a Japanese population with a three-stage study design (stage 1, 4,470 cases and 3,071 controls; stage 2, 2,886 cases and 3,087 controls; stage 3, 3,622 cases and 2,356 controls). We identified new associations in UBE2E2 on chromosome 3 and in C2CD4A-C2CD4B on chromosome 15 at genome-wide significant levels (rs7612463 in UBE2E2, combined P = 2.27 × 10⁻⁹; rs7172432 in C2CD4A-C2CD4B, combined P = 3.66 × 10⁻⁹). The association of these two loci with T2D was replicated in other east Asian populations. In the European populations, the C2CD4A-C2CD4B locus was significantly associated with T2D, and a combined analysis of all populations gave P = 8.78 × 10⁻¹⁴, whereas the UBE2E2 locus did not show association to T2D. In conclusion, we identified two new loci at UBE2E2 and C2CD4A-C2CD4B associated with susceptibility to T2D.

Combination therapy with an α-glucosidase inhibitor and insulin is commonly performed for type 2 diabetes mellitus. We conducted a placebo-controlled double-blind comparative study to investigate the efficacy of combination therapy with miglitol and insulin. The patients with T2DM on insulin therapy were randomly assigned to either a miglitol treatment group (Group M) or a placebo group (Group P) and treated for 12 weeks. Meal tolerance tests were conducted at the observation period, week 0 and week 12 of the treatment period. Mean values of decrease in 1-h- and 2-h postprandial plasma glucose level were significantly larger in Group M than in Group P (60.3 ± 70.1 mg/dl vs. −5.1 ± 68.2 mg/dl (P

Additional susceptibility loci for type 2 diabetes have been identified by a meta-analysis of genome-wide association studies (GWASs) in European populations. To examine further the roles of these new loci, we performed a replication study for the association of these single-nucleotide polymorphism (SNP) loci with the disease in three independent Japanese populations.We genotyped seven of the 11 SNPs that emerged in stage 2 of the meta-analysis for European GWASs (rs864745 in JAZF1, rs12779790 near CDC123/CAMK1D, rs7961581 near TSPAN8/LGR5, rs4607103 near ADAMTS9, rs10923931 in NOTCH2, rs1153188 near DCD and rs9472138 near VEGFA) for three independent Japanese populations (first set, 1,630 type 2 diabetes patients vs 1,064 controls; second set, 1,272 type 2 diabetes patients vs 856 controls; third set, 486 type 2 diabetes patients vs 936 controls) using a TaqMan assay. The association of the SNP loci in each population was analysed using a logistic regression analysis, adjusting for age, sex and BMI, and the data were evaluated by a meta-analysis.A meta-analysis for the three case-control studies identified a nominal association of rs864745 in JAZF1 with type 2 diabetes (OR 1.148, 95% CI 1.034-1.275, p = 0.0098, corrected p = 0.069). The association of other loci did not reach statistically significant levels (nominal p0.05).From these results the contribution of these seven loci in conferring susceptibility to type 2 diabetes is considered minor in the Japanese population, if they are present.

Recent studies have shown that bone marrow transplantation reduces hyperglycaemia in a mouse model of diabetes induced by streptozotocin. However, the essential factors for the improvement of hyperglycaemia by bone marrow transplantation have not been fully elucidated. The aim of this study was to search for such factors.We investigated the effect of irradiation to whole body, to abdomen alone or to whole body excluding abdomen, followed by infusion or no infusion of bone marrow cells. We also investigated the effect of bone marrow transplantation on beta cell-specific vascular endothelial growth factor-A gene (Vegfa) knockout mice.Bone marrow transplantation improved streptozotocin-induced hyperglycaemia and partially restored islet mass. This change was associated with increased islet vascularisation. Among the other methods investigated, low-dose irradiation of the whole body without infusion of bone marrow cells also improved blood glucose level. In streptozotocin-treated beta cell-specific Vegfa knockout mice, which exhibit impaired islet vascularisation, bone marrow transplantation neither improved hyperglycaemia, relative beta cell mass nor islet vascularisation.Our results indicate that whole body irradiation is essential and sufficient for restoration of beta cell mass after streptozotocin treatment independent of infusion of bone marrow cells. Vascular endothelial growth factor-A produced in beta cells is also essential for this phenomenon.

Udgivelsesdato: 2008-Sep We conducted a genome-wide association study using 207,097 SNP markers in Japanese individuals with type 2 diabetes and unrelated controls, and identified KCNQ1 (potassium voltage-gated channel, KQT-like subfamily, member 1) to be a strong candidate for conferring susceptibility to type 2 diabetes. We detected consistent association of a SNP in KCNQ1 (rs2283228) with the disease in several independent case-control studies (additive model P = 3.1 x 10(-12); OR = 1.26, 95% CI = 1.18-1.34). Several other SNPs in the same linkage disequilibrium (LD) block were strongly associated with type 2 diabetes (additive model: rs2237895, P = 7.3 x 10(-9); OR = 1.32, 95% CI = 1.20-1.45, rs2237897, P = 6.8 x 10(-13); OR = 1.41, 95% CI = 1.29-1.55). The association of these SNPs with type 2 diabetes was replicated in samples from Singaporean (additive model: rs2237895, P = 8.5 x 10(-3); OR = 1.14, rs2237897, P = 2.4 x 10(-4); OR = 1.22) and Danish populations (additive model: rs2237895, P = 3.7 x 10(-11); OR = 1.24, rs2237897, P = 1.2 x 10(-4); OR = 1.36).

Ectopic activation of hedgehog (HH) signalling in pancreas induces various abnormal morphogenetic events in the pancreas. This study analysed the dose-dependent requirement of patched homologue 1 (PTCH1), a negative regulator of HH signalling on pancreatic development. We used a recessive spontaneous mutant mouse denoted as mes which carries a mutated Ptch1 resulting in deletion of the most carboxy-terminal cytoplasmic domain of the PTCH1 protein. In this study, we analysed pancreatic morphology in Ptch1 +/+ , Ptch1 +/mes , Ptch1 +/−, Ptch1 mes/me s and Ptch1 −/mes mouse embryos, as well as the islet mass in adult Ptch1 +/+, Ptch1 +/mes and Ptch1 +/− mice. Until embryonic day (E) 12.5, no obvious abnormality of pancreas was observed in any of the Ptch1 mutants. The levels of PDX1 and glucagon were also not evidently different among the mice genotypes studied. Thereafter, morphological abnormalities appeared in the Ptch1 mutant mice. The beta, alpha and exocrine cell masses decreased at E18.5 in parallel with increased HH signalling, with beta cell mass showing the highest sensitivity to HH signalling with a significant decrease even in Ptch1 +/mes mice. Adult Ptch1 +/− mice also showed a significant decrease in beta cell mass compared with wild-type mice. Our findings indicate that the carboxy-terminal domain of Ptch1 is essential for pancreatic development. In addition, the loss of Ptch1 function decreases both the endocrine and exocrine cell mass in a dose-dependent manner, with beta cells particularly sensitive to changes in HH signalling.

Diabetes mellitus is an independent risk factor for acute myocardial infarction. Thus, a surveillance study was conducted as part of studies to create a national database related to electrocardiogram (ECG)-gated myocardial perfusion single-photon emission computed tomography (SPECT) of ischemic heart disease.Single-photon emission computed tomography was conducted in patients with type 2 diabetes mellitus and their prognoses will be followed for 3 years, stratified by patients' clinical background and SPECT findings.A total of 513 patients from 50 institutions were enrolled in this study, 297 of whom were men (age 66.2 +/- 0.4 years, mean +/- SEM) and 261 women (age 67.8 +/- 0.5 years). They have a history of retinopathy (25.3%), neuropathy (19.9%), cerebrovascular disorder, chronic obstructive pulmonary disease, and photocoagulation. Major risk factors for present disease were hypertension (82.3%) and hyperlipidemia (79.7%). In 244 patients (129 men and 115 women), body mass index (BMI) was 25 or more. Fifty-two of them (10.1%) underwent coronary angiography; of these, 26 (50.0%) had no coronary artery lesions with 75% or more stenosis, and only 1 (1.9%) had a left main trunk with 50% or more stenosis. An overwhelming majority of patients (94.3%) underwent SPECT imaging by a 1-day stress-followed-by-rest procedure. Stress procedure was exercise in most (70.8%) patients, followed by dipyridamole infusion in 14.6%, adenosine infusion in 6.6%, and adenosine triphosphate infusion in 5.7%. Endpoint of stress examination was most often fatigue in lower limbs (40.7%), followed by completion of pharmacological stress protocol (28.7%), and achievement of target heart rate (26.3%). The largest number of patients (198, 38.6%) received (99m)Tc-tetrofosmin at an initial dosage of 200-300 MBq (mean 331 +/- 3 MBq) followed by a second dosage of 700-800 MBq (mean 748 +/- 8 MBq). Among them, 491 (95.7%) received some kind of therapeutic drug: hypoglycemic drugs were used by the largest number (83.2%), followed by hypotensive (66.7%), hypolipidemic (40.7%), and antiplatelet drugs (27.7%), vasodilators (5.5%), and antioxidants and others (2.3%).This study was designed to clarify the correlation between coronary artery disease and diabetes mellitus as its risk factor based on the clinical and imaging findings. Patient enrollment was closed on September 30, 2005, and follow-up is now under way.

Endothelial cells are considered to be essential for normal pancreatic beta cell function. However, there have been no reports showing their importance for beta cell function.Using mice with disrupted vascular endothelial growth factor-A gene specifically in beta cells, we investigated the relation between islet vascular structure and beta cell function.Mice with disrupted vascular endothelial growth factor-A gene specifically in beta cells had reduced islet vascular density with impaired formation of endothelial fenestration. While their fasting glucose and body weight were comparable with control mice, their glucose- and tolbutamide-induced rapid insulin release were impaired, thus resulting in glucose intolerance. On the other hand, glucose and KCl enhanced the levels of insulin secreted from islets isolated from these mice. In addition, the production of soluble N-ethylmaleimide-sensitive factor attachment protein receptors in the islets was increased. Insulin content and expression of insulin I and pancreas duodenum homeobox 1 mRNA in the islets were also increased.Our results indicate that an abnormal quality and quantity of blood vessels due to reduced expression of vascular endothelial growth factor-A in beta cells could be a cause of impaired insulin secretion without impairment of beta cell function.

Although genetic susceptibility plays an important role in the pathogenesis of type 2 diabetes, most of the genes that influence susceptibility to type 2 diabetes have yet to be identified. Krüppel-like transcription factors are known to play important roles in development and cell differentiation, and have recently been implicated in the pathogenesis of type 2 diabetes. The present study aimed to examine the associations of single nucleotide polymorphisms (SNPs) in genes encoding members of the Krüppel-like-factor (KLF) family with type 2 diabetes in a large cohort of Japanese subjects.We genotyped 33 SNP loci found in 12 KLF genes in subjects with type 2 diabetes and in subjects from the general population using the PCR-Invader assay. We also examined the effects of the overexpression of KLF7 on adipogenesis in 3T3-L1 cells.We identified a significant association between an SNP in KLF7 and type 2 diabetes (A vs C: p=0.004 after Bonferroni's correction, odds ratio=1.59, 95% CI 1.27-2.00). The expression of Klf7 decreased in response to the differentiation of 3T3-L1 adipocytes, and the overexpression of KLF7 resulted in significant inhibition of adipogenesis in 3T3-L1 cells.These results indicate that the gene encoding KLF7 is a novel candidate for conferring genetic susceptibility to type 2 diabetes.

We have shown previously that the SLC12A3 +78G/A polymorphism in exon 23 (Arg913Gln) was a new candidate for conferring susceptibility to diabetic nephropathy. The aim of this study was to confirm the effect of this polymorphism on the elevation of urinary albumin excretion in type 2 diabetic patients.We retrospectively studied 264 Japanese patients with type 2 diabetes over a ten-year period. The subjects were classified into two groups: (1) persistent normoalbuminuria or microalbuminuria, or improvement from microalbuminuria to normoalbuminuria (group N); and (2) progression from normoalbuminuria to microalbuminuria or overt proteinuria, or progression from microalbuminuria to overt proteinuria (group P). They were assessed for association with the +78G/A polymorphism.The frequency of the +78A allele was significantly higher in group N than in group P (10% vs 1%, p=0.021). By logistic regression analysis and discriminant analysis, the substituted allele was shown to be an independent factor correlating negatively to the elevation of albumin excretion (p=0.043 and 0.022, respectively).The SLC12A3 +78A(+) genotype may have a protective effect against the development and/or progression of diabetic nephropathy in Japanese type 2 diabetic patients.

Bone marrow cells contain at least two distinct types of stem cells which are haematopoietic stem cells and mesenchymal stem cells. Both cells have the ability to differentiate into a variety of cell types derived from all three germ layers. Thus, bone marrow stem cells could possibly be used to generate new pancreatic beta cells for the treatment of diabetes. In this study, we investigated the feasibility of bone marrow-derived cells to differentiate into beta cells in pancreas.Using green fluorescent protein transgenic mice as donors, the distribution of haematogenous cells in the pancreas was studied after bone marrow transplantation.In the pancreas of green fluorescent protein chimeric mice, green fluorescent protein-positive cells were found in the islets, but none of these cells expressed insulin. Previous data has suggested that tissue injury can recruit haematopoietic stem cells or their progeny to a non-haematopietic cell fate. Therefore, low-dose streptozotocin (30 or 50 mg/kg on five consecutive days) was injected into the mice 5 weeks after bone marrow transplantation, but no green fluorescent protein-positive cells expressing insulin were seen in the islets or around the ducts of the pancreas.Our data suggests that bone marrow-derived cells are a distinct cell population from islet cells and that transdifferentiation from bone marrow-derived cells to pancreatic beta cells is rarely observed.

We evaluated the relationship of an alanine or valine polymorphism at amino acid sequence 16 [Val(16)Ala] of manganese superoxide dismutase (Mn-SOD) with diabetes and diabetic nephropathy in Japanese type 2 diabetic patients. Val(16)Ala genotyping of Mn-SOD was done by polymerase chain reaction-restriction fragment length polymorphism with a restriction enzyme ( Bsaw I) in 478 Japanese type 2 diabetic patients and 261 nondiabetic Japanese healthy subjects. The genotype distribution of diabetic and nondiabetic subjects was then compared, and the association of genotype with diabetic nephropathy was evaluated in the diabetic patients. The allele frequency and genotype of the diabetic patients were not different from those of the healthy nondiabetic subjects. The VV type showed a significantly higher frequency in the diabetic patients with nephropathy than did the AA or VA type [VV type: normoalbuminuria 70.8%, microalbuminuria 84.8% (P = 0.0057), macroalbuminuria 84.1% (P = 0.0128)]. Furthermore, logistic regression analysis showed that this polymorphism is associated with diabetic nephropathy independently (odds ratio = 0.461925, P = 0.03). Accordingly, the Val(16)Ala polymorphism of Mn-SOD may be unrelated to the etiology of type 2 diabetes, but it seems to be associated with diabetic nephropathy in Japanese type 2 diabetic patients.

Aims/hypothesis. Chronic hyperglycaemia in patients with Type II (non-insulin-dependent) diabetes mellitus often leads to a decline in glucose-responsive insulin secretion from pancreatic beta cells, a phenomenon called glucose toxicity. Upon hyperglycaemia, glycation reaction occurs in the beta cells and induces oxidative stress. To understand the molecular basis of the beta-cell glucose toxicity, we investigated the possible effects of glycation on the expression and enzymatic activity of glucokinase, which plays a crucial part in glucose-responsive insulin secretion. Methods. Glycation and reactive oxygen species were induced in HIT-T15 cells by treatment with d-ribose and effects on glucokinase gene transcription, glucokinase protein amount, glucose phosphorylation activity, and DNA-binding activities of putative glucokinase gene transcription factors were evaluated. Results. When glycation was induced in HIT-T15 cells, the activity of the human glucokinase gene beta-cell-type promoter was suppressed substantially (83 % reduction at 60 mmol/l d-ribose). Also, similar reductions in mRNA and protein amounts of glucokinase and in the Vmax of its enzymatic activity were observed. In agreement with the reduction in the promoter activity, the two major transcription factors of the glucokinase gene, the Pal-binding factor and PDX-1, reduced their binding to their target sequences in the glucokinase gene promoter in glycation-induced HIT cells. Because these effects of d-ribose were counteracted by aminoguanidine or N-acetylcysteine, reactive oxygen species, generated by the glycation reaction, appears to be involved in the phenomena. Conclusion/interpretation. The induction of the glycation reaction, which is known to occur in pancreatic beta cells in chronic hyperglycaemia, suppresses the glucokinase gene transcription and its enzymatic activity. Thus, hyperglycaemia-dependent inhibition of glucokinase activity could in part explain beta-cell glucose toxicity. [Diabetologia (1999) 42: 1417‐1424]

The purpose of this study was to evaluate the efficacy and feasibility of a newly developed diabetes patient education program consisting of a three-day hospitalization and a six-month follow-up by telephone counseling for patients with mild type 2 diabetes or impaired glucose tolerance (IGT) by a randomized controlled trial (RCT) method. Fifty-two patients with mild type 2 diabetes or IGT (HbAlc

Atherosclerotic changes have not been demonstrated directly in asymptomatic hyperglycaemic non-diabetic subjects, although high mortality due to coronary heart disease has been reported. We measured arterial wall thickness non-invasively, in order to directly demonstrate atherosclerosis of the carotid arteries of hyperglycaemic non-diabetic subjects and to evaluate its risk factors. The thicknesses of the intimal plus medial complex (IMT) of the carotid arteries of 112 asymptomatic hyperglycaemic non-diabetic subjects (aged 22-81, 95 males and 17 females) were compared with those of 55 healthy male subjects and 211 non-insulin-dependent NIDDM male diabetic patients. The subjects were subgrouped into impaired glucose-tolerant (IGT) subjects who had a 2-h glycaemic level of more than 7.8 mmol/l, and non-IGT subjects whose 2-h glycaemic levels were within 6.7-7.7 mmol/l. Non-IGT and IGT subjects showed significantly greater IMTs than age-matched healthy males and showed no significant differences compared to age-matched NIDDM patients. Multivariate analysis demonstrated that the risk factors for IMT of non-IGT and IGT subjects were age and systolic blood pressure. According to data on the accumulation of atherogenic risks (hypertension, dyslipidaemia, and smoking), IMT increased linearly in non-IGT and IGT subjects. However, non-IGT and IGT subjects without hyperlipidaemia, hypertension, or smoking risk still had significantly greater IMT than age-matched normal males (1.019 +/- 0.063 vs 0.770 +/- 0.111 mm, p0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

BackgroundThe coexistence of type 2 diabetes mellitus and hypertension increases the risk of cardiovascular diseases. The U.K. Prospective Diabetes Study has shown that blood pressure control as well as blood glucose control is efficient for prevention of complications in hypertensive patients with diabetes mellitus. However, some reports have shown that it is difficult to control the blood pressure and the concomitant use of a plurality of drugs is needed in hypertensive patients with diabetes mellitus. In recent years renin-angiotensin system depressants are increasingly used for the blood pressure control in diabetic patients. Particularly in Japan, angiotensin II (A II) antagonists are increasingly used. However, there is no definite evidence of the point of which is efficient for the control, the increase in dose of A II antagonist or the concomitant use of another drug, in hypertensive patients whose blood pressure levels are inadequately controlled with A II antagonist.Methods/DesignHypertensive patients of age 20 years or over with type 2 diabetes mellitus who have been treated by the single use of AII antagonist at usual doses for at least 8 weeks or patients who have been treated by the concomitant use of AII antagonist and an antihypertensive drug other than calcium channel blockers and ACE inhibitors at usual doses for at least 8 weeks are included.DiscussionWe designed a multi-center, prospective, randomized, open label, blinded-endpoint trial,ADVANCED-J, to compare the increases in dose of A II antagonist and the concomitant use of a Ca-channel blocker (amlodipine) and A II antagonist in hypertensive patients with diabetes mellitus, whose blood pressure levels were inadequately controlled with A II antagonist. This study is different from the usual previous studies in that home blood pressures are assessed as indicators of evaluation of blood pressure. TheADVANCED-Jstudy may have much influence on selection of antihypertensive drugs for treatment in hypertensive patients with diabetes mellitus. It is expected to give an important hint for considering the validity of selection of antihypertensive drugs from the aspects not only of the antihypertensive effect but medical cost-effectiveness.

Background The Cardiovascular Risk Evaluation in people with type 2 Diabetes on Insulin Therapy (CREDIT) study is an international, multicenter, observational study designed to assess metabolic parameters and cardiovascular risk of patients with type 2 diabetes mellitus (T2DM) on insulin therapy. The present report summarizes results at baseline and 1-year follow-up for the cohort of Japanese patients. Methods Male and female patients (n = 511), aged >40 years, with T2DM for >1 year, treated with insulin therapy for ≥1 month and

Background To investigate the clinical differences between pulse wave velocity and augmentation index in diabetic retinopathy. Methods The subjects were 201 patients with type 2 diabetes. These subjects were measured for both augmentation index (AI) and brachial-ankle pulse wave velocity (baPWV) by a pulse wave analyzer. The relationships between AI, baPWV, and diabetic retinopathy were examined. Results BaPWV was significantly higher in patients with diabetic retinopathy than in individuals without the disease. (20.13 ± 3.66 vs.17.14 ± 3.60 m/s p < 0.001) AI was higher in patients with diabetic retinopathy, but not significantly. (19.5 ± 15.2 vs. 14.8 ± 20.5% p = 0.14) The association between baPWV and diabetic retinopathy remained statistically significant after adjustment. (Odds ratio: 1.21 Per m/s, 95% confidence interval: 1.07–1.37) On the other hand, the association between AI and diabetic retinopathy was not statistically significant. (Odds ratio: 1.01 Per %, 95% confidence interval: 0.98–1.03) Conclusion BaPWV is associated with diabetic retinopathy, but AI is not. The clinical significance appears to be different between PWV and AI in patients with diabetes.

Background Secondary treatment of arteriosclerosis may be applicable for the primary prevention of atherosclerosis in diabetic patients. This prospective, 2-year follow-up study was designed to determine the efficacy and safety of antiplatelet therapy in the prevention of atherosclerosis of diabetic subjects.

Recently a new automatic device that measures brachial-ankle pulse wave velocity using an oscillometric method has been developed. However, the practical significance of brachial-ankle pulse wave velocity measurement remains uncertain. The purpose of this study was to examine the association between brachial-ankle pulse wave velocity and symptomatic cerebral infarction in patients with type 2 diabetes. One thousand sixty six patients with type 2 diabetes were studied cross-sectionally. Measurements of brachial-ankle pulse wave velocity were made using the automatic device. Logistic regression analysis was used to calculate the odds ratio for cerebral infarction. The presence of symptomatic cerebral infarction was confirmed in 86 patients. In these patients brachial-ankle pulse wave velocity was found to be significantly higher than in patients without cerebral infarction (18.94 ± 4.95 versus 16.46 ± 3.62 m/s, p < 0.01). The association between brachial-ankle pulse wave velocity and cerebral infarction remained significant after adjustment for traditional risk factors. There was an increasing odds ratio for each tertile of brachial-ankle pulse wave velocity, from the second tertile (odds ratio, 2.28; 95% confidence interval, 1.05 to 4.94), to the third (odds ratio, 2.53; 95% confidence interval, 1.09 to 5.86). Overall, we conclude that an increase in brachial-ankle pulse wave velocity is associated with symptomatic cerebral infarction in patients with type 2 diabetes.

Water-in-oil-in-water (W/O/W) insulin emulsions with a concentration of 100 U/ml of insulin were prepared, and the possible absorption of insulin in emulsion form was examined. The following results were obtained: W/O/W insulin emulsions were quite resistant to proteolytic enzymes in vitro. In the presence of pancreatic lipase, however, W/O/W insulin emulsion gradually lost its activity by the action of proteolytic enzymes. When administered to the jejunum at doses over 10 U/kg, a significant and consistent increase in plasma insulin was observed, followed by a fall in blood glucose. The infusion of W/O/W insulin emulsions into the jejunum was three to four times more effective than the administration of aqueous insulin. Insulin, when administered to the stomach, did not cause hypoglycemia at doses up to 150 U/kg. When W/O/W insulin emulsions were administered orally, on the other hand, definite responses were observed in 3 out of 7 rabbits with 100 U/kg and in 4 out of 7 rabbits with 150 U/kg. For developing an effective method for oral administration of insulin, the present results indicate a possible means of protecting insulin molecule from proteolytic destruction, and of facilitating intestinal absorption of insulin.

The interaction of nuclear protein extracted from rat liver and 5'-flanking DNA of the human insulin receptor gene was investigated with the aid of gel mobility shift analysis. When 5'-flanking DNA (-1255/-1206 or -385/-345 base pairs) was incubated with nuclear protein, two or three 32P-DNA species (protein binding DNA fragment(s) and free DNA fragment) were detected. These bands did not disappear in spite of increasing amounts of synthetic poly(dI-dC), showing that nuclear protein binds specifically to 5'-flanking DNA of the insulin receptor gene. Increasing amounts of long terminal repeat of mouse mammary tumour virus resulted in a reciprocal decrease in nuclear protein binding to 5'-flanking DNA of insulin receptor gene. These results suggest that 5'-flanking DNA of insulin receptor gene binds to the same nuclear protein to which long terminal repeat of mouse mammary tumour binds.

The effect of glucocorticoid (dexamethasone) on insulin receptor mRNA was examined in the IM-9 cell line by dot hybridization analysis using insulin receptor c-DNA probe (phINSR 13-1). Insulin receptor mRNA was found in a dose- and time-dependent manner, to increase during a 24-h culture with glucocorticoid. Although there has been some dispute about the effect of glucocorticoid on degradation of the insulin receptor itself, we have found glucocorticoid had no significant effect on the degradation rate of insulin receptor mRNA. These results suggest that glucocorticoid has the effect of increasing de novo synthesis of insulin receptor mRNA. But the molecular mechanism of glucocorticoid's effect still needs to be investigated.

A needle-type glucose sensor has been developed using a platinum electrode covered with immobilized glucose oxidase. Experiments with albumin-saline solution in vitro showed that at 5.5 mmol/l glucose concentration the output current generated was 1.2 +/- 0.4 nA (mean +/- SD). The current increased as a linear function of glucose concentration over the range (0-27.7 mmol/l). The response time to reach 90% of the final plateau value was 16.2 +/- 6.2s. The signal-to-noise ratio of the sensor was 15.8 +/- 2.6 decibels. The temperature coefficient in output was 2.3 +/- 1.0%/degrees C. The current output was not affected significantly by changes in oxygen tension of the solution in the range 25-150 mmHg. In vivo, the output current of sensors inserted into the subcutaneous tissues of dogs was directly related to blood glucose concentrations after oral glucose or meals. Daily checking of the sensors maintained in subcutaneous tissues in five dogs showed that the sensitivity decreased gradually to 87.2 +/- 7.6% at 72 h, and dropped significantly to 57.4 +/- 7.0% of the initial output by 96 h. A wearable artificial endocrine pancreas (18.0 x 17.7 x 7.9 cm, 700 g) was developed, consisting of a needle-type glucose sensor, a microcomputer system and a pump driving mechanism. Three pancreatectomized dogs were fitted with the system by inserting the sensor into subcutaneous tissue. By renewing the sensor every fourth day, the device could maintain the daily glucose variations in diabetic dogs within the range 5-9.5 mmol/l for 7 days.