A low-frequency GLIS3 variant associated with resistance to Japanese type 1 diabetes.

The role of low-frequency variants in type 1 diabetes (T1D) susceptibility still remains to be clarified. In the present study, we analyzed low-frequency variants of the T1D candidate genes in Japanese. We first screened for protein-changing variants of 24 T1D candidate genes in 96 T1D patients and 96 control subjects, and then the association with T1D was tested in 706 T1D patients and 863 control subjects recruited from the collaborating institutions in Japan. In total, 56 protein-changing variants were discovered; among them, 34 were low-frequency variants (allele frequency < 5%). The association analysis of the low-frequency variants revealed that only the A908V variant of GLIS3 was strongly associated with resistance to T1D (Haldane's odds ratio = 0.046, p = 8.21 × 10(-4), and pc=2.22 × 10(-2)). GLIS3 is a zinc finger transcription factor that is highly expressed in pancreatic beta cells, and regulates beta cell development and insulin gene expression. GLIS3 mRNA is also moderately expressed in the human thymus. The precise mechanism responsible for the association is unclear at present, but the A908V variant may affect autoimmunity to the GLIS3 protein itself; the 908V containing epitope may induce central or peripheral tolerance more efficiently than that of 908A.

Hypoglycemic effects of colestimide on type 2 diabetic patients with obesity.

Recent studies have shown colestimide, a bile acid-binding resin, to also exert a glucose-lowering effect via amelioration of insulin resistance. To evaluate the effects of colestimide on glucose metabolism and to elucidate the underlying mechanism, we conducted a 6-month, open-label pilot study on 43 type 2 diabetic patients with obesity (BMI ≥ 25). The subjects were randomized to either treatment with colestimide 4g/day (T group, n=23) or continuation of their current therapy (C group, n=20). In the T group patients, mean HbA1c and fasting glucose improved markedly (from 7.71 ± 0.32% to 6.97 ± 0.20%; from 147.4 ± 7.3mg/dL to 127.0 ± 5.0mg/dL, respectively), while obesity-related parameters, i.e. body weight, waist circumference, and visceral fat and subcutaneous fat as determined by umbilical slice abdominal CT, showed no significant changes. Fractionation analyses of serum bile acids revealed significantly increased cholic acids (CA) and decreased chenodeoxycholic acids (CDCA) in the T group patients. However, no correlation was observed between these changes and ΔHbA1c. According to logistic regression analysis, baseline HbA1c was the only variable predicting the decrease of HbA1c (>0.5%) among sex, age, BMI, total cholesterol, ΔCA and ΔCDCA. The index of insulin resistance, i.e. HOMA-R, did not improve, and the index of ß cell function, i.e. HOMA-ß, actually increased significantly. These results suggests that, in obese patients with type 2 diabetes, the mechanism underlying improved glycemic control with colestimide treatment involves enhanced ß cell activity rather than improved insulin resistance.

Analysis of the HLA and non-HLA susceptibility loci in Japanese type 1 diabetes.

BACKGROUND: We previously reported the associations of human leukocyte antigen (HLA) (DRB1 and DQB1), INS, CTLA4, IL2RA, ERBB3 and CLEC16A with Japanese type 1 diabetes (T1D). In this study, we jointly analysed these loci in addition to IFIH1 and IL7R. METHODS: A maximum of 790 T1D patients and 953 control subjects were analysed. HLA was determined by sequencing-based typing. Seven non-HLA single nucleotide polymorphisms were genotyped using TaqMan assay. RESULTS: HLA DRB1*0405, DRB1*0901 and DRB1*0802-DQB1*0302 haplotypes were positively associated with T1D, while the DRB1*15 haplotypes were negatively associated. Non-HLA single nucleotide polymorphisms, INS, IL2RA, ERBB3, CLEC16A and IL7R were associated with T1D. By a prediction model using the HLA loci alone (HLA model) or the non-HLA loci alone (non-HLA model), it was revealed that the cumulative effect of the non-HLA model was much weaker than that of the HLA model (average increase in odds ratio: 1.17 versus 3.14). Furthermore, the area under the receiver operating characteristic curve of the non-HLA model was also much smaller than that of the HLA model (0.65 versus 0.81, p<10(-11)). Finally, a patient-only analysis revealed the susceptible HLA haplotypes and the risk allele of INS to be negatively associated with slower onset of the disease. In addition, the DRB1*0901 haplotype and the risk alleles of ERBB3, CLEC16A and CTLA4 were positively associated with the co-occurrence of thyroid autoimmunity. CONCLUSIONS: Although several non-HLA susceptibility genes in Japanese were confirmed trans-racially and appear to contribute to the heterogeneity of the clinical phenotypes, the cumulative effect on the ability to predict the development of T1D was weak.

Phenotype and genotype characteristics of age-related macular degeneration in a Japanese population.

PURPOSE: To describe phenotype and genotype characteristics of age-related macular degeneration (AMD) in Japanese patients. DESIGN: A case-control study. PARTICIPANTS: A total of 550 case-control samples composed of 408 consecutive AMD cases and 142 controls. METHODS: Clinical information assessing age, gender, affected eyes, fundus features, and fluorescein/indocyanine green angiograms were systematically evaluated. Four single nucleotide polymorphisms (SNPs; rs800292, rs1061170, rs1410996, rs2274700) in the complement factor H (CFH) gene, 1 SNP (rs11200638) in the high-temperature requirement factor A1 (HTRA1) gene, 3 SNPs (rs699947, rs1570360, rs2010963) in the vascular endothelial growth factor (VEGF) gene, and 4 SNPs (rs12150053, rs12948385, rs9913583, rs1136287) in the pigment epithelium-derived factor (PEDF) gene were assessed using TaqMan technology. MAIN OUTCOME MEASURES: The clinical phenotype information and genotypes of CFH, HTRA1, VEGF, and PEDF polymorphisms. RESULTS: Of Japanese patients with neovascular AMD (nAMD), 219 (58.7%) had typical nAMD and 154 (41.3%) had polypoidal choroidal vasculopathy (PCV). The frequency of bilateral exudative involvement was similar between typical nAMD (15.5%) and PCV (13.6%) (P = 0.613). Significant soft drusen were observed in the fellow eyes of 88 (47.6%) of 185 patients with unilateral typical nAMD and in 25 (18.8%) of 133 patients with unilateral PCV (P = 1.24x10(-7)). A serous pigment epithelium detachment was seen in 55 (25.1%) of 219 patients with typical nAMD and in 64 (41.6%) of 154 patients with PCV. A significant association was noted in CFH-rs800292, CFH-rs1410996, CFH-rs2274700, and HTRA1-rs11200638 with AMD development (P = 2.36x10(-5), 7.18x10(-5), 7.18x10(-5), 2.70x10(-7), respectively; population attributable risk = 57.3%, 57.8%, 57.8%, and 58.9%, respectively). We estimated the highest-risk group to have an approximately 70-fold greater risk of nAMD compared with the lowest-risk group when analyzing a combination of 4 SNPs in the CFH and HTRA1 genes. CONCLUSIONS: The Japanese AMD phenotype is characterized by a higher frequency of PCV, male predominance, and lower frequency of bilateral presentation compared with Caucasian AMD. Genotype analyses demonstrate a significant population attributable risk for SNPs in the CFH and HTRA1 genes and demonstrate joint effects for both genes. Gene variants in both CFH and HTRA1 contribute significantly to the AMD phenotype in a Japanese population.

Simultaneous development of Graves' disease and type 1 diabetes during anti-programmed cell death-1 therapy: A case report.

We present the first case of simultaneous development of Graves' disease and type 1 diabetes during anti-programmed cell death 1 therapy. A 48-year-old man with parotid gland adenocarcinoma and lung metastasis had received five courses of nivolumab. Fourteen days after administration of the sixth course, his casual plasma glucose and hemoglobin A1c levels were 379 mg/dL and 7.2%, respectively. Furthermore, thyrotoxicosis was detected with a blood test. Serum total ketone body and thyroid-stimulating hormone receptor antibody levels increased, and serum C-peptide level decreased to 0.01 ng/mL thereafter. Thus, we concluded that he simultaneously developed anti-programmed cell death 1 therapy-associated type 1 diabetes and Graves' disease. Among Japanese patients with autoimmune polyglandular syndrome type III, the frequency of human leukocyte antigen-DRB1*04:05 is higher in those with both type 1 diabetes and Graves' disease. Our case had human leukocyte antigen-DRB1*04:05, which might be associated with the simultaneous development of the two diseases.

Association of type 1 diabetes with two Loci on 12q13 and 16p13 and the influence coexisting thyroid autoimmunity in Japanese.

CONTEXT: Recent genome-wide association studies have identified several novel type 1 diabetes (T1D) loci in white populations. OBJECTIVE: In line with recent findings, we conducted a replication study of two loci on chromosome 12p13 and 16p13 and assessed their potential associations with thyroid autoimmunity in a Japanese population. SUBJECTS AND METHODS: Two single-nucleotide polymorphisms (SNPs), rs2292399 in ERBB3 on 12q13 and rs2903692 in CLEC16A (or KIAA0350) on 16p13, were analyzed in Japanese subjects consisting of 735 T1D patients, 330 patients with autoimmune thyroid disease (AITD), and 621 control subjects. RESULTS: According to a case-control study and logistic regression adjusting for sex and age, we observed that these SNPs in ERBB3 and CLEC16A were both significantly associated with T1D, with the risk alleles being consistent with those in white populations [adjusting odds ratio by multiplicative model: 1.37 (1.13-1.67), P = 0.001; and 1.28 (1.02-1.60), P = 0.030, respectively]. In both SNPs, the association was suggested to be stronger in T1D complicated with AITD (Graves' disease, Hashimoto's thyroiditis, or thyroid autoantibodies). Furthermore, a joint analysis, with the INS and CTLA4 SNPs, revealed that CTLA4 rs3087243, ERBB3 rs2292399, and CLEC16A rs2903692, but not INS rs689, were significant risk factors for the cooccurrence of AITD in Japanese T1D. CONCLUSION: We confirmed two loci on 12q13 and 16p13 that were identified by the independent genome-wide association studies in white populations, thus suggesting that these loci contribute to T1D susceptibility across different ethnic groups. In addition, these loci may also be associated with the cooccurrence of thyroid autoimmunity in T1D.

Intrinsic insulin secretion capacity might be preserved by discontinuing anti-programmed cell death protein 1 antibody treatment in 'anti-programmed cell death protein 1 antibody-induced' fulminant type 1 diabetes.

Intrinsic insulin secretion capacity may be preserved by discontinuing anti-PD-1 antibody treatment in 'anti-PD-1 antibody-induced'fulminant type 1 diabetes.

Insulin gene/IDDM2 locus in Japanese type 1 diabetes: contribution of class I alleles and influence of class I subdivision in susceptibility to type 1 diabetes.

CONTEXT: It is suggested that insulin autoimmunity plays an important role in the development of type 1 diabetes in humans. However, the association between insulin gene (INS) region (IDDM2) and type 1 diabetes has been uncertain in Asians. OBJECTIVE: A multicenter collaboration study was conducted to clarify the role of the IDDM2 region in Japan. SUBJECTS AND METHODS: In total, 661 patients with type 1 diabetes and 706 control subjects were enrolled. The INS variable number of tandem repeat (VNTR) class I/class III status was estimated by genotyping the -23 HphI single nucleotide polymorphism. From surrounding polymorphisms across the insulin gene, we also inferred haplotypes bearing INS VNTR lineages. RESULTS: The frequency of the class I allele was 99.3% in patients and 96.7% in controls (P < 10(-5)), and the class I/III or III/III genotype was found in 1.4% of patients and in 6.4% of controls [odds ratio (OR) 0.20, P < 10(-5)]. The class I subdivision revealed IC to increase significantly in patients with type 1 diabetes (P = 0.002), whereas ID did not; the distribution of IC and ID was significantly different between patients and controls (P = 0.014). CONCLUSION: The present study certainly shows that the IDDM2 region is also a susceptibility locus in the Japanese population. Furthermore, it was revealed that IC may be more susceptible to type 1 diabetes than ID, which could be evidence that the INS VNTR itself confers susceptibility to type 1 diabetes.

Cytotoxic T-lymphocyte associated antigen 4 gene polymorphisms and autoimmune thyroid disease: a meta-analysis.

CONTEXT: Cytotoxic T-lymphocyte associated antigen 4 (CTLA-4) polymorphisms have been widely examined for their associations with autoimmune thyroid diseases [Graves' disease (GD) and Hashimoto thyroiditis (HT)], but their relative population effect remains unclear. OBJECTIVE: The aim was to generate large-scale evidence on whether the CTLA-4 polymorphisms (A49G and CT60) and haplotypes thereof increase the susceptibility to GD and/or HT. DESIGN, SETTING, AND PARTICIPANTS: Meta-analyses of group-level data were reviewed from 32 (11,019 subjects) and 12 (4,479) published and unpublished studies for the association of the A49G polymorphism with GD and HT, respectively (PubMed and HuGeNet search until July 2006). There were 15 (n = 7246) and six (n = 3086) studies available for the CT60 polymorphism, respectively. Meta-analyses of individual-level data from 10 (4906 subjects) and five (2386) collaborating teams for GD and HT, respectively, were also reviewed. MAIN OUTCOME MEASURES: Association of gene variants and haplotypes with GD and HT was measured. RESULTS: Group-level data suggested significant associations with GD and HT for both A49G [odds ratios 1.49 (P = 6 x 10(-14)) and 1.29 (P = 0.001) per G allele, respectively] and CT60 [1.45 (P = 2 x 10(-9)) and 1.64 (P = 0.003) per G allele, respectively]. Results were consistent between Asian and Caucasian descent subjects. Individual-level data showed that compared with the AA haplotype, the risk conferred by the GG haplotype was 1.49 (95% confidence interval 1.31,1.70) and 1.36 (95% confidence interval 1.16,1.59) for GD and HT, respectively. Data were consistent with a dose-response effect for the G allele of CT60. CONCLUSION: The CT60 polymorphism of CTLA-4 maps an important genetic determinant for the risk of both GD and HT across diverse populations.

Possible Long-Term Efficacy of Sitagliptin, a Dipeptidyl Peptidase-4 Inhibitor, for Slowly Progressive Type 1 Diabetes (SPIDDM) in the Stage of Non-Insulin-Dependency: An Open-Label Randomized Controlled Pilot Trial (SPAN-S).

INTRODUCTION: We tested the hypothesis that dipeptidyl peptidase-4 (DPP-4) inhibitors are effective in preserving the ß-cell function for long-term periods in patients with slowly progressive type 1 diabetes (SPIDDM) or latent autoimmune diabetes in adults (LADA). METHODS: In the present open-label, randomized, controlled trial, 14 non-insulin-requiring diabetic patients with glutamic acid decarboxylase autoantibodies (GADAb) were randomly assigned to receive either sitagliptin (S group) or pioglitazone (P group). As a historical control, the Tokyo Study, in which non-insulin-dependent patients with SPIDDM were assigned to receive treatment by either insulin or sulfonylurea (SU), was used. RESULTS: On average, the ∑C-peptide values during the oral glucose tolerance test through the follow-up periods showed a nonsignificant increase in the S group (n = 6, n = 5 at 48 months) compared to the P group (n = 5, n = 2 at 48 months). In comparison to the data in the Tokyo Study, treatment by sitagliptin significantly influenced the longitudinal changes in the ∑C-peptide values with a more increased direction than insulin or SU, especially in patients with 48 months of follow-up (p = 0.014 and p = 0.007, respectively). Although the titers of GADAb were not significantly different between the S and P groups during the study, the change ratio of the GADAb titers from baseline was significantly inversely correlated with the change ratio of the ∑C-peptide values from baseline in the S group (p = 0.003); in particular, when the GADAb titers decreased from baseline, the ∑C-peptide values frequently increased. CONCLUSION: The present pilot trial suggests that treatment of SPIDDM/LADA by sitagliptin, a DPP-4 inhibitor, may be more effective in preserving the ß-cell function than insulin treatment for at least 4 years, possibly through the immune modulatory effects of DPP-4 inhibitors. CLINICAL TRIAL REGISTRATION: Japanese Clinical Trials Registry UMIN000003693.

The association of CTLA4 polymorphism with type 1 diabetes is concentrated in patients complicated with autoimmune thyroid disease: a multicenter collaborative study in Japan.

CONTEXT: Transracial studies are a powerful tool for genetic association studies of multifactorial diseases, such as type 1 diabetes. The low incidence of type 1 diabetes in Asian countries, however, makes it difficult to perform large-scale studies in Asia. OBJECTIVE: To overcome this, we have assembled a multicenter study group in Japan and studied the association of CTLA4 polymorphisms with type 1 diabetes relative to autoimmune thyroid disease (AITD) phenotypes. SUBJECTS: Subjects included a total of 1837 samples, including 1114 cases (769 with type 1 diabetes and 345 with AITD) and 723 control subjects. METHODS: The +6230G>A and +49G>A polymorphisms of CTLA4 as well as HLA-DRB1 and -DQB1 were genotyped. RESULTS: The +6230G>A polymorphism was significantly associated with type 1 diabetes complicated with AITD (odds ratio, 1.54; P = 0.027) and with AITD alone (odds ratio, 1.31; P = 0.045) but not with type 1 diabetes without AITD. The association with type 1 diabetes positive for autoantibodies to both pancreatic islets and thyroid was particularly strong (odds ratio, 1.87; P = 0.001). Type 1 diabetic patients with the disease-associated GG genotype were characterized by a significantly higher frequency of AITD (P = 0.013), of positivity for both AITD and antiislet autoantibody (P = 0.00086), and of high-risk HLA genotypes (P = 0.034). CONCLUSIONS: Given the high frequency of AITD in patients with type 1 diabetes, these data suggest the possibility that the association of CTLA4 with type 1 diabetes in previous studies may have been secondary to AITD, suggesting the importance of subclassification of type 1 diabetes relative to AITD in genetic studies.

A common polymorphism in the 5'-untranslated region of the VEGF gene is associated with diabetic retinopathy in type 2 diabetes.

Vascular endothelial growth factor (VEGF), a major mediator of vascular permeability and angiogenesis, may play a pivotal role in mediating the development and progression of diabetic retinopathy. In the present study, we examined the genetic variations of the VEGF gene to assess its possible relation to diabetic retinopathy in type 2 diabetic patients. Among seven common polymorphisms in the promoter region, 5'-untranslated region (UTR) and 3'UTR of the VEGF gene, genotype distribution of the C(-634)G polymorphism differed significantly (P = 0.011) between patients with (n = 150) and without (n = 118) retinopathy, and the C allele was significantly increased in patients with retinopathy compared with those without retinopathy (P = 0.0037). The odds ratio (OR) for the CC genotype of C(-634)G to the GG genotype was 3.20 (95% CI 1.45-7.05, P = 0.0046). The -634C allele was significantly increased in patients with nonproliferative diabetic retinopathy (non-PDR) (P = 0.0026) and was insignificantly increased in patients with proliferative diabetic retinopathy (PDR) (P = 0.081) compared with patients without retinopathy, although frequencies of the allele did not differ significantly between the non-PDR and PDR groups. Logistic regression analysis revealed that the C(-634)G polymorphism was strongly associated with an increased risk of retinopathy (P = 0.0018). Furthermore, VEGF serum levels were significantly higher in healthy subjects with the CC genotype of the C(-634)G polymorphism than in those with the other genotypes. These data suggest that the C(-634)G polymorphism in the 5'UTR of the VEGF gene is a novel genetic risk factor for diabetic retinopathy.

Efficacy of glimepiride in Japanese type 2 diabetic subjects.

We investigated the efficacy of glimepiride, a third-generation sulfonylurea (SU), in Japanese type 2 diabetic patients in whom glycemic control had been inadequate with a conventional SU, gliclazide or glibenclamide. A total of 172 Japanese type 2 diabetic patients (HbA1C > or = 7.0%), maintained on a conventional SU, were randomly assigned to the 3rd SU group (SU treatments switched to glimepiride) or the 2nd SU group (treatments not changed). The conventional SU was switched to the indicated doses of glimepiride (gliclazide 40 mg = glimepiride 1 mg, glibenclamide 2.5 mg = glimepiride 2 mg). After 6 months, glycemic control (HbA1C and fasting plasma glucose) had not changed significantly in either the 2nd or the 3rd SU group. The homeostasis assessment model of insulin resistance (HOMA-IR) in the 3rd SU group was decreased by more than 10% (p = 0.015), whereas no change was observed in the 2nd SU group. The triglyceride level was decreased by approximately 10% in the 3rd SU group, not a significant change (p = 0.080). Patients who had been treated with only SU, or treated with SU for a short time (less than 5 years), and who were also obese (BMI > or = 25) or had a high HOMA-IR (HOMA-IR > or = 3), showed significantly reduced insulin resistance. According to logistic regression analysis, high BMI ( > or = 25) was the only variable predicting that glimepiride would more effectively improve HbA1C than conventional SU treatment. In conclusion, switching conventional SUs to glimepiride reduced insulin resistance without improving glycemic control. A notable finding of this study is that glimepiride was more beneficial in obese than in non-obese Japanese type 2 diabetic patients.

Identification of a novel WFS1 mutation (AFF344-345ins) in Japanese patients with Wolfram syndrome.

Wolfram syndrome (WFS) is an autosomal recessive disorder characterized by early onset diabetes mellitus, progressive optic atrophy, sensorineural deafness and diabetes insipidus. Affected individuals may also have renal tract abnormalities as well as neurogical and psychiatric syndromes. WFS1 encoding a transmembrane protein was identified as the gene responsible for WFS. We report herein a Japanese family, of which two members had this syndrome. In the WFS1 gene of these patients, we identified a novel mutation, a nine nucleotide insertion (AFF344-345ins). In addition, one of these patients had preclinical hypopituitarism, which is an unusual feature of WFS. As only the two family members homozygous for the mutation showed WFS, these data support the notion that this mutation is the cause of WFS.

Endothelial nitric oxide synthase gene is associated with diabetic macular edema in type 2 diabetes.

OBJECTIVE: We examined the endothelial nitric oxide (eNOS) gene polymorphisms to assess its possible association with diabetic retinopathy and macular edema. RESEARCH DESIGN AND METHODS: A total of 226 patients with type 2 diabetes and 186 healthy subjects were studied. Type 2 diabetic patients consisted of 110 patients without retinopathy, 46 patients with nonproliferative diabetic retinopathy, and 71 patients with proliferative diabetic retinopathy. Diabetic macular edema was present in 48 patients. Three polymorphisms of the eNOS gene were determined: T-786C in the promoter region, 27-bp repeat in intron 4, and Glu298Asp in exon 7. RESULTS: Close linkage disequilibrium was observed between the T-786C polymorphism and the 27-bp repeat, as has been previously reported, but Glu298Asp was not in linkage disequilibrium with the other two polymorphisms. The eNOS gene polymorphisms were not significantly associated with the presence of retinopathy or with retinopathy severity or type 2 diabetes itself. However, by both association study and multiple logistic regression analysis, the T-786C and 27-bp repeat polymorphisms were significantly associated with a risk of developing macular edema with the -786C allele and the "a" allele increasing the risk. CONCLUSIONS: The present study suggests that the eNOS gene is a novel genetic risk factor for diabetic macular edema. The eNOS gene polymorphisms may contribute to the development of macular edema by impairing basal eNOS expression and resulting in the breakdown of the blood-retina barrier.

Efficacy and Clinical Characteristics of Liraglutide in Japanese Patients With Type 2 Diabetes.

BACKGROUND: Liraglutide was first released in Japan as a long-acting once-daily glucagon-like peptide-1 receptor agonist. The maximum dose in Japan is 0.9 mg/day, which is half of that used in the United States and the European Union (1.8 mg/day). The efficacy of this maximum allowable dose of liraglutide for Japanese patients and the profiles of those patients for whom this agent should be recommended remain unclear. METHODS: This study aimed to examine the effective use of liraglutide in Japanese type 2 diabetic patients. We administered liraglutide to 60 patients, who had been managed with oral hypoglycemic agents or diet and exercise therapy only, during a period of 6 months. RESULTS: Though HbA1c levels significantly decreased, by approximately 1.5%, after 6 months of liraglutide administration, no significant changes in body weights were observed. The 0.6 mg dose was effective in approximately 40% of patients. In contrast, the effects of a dose increase from 0.6 mg to 0.9 mg were small. The greatest efficacy, as shown by a 2.5% HbA1c decrease, was achieved in non-obese patients. Thus, efficacy decreased as the degree of obesity increased. In addition, efficacy was higher in patients who had a diabetes duration of less than 10 years and was also higher in the group that had a low sulfonylurea (SU) index, when we define the SU index as mg/glimepiride × years of treatment. CONCLUSIONS: As appetite suppressions and associated decreases in body weights were not observed in obese patients, the efficacy of liraglutide at 0.9 mg did not appear to be high. Rather, it appeared to be highly effective for patients who were non-obese and for whom amelioration of blood glucose elevations could be anticipated via the stimulation of insulin secretion. Therefore, we found that liraglutide at doses of 0.9 mg was highly effective in non-obese patients who were in the early stages of diabetes and was particularly effective in patients who had not yet been administered SU agents.

Pro12Ala substitution in peroxisome proliferator-activated receptor gamma 2 is associated with low adiponectin concentrations in young Japanese men.

Peroxisome proliferator-activated receptor gamma (PPAR gamma) has been shown to play an important role in adipocyte differentiation. A Pro12Ala substitution in PPAR gamma 2 has been reported to decrease receptor activity in vitro and to be associated with a decreased risk of type 2 diabetes in the general population. Recently, a PPAR response element (PPRE) was identified in the adiponectin promoter, suggesting that decreased PPAR gamma activity may lead to lower adiponectin levels. In the present study, serum adiponectin concentrations and the PPAR gamma Pro12Ala polymorphism were analyzed to determine whether this polymorphism is associated with lower serum adiponectin concentrations in young healthy Japanese subjects. Serum adiponectin concentrations were significantly lower in men with than in those without the Ala12 allele, whereas body mass index (BMI), homeostasis model assessment (HOMA)-beta, HOMA-IR, the insulin sensitivity index during oral glucose tolerance test (ISI [composite]), and serum leptin did not differ significantly between subjects with and without the Ala12 allele. Stepwise regression demonstrated BMI and the Ala12 allele to be independent predictors of serum adiponectin concentrations in men. In conclusion, the Pro12Ala substitution in PPAR gamma 2 may reduce serum adiponectin concentrations in young Japanese men.

Effect of cilnidipine on insulin sensitivity in patients with essential hypertension.

To clarify the effect of cilnidipine, a long-acting dihydropyridine Ca-antagonist that blocks both L- and N-type Ca(2+)-channels, on insulin sensitivity, cilnidipine at 5 to 10 mg/day was administered to ten patients with essential hypertension for 12 weeks. Mean age and body mass index (BMI) were 57.7 +/- 5.0 (SEM) years old and 27.1 +/- 1.5, respectively. Blood pressure, serum levels of catecholamines, glucose and lipid were determined before and after the treatment. Insulin sensitivity was also measured by a euglycemic hyperinsulinemic clamp method using an artificial pancreas (STG-22; Nikiso, Tokyo, Japan) before and after the treatment. Cilnidipine administration significantly lowered blood pressure from 154/96 to 137/84 mmHg (p<0.05). The glucose infusion rate was significantly increased by 20.8%, from 3.27 +/- 0.36 to 3.95 +/- 0.55 mg/kg/min (p<0.05). HbA1C and serum lipid levels such as total cholesterol and triglyceride were not altered. In addition, cilnidipine treatment did not significantly increase serum norepinephrine levels (278 +/- 25.2 vs. 332 +/- 33.6 pg/ml). Our results suggest that cilnidipine improves insulin sensitivity, possibly due to its exerting a vasodilatory action without stimulating sympathetic nervous activity.

A genome-wide association study for diabetic retinopathy in a Japanese population: potential association with a long intergenic non-coding RNA.

Elucidation of the genetic susceptibility factors for diabetic retinopathy (DR) is important to gain insight into the pathogenesis of DR, and may help to define genetic risk factors for this condition. In the present study, we conducted a three-stage genome-wide association study (GWAS) to identify DR susceptibility loci in Japanese patients, which comprised a total of 837 type 2 diabetes patients with DR (cases) and 1,149 without DR (controls). From the stage 1 genome-wide scan of 446 subjects (205 cases and 241 controls) on 614,216 SNPs, 249 SNPs were selected for the stage 2 replication in 623 subjects (335 cases and 288 controls). Eight SNPs were further followed up in a stage 3 study of 297 cases and 620 controls. The top signal from the present association analysis was rs9362054 in an intron of RP1-90L14.1 showing borderline genome-wide significance (Pmet = 1.4×10(-7), meta-analysis of stage 1 and stage 2, allele model). RP1-90L14.1 is a long intergenic non-coding RNA (lincRNA) adjacent to KIAA1009/QN1/CEP162 gene; CEP162 plays a critical role in ciliary transition zone formation before ciliogenesis. The present study raises the possibility that the dysregulation of ciliary-associated genes plays a role in susceptibility to DR.