Diabetes Research and Clinical Practice

Published by Elsevier
Print ISSN: 0168-8227
This study compares the efficacy of 0.01% rh-PDGF-BB with standard wound care in 20 patients with diabetes mellitus with neuropathic large plantar ulcers off-loaded with modified total contact cast. The incidence, duration and rate of healing were compared. An accelerated rate of healing in rhPDGF group was observed.
While evidenced-based guidelines promote glycated hemoglobin (HbA(1c)) targets <7.0% in order to reduce the long-term risk of diabetic complications, many individuals with type 2 diabetes do not achieve these targets. Fear of hypoglycemia provides a major barrier to improving blood glucose control as a result of delayed insulin initiation and failure to appropriately titrate insulin following initiation. Modern insulin analogs were designed to achieve improved blood glucose control with similar hypoglycemic risk compared with non-analog insulins (or similar blood glucose control with reduced hypoglycemic risk). While this has been demonstrated in randomized controlled trials, there is a need to confirm these findings in an everyday clinical setting. The A(1)chieve study will evaluate adverse events and effectiveness of premix (biphasic insulin aspart 30 [NovoMix 30]), basal (insulin detemir [Levemir]), and meal-time (insulin aspart [NovoRapid]) insulin analogs in people with type 2 diabetes in near-routine clinical practice. A(1)chieve is an international, prospective, multi-center, open-label, non-interventional, 24-week study of people with type 2 diabetes using an insulin analog. The study will recruit 60 000 people from 30 countries across four continents (Asia, Africa, South America, and Europe). The primary aim of the study is to assess the adverse event profile of the study insulins in routine clinical practice, including rates of hypoglycemia. In addition, effectiveness (HbA(1c), fasting plasma glucose, and postprandial plasma glucose) and patient quality of life outcomes will be measured. Comprehensive epidemiological data will be collected at baseline, including recent plasma glucose results and hypoglycemic episodes, prevalence of diabetes-related complications, and measures of current standards of care. Thus, A(1)chieve should provide important information about how insulin analogs perform in daily clinical practice.
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The aim of this study was to investigate association of a missense mutation in plasma PAF acetylhydrolase (G994T) with intima media thickness (IMT) of the carotid arteries. One hundred and forty Japanese type 2 diabetic patients aged from 40 to 79 years without severe nephropathy were enrolled in this study. The genotype of the patients was determined by allele specific PCR. IMT of the carotid arteries of the subjects was recorded by B-mode ultrasound imaging. The patients were divided into two groups by genotyping, one carrying two wild alleles (wild group), and another carrying one or two mutant alleles (mutant group). Each group was further divided into two subgroups according to age; one subgroup consisted of 40s or 50s, and another consisted of 60s or 70s. The prevalence of the G994T mutation in the subjects was 28.6% (24.3% heterozygote, and 4.3% homozygote). IMT of the elderly patients of the mutant group was significantly greater (0.98 +/- 0.22 mm, n = 26) than of the elderly patients of the wild group (0.87 +/- 0.20 mm, n = 50, P = 0.0292). There was no significant difference in clinical characteristics between the two subgroups. The results of this study indicate that the missense mutation in plasma PAF acetylhydrolase is associated with development of atherosclerosis in the elderly.
HLA is an important etiologic genetic factor in Type I diabetes and specific HLA-class II genes are closely related to the onset of the disease. Many differences in the patterns of susceptible and resistant DRB1, DQA1, and DQB1 genes have been observed among various ethnic groups. We have previously shown that DRB1*0405, DRB1*0901 and DQA1*0301-DQB1*0302 were the major susceptible alleles or haplotype to Type I diabetes while DR-DQ haplotype studies suggested the important role of DR and DQ alleles in susceptibility and resistance in Japanese patients. Based on the analysis of 90 Japanese patients with childhood onset Type I diabetes and 136 unrelated healthy Japanese controls by polymerase chain reaction-restriction fragment polymorphism method (PCR-RFLP), we report here the association of Type I diabetes with DPB1*0201 (relative risk = 2.29; Pc = 0.027) in this population. Comparison of linkage disequilibrium patterns between patients and controls showed that the significantly high prevalence of DPB1*0201 among patients cannot be attributed simply to linkage disequilibrium with susceptible DRB1 alleles and DQA1-DQB1 haplotypes. Our results suggest that in addition to alleles at the DRB1, DQA1, DQB1 loci, polymorphism at DPB1 locus also influences the risk of Type I diabetes.
Werner's syndrome is a rare inheritated disorder characterized by accelerated aging and is often accompanied by diabetes mellitus or impaired glucose tolerance. Previous reports suggest that insulin resistance is involved in the development of diabetes associated with Werner's syndrome. In the present study, CS-045((+/-)-5-[4-(6-Hydroxy-2,5,7,8-tetramethylchroman-2-ylmet hoxy)benzyl] - 2,4-thiazolidinedione, a new oral hypoglycemic agent which reportedly reduces insulin resistance, was administered to 2 Werner's syndrome patients. The patients were hospitalized for the duration of the study. During a pretreatment period lasting 8 weeks the patients received a controlled diet, however, their previous treatment was unchanged. Throughout the 4-week treatment period, each subject's blood glucose level was measured 7 times each day (07:30, 10:00, 11:30, 14:00, 17:30, 20:00, 22:00) for 1 week at 8, 4, and 1 week before treatment and at 2 and 4 weeks after treatment. To assess insulin action, the euglycemic glucose clamp technique was performed in these subjects at insulin infusion rates of 20, 120 and 400 mU/kg/min before and after 4 weeks of treatment. After 4 weeks of treatment with CS-045, the mean blood glucose level at each time point measured in this study was markedly lower compared to the corresponding pretreatment level.(ABSTRACT TRUNCATED AT 250 WORDS)
CS-045, (+/-)-5-[4-(6-hydroxy-2,5,7,8-tetramkethylchroman-2- ylmethoxy)benzyl]-2,4-thiazolidinedione, lowers plasma glucose in several animal models of non-insulin dependent diabetes mellitus (NIDDM) presumably by increasing insulin sensitivity. Little adverse effect was found in a phase 1 study on healthy male subjects. In order to test its efficacy in lowering plasma glucose in NIDDM in man, a pilot multi-center clinical trial of CS-045 was carried out in 146 patients with NIDDM whose glycemic control was inadequate (FPG greater than 140 mg/dl) on diet and/or other oral hypoglycemic agents. CS-045 was given orally in a daily dose of 200 mg or 400 mg for 12 weeks in addition to the previous treatment. The mean fasting plasma glucose (FPG) and fructosamine began to decrease within 2 weeks and the mean HbA1c within 8 weeks. After 12 weeks, the FPG fell from 192 +/- 41 to 155 +/- 45 mg/dl (P less than 0.01), fructosamine from 3.7 +/- 0.6 to 3.3 +/- 0.6 (P less than 0.01), and HbA1c from 8.9 +/- 1.5 to 8.1 +/- 1.5% (P less than 0.01). The drug was effective in 39% of patients in that FPG fell by more than 20% of the initial value. This rate of efficacy was the same when CS-045 was given alone or together with other oral hypoglycemic agents. The drug was more effective in a dosage of 400 mg than with 200 mg (the rate of efficacy 46% vs 25%) and more effective in obese patients than in lean patients (46% vs 25%).(ABSTRACT TRUNCATED AT 250 WORDS)
We assessed the effect of CS-045, a new hypoglycemic agent, on B-cell function in partially pancreatectomized rats. At the age of 4 weeks, male Wistar rats were subjected to 90% pancreatectomy (Px). For 2 weeks starting at 6 weeks after surgery the Px rats were treated with CS-045 (CS rats) mixed with chow pellets in a proportion of 0.2% (w/w). To compare the efficacy of CS-045 with that of insulin therapy, an osmotic pump was implanted to release insulin (1.2 units/day) into the intraperitoneal cavity of the Px rats (Is rats). Plasma glucose levels in the CS and Is rats were significantly lower than in the control Px rats; however, no marked improvement in plasma glucose or insulin levels was observed in glucose tolerance test (2 g/kg, i.p.) in the CS rats. Insulin secretion by the isolated perfused pancreas in response to 16.7 mM glucose showed a biphasic pattern, but was slightly reduced in the Px and CS rats compared with the Is rats. Insulin secretion induced by 19 mM arginine was unaffected by the treatment. The insulin content of the CS rats was significantly greater than in the Px and Is rats. Histological observations suggested regranulation of the pancreatic islets of the CS rats. B-cell areas within the islet were restored to normal levels in the Cs and Is rats. These findings indicate that the hypoglycemic effect of CS-045, which is not mediated by insulin secretion from the residual pancreas, prevents destruction of the islet.
We evaluated the effects of thromboxane synthetase inhibitor, OKY-046, on urinary albumin and prostaglandin (PG) excretion in 14 patients with non-insulin-dependent diabetes mellitus (NIDDM). Urinary excretion of 6-keto-PGF1 alpha (a stable metabolite of PGI2), TXB2 (a stable metabolite of TXA2) and PGE2 in NIDDM patients was comparable with that in control subjects. However, the urinary 6-keto-PGF1 alpha/TXB2 ratio in NIDDM patients with both micro- and macroalbuminuria was significantly (P less than 0.001) lower than that in the controls. By a single administration of OKY-046 (40 mg, i.v.) to the diabetic patients, urinary TXB2 excretion significantly (P less than 0.05) decreased from 169.7 +/- 23.9 to 140.2 +/- 17.9 ng/gCr, but urinary 6-keto-PGF1 alpha and PGE2 excretion did not change significantly. The urinary 6-keto-PGF1 alpha/TXB2 ratio thus significantly (P less than 0.01) increased from 1.02 +/- 0.13 to 1.73 +/- 0.41 as associated with significant increments in urine volume (P less than 0.05), urinary sodium excretion (P less than 0.01) and creatinine clearance (P less than 0.05). Of 14 diabetic patients, 7 with macroalbuminuria (albumin index exceeding 100 mg/gCr) were orally given OKY-046 (600 mg/day) for 8 weeks. After this period, the urinary albumin index significantly (P less than 0.05) decreased from 524.9 +/- 149.6 to 317.6 +/- 90.6 mg/gCr.(ABSTRACT TRUNCATED AT 250 WORDS)
To investigate the differences of Toll-like receptors (TLRs) expression and response of monocyte and modulation of 1,25-dihydroxy-vitamin D3 on monocyte activity. Peripheral blood monocytes were collected from 23 healthy controls, 18 latent autoimmune diabetes in adults (LADA), and 22 type 2 diabetes mellitus (T2DM), respectively. CD14, TLR2 and TLR4 expression were analyzed. Moreover, the effect of 1,25-dihydroxy-vitamin D3 (1,25(OH)(2)D3) on monocyte response to lipoteichoic acid (LTA) and lipopolysaccharide (LPS) was evaluated in vitro by measuring phosphorylation level of NF-kappaB-p65 and associated cytokine production. Monocytes showed significantly higher surface CD14 expression from LADA compared with that from T2DM and controls, and high expression of TLR4 from LADA and T2DM than controls. After incubation with LPS or LTA, decreased surface expressions of CD14 were observed on monocytes from T2DM and controls, in contrast to the increased on monocytes from LADA. Activation of NF-kappaB and amounts of IL-1beta and TNF-alpha production by stimulation with ligands significantly increased in LADA and T2DM, which was modulated by 1,25(OH)(2)D3 to similar level, as compared to controls. The modulation of 1,25(OH)(2)D3 on monocytes makes us to consider more potency of vitamin D3 as therapy in LADA and T2DM.
The exact factors contributing to the pathogenesis of type 2 diabetes remain elusive. Lately, it was suggested that inflammation and activation of the innate immune system could be linked to type 2 diabetes pathogenesis and also to the development of common diabetic complications, mainly atherosclerosis. The aim of this study was to investigate the role of monocytes in this sub-clinical inflammatory state and test 1,25-dihydroxyvitamin D(3), the active form of Vitamin D, as an anti-inflammatory agent. For this purpose, monocytes from type 2 diabetic patients were compared to monocytes from healthy controls and type 1 diabetic patients. The expression profile of inflammatory markers in freshly isolated and immune-stimulated monocytes was measured by quantitative real-time RT-PCR. Type 2 diabetic patients showed significantly higher expression levels of TNF-alpha, IL-6, IL-1, IL-8, COX-2, ICAM-1 and B7-1 compared to controls and type 1 diabetic patients. 1,25-Dihydroxyvitamin D(3) was able to down-regulate the expression of TNF-alpha, IL-6, IL-1, and IL-8, confirming its immunomodulatory properties. From these data we concluded that monocytes from type 2 diabetic patients have a pro-inflammatory profile. In addition, 1,25-dihydroxyvitamin D(3) was able to modulate inflammation in these monocytes.
To investigate the relationship between Erythropoietin (EPO) and 1,25-dihydroxyvitamin D levels, and tubular damage in patients with diabetes mellitus (DM) without persistent microalbuminuria. We measured serum EPO and 1,25-dihydroxyvitamin D levels and tubular injury markers such as urinary N-acetyl-beta-d-glucosaminidase (NAG) and retinol binding protein (RBP) levels in 41 non-diabetic controls, 40 patients with Type 1 and 40 with Type 2 DM. Median serum EPO levels were lower in Type 1 (2.57 mIU/ml: p<0.001) and Type 2 DM (5.69 mIU/ml: p=0.044) than in controls (8.76 mIU/ml), though haemoglobin levels did not differ. Median 1,25-dihydroxyvitamin D levels were lower in Type 1 (41.0 pmol/l: p=0.001) and Type 2 DM (41.8 pmol/l: p=0.035) than in controls (56.1 pmol/l), though serum creatinine, calcium, phosphate and PTH levels did not differ. Median RBP excretion was higher in Type 2 DM (0.35 mg/l vs. 0.23 mg/l: p=0.013) than in controls. Median NAG excretion was higher in Type 1 DM (1,079 micromol/h vs.1,030 micromol/h: p=0.048) compared to controls. Tubulo-interstitial damage with low levels of EPO and 1,25-dihydroxyvitamin D occurs early in Type 1 and Type 2 DM before persistent microalbuminuria.
Aims: To define whether 1,25-dihydroxy vitamin D3 (1,25-(OH)₂ D₃) can protect diabetic retinopathy and to investigate its impact on the expressions of vascular endothelial growth factor (VEGF) and transforming growth factor-β₁ (TGF-β₁) in the retinas of rats with diabetes. Methods: Male Sprague-Dawley (SD) rats were divided into normal control group, 1,25-(OH)₂ D₃ group and diabetes group. The rats in 1,25-(OH)₂ D₃ group and diabetes group were established to type 2 diabetes model with high-fat and high-sugar diet and streptozotocin (STZ). Meanwhile, the rats of 1,25-(OH)₂ D₃ group were treated with 1,25-(OH)₂ D₃. After 13 weeks, morphological changes of retinal tissues were observed under microscopes after hematoxylin-eosin staining. VEGF and TGF-β₁ expressions in the retinal tissues were detected with immunohistochemistry staining. Results: Pathological examination showed an appearance of edema and disordered arrangement of retinal tissues in diabetes group, but milder pathological changes in 1,25-(OH)₂ D₃ group. VEGF and TGF-β₁ expressions of both diabetes group and 1,25-(OH)₂ D₃ group significantly increased (P<0.05), but those of 1,25-(OH)₂ D₃ group were significantly lower than diabetes group (P<0.05). Conclusion: 1,25-(OH)₂ D₃ had partially protective effect on diabetic retinopathy of diabetic rats, the mechanism of which might inhibit VEGF and TGF-β₁ expressions in the retinal tissues.
– Questionnaires on eating habits and answers to them by study subjects. 
– Effect of habitual intake of dairy products on makers of glycemic control. 
1,5-Anhydroglucitol (1,5-AG), a marker of glycemic control state, is reabsorbed via SGLT (sodium glucose cotransporter)-4 (SLC5A9) at renal proximal tubules. SGLT4 is responsible for reabsorption of mannose, fructose, galactose, glucose, and 1,5-AG. Thus, based on our hypothesis that serum 1,5-AG levels are influenced by diet, we investigated whether eating habits influence serum 1,5-AG levels. In total, 330 subjects (158 males and 172 females) with normal glucose tolerance participated. Relationships between serum 1,5-AG levels and eating habits (intake of meats, fish, soybean products, eggs, dairy products, fruit, vegetables, and salt) surveyed by questionnaire were investigated. Stepwise multivariate regression analysis revealed that habitual intake of dairy products was a significant negative explanatory variable for serum 1,5-AG levels. Serum 1,5-AG levels were lower in subjects with habitual intake of dairy products than in those without. On the other hand, HbA(1C), glycated albumin, fasting plasma glucose, and OGTT 2-h plasma glucose were not different between the subjects of these two groups. In conclusion, habitual intake of dairy products was associated with low serum 1,5-AG levels, independently of plasma glucose levels.
An assay of plasma 1,5-anhydroglucitol was evaluated. Assay CVs, effects of four plasma freeze-thaw cycles, glucose up to 80 mmol/L and triglycerides up to 20 mmol/L were acceptable. 1,5-anhydroglucitol levels were significantly lower in diabetic vs. non-diabetic subjects and correlated inversely with renal function, but not with HbA1c.
Endpoint HbA(1c) <7.0% was achieved by 80 (73.4%) lispro mix 25 (LM25)-treated patients and 67 (60.9%) glargine-treated patients (p=0.027) with baseline 1,5 anhydroglucitol (1,5AG) below median and 75 (70.8%) LM25-treated patients and 72 (63.7%) glargine-treated patients (p=0.238) with 1,5AG≥median, suggesting, 1,5AG may offer therapeutic insight when starting insulin therapy.
A new method was developed for quantitating the serum and urinary levels of 1,5-anhydroglucitol (AG), a sensitive and informative marker of glycemic control. This method utilized a combination of ODS and pyranose oxidase-immobilized columns for HPLC, and monitored hydrogen peroxide production with an electrochemical detector. We applied this method to determine the serum and urinary AG levels in 15 patients with insulin-dependent diabetes mellitus (IDDM) as well as in control subjects. Baseline separation of AG from other sugars such as glucose and myoinositol was achieved. Quantitation of AG was achieved over the range from 0.2 ng to 0.3 micrograms based upon peak heights. The serum and urinary AG levels in the IDDM patients were 4.4 +/- 8.3 mg/l and 5.1 +/- 4.3 mg/day, respectively. We found that the urinary AG to serum AG ratio showed a linear correlation with the urinary glucose level in the IDDM patients (urinary glucose (y) vs. urinary AG to serum AG ratio (x): y = 9.071x-0.991; r = 0.968, P < 0.001). This method proved efficient and reliable for quantitating urinary AG. Since determination of both the AG and glucose levels in urine gives equivalent clinical information to the serum AG level, urinary monitoring could provide a valuable addition to the available methods for assessing the glycemic status of IDDM patients.
Since normal reference values change with age in some clinical parameters, we measured the plasma levels of 1,5-anhydroglucitol (AG), a new marker of glycemic control in diabetes mellitus, in healthy subjects and in rats. Our results showed a significantly negative correlation of the marker with age in humans and that the plasma AG levels of older rats were markedly lower than those of younger counterparts. This remarkable reduction of AG in the older rat group can be partially explained by our finding that aged animals excreted AG more rapidly in the urine than younger ones, besides a decrease in food intake. We therefore suggest that normal clinical reference values for plasma AG levels should be modified according to age.
To examine the serum 1,5-anhydroglucitol (AG) levels as a surrogate measure of postprandial hyperglycemia (PPH) and insulin secretion in a wide range of hyperglycemia, we compared the relationship between the glycemic index during a 75g oral glucose tolerance test (OGTT) and the insulinogenic index and 1,5-AG according the overall glycemic state. Fasting serum 1,5-AG levels were lower in the type 2 diabetic group (18.0+/-7.0microg/mL) than in the normal glucose tolerance (NGT, 25.4+/-4.0microg/mL), impaired fasting glucose (IFG, 24.6+/-6.2microg/mL), and impaired glucose tolerance (IGT, 22.1+/-6.2microg/mL) groups and were clearly correlated with glycemic values from the OGTT. 120-min post-challenge plasma glucose (PPG(120)) emerged as an independent predictor for 1,5-AG levels after multiple linear regression analysis (beta=-0.554, P<0.001). Additionally, 1,5-AG levels were significantly correlated with PPG(120) in each quartile of A1C, and the coefficients increased with higher A1C quartiles. Subjects with low 1,5-AG levels had both increased insulin resistance and decreased insulin secretion. Decreased 1,5-AG levels are closely correlated with PPH and decreased insulin secretion capacity across a wide range of glycemia, even in relatively well-controlled diabetes.
The serum concentration of 1,5-anhydroglucitol (1,5-AG), a polyol which originates mainly in the diet, is used in Japan as a new marker for glycemia. To evaluate the potential interference of 1, 5-AG measurements by traditional Chinese medicines (Kampo), we examined the 1,5-AG content in 32 types of concentrated dosage forms of Kampo using high performance liquid chromatography (HPLC). The 32 types of Kampo were the most frequently used in Japan, two of which, Ninjin-yoei-to (7030 microg/g dry weight) and Kami-kihi-to (6700 microg/g dry weight), contained large amounts of 1,5-AG. Six others contained small amounts of 1,5-AG. Both Ninjin-yoei-to and Kami-kihi-to contain the same ingredient, Polygalae radix, which is a crude form of polygalitol (1,5-AG). To confirm the effects of these Kampo medicines on the serum levels of 1,5-AG, we administered Ninjin-yoei-to (7.5 g/day) for 8 weeks to 18 patients with Type 2 diabetes mellitus (Type 2 DM). The serum level of 1,5-AG increased from 9.8+/-8.9 to 28.1+/-17.5 microg/ml by week 8. Hemoglobin A1c (HbA1c) had not changed by week 8. Thus, an abnormal serum 1,5-AG level may be present in patients taking Kampo which contains Polygalae radix.
1,5-Anhydroglucitol (1.5-AG) is known to closely reflect diabetic control within several days. The possibility of predicting long-term glycemic control after an educational hospitalization of type II diabetic patients was investigated by examining the relationship between changes in serum 1,5-AG levels after a short-term trial home stay following an educational program and long-term changes in glycosylated hemoglobin A1c (HbA1c) levels after discharge. After 22 patients with type II diabetes had successfully completed the educational hospitalization program, they returned as outpatients for 5 nights in a row. Changes in serum 1,5-AG levels were determined during this period. The HbA1c levels were then determined over a period of 3 months after discharge, and the relationship between changes in 1,5-AG and HbA1c levels was examined. Changes in serum 1,5-AG levels during the 5-day trial home stay and the changes in HbA1c levels during the 3 months after discharge from the hospital were found to be significantly correlated (r = 0.70, P < 0.01). A comparison of the decreased group, which exhibited a decrease in 1.5-AG levels of 5.0 mumol/l or more during the trial home stay, and the unchanged group, revealed that increases in body mass index 3 months after discharge were significantly higher in the decreased group (1.2 +/- 0.4%) than in the unchanged group (0.2 +/- 0.5%) (P < 0.05). Determination of serum 1,5-AG levels of patients with type II diabetes before and after a trial home stay following educational hospitalization was found to be useful in identifying patients at high risk of recurrence of poor glycemic control in the future.
We review the use of 1,5-anhydroglucitol (1,5 AG) in diagnosing and monitoring patients with diabetes. This six-carbon chain monosaccharide is one of the major polyols present in humans. Its concentration in serum is normally about 12 to 40 micrograms/ml. This substance is derived mainly from food, is well absorbed in the intestine, and is distributed to all organs and tissues. It is metabolically stable, being excreted in the urine when its level exceeds the renal threshold. It is reabsorbed in the renal tubules, and is competitively inhibited by glucosuria, which leads to a reduction in its level in serum. The correlation between this reduction and the amount of glucose present in urine is so close that 1,5 AG can be used as a sensitive, day-to-day, real-time marker of glycemic control. It provides useful information on current glycemic control and is superior to both HbA1c and fructosamine in detecting near-normoglycemia.
The preventive effect of an immunopotentiator, beta-1,6;1,3 D-glucan, on the development of diabetes and insulitis was studied in BB rats. The intravenous administration of 1 mg kg-1 week-1 of beta-1,6;1,3 D-glucan from the age of 4 weeks decreased the cumulative incidence of diabetes from 43.3% (13/30) to 6.7% (2/30) (P less than 0.005) and also the incidence of insulitis from 82.4% (14/17) to 26.3% (5/19) at the age of 20 weeks (P less than 0.002). Eight of nine rats were free from diabetes for 5 weeks after stopping beta-1,6;1,3 D-glucan at the age of 20 weeks. The total numbers of leukocytes in the peripheral blood and spleen of the rats were increased by beta-1,6;1,3 D-glucan treatment (P less than 0.05), whereas their T lymphocytes subsets were not changed. These data indicate that immunopotentiators could modulate the autoimmune mechanisms directed to pancreatic islets and inhibit the development of diabetes in BB rats.
Sulphonylureas are effective and well tolerated in patients with Type 2 diabetes, but may be associated with weight gain, and lack of compliance due to multiple daily dosing. This open, uncontrolled surveillance study examined the efficacy and safety of glimepiride, a new sulphonylurea, administered once daily in patients with Type 2 diabetes. A total of 1,770 patients were enrolled in the study, and 284 patients were selected for follow-up. Patients received 0.5 to >4 mg glimepiride once daily for 1.5 years. HbA(1c) was reduced from 8.4% at baseline to 7.1% after 4 months and 6.9% after 1 and 1.5 years (median intra-individual change from baseline: -1.4, -1.5, and -1.7%, respectively; P<0.0001). Treatment with glimepiride also resulted in significant and stable weight loss relative to baseline, with the exception of patients with a body mass index of <25 kg/m(2). Mean body weight was reduced from 79.8 kg at baseline to 77.9 kg after 4 months, 77.2 kg after 1 year, and 76.9 kg after 1.5 years (mean intra-individual change from baseline: -1.9 kg, P<0.0001; -2.9 kg, P<0.05; -3.0 kg, P<0.005, respectively). Therefore, once daily glimepiride provides effective glycaemic control, and may have advantages over other sulphonylureas, because it exhibits weight neutralizing/reducing effects in patients with Type 2 diabetes.
Islet cell antibodies (ICA), insulin autoantibodies (IAA) and islet cell surface antibodies (ICSA) together with C-peptide were determined in 1031 healthy schoolchildren to evaluate the frequency of autoimmune reactions towards endocrine pancreas and its relation to insulin secretion in non-diabetic children. The prevalence of ICA (levels > 6 JDF units) was 1.4% (14/1012) while 44 children (4.3%) were ICSA-positive and 40 (4%) had IAA. Girls had higher titres of ICSA than boys. Young children (7-8 years) more often had IAA than 12-13-year-old children who, however, had ICA three times more often than the young children. There were no clear associations between the different antibodies. Of the children, 2.4% had very low post-prandial serum C-peptide values (< or = 0.25 nmol/l). Serum C-peptide was higher in girls than in boys (P < 0.001) and in older children than in younger (P < 0.001). Girls with low levels of ICA had high C-peptide values, while girls with high ICA titers had low C-peptide values, the latter perhaps indicating partial beta cell loss. IAA and ICSA were not related to C-peptide values but both positive ICSA and high C-peptide values were most common in the autumn (P < 0.02 and P < 0.0001, respectively). One of the ICA-positive children developed diabetes in 1991, 4 years after the blood sample was taken. Since after 5 years only one of the children has developed IDDM, it can be concluded autoimmune reactions towards endocrine pancreas and insulin may occur in many children without the development of manifest diabetes. Those with high ICA titers may have lost so many beta cells that their insulin secretion is affected, which in some cases might lead to diabetes many years later.
To study the C(-106)T polymorphism in the promoter of the aldose reductase (ALR2) gene: (a) its local prevalence and (b) its modulation of the susceptibility for developing retinopathy. DNAs of 96 control subjects and 53 long-standing (duration 17.9+/-5.4 years) type-2 diabetic patients were analyzed by PCR-RFLP with BfaI enzyme. Retinopathy was graded with 2-eye, 7-field fundus color photography. The IMF-HbA1c was the arithmetic mean of all HbA1c's of each patient. The genotypes in the controls were CC=57 (59.4%), CT=32 (33.3%) and TT=7 (7.3%), with Hardy-Weinberg chi(2)=0.793 (p>0.50). Among 53 diabetics, CC=24 (45.3%), CT=26 (49.0%) and TT=3 (5.7%). The correlation between IMF-HbA1c and retinopathy progression rate was significant on CC (r=0.6102, p=0.0072) but not in CT+TT genotypes (r=0.26, p=0.1811). In Chilean adults, the frequency of the C(-106)T polymorphism of the ALR2 gene was similar to that reported by others. Type-2 diabetics with the CC genotype were more susceptible for developing retinopathy as a result of chronic hyperglycemia than those with the CT or TT genotype.
It is likely that the C allele of the polymorphism at position -106 in the promoter of aldose reductase gene, which codes a rate-limiting enzyme of the polyol pathway, is a susceptibility allele for diabetic retinopathy in Japanese type 2 diabetic patients.
To predict microalbuminuria easily in the diabetic outpatient clinic, we determined the range of albumin concentrations in the single-void first morning urine in 1090 healthy subjects of age 6-11 by the modified turbidimetry immunoassay (TIA) method, which uses 96-well microplates and a microplate reader to perform the assay quickly and conveniently. As the correlation coefficient of albumin concentration by the TIA uncorrected for creatinine versus corrected for creatinine was r = 0.79 (P less than 0.005), the values uncorrected for creatinine were used. When the distribution of values from 1090 healthy young children was simulated by using the chi-square test (k = 1), the 95% confidence interval was 0-18 micrograms/ml.
We have determined 11-beta-Hydroxysteroid Dehydrogenase Type 1 (HSD11B1) and Hexose-6-Phosphate Dehydrogenase (H6PD) mRNA expression levels in adipose tissues from patients with type 2 diabetes mellitus. Six non-diabetic and seven diabetic male patients who undergo elective abdominal surgery were included in the study and visceral and subcutaneous adipose tissue samples were obtained. Fresh preadipocyte cultures were administered to low and high glucose medium (11M and 25M) in vitro for 24h and mRNA extractions were performed. HSD11B1 and H6PD gene mRNA expression levels were determined by real-time PCR and compared. Glyceraldehyde-3-phosphate Dehydrogenase (G3PD) mRNA level is used as housekeeping gene expression. HSD11B1 mRNA levels were significantly higher in patient with T2DM than controls in both visceral and subcutaneous adipose tissues (3.35+/-0.7 vs. 0.37+/-0.1; P=0.01 and 2.07+/-0.8 vs. 0.11+/-0.05; P=0.01, respectively). H6PD mRNA levels were also significantly higher in patient with T2DM than controls in both visceral and subcutaneous adipose tissues (3.95+/-1.2 vs. 1.95+/-0.8; P=0.050 and 2.23+/-1.1 vs. 0.46+/-0.1; P=0.043, respectively). Failure to down-regulate HSD11B1 activity in patients with type 2 diabetes may contribute to the pathogenesis of T2DM. Subcutaneous and visceral adipose tissues similarly exhibit the same variation in patients with type 2 diabetes mellitus.
To evaluate glycemic control using convenience-oriented biphasic insulin analog compared with intensified insulin therapy, we conducted a 6-month multicentric, open-label, randomized trial in Japanese insulin-naive patients with type 2 diabetes mellitus. A total of 160 adult patients at 19 centers were randomized into two groups: those who received twice-daily injections of biphasic insulin aspart 30 and those on three-times-daily injections of insulin aspart with or without NPH insulin (multiple daily injections). At 6 months, mean HbA(1c) decreased by approximately 2.5% in both groups. Reduction of HbA(1c) on both regimens was better in patients whose prior therapy before starting the study was only diet and exercise (-5.0%) than in patients who were previously taking oral antidiabetic agents (-1.0%). No incidence of major hypoglycemia was observed in either regimen. These results suggest that convenience-oriented insulin therapy using biphasic insulin analog is as useful as intensified insulin therapy with insulin analog for the treatment of type 2 diabetes mellitus over 6 months. Furthermore, early induction of insulin therapy in individuals hitherto using only diet and exercise may provide good glycemic control. This study suggests that convenience-oriented biphasic insulin aspart 30 might be a useful option for the treatment of type 2 diabetes mellitus, especially for insulin-naive patients over 6 months, although it should be changed to another regimen when expected efficacy is not obtained.
Cultured cells derived from hamster insulinoma (In-111 R1 cells) were placed in 1.4 M dimethyl sulfoxide (Me2SO)-containing RPMI 1640 at 20 degrees C for 20 min. They were frozen to -40 degrees C at a cooling rate of 1.0 or 0.5 degrees C/min, subsequently to -80 degrees C at 3 degrees C/min with a programmable freezer. After being maintained at -80 degrees C, they were rapidly thawed to 37 degrees C. Thawed cells were washed with 0.75 M sucrose for removal of Me2SO. Recovered cells were cultured in 2 ml of RPMI 1640 with 1.3 mM theophylline under a gas phase of 95% air -5% CO2 at 37 degrees C for 2 days. In both cooling rates, frozen-thawed cells discharged more insulin than the thawed in the absence of theophylline. However, this released insulin level was higher in the cells frozen at a cooling rate of 0.5 degrees C/min than that at 1.0 degrees C/min. Moreover, insulin released from frozen-thawed hamster insulinoma cells increased significantly with the addition of 1.3 mM theophylline. Considering that the higher insulin release level at 11.1 mM glucose alone might indicate cellular damage, it is suggested that the cooling rate of 1 degree C/min may be better for cryopreservation of the dispersed cells under the present protocol for the assessment of the function of insulin release.
The PTPN22 is a negative regulator of the T cell response. Its +1858C>T (R620W) polymorphism has been shown to associate with a risk for multiple autoimmune diseases, including type 1 diabetes (T1D) and juvenile idiopathic arthritis (JIA). The minor (susceptibility) allele is absent in Asian populations, but a recent study suggested an independent involvement of another polymorphism located within the promoter -1123 nucleotides relative to the translational start site. We aimed to analyse the association of three PTPN22 polymorphisms in two distinct Caucasian populations, the Czechs (with T1D and with JIA) and Azeri (with T1D). The single nucleotide polymorphisms (SNP) at positions -1123 (rs2488457), +1858 (rs2476601, the R620W substitution), and +2740 (rs1217412) were genotyped using TaqMan assays in 372 subjects with childhood-onset T1D, 130 subjects with JIA, and 400 control subjects of Czech origin, and in 160 subjects with T1D and 271 healthy controls of Azeri origin. In the Czechs, all three SNPs were in a tight linkage disequlibrium, while in the Azeri, the linkage disequlibrium was limited to between the promoter and 3'-UTR polymorphism, D'(-1123, +2740)=0.99, r(2)=0.72. Haplotype reconstruction via the expectation-maximization algorithm showed in both populations that only the haplotype containing the minor (W) allele at codon 620 was associated with T1D (OR=2.26, 95% CI 1.68-3.02 in Czechs, OR=14.8, 95% CI 2.0-651 in Azeri) or JIA (OR=2.43, 95% CI 1.66-3.56 in Czechs). The haplotypes having the wild-type (R) allele at codon 620 and minor alleles at -1123 and/or +2740 were neutral as to the risk of autoimmune conditions in both populations. In two different Caucasian populations, the Czechs and the Azeri, no independent contribution can be detected either of the -1123 promoter SNP or the +2740 3'-UTR SNP, and only the minor allele at PTPN22 codon 620 contributes to the risk of autoimmunity.
A meta-analysis was conducted to evaluate the association of PTPN22 gene (+1858C/T -1123G/C) polymorphism with T1DM susceptibility. Electronic databases were used to identify published studies before September 2011. We adopted the most appropriate genetic model. The combined odds ratio (OR) with 95% confidence interval (95% CI) was calculated to estimate the strength of the association in a fixed or random effect model. Heterogeneity and publication bias were also assessed. Totally, 25 case-control studies including 8613 T1DM cases and 10,133 healthy controls (24 studies containing 8129 cases and 9641 controls for PTPN22 +1858C/T, 5 studies including 1460 cases and 1609 controls for PTPN22 -1123G/C) were identified as eligible and analyzed. The most appropriate co-dominant model was adopted. A significant association of PTPN22 +1858C/T gene polymorphism was found in overall population. When stratified by race, significance was observed in Europe and America, but not in Asia. We did not detect any association for PTPN22 -1123G/C polymorphism. Our study indicated that T1DM is associated with PTPN22 +1858C/T gene polymorphism, and targeting this promoter polymorphism should be dependent on ethnicity. Whether -1123G/C polymorphism is a susceptibility locus for T1DM, further studies with well-designed among different ethnicity populations are required.
In order to explore the different genetic backgrounds of non-obese and obese type 2 diabetes, we tried to genotype six SNPs (-11391G/A, -11377C/G, -10068G/A, G54V, Y111H and 4545G/C) in the adipose most abundant gene transcript-1 (APM1) gene in 338 type 2 diabetes (T2D) patients and 460 non-diabetic subjects by PCR-RFLP. Among these mutations, the 4545G/C mutation (rs1063539) contributed to the genetic risk of T2D in the non-obese group (OR=2.34, 95%CI: 1.31-4.21, P=0.004), and 57% of the risk is related to this polymorphism. On the contrary, -11377C/G (rs266729) was associated with type 2 diabetes in the obese group only (OR=2.45, 95%CI: 1.13-5.31, P=0.02), and 59% risk of diabesity could be attributed to that. All the associations above were adjusted for age and gender in unconditional logistic regression. Besides, the -11377G/4545C haplotype was merely related to obese diabetes (OR=2.12, 95%CI: 1.08-4.14, P=0.03). In addition, the obese diabetic group had significantly higher levels of triglyceride and insulin, better beta-cell function but lower glucose levels than the non-obese group (all P values <0.01). This study suggests that the genetic susceptibility is different between type 2 diabetes with and without obesity in Chinese Han population.
11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1), one of the isoforms of the 11beta-hydroxysteroid dehydrogenase enzymes, acts as an oxo-reductase to reactivate cortisone to cortisol, plays a critical role in tissue-specific corticosteroid reactions, and is therefore a key molecule associated with the development of metabolic syndrome. We investigated whether variations in the 11beta-HSD1 gene correlated with metabolic syndrome. We performed case-control study using a population-based urban Japanese cohort. Among 3005 urban residents, we examined 431 subjects diagnosed with metabolic syndrome according to the Japanese definition and 777 subjects with none of metabolic syndrome criteria as control. We genotyped three single nucleotide polymorphisms (SNPs) (+9410T>A, +17925C>T, +27447G>C) across the 11beta-HSD1 gene in them and analyzed the associations of SNPs and haplotypes with metabolic syndrome. The +9410A allele showed a tendency to metabolic syndrome (OR=1.5, 95%C.I., 1.0-2.2; P=0.041 and Bonferroni corrected P=0.123) without statistical significance. However, we could not find any significant association between metabolic syndrome and SNPs in the 11beta-HSD1 gene. Our findings indicate that polymorphisms and haplotypes in the 11beta-HSD1 gene are not significantly associated with metabolic syndrome in the Japanese population.
Aims: 11β-Hydroxysteroid dehydrogenase type 1 (HSD11B1), which converts inactive glucocorticoid to active glucocorticoid, plays a critical role in pathogenesis of non-alcoholic fatty liver disease (NAFLD). Serum alanine aminotransferase (ALT), an indicator of hepatocellular injury, has been suggested as a surrogate marker for NAFLD. To date, no study has specifically examined the relationship between HSD11B1 gene polymorphisms and ALT. Methods: A study was conducted to examine the association of common single nucleotide polymorphisms (SNPs) in HSD11B1 (rs12086634, rs1000283) with serum ALT level in 756 Korean subjects (348 males and 408 females). ALT values were divided into two groups: elevated (>33U/l in males, >25U/l in females) and normal. Results: SNPs showed a significant association with elevated ALT. According to results of logistic regression analysis adjusted for confounding variables, the GT+GG genotype for rs12086634 and the GA+AA genotype for rs1000283 showed significantly higher frequencies of elevated ALT, compared with the TT and GG genotypes, respectively (GT/GG vs. TT; OR 1.685, 95% CI 1.175-2.416, P=0.005, GA/AA vs. GG; OR 2.057, 95% CI 1.401-3.020, P<0.001, respectively). Conclusions: HSD11B1 polymorphisms (rs12086634 and rs1000283) are associated with elevated levels of ALT. Findings from this study suggest a possible association between HSD11B1 polymorphisms and hepatocellular injury, such as that seen in patients with NAFLD.
AST-120, an oral adsorbent currently on-label only in Asian countries with phase III trials ongoing in the US, slows renal disease progression in patients with diabetes and advanced-stage chronic kidney disease (CKD). The objective of this study is to evaluate the cost-effectiveness of using AST-120 to treat patients with type 2 diabetes and advanced-stage CKD. We used Markov model simulating the progression of diabetic nephropathy. Data were obtained from randomized trials estimating the progression of diabetic nephropathy with and without AST-120, and published literature. The base population was patients 60 years of age with type 2 diabetes and Stages 3 and 4 CKD. Treating patients with diabetes and advanced-stage CKD was found to be a dominant strategy, and quality of life improved further and more money was saved (0.22 quality-adjusted life years [QALYs] and $15,019 per patient) using AST-120 than the control strategy. Sensitivity analysis results were robust with regard to cost, adherence, and quality of life associated with AST-120 therapy, as well as age at diagnosis. The model was relatively sensitive to the effectiveness of AST-120. Treating patients with type 2 diabetes and advanced-stage CKD with AST-120 appears to extend life and reduce costs.
There is little clinical evidence when AST-120 should be prescribed for subjects with early stage overt diabetic nephropathy. We therefore designed a prospective, randomized, controlled study for subjects with type 2 diabetes (serum creatinine <1.5mg/dl and urinary protein >0.5g/day) in November, 2001. The primary end point was defined as exceeding 2mg/dl of serum creatinine, and the secondary end point was defined as introducing a hemodialysis. Twenty-two subjects were selected, and after excluding 6 drop-out subjects, 16 subjects (10 in the control group; 6 in the KRM group) finally entered the study. Mean follow-up periods were 37 and 34 months in the control and KRM groups, respectively. There was no difference in clinical characteristics including renal dysfunction at baseline between the two groups. There was a significant reduction in urinary indoxyl sulfate at month 12 in the KRM group than in the control group. A significant difference was observed in changes in mean levels of serum creatinine versus time between the two groups. The primary end points were counted in 7 (70%) of the control subjects, while only 1 (17%) of the KRM group, and the Kaplan-Meier analysis was statistically significant. Although 4 (40%) of the control group and 1 (17%) of the KRM group were initiated hemodialysis as the secondary end point, the difference did not reach a statistical significance. Thus, we concluded that administration of AST-120 initiated in early stage overt diabetic nephropathy stunts the progression of renal dysfunction.
We studied the effect of a novel dipeptidyl peptidase IV (DPP IV) inhibitor, DA-1229, on blood glucose profile and pancreatic β-cell mass in established diabetes after streptozotocin (STZ) treatment. Mice that developed diabetes after administration of STZ 100mg/kg were treated with DA-1229 for 13 weeks. DA-1229 significantly reduced plasma DPP IV activity, and enhanced glucagon-like peptide 1 (GLP-1) levels. In STZ-treated mice fed DA-1229 (STZ-DA), blood glucose levels were significantly lower than those in diabetic mice fed normal chow (STZ-NC). Basal and glucose-stimulated insulin secretion and glucose tolerance assessed by intraperitoneal glucose tolerance test were significantly improved by DA-1229 administration. Volume density of β-cell was significantly increased in STZ-DA mice compared to STZ-NC mice, suggesting that DA-1229-mediated amelioration of established diabetes was due to beneficial effect of DA-1229 on β-cell mass. The number of replicating β-cells and that of scattered small β-cell unit representing β-cell neogenesis were significantly increased in STZ-DA mice compared to STZ-NC mice, explaining increased β-cell mass by DA-1229. The expression of PDX-1, a downstream mediator of GLP-1 action, was increased in islets of STZ-DA mice compared to STZ-NC mice. These results suggest a therapeutic potential of DA-1229 in diabetes, particularly that associated with decreased β-cell mass.
The effects of a novel hypoglycemic agent, calcium(2s)-2-benzyl-3-(cis-hexahydro-2-isoindolinylcarbonyl) propionate dihydrate (KAD-1229), which is a benzyl succinate derivative, on liver metabolism were investigated using isolated hepatocytes from normal rats. In the presence of 10 mM glucose, KAD-1229 increased the L-lactate production (41.1 +/- 0.9 versus 60.9 +/- 2.6 mumol of lactate/g of cells/30 min; P < 0.05) and inhibited gluconeogenesis in hepatocytes (0.94 +/- 0.02 versus 0.70 +/- 0.03 mumol of [2-14C]-pyruvate converted to glucose/g of cells/20 min; P < 0.05). These effects by KAD-1229 were accompanied by an increase in the cellular content of fructose-2,6-bisphosphate (F-2,6-P2), which is one of the important regulators of hepatic glucose metabolism, in a dose-dependent manner (0.05-2.5 mM). KAD-1229 also stimulated the oxidation of [2-14C]-pyruvate and [6-14C]-glucose in the tricarboxylic acid cycle (+18 and +31%, respectively), indicating that stimulation of tricarboxylic acid cycle activity and/or enhancement of the glycolytic flux rate had occurred. Moreover, KAD-1229 did not modify the activities of 6-phosphofructo 2-kinase or fructose-2,6-bisphosphatase, but increased significantly the accumulation of fructose 6-phosphate in hepatocytes. These results suggest that KAD-1229 has extrapancreatic effects on hepatic glucose metabolism, that its actions are mediated through the inhibition of fructose-1,6-bisphosphatase and stimulation of both the 6-phosphofructo 1-kinase reaction and tricarboxylic acid cycle activity by increasing the F-2,6-P2 content in hepatocytes, and that these multiple effects may account in part for the ability of KAD-1229 to reduce blood glucose levels in vivo.
We have examined the possibility that 125I-insulin binding by isolated rat hepatocytes is modulated by cellular ATP levels. To avoid complications due to ATP-dependent internalization of bound insulin, 125I-insulin binding was determined at 10 degrees C; at this temperature, equilibrium binding was achieved after incubation for 4-6 h. When hepatocytes were incubated at 37 degrees C under anaerobic conditions, ATP levels and 125I-insulin binding were both lowered by about 65%. Anoxia inhibited the association of 125I-insulin with the hepatocyte receptor; the dissociation of insulin from hepatocytes was not affected. Cellular ATP levels and 125I-insulin binding were both restored when anaerobic cells were incubated further at 37 degrees C under aerobic conditions. When anaerobic cells were incubated in air at 10 degrees C during the insulin binding assay, 125I-insulin binding recovered completely, but ATP levels were unaffected. The inhibitory effect of anoxia on 125I-insulin binding was not due to any effect on 125I-insulin degradation or on cell viability. We conclude (1) that the ability of hepatocytes to bind insulin can be modulated on a short-term basis in response to the metabolic status of the cell, and (2) that modulation of the liver cell insulin receptor is not a function of cellular ATP levels.
The internalization and intracellular distribution of 125I-insulin-like growth factor II (125I-IGF II) in mouse isolated pancreatic acini was studied by electron microscope autoradiography. 125I-IGF II was rapidly internalized; after 30 min over 70% of silver grains derived from the bound hormone were localized over the interior of the cells. The grain distribution from 125I-IGF II differed significantly from both a random grain distribution and that derived from bound 125I-insulin. The majority of intracellular 125I-IGF II grains were over the endoplasmic reticulum and Golgi; the Golgi showed the highest density of intracellular grains. Pretreatment of acini with 10 nM cholecystokinin octapeptide (CCK 8) reduced both the amount of acinar-associated IGF II and the density of intracellular 125I-IGF II grains. Moreover, CCK 8 altered the relative distribution of grains from 125I-IGF II between organelles. These studies indicate, therefore, that 125I-IGF II is internalized by pancreatic acini, and that this internalization is regulated by CCK 8.
To evaluate the role of insulin receptors in the pathogenesis of insulin resistance observed in glucocorticoid excess, we measured 125I-insulin binding to circulating erythrocytes in 7 patients with Cushing's syndrome and 7 patients with adrenal insufficiency. Insulin receptor binding was higher in Cushing's syndrome and was lower in adrenal insufficiency, compared to normal subjects. Insulin binding decreased after transsphenoidal surgery in 2 patients with Cushing's syndrome. In addition, glucocorticoid treatment in 6 patients with adrenal insufficiency resulted in the increase of insulin binding. The biological significance of this phenomenon must await further investigation, but it does suggest that insulin resistance in glucocorticoid excess should be interpreted as an alteration of cellular mechanisms of insulin at a step distal to the insulin receptor. Increased insulin binding to the receptor is probably modulated by postreceptor events.
The present study was designed to determine the possible significance of a therapeutic dose (0.2 mg) of AO-128 on carbohydrate absorption by measuring the breath hydrogen concentration, which is an index of the amount of unabsorbed carbohydrate in the large intestine. Post-prandial hyperglycemia is common among diabetic patients. AO-128, a potent alpha-glucosidase inhibitor, suppressed post-prandial hyperglycemia and hyperinsulinemia in healthy volunteers at a dose of 0.2 mg with each meal. These volunteers increased the breath hydrogen concentration in response to ingestion of non-absorbable lactulose, but decreased only slightly its concentration from the basal level after sucrose ingestion, indicating complete absorption. When AO-128 (0.2 mg) was given with sucrose, hydrogen production increased only slightly compared with placebo, suggesting that the inhibitory effect of AO-128 on sucrose absorption was minimal. Only 5 g of the 100 g of sucrose was not absorbed and this 5% reduction is too small to explain the observed inhibitory effect on the post-prandial rise in plasma glucose. Sucrose loading in rats (about 443 mg) sharply increased blood glucose and was accompanied by the rapid disappearance of sucrose from the upper small intestine. AO-128 (0.03 or 0.1 mg/kg) lessened the elevation of blood glucose after sucrose ingestion. The lower dose (0.03 mg/kg) retarded small intestinal absorption, but did not induce an influx of sucrose into the cecum and large intestine, while the higher dose (0.1 mg/kg) caused an increased influx of sucrose into the large bowel. These results indicated that AO-128 retards the absorption of carbohydrate and reduces post-prandial hyperglycemia.
The present study was undertaken to clarify a role of interleukin-12p40 gene (IL-12B) polymorphism, located on chromosome 5q33-34 (IDDM 18), in Japanese subjects with Type 1 diabetes mellitus (T1DM) and autoimmune thyroid diseases (AITD). In 179 subjects with T1DM, 166 with AITD (128 with Graves' disease and 38 with Hashimoto's thyroiditis) and 115 healthy control subjects, the IL-12B 3'UTR A-C polymorphism was determined by PCR-RFLP method. In T1DM subjects, the genotype was also analyzed in relation to human leukocyte antigen (HLA)-DRB1-DQB1 haplotype status. There was a weak difference in the distribution of the genotype frequency between T1DM and control subjects, and the C allele frequency was higher in T1DM subjects (P<0.05). In 68 T1DM subjects without having high-risk HLA haplotypes to T1DM in this population, the genotype distribution and C allele frequency was significantly different from control subjects without high-risk HLA haplotypes (P<0.01), and from T1DM subjects with high-risk HLA haplotypes (n=111) (P<0.05). There was no difference in the genotype and allele frequencies between AITD and control subjects. In conclusion, the IL-12B 3'UTR A-C polymorphism did not seem to play a major role on genetic susceptibility to T1DM and AITD in Japanese, although the polymorphism conferred susceptibility in T1DM subjects without having high-risk HLA haplotypes. The IL-12B 3'UTR A-C polymorphism would be considered as a supplementary risk factor to T1DM in conjunction with HLA haplotypes.
The mechanisms of hypoglycaemic action of a 'second-generation' sulphonylurea, gliclazide, and a synthetic human growth hormone fragment, hGH 6-13 (Leu-Ser-Arg-Leu-Phe-Asp-Asn-Ala), were compared at the cellular level in rats. Both compounds were shown to be hypoglycaemic in vivo although their molecular structures were totally different. Gliclazide was markedly insulinotropic, as are all hypoglycaemic sulphonylureas, whereas hGH 6-13 had no visible effect on basal levels of plasma insulin. However, in vitro studies with isolated pancreatic islets revealed that hGH 6-13 significantly augmented insulin secretion in the presence of exogenous glucose. One other major difference was that gliclazide had no direct effect on insulin receptor function while the synthetic hGH 6-13 increased the binding of insulin to specific receptors on isolated cells. Results suggested that the human growth hormone fragment hGH 6-13 could be a potential anti-diabetes drug with the ability to potentiate circulating insulin action and to achieve blood glucose normalisation.
Aims: To investigate the effect of apelin-13 and the antagonist of apelin receptor (F13A) on retinal Müller cells in vitro. Methods: Localization of apelin-13, GFAP and VEGF of Müller cells was detected by immunofluorescence. The effects of apelin-13 and F13A on cell function were assessed by MTT, spreading assay, apoptosis and Boyden chamber assay in vitro. Additionally, the mRNA and protein of apelin-13, GFAP and VEGF in cultured Müller cells were measured by real-time PCR and western blot. Results: Under hypoxia, strong positive staining of apelin-13 was observed and particularly evident in the cytosol and around the nucleus. Exposure of Müller cells to hypoxia led to a progressive increase in mRNA (p<0.01) and protein levels of apelin-13 (p<0.01), with a maximal 2.5-fold and 2-fold stimulation at 4h respectively, compared with normoxic controls. Treated with 0.1, 1, 10 and 100 ng/ml apelin-13, the protein level of GFAP (p<0.01) and VEGF (p<0.01) increased significantly in Müller cells in a dose-dependent manner after 24h. Compared with the untreated cells, 10 ng/ml apelin-13 significantly promoted Müller cells migration (p<0.01). Annexin/PI staining showed that apelin-13 can downregulate cell apoptosis with 30% to the most (p<0.05). On the contrary, 20 ng/ml F13A-treated Müller cells spread less than the control cells, with significantly lower number of migrated cells and significantly higher rate of apoptosis. Conclusions: The results of this study showed that apelin-13 modulated the proliferation, migration, spreading, survival of Müller cells and the expressions of GFAP and VEGF.
Werner's syndrome is an autosomal recessive disease caused by mutation of the WRN gene, which may lead to DNA repair failure and acceleration of aging. A polymorphism at amino acid 1367 Cys (TTG)/Arg (CTG) reportedly reduces the risk of myocardial infarction in Japanese. We studied the possible involvement of this polymorphism in type 2 diabetes. When polymorphism of the WRN gene was analyzed in 272 randomly recruited type 2 diabetic subjects (age 64.5+/-11.1), we found those with Cys/Arg to be older than those with Cys/Cys (p=0.021) and that the age at diagnosis of diabetes was greater in Cys/Arg than in Cys/Cys subjects (p=0.011). Diabetes-free survival rate over the age, analyzed by Kaplan-Meier method, differed significantly between these two genotype groups (p=0.0125) and the survival curve was shifted to the right in the Cys/Arg group as compared to the Cys/Cys group. No difference in allele frequency was observed between our diabetic (n=272) and non-diabetic subjects (n=171, age 66.0+/-8.0). These results suggest that the 1367 Arg allele of the WRN gene protects against the development of type 2 diabetes mellitus in Japanese.
Top-cited authors
Suvi Karuranga
  • International Diabetes Federation
Jonathan Shaw
  • Baker Heart and Diabetes Institute
Belma Malanda
  • International Diabetes Federation
Katherine Ogurtsova
  • German Diabetes Center
Stephen Colagiuri
  • The University of Sydney