Oral Communications

A1170 Weighted influence of glucose levels at different times of the day on HbA1c in insulin-treated type 2 diabetic patients. The Diabetes Outcomes in Veterans Study (DOVES) J Shah*, G Murata, C Wendel*, R Hoffman, W Duckworth and M Mohler* *Southern Arizona VA Health Care System, Endocrinology, Tucson, AZ, USA, New Mexico VA Health Care System, General Medicine, Albuquerque, NM, USA, Carl T. Hayden VA Medical Center, Endocrinology, Phoenix, AZ, USA

On behalf of the Hvidore Study Group on Childhood Diabetes Aims: To evaluate whether nutritional intake, eating habits and lifestyle activities have an influence on glycemic control and the center differences in a large international cohort of adolescents with type 1 diabetes. Methodology: Cross-sectional clinical data were collected and questionnaires completed by adolescents and parents/carers attending clinics in 21 International centers. HbA1c (DCCT adjusted) was measured centrally. Results: Questionnaires were completed by 2062 adolescents (age: 14.4 ± 2.3 years; 50.6% male; diabetes duration: 6.1 ± 3.5 years). Mean HbA1c was 8.2% ± 1.4% with a significant difference between centers (F = 12.3; P < 0.001) ranging from 7.4% to 9.3%. BMI showed no differences between males and females, it had no association with HbA1c and no center differences were observed. Adolescents who binge more frequently have poorer HbA1c (r = 0.2) as do those who skip breakfast during weekdays or snack regularly between lunch and dinner. Food frequency items were subjected to factor analysis. Two food groups were extracted (wholesome foods e.g. fruit, vegetables, brown bread: and calorie dense foods e.g. pastries, cola, chips, burgers). Greater consumption of wholesome foods was associated with lower HbA1c (r = 0.04) and greater consumption of calorie dense foods was associated with higher HbA1c (r = 0.08), with significant differences between centers with regard to calorie dense (F = 14.7; P < 0.001) and wholesome foods (F = 12.7; P < 0.001). Physical activity was not associated with HbA1c (r = (-0.005) but individuals who spent more time watching TV had higher HbA1c (r = 0.03) and who spent more time doing homework had lower HbA1c (r = 0.08). With these measures significant center differences were found (TV F = 2.51 P < .001; homework F = 16.3; P < 0.001). In multi-variate analysis, adding these diet and lifestyle effects marginally reduces the impact of the center on HbA1c (center alone F = 12.9; center after food and activity added F = 11.7). Conclusions: For individuals, food intake of particular 'unhealthy' nutrients as well as skipping breakfast, bingeing and more TV watching are associated with poorer glycemic outcomes. However, these lifestyle differences do not seem to have a strong influence on the center differences between 21 international centers.

A1172
The Continuous Glucose Monitoring System (CGMS) as an aid in adjusting complex treatment regimens and improving office diabetes management A Rizvi and M Sanders Division of Endocrinology, University of South Carolina School of Medicine, Diabetes Unit, Columbia, SC, USA Method: We used the Continuous Glucose Monitoring System (CGMS, Medtronic Minimed) technology to evaluate blood glucose patterns in 24 patients with diabetes treated with insulin. Their characteristics were as follows: 13 female, 11 male, mean age 45 years, 10 with type 1 and 14 with type 2 diabetes, 14 treated with multiple-dose insulin injections and 10 with insulin pump therapy. Patients were selected for CGMS because of one or more of the following reasons: unexplained elevated hemoglobin A1c, unpredictable glycemic variability, severe or frequent hypoglycemia, suspected nocturnal hyper-or hypoglycemia, postprandial hyperglycemia, presence of dawn phenomenon, to evaluate the effect of activity, menstrual cycle, exercise, therapeutic modification, and to ascertain the accuracy of carbohydrate counting, exchange sizes, or supplemental factor calculations. A 3-day recording was obtained with indicators for food and insulin timing while the patient kept a diary of daily activities. The information was downloaded retrospectively by a specialty nurse and the tracings analysed by a diabetologist. Results: As a result of detailed data obtained from the CGMS recordings, the following changes were made: the basal insulin was adjusted 12 patients, short-acting bolus insulin doses were modified for better postprandial control in four patients, hypoglycemic episodes were confirmed or uncovered in five patients, insulin-to-carbohydrate ratio was changed in six patients, and supplemental factor adjusted in five patients. Pump settings modified in one pregnant patient in order to achieve glycemic targets. A comparison over a 6-month time period before and after these adjustments, showed a decrease in mean hemoglobin A1c from 7.57% to 6.87%. Conclusions: In a setting where diabetes expertise is available, the CGMS can be a valuable tool that gives useful information in assessing glucose patterns, adjusting and fine-tuning intensive insulin therapy, improving glycemic control, and picking up treatment-related hypoglycemia.

A1173
Internet-based blood glucose management system (IBGMS) using personal digital assistants (PDA) in a rural heath subcentre H Kwon*, Y Park † , S Hong*, Y Choi*, W Lee † , B Cha*, H Son* and K Yoon* *Department of Internal Medicine, The Catholic University of Korea, Seoul, Korea, South, † Department of Preventive Medicine, The Catholic University of Korea, Seoul, Korea, South Aims: To evaluate the efficacy of previously developed the Internetbased Blood Glucose Monitoring System (IBGMS) using personal digital assistants (PDA) with glucose monitoring device in the care of the diabetic patients of rural health subcenter where diabetic patients have fewer chances to get medical help from health care provider. Methods: Fifty-seven type 2 diabetic patients with their HbA1c < 11% were enrolled and randomized into the intervention and the control group. In the intervention group, Community Health Nurse Practitioner (CHNP) checked patients' blood glucose levels using PDA regularly and sent the data including patients' medication, amount of meal, and degree of exercise to IBGMS. Then endocrinology specialist, dietitians, and nurses sent recommendations for individualized diabetes management to CHNP. In the control group, CHNP just checked patients' blood glucose levels and gave general information without any helps or contact with IBGMS. Results: Fasting plasma glucose levels of both the intervention (n = 31) and control (n = 28) group were decreased after 3 months without significant difference (from 139.1 ± 39.1 to 128.9 ± 33.0 mg/dl in intervention vs. from 155.6 ± 34.2 to 144.1 ± 45.7 mg/dl in control). HbA1c of the intervention group was significantly improved after 3 months compared with that of control (mean difference 0.59 ± 0.69 in intervention group vs. 0.14 ± 0.85 in control, P = 0.029). Several parameters regarding dietary habits and exercise were also significantly improved in the intervention group. Conclusion: This study results suggested that IBGMS using PDA was effective management system for diabetic patients in rural health subcenter. And PDA with glucose monitoring device was a useful tool for caring the diabetic patients with limited medical helps.

Oral Communications
Insulin secretion A1174 Thrombospondin-1: produced by islet endothelial cells and crucial for beta-cell function J Olerud*, M Johansson*, Å Johansson*, N Welsh* and P Carlsson* † *Uppsala University, Medical Cell Biology, Uppsala, Sweden, † Uppsala University Hospital, Medical Science, Uppsala, Sweden Aims: The glycoprotein thrombospondin-1 (tsp-1) has previously been shown to be a major activator of transforming growth factor beta-1 (TGFbeta1) in vivo. In pancreatic islets, TGFbeta1 is pivotal for beta-cell function by inducing PDX-1 expression. This study aimed to investigate if tsp-1 is produced in adult pancreatic islets, and, if so, by which cells and if it is important for beta-cell function.
Methods: Immunohistochemistry stainings of mouse and rat pancreas, combined with real time PCR for tsp-1 mRNA on whole islets, beta-cells or islet endothelial cells, were performed to reveal the islet cells that produce tsp-1. Beta-cell function was characterised by blood glucose tolerance tests, and studies of insulin release, insulin content, (pro)insulin biosynthesis and glucose oxidation rate on isolated islets obtained from 10 week old C57BL/6 and Tsp-/-mice. Results: Immunohistochemistry stainings suggested that tsp-1 mainly was produced in islet endothelium and sequestered to the islet matrix. Levels of tsp-1 mRNA were 15-25 times higher in rat and mouse islet endothelial cells compared with whole islets, and not even detectable in bTC-6 cells. The functional role of tsp-1 was investigated in tsp-1 deficient mice. Such mice were found to be markedly glucose intolerant with low circulating serum insulin levels, despite normal to increased beta-cell mass. Moreover, islets isolated from these mice had decreased glucose-stimulated insulin release, (pro)insulin biosynthesis and glucose oxidation rate when compared with control islets.
Conclusions: Tsp-1 seems not to be expressed in beta-cells, but at high levels in islet endothelial cells. Its effects on beta-cell function may therefore relate to paracrine interactions between endothelial and beta-cells, as recently described also for hepatocyte growth factor and laminin. Further experiments are now conducted to selectively reconstitute tsp-1 in the endothelial cells of tsp-deficient islets.

A1175
Decreased metabolic enzymes and hydroxynonenal-protein adducts in pancreatic islets from human type 2 diabetic patients Methods: Large-scale isolation of islets was performed from pancreata of cadaver donors. Islet insulin secretion was studied and enzyme activity assays were used in addition to gene expression microarrays (Affymetrix).
Results: Glucose-stimulated insulin release was markedly impaired in islets from diabetic patients; the release at 16.7 mm glucose amounting to about one-third of that in control islets. The activities of mGPDH and PC were decreased in human diabetic islets relative to control islets by about 75%, i.e. a greater decrease than previously found in islets of diabetic rodents. The enzyme activities of ATP citrate lyase (ATP-CL) and propionyl-CoA carboxylase (PCC) were also decreased, by 40% or more. Relative levels of mRNA transcripts encoding for these enzymes were estimated with gene expression microarray analysis, and in general these data corroborated the enzyme activity data. A new observation was that immunoblot analysis showed that the lipid peroxide hydroxynonenal (HNE) was bound covalently to a 46 kDa protein in pancreatic islets from diabetic and controls. This finding is relevant to the hypothesis that lipotoxicity is a factor causing beta cell dysfunction in type 2 diabetes. Conclusions: Our data show that islets of type 2 diabetic patients demonstrate decreased mGPDH and PC enzyme activity. In addition, ATP-CL and PCC enzyme activities were lower and mRNA transcripts to many of these enzymes were also low relative to controls. The results also show for the first time that islets of human type 2 diabetics and non-diabetics possess an HNE-protein adduct. It is interesting to speculate that these findings may partially explain impaired beta cell function, associated with hyperglycemia and hyperlipidemia in type 2 diabetes.

A1176
Insulin secretion and insulin sensitivity in people with impaired glucose regulation Aims: Substantial progress in understanding the underlying defects in diabetes mellitus has led an etiological classification of the disorder. However, the same has not yet been possible for the pre-diabetic stages termed as Impaired Glucose Regulation (IGR) by WHO and lesser degrees of impaired glucose regulation by ADA expert committees. In particular, the phenotype of combined impaired fasting glucose (IFG) and impaired glucose tolerance (IGT) has not been adequately addressed. The present study was undertaken to explore the pancreatic B cell function and insulin sensitivity of the clinical types of IGR in a Bangladeshi population. Methods: Thirteen IFG and 112 IGT subjects, along with 39 healthy controls, aged >20 years, were selected purposively from out-patient department of BIRDEM. During analysis, we also categorized IGT subjects into 91 isolated IGT (I-IGT) and 21 combined IFG-IGT subjects. Insulin secretory capacity (%B) and insulin sensitivity (%S) were assessed by homeostasis model assessment (HOMA) using HOMA-CIGMA software.  ]. HOMA %S was decreased but just outside the range of statistical significance in IFG compared to Control (P = 0.084) and in IFG-IGT to I-IGT (P = 0.069).
Conclusions: The pathophysiological mechanisms differ in IFG (primary defect of B-cell dysfunction with a tendency to insulin resistance) and isolated IGT (primarily an insulin resistant condition). The pathophysiology of the clinical entity of combined IFG and IGT (both B-cell dysfunction and insulin resistance) indicates that it may be a different clinical entity and, thus, it may not be included in IGT as done by the ADA and WHO.

A1177
Altered proinsulin conversion in rat pancreatic islets exposed long-term to various glucose concentrations or IL-1 beta A Borjesson and C Carlsson Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden Aims: In order to elucidate a possible relationship between b-cell function and conversion of proinsulin to insulin, rat pancreatic islets were maintained in culture for one week at various glucose concentrations or incubated with IL-1b for 48 h. Methods: Islets were labelled for 30 min with L-(4.5-3H) leucine and further incubated for 45 or 90 min without the radioactive precursor. After precipitation with anti-insulin anti-serum immunoreactive proteins were separated by polyacrylamide gel electrophoresis and relative contents of newly synthesized pro-insulin and insulin determined by densitometry. RT-PCR was used for analysis of mRNA expression of proinsulin converting enzymes. Results: Islets cultured at 56 mm glucose showed an increased proportion of proinsulin compared to islets cultured at 5.6 mm glucose after a 90 min chase period, however, no difference was observed after culture at 11 and 28 mm glucose. The mRNA expression of PC1 was increased after culture at 11 and 28 mM glucose, but no further increase was observed after culture at 56 mm glucose. Treatment for 48 h with IL-1b increased the proportion of proinsulin both at 45 and 90 min compared to control islets. These islets also displayed a decreased mRNA expression of proinsulin converting enzymes. Conclusions: We conclude that a sustained functional stimulation by glucose of islets is coupled to decreased conversion of proinsulin which is also true for islets treated with IL-1b. This may contribute to the elevated levels of proinsulin found both at the onset of type 1 diabetes as well as in type 2 diabetes. Aims: In diabetic peripheral neuropathy (DPN), its pathogenesis was considered by vascular and metabolic cause. When we managed diabetic neuropathic rats with antioxidant, conventional evaluation of its efficacy was difficult. In this study, we evaluate the effect of antioxidant in microvascular change of rat skin by the intravital fluorescence microscopy and color subtractive-computer-assisted image analysis. Methods: We tested the efficacy of alpha lipoic acid (ALA) in vascular change in OLETF (Otsuka Long-Evans Tokushima Fatty) rat, an animal model of type 2 diabetes, and non-diabetic Long-Evans Tokushima Otsuka (LETO) rat which were fed with sucrose until diabetes mellitus developed. Thereafter, one group of OLETF rats was fed with ALA and the other group of OLETF and LETO was not for 40 weeks. Diabetic rats were administered with ALA (80 mg/kg of body weight/day) by oral feeding for 40 weeks. The effect of ALA on vascular change was assessed by the intravital fluorescence microscopy and color subtractive-computerassisted image analysis. Quantification of neuropathic symptoms on the dorsum of hind paws of rat was measured by CPT test every 4 weeks.
Results: OLETF rats with ALA group show statistically longer vessel length and larger area than OLETFE rats without ALA group (P < 0.05) and almost similar with LETO rats. Conclusions: ALA management in experimental neuropathy show preservation effect in skin microvascular total length and area, and intravital fluorescence microscopy and color subtractive-computer-assisted image analysis is useful for evaluation of skin microvascular change.

A1180
Lower levels of peripheral neuropathy in Asians versus Europeans with diabetes: a link with improved peripheral blood flow in Asians?
C Abbott*, N Chaturvedi † and A Boulton* *Department of Medicine, University of Manchester, Manchester, UK, †

Department of Epidemiology, Imperial College, London, UK
Aims: Despite migrant populations of South Asian descent to the UK having a fourfold elevated risk of type 2 diabetes compared with the general population and increased rates of ischaemic heart disease, we have shown that foot ulceration and amputation risks are substantially lower in South Asians than White Europeans in the UK. Furthermore, we have previously demonstrated that Asians with diabetes have less clinical neuropathy (17.6%) than their White counterparts (21.8%, P < 0.001).
We now aim to confirm this using objective tests i.e. nerve conduction assessments.
Conclusions: We hypothesize that differences in peripheral microvascular flow between the ethnic groups account for these differences in peripheral nerve function. Further work is required to elucidate the contribution of improved blood flow in Asians to their lower levels of neuropathy.

A1181
Increased concentrations of soluble CD40 ligand may help to identify type 1 diabetic adolescents and young adults at risk for developing persistent microalbuminuria Aims: Soluble CD40 ligand (sCD40L) is enhanced in diabetes. We previously demonstrated that upregulation of sCD40L as a consequence of persistent hyperglycaemia results in endothelial cell activation and monocyte recruitment to the arterial wall, possibly contributing to accelerated atherosclerosis development in young type 1 diabetic patients. To the best of our knowledge no study evaluated the relationship between sCD40L and microalbuminuria. Methods: In January 1989, sCD40L was measured in 268 normoalbuminuric diabetic adolescents and young adults (age 11-24 years; onset of diabetes before age 18 years; duration of diabetes longer than 7 years). Participants were clinically examined at baseline and biennially thereafter. sCD40L was measured every 2 years during the 16-year follow-up period. sCD40L was also measured in parents and offsprings. Results: Over 16 years, 25 (14 male, 11 female) out of 268 patients (9.3%) developed persistent microalbuminuria (defined as an albumin excretion rate (AER) of more than 20 lg/min/1.73 m 2 ); no patient developed overt nephropathy. The risk of developing microalbuminuria was higher in children with increased sCD40L (using 7 ng/ml as the arbitrary cut-off point) (group A) compared with those with normal sCD40L at the beginning of the study (group B). Sex did not influence predictive value, sensitivity, or specificity. sCD40L was not significantly correlated with HbA1c or duration of type 1 diabetes. The percentage of offsprings with both parents having sCD40L above the median values was significantly higher in group A than in group B. The odds ratio for the occurrence of microalbuminuria after adjustment for confounding variables (AER, sex, HbA1c, mean blood pressure, cholesterol, triglycerides) in type 1 diabetic adolescents with elevated baseline sCD40L was 4.8 (95% CI of 1.9-12.1). Conclusions: These results demonstrate that enhanced sCD40L in the first years of diabetes may be one of the predictors and risk factors for incipient diabetic nephropathy in adolescents and young adults with onset of diabetes during childhood. Persistently increased sCD40L concentrations may help to identify normotensive, normoalbuminuric patients with type 1 diabetes who are pre-disposed to develop microalbuminuria and incipient diabetic nephropathy.

A1182
Circulating hematopoietic stem cells expressing neural markers are reduced in diabetic patients with early dementia G Passacquale*, G Desideri*, F Ruggeri † , G Croce* and C Ferri* *Department of Internal Medicine and Public Health, University of L'Aquila, L'Aquila, Italy, † Neurosurgical Department, S. Camillo-Forlanini Hospital, Rome, Italy Aims: Several epidemiological studies suggest that type 2 diabetes represents a risk factor for dementia. The effect of diabetes on cognitive impairment seem not entirely to depend on vascular complications. Many factors are responsible for brain integrity including the proliferation, death and migration of neural precursors. In this regard, a subset of bone marrow-derived neurons has been isolated from the human central nervous system (CNS) suggesting a contribution of bone marrow-derived cells to the neural tissue self-renewing. Furthermore, it has been demonstrated that hematopoietic stem cells (HSCs) generate mature neurons when in vitro treated with neural-inducing factors. We hypothesized that a reduction of circulating HSCs expressing neural markers might occur in diabetes and, in the long run, contributes to dementia development.
Methods: In the current report we evaluated the neural marker expression in circulating HSCs isolated from peripheral blood of type 2 diabetics either with Mild Cognitive Impairment (MCI) (n = 5) or without MCI (n = 10) in comparison to healthy age-matched subjects (n = 10). Particularly, we investigated through Western Blot, immunostaining and reverse-transcriptase polymerase chain reaction (RT-PCR) the expression of Sox2, a transcriptional factor expressed in the developing CNS, of neural marker neuronal nuclei protein (NeuN) and of glial fibrillary acidic protein (GFAP) in CD34+ cells.
Results: Circulating CD34+ cells spontaneously express Sox2, NeuN and GFAP in all groups. However, the expression of NeuN was lower in CD34+ cells derived from diabetics with MCI that in those obtained from diabetics without MCI. These latter manifested a lower expression of NeuN in HSCs than healthy controls. Conclusion: Our study is the first demonstration that the NeuN expression is reduced in circulating HSCs from diabetics, being this reduction particularly evident in the presence of early dementia. Our data might suggest a role for HSCs in the onset of cognitive impairment in diabetic patients.