Exercise training lowers plasma visfatin concentrations in patients with type 1 diabetes.

CONTEXT: Exercise training exerts beneficial effects on metabolic and vascular risk factors in patients with type 1 diabetes mellitus (T1DM). It is unknown whether training also influences concentrations of visfatin, a novel insulin-mimetic adipocytokine. OBJECTIVES: In this study, we have investigated whether plasma visfatin concentrations are altered by training in patients with T1DM. DESIGN AND PATIENTS: Fasting plasma visfatin concentrations and metabolic parameters were measured in 18 patients with T1DM who participated in a supervised aerobic exercise program for 4 months. Three subjects discontinued training prematurely after 2 months. Samples were obtained before and during training and 8 months after the end of regular exercise. Fourteen healthy young subjects served as controls. RESULTS: At baseline, patients with T1DM had higher visfatin concentrations than controls (64.1 +/- 12.0 vs. 1.3 +/- 0.0 ng/ml, P < 0.01). Exercise reduced visfatin after 2 and 4 months to 27.8 +/- 2.6 (n = 18) and 17.5 +/- 3.4 ng/ml (n = 15), respectively (P < 0.001 for n = 15 subjects who participated in all visits, ANOVA). This effect was maintained 8 months after cessation of training, with visfatin concentrations of 19.7 +/- 5.0 ng/ml (n = 15). Metabolic parameters were not affected by the training program. CONCLUSION: Elevated visfatin concentrations in patients with T1DM can be lowered by regular physical exercise. It is unknown whether glucose tolerance is affected by changes in visfatin concentrations.

Regular physical exercise normalizes elevated asymmetrical dimethylarginine concentrations in patients with type 1 diabetes mellitus.

INTRODUCTION: Levels of the endogenous nitric oxide synthase inhibitor asymmetrical dimethylarginine (ADMA) are elevated in patients with type 1 diabetes mellitus (DM1) and may contribute to vascular complications. In this study we tested the hypothesis that elevated ADMA in patients with DM1 can be reduced by regular physical exercise. METHODS: Plasma samples for analysis of L-arginine, ADMA, symmetrical dimethylarginine (SDMA) and metabolic parameters were obtained from 11 patients with DM1 who participated in a supervised aerobic exercise program for four months. Samples were collected before the training began, at two and four months after initiation, and eight months after cessation of regular training. Fifteen age- and sex-matched healthy persons who did not exercise regularly were examined once as controls and did not participate in the training program. RESULTS: The patients with DM1 had higher ADMA levels than the controls before the training program began (0.54 +/- 0.02 vs. 0.44 +/- 0.03 micromol/l; P < 0.05). After two and four months of exercise, ADMA concentrations in the patients decreased to those seen in healthy persons (0.42 +/- 0.02 and 0.43 +/- 0.03 micromol/l; P < 0.001 and P < 0.05 compared with ADMA levels before training began). Eight months after cessation of the exercise program, ADMA levels in the patients reverted to those observed before the start of training. The L-arginine-to-ADMA ratio increased slightly after two months; L-arginine, symmetrical dimethylarginine, blood lipids and HbA1c were not affected by the training program. CONCLUSIONS: Elevated ADMA levels in patients with DM1, who have a high risk for developing cardiovascular disease, can be lowered to those of healthy persons by regular physical exercise. This favorable effect on ADMA is not sustained when training is discontinued.

Exercise training improves vascular endothelial function in patients with type 1 diabetes.

OBJECTIVE-Impaired endothelial function of resistance and conduit arteries can be detected in patients with type 1 diabetes. We studied whether a persistent improvement of endothelial function can be achieved by regular physical training. RESEARCH DESIGN AND METHODS-The study included 26 patients with type 1 diabetes of 20 +/- 10 years' duration and no overt angiopathy; 18 patients (42 +/- 10 years old) participated in a bicycle exercise training program, and 8 patients with type 1 diabetes (33 +/- 11 years old) served as control subjects. Vascular function of conduit arteries was assessed by flow-mediated and endothelium-independent dilation of the brachial artery and of resistance vessels by the response of ocular fundus pulsation amplitudes to intravenous N(G)-monomethyl-L-arginine (L-NMMA) at baseline, after 2 and 4 months of training, and 8 months after cessation of regular exercise. RESULTS-Training increased peak oxygen uptake (VO(2max)) by 13% after 2 months and by 27% after 4 months (P = 0.04). Flow-mediated dilation (FMD) of the brachial artery increased from 6.5 +/- 1.1 to 9.8 +/- 1.1% (P = 0.04) by training. L-NMMA administration decreased fundus pulsation amplitude (FPA) by 9.1 +/- 0.9% before training and by 13.4 +/- 1.5% after 4 months of training (P = 0.02). VO(2max), FMD, and FPA were unchanged in the control group. Vascular effects from training were abrogated 8 months after cessation of exercise. CONCLUSIONS-Our study demonstrates that aerobic exercise training can improve endothelial function in different vascular beds in patients with long-standing type 1 diabetes, who are at considerable risk for diabetic angiopathy. However, the beneficial effect on vascular function is not maintained in the absence of exercise.

Evaluation of a new insulinotropic agent by using an innovative technology: efficacy and safety of nateglinide determined by continuous glucose monitoring.

Nateglinide, a new insulinotropic agent, specifically targets prandial glycemic excursions. Recently, innovative technologies have become available that provide the possibility to measure 72-h blood glucose values continuously. The aim of this study was to evaluate the effects of nateglinide on 24-h blood glucose profiles in diabetic patients. Eighteen patients with type 2 diabetes mellitus--seven on diet only and 11 on metformin monotherapy--participated in the study. Mean age was 60 years, mean diabetes' duration was 7.4 years, and mean hemoglobin A1c was 8.4%. They underwent a 72-h glucose monitoring using a continuous glucose monitoring system (CGMS, Medtronic MiniMed, Northridge, CA) under their usual diabetes therapy and a standardized breakfast. After this period, therapy with nateglinide, 120 mg three times a day before meals, was initiated. Three days later patients again underwent 72-h glucose monitoring. Mean blood glucose values and mean fasting blood glucose values decreased significantly, from 172 mg/dL before to 131 mg/dL (P< 0.0004) and from 172 mg/dL before to 126 mg/dL (P< 0.0005), respectively, with nateglinide therapy. Postprandial hyperglycemia, expressed as mean blood glucose over a time period of 2 h after a meal, declined significantly after all three daily meals. The number of blood glucose values above 140 mg/dL decreased from 207 without to 98 during nateglinide therapy. Nateglinide was not associated with hypoglycemia or other adverse events. We found in this study, using CGMS, that nateglinide has a glucose-lowering potency that not only affects postprandial hyperglycemia, but also overnight and fasting blood glucose values.

[The diabetic foot]. / Diabetischer Fuß

These are the guidelines for preventive care, diagnosis and treatment of the diabetic foot syndrome. Diabetic neuropathy, peripheral vascular disease, bone deformity and altered biomechanics are foot-related risk conditions. The position statement is focused on screening methods and recommendations for clinical care for diabetics, who currently have no foot ulcers. A decision pathway is offered with respect to diagnosis and management of diabetic patients at an increased risk or manifest injuries.

[Diabetic neuropathy]. / Die diabetische Neuropathie.

These are the guidelines for diagnosis and treatment of diabetic neuropathy. This diabetic late complication comprises a number of mono- and polyneuropathies, plexopathies, radiculopathies and autonomic neuropathy. The position statement summarizes characteristic clinical symptoms and techniques for diagnostic assessment of diabetic neuropathy. Recommendations for the therapeutic management of diabetic neuropathy, especially for the control of pain in sensomotoric neuropathy, are provided.

Treatment with alpha-lipoic acid reduces asymmetric dimethylarginine in patients with type 2 diabetes mellitus.

Elevated asymmetric dimethylarginine (ADMA) concentrations predict cardiovascular events in patients with type 2 diabetes mellitus (T2DM). It has been shown that alpha-lipoic acid (ALA) improves endothelial function and oxidative stress in these patients. The present study investigated if ALA reduces ADMA in patients with T2DM. Plasma concentrations of ADMA, L-arginine and symmetric dimethylarginine (SDMA) were determined in a double-blind, randomized, placebo-controlled study in patients with T2DM. Intravenous ALA (n = 16) or placebo (n = 14) was administered daily for 3 weeks. ALA reduced ADMA while no change was observed with placebo (mean change -0.05 micromol/1[95% CI: -0.01; -0.09] vs. 0.01 micromol/1 [95% CI: -0.05; -0.03]; ANOVA p = 0.031). SDMA and L-arginine were not affected by ALA. In conclusion ALA treatment reduces ADMA in patients with T2DM. Long-term studies need to demonstrate if ALA may cause cardiovascular risk reduction.

[Diabetic neuropathy]. / Diabetische Neuropathie.

These are the guidelines for diagnosis and treatment of diabetic neuropathy. This diabetic late complication comprises a number of mono- and polyneuropathies, plexopathies, radiculopathies and autonomic neuropathy. The position statement summarizes characteristic clinical symptoms and techniques for diagnostic assessment of diabetic neuropathy. Recommendations for the therapeutic management of diabetic neuropathy, especially for the control of pain in sensorimotoric neuropathy, are provided.

[The diabetic foot]. / Diabetischer Fuss.

These are the guidelines for preventive care, diagnosis and treatment of diabetic foot syndrome. Diabetic neuropathy, peripheral vascular disease, bone deformity and altered biomechanics are foot-related risk conditions. The position statement is focused on screening methods and recommendations for clinical care for diabetics, who currently have no foot ulcers. A decision pathway is offered with respect to diagnosis and management of diabetic patients at increased risk or who manifest injuries.