Effects of Sitaglpitin on Endothelial Function During the OGTT in T2DM

Study Overview
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Brief Summary
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To investigate whether single administration of sitaglitpin can restore acute endothelial dysfunction and ameliorate impaired increase of the number of endothelial progenitor cells (EPCs) after oral glucose loading in patients with T2DM. To compare the effect of sitagliptin and glimepiride on endothelial function evaluated by flow-mediated vasodilatation (FMD) and the number of circulating EPCs in patients with T2DM.

Detailed Description
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Acute and chronic improvement of endothelial function is expected through the pleiotropic effect of DPP-4 inhibitors. A randomized, prospective, open-labeled, parallel design. The duration of treatments with sitagliptin or glimepiride is 12 weeks. The number of study centers is a single (Dokkyo Medical University Hospital). Participants will be randomized into the two treatment groups; (a) 50mg sitagliptin (N=15) and (b) 1mg glimepiride (N=15). Anti-Hyperglycemic effect is expected to be similar according to our study

Official Title
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A Randomized, Prospective, Parallel Design Study to Compare the Effectiveness of Sitagliptin Versus Glimepiride on Endothelial Dysfunction During an Oral Glucose Loading in Drug Naive Patients With Type 2 Diabetes.

Conditions
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Type 2 Diabetes

Intervention / Treatment
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* Other: dieting
* Drug: Sitagliptin
* Drug: Glimepiride


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Provision of informed consent before any study specific procedures Type II diabetes who have inadequate glycaemic control (6.5%≦HbA1c<9.0%) Age from 20 to 80 years old No history of using any antihyperglycemic drugs No history of cardiovascular complications No treatment or treatment with stable doses of lipid-lowering, antihypertensive, and antiplatelet agents for at least 3 months prior to randomization 4.5 % ≤ fasting FMD at baseline < 8.0 % Exclusion Criteria: ・Type I diabetes Pregnancy Liver disease (hepatic enzymes more than three times the upper limit of normal ranges) Impairared kidney function (serum crearinine greater than 1.3 mg/dl in men, 1.2 mg/dl in women) Cigarette smokers Contraindications to glimepiride and sitagliptin Active proliferative diabetic retinopathy

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Sitagliptin<br>sitagliptin 50 mg tablet by mouth 12 weeks | Other: dieting<br> <br> Drug: Sitagliptin<br>* sitagliptin 50 mg tablet by mouth 12 weeks<br>|
| Active Comparator: Glimepiride<br>glimepiride 1 mg tablet by mouth 12 weeks | Other: dieting<br> <br> Drug: Glimepiride<br>* glimepiride 1 mg tablet by mouth 12 weeks<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in endothelial function during the OGTT evaluated by flow-mediated vasodilatation (FMD). The change is defined as below, assuming the peak value and changes of FMD will be observed at t=60 min. |  | 12 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in endothelial function during OGTT* evaluated by endo-PAT. Change in endothelial function after 12-week treatment at the fasting state evaluated by endo-PAT and FMD. |  | 12 weeks |