Evaluate the Effect of Exenatide Treatment on Coronary Artery Endothelial Function

Study Overview
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Brief Summary
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Type 2 diabetes mellitus (T2DM) is an important risk factor of cardio-cerebral vascular disease such as coronary heart disease. GLP-1 is a kind of incretin secreted by the L-cell located in Ileum. It acts as an incretin hormone by protentiating glucose-stimulated insulin release. Recent studies reported that GLP-1 RA can protect the vascular endothelial and prevent vascular from atherosclerosis. Investigators design this study to investigate exenatide's effect on the improvement of the coronary endothelial function by evaluating endothelium dependent diastolic function and testing the vascular endothelial active substance and related inflammatory factors.

Conditions
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Coronary Endothelial Function

Intervention / Treatment
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* Drug: Byetta (Exenatide)
* Drug: Glucophage ( Metformin Hydrochloride)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Females or males, and aged 20 to 65 years Newly diagnose type 2 diabetes mellitus with BMI>25kg/m2. HbA1C>8%. Exclusion Criteria: Type 1 diabetes mellitus, diabetic ketoacidosis, diabetic hyperosmolar coma. Hepatic insufficiency (ALT or AST> 1.5*ULN). Renal insufficiency [Creatinine clearance rate (Ccr)]<60ml/min estimated from MDRD equation). Thyroid disease Use of any anti-diabetic, anti-hypertension or anti-dyslipidemia drugs. Pregnant or lactating woman. Severe anemia. Acute myocardial infarction or stoke. Other conditions at investigator's discretion.

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 65 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
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Lifestyle intervention<br> | Drug: Byetta (Exenatide)<br>* Exenatide treatment: 5 µg twice/day subcutaneous injection for 4 weeks, 10 µg twice/day subcutaneous injection for 8 weeks.<br>Drug: Glucophage ( Metformin Hydrochloride)<br>* Metformin 500mg Tid<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Coronary endothelial function | the change of coronary flow velocity reserve (CFVR)(baseline, 12 weeks) | the change of coronary endothelial function(baseline, 12 weeks) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| the changes of fasting plasma glucose (FPG) | the changes of fasting plasma glucose (FPG) (baseline, 12 weeks) | the changes of fasting plasma glucose (FPG)(baseline, 12 weeks) | 
| the changes of HbA1C | the changes of HbA1C (baseline, 12 weeks) | the changes of HbA1C(baseline, 12 weeks) | 
| the changes of fasting serum insulin (FINS) | the changes of fasting serum insulin (FINS) (baseline, 12 weeks) | the changes of fasting serum insulin (FINS) (baseline, 12 weeks) | 
| the changes of IL-1B | the changes of IL-1B (baseline, 12 weeks) | the changes of IL-1B (baseline, 12 weeks) | 
| the changes of IL-6 | the changes of IL-6 (baseline, 12 weeks) | the changes of IL-6 (baseline, 12 weeks) | 
| the changes of TNF-α | the changes of TNF-α(baseline, 12 weeks) | the changes of TNF-α(baseline, 12 weeks) |