Contribution of Pancreatic αcells Function to Blood Glucose Regulation in Chinese Type 2 Diabetics- the Effect of Sitagliptin on Glucagon Secretion, Insulin Secretion and Insulin Resistance in Chinese Type 2 Diabetics

Study Overview
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Brief Summary
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The purpose of this study is to determine whether Sitagliptin therapy suppress glucagon release and improve glucose control in Chinese type 2 diabetic. There are different effects of Sitagliptin therapy on blood glucose regulation, pancreatic alpha & beta cell function are different in lean (BMI<25) and overweight (BMI>25) Chinese type 2 diabetics. The purpose of this study is to determine whether glucagon release may contribute over 30% to the hyperglycemia in Chinese type 2 diabetics.

Conditions
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Insulin Secretion, Insulin Resistance

Intervention / Treatment
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* Drug: Sitagliptin


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age: 25 60 years Duration of disease < 3 years,no drug treatment for diabetes Newly diagnosed type 2 diabetic patients (fasting plasma glucose > 7.0mmol/L or/and 2h postprandial blood glucose>11.1mmol/L WHO 1999) Fasting plasma glucose < 10 mmol/L Exclusion Criteria: Type 1 diabetes DKA, infection and other stress status Autoimmune disease Hepatic and renal diseases

Ages Eligible for Study
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Minimum Age: 25 Years
Maximum Age: 60 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: Sitagliptin treatment<br> | Drug: Sitagliptin<br>* Sitagliptin 100 mg QD for 12 weeks<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change From Baseline in Hemoglobin A1c (HbA1c) |  | Baseline to 12 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change From Baseline in Fasting Plasma Glucose (FPG) |  | Baseline to 12 weeks | 
| Change From Baseline in Postprandial Plasma Glucose (PPG) |  | Baseline to 12 weeks | 
| Change From Baseline in Insulin Sensitivity | The insulin sensitivity was detected by evaluating the glucose infusion rate (GIR) with euglycemic hyperinsulinemic clamp test. | Baseline to 12 weeks | 
| Change From Baseline in Insulin Sensitivity in Patients With Different BMI | The insulin sensitivity was detected by evaluating the glucose infusion rate (GIR) with euglycemic hyperinsulinemic clamp test. | Baseline to 12 weeks | 
| Change From Baseline in Pancreatic β Cell Function | The early phase insulin response (△I30/△G30) was adopted to determine β cell function. | Baseline to 12 weeks | 
| Change From Baseline in Pancreatic β Cell Function in Patients With Different BMI | The early phase insulin response (△I30/△G30) was adopted to determine β cell function. | Baseline to 12 weeks | 
| Change From Baseline in Pancreatic α Cell Function | The glucagon-AUC was adopted to show pancreatic α cell function. | Baseline to 12 weeks | 
| Change From Baseline in Pancreatic α Cell Function in Patients With Different BMI | The glucagon-AUC was adopted to show pancreatic α cell function. | Baseline to 12 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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glucagon, dipeptidyl peptidase-4 inhibitor