[11C]5-Hydroxy-tryptophan PET for Assessment of Islet Mass in Type 2 Diabetes

Study Overview
=================
Brief Summary
-----------------
Cross-sectional study to investigate subjects at different stages of type 2 diabetes development with expected stratification of pancreatic islet mass. Non-diabetic individuals were assigned as control. The primary outcome was the [11C]5-hydroxy-tryptophan uptake and retention in the pancreas as a surrogate marker for the endogenous islet mass.

Official Title
-----------------
[11C]5-Hydroxy-tryptophan Positron Emission Tomography for Assessment of Islet Mass During Progression of Type 2 Diabetes

Conditions
-----------------
Type2 Diabetes

Intervention / Treatment
-----------------
* Radiation: Positron emission tomography with the tracer [11C]5-hydroxy-tryptophan


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Type 2 diabetes fulfilling criteria for the four different study groups, or healthy volunteers Exclusion Criteria: Ongoing pregnancy Renal failure (GFR<60 ml/min) Magnetic metal parts in the body Ongoing treatment with selective serotonin receptor inhibitors
Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Basic Science
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Healthy control<br>Healthy control | Radiation: Positron emission tomography with the tracer [11C]5-hydroxy-tryptophan<br>* Estimation of islet mass by PET using the tracer [11C]5-hydroxy-tryptophan<br>|
| Experimental: Obese with oral antidiabetic drugs<br>BMI>30, Type 2 diabetes treated with oral antidiabetic drugs | Radiation: Positron emission tomography with the tracer [11C]5-hydroxy-tryptophan<br>* Estimation of islet mass by PET using the tracer [11C]5-hydroxy-tryptophan<br>|
| Experimental: Obese, treated with oral antidiabetic drugs + insulin<br>BMI>30, Type 2 diabetes treated with oral antidiabetic drugs + insulin | Radiation: Positron emission tomography with the tracer [11C]5-hydroxy-tryptophan<br>* Estimation of islet mass by PET using the tracer [11C]5-hydroxy-tryptophan<br>|
| Experimental: Normal weight, treated with oral antidiabetic drugs<br>BMI 20-26. Type 2 diabetes treated with oral antidiabetic drugs | Radiation: Positron emission tomography with the tracer [11C]5-hydroxy-tryptophan<br>* Estimation of islet mass by PET using the tracer [11C]5-hydroxy-tryptophan<br>|
| Experimental: Normal weight, treated with oral antidiabetic drugs + insulin<br>BMI 20-26. Type 2 diabetes treated with oral antidiabetic drugs + insulin | Radiation: Positron emission tomography with the tracer [11C]5-hydroxy-tryptophan<br>* Estimation of islet mass by PET using the tracer [11C]5-hydroxy-tryptophan<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| [11C]5-hydroxy-tryptophan Uptake in the Pancreas | Uptake of tracer with correlation to functional measurement with glucose-potentiated arginine stimulation of insulin release | Within two weeks after functional measurement with glucose potentiated arginine stimulation of insulin release | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pancreatic Perfusion | Uptake of radioactive water with correlation to functional measurement with glucose-potentiated arginine stimulation of insulin release | Within two weeks after functional measurement with glucose potentiated arginine stimulation of insulin release | 
| Pancreatic Volume |  | Within two weeks after functional measurement with glucose potentiated arginine stimulation of insulin release | 
| Pancreatic Fat Content |  | Within two weeks after functional measurement with glucose potentiated arginine stimulation of insulin release | 
| Hepatic Fat Content |  | Within two weeks after functional measurement with glucose potentiated arginine stimulation of insulin release |