The Effect of Administration of Small Doses of Thyroxine on Glucose and Lipid Metabolism, in Type 2 Diabetes Mellitus.
Study Details
Study Description
Brief Summary
We investigated the effect of the administration of small doses of thyroxine to healthy humans and patients with type 2 diabetes on postprandial forearm muscle glucose uptake, insulin sensitivity indices, lipid metabolism, in vitro glucose uptake and GLUT4 recruitment in the plasma membrane of monocytes.
| Condition or Disease | Intervention/Treatment | Phase |
|---|---|---|
|
N/A |
Detailed Description
The present open-labeled, randomized and placebo-controlled study was undertaken in euthyroid type 2 diabetic patients and healthy humans, to examine the effect of administration of small doses of thyroxine within the euthyroid range, on muscle glucose disposal, postprandial insulin sensitivity, lipid metabolism, in vitro glucose uptake and GLUT4 recruitment in the plasma membrane of monocytes.This was investigated with the arteriovenous-difference technique after the consumption of a mixed meal and the in vitro study of a glucose analogue(6-NBDG) uptake by the peripheral monocytes.
Subjects and Methods: Eleven euthyroid, treatment naive, type-2 diabetic patients with a micronodular texture of the thyroid gland and eleven healthy euthyroid subjects, were studied before and after administration of 50 μg of thyroxine once daily for 2 months. In parallel, a placebo group was also studied. Eleven euthyroid treatment-naïve subjects with type 2 diabetes and a micronodular texture of the thyroid gland, matched for age, sex, BMI, and basal thyroid function, were studied before and after administration of a placebo, once daily for 2 months.
Experimental protocol: All subjects were admitted to the hospital at 0700 h after an overnight fast and had the radial artery (A) and a forearm deep vein (V) catheterized. A meal (730kcal, 50%carbohydrate, of which 38% was starch, 40% fat, and 10% protein) was given at least 1 h after catheter insertion and was consumed within 20 min. Blood samples were drawn from both sites before the meal (at -30 and 0 min) and at 30- to 60-min intervals for 300 min thereafter for measurements of thyroid hormones,glucose, total cholesterol, LDL Cholesterol, HDL Cholesterol, triglycerides, Apolipoprotein A1, Apolipoprotein BII and Lp(a).Forearm blood flow was measured with strain-gauge plethysmography. After the first meal tolerance test, treatment with 50μg of thyroxine or placebo, once daily, was initiated for a 2-month period. Then a second identical test was repeated. Special care was taken in order to avoid the induction of subclinical hyperthyroidism, that is suppression of TSH below 0.27 μU/ml, as it has recently been shown that the latter is also an insulin-resistant condition.
Study Design
Arms and Interventions
| Arm | Intervention/Treatment |
|---|---|
| Active Comparator: thyroxine in eythyroid diabetics 50 μg of thyroxine once daily, for 2 months. |
Drug: thyroxine
treatment with 50μg of thyroxine once daily for two months.
Other Names:
Other: A meal (730kcal, 50%carbohydrate, of which 38% was starch, 40% fat, and 10% protein)
|
| Active Comparator: thyroxine in euthyroid healthy humans 50 μg of thyroxine once daily, for 2 months. |
Drug: thyroxine
treatment with 50μg of thyroxine once daily for two months.
Other Names:
Other: A meal (730kcal, 50%carbohydrate, of which 38% was starch, 40% fat, and 10% protein)
|
| Placebo Comparator: placebo in euthyroid diabetics 50 μg of placebo once daily, for 2 months. |
Drug: Placebo
treatment with 50μg of placebo, once daily, for two months.
Other: A meal (730kcal, 50%carbohydrate, of which 38% was starch, 40% fat, and 10% protein)
|
Outcome Measures
Primary Outcome Measures
- area under the glucose uptake versus time curve-AUC [Time Frame: 0, 30, 60, 90, 120, 180, 240, 300 min postmeal]
Muscle glucose uptake following meal ingestion
Secondary Outcome Measures
- Plasma glucose levels following meal ingestion [0, 30, 60, 90, 120, 180, 240, 300 min postmeal]
area under the plasma concentration versus time curve-AUC
- Plasma insulin levels following meal ingestion [0, 30, 60, 90, 120, 180, 240, 300 min postmeal]
area under the plasma concentration versus time curve-AUC
- Plasma triglyceride levels following meal ingestion [0, 30, 60, 90, 120, 180, 240, 300 min postmeal]
area under the plasma concentration versus time curve-AUC
- Plasma total cholesterol levels following meal ingestion [0, 30, 60, 90, 120, 180, 240, 300 min postmeal]
area under the plasma concentration versus time curve-AUC
- Plasma LDL-cholesterol levels following meal ingestion [0, 30, 60, 90, 120, 180, 240, 300 min postmeal]
area under the plasma concentration versus time curve-AUC
- Plasma HDL-cholesterol levels following meal ingestion [0, 30, 60, 90, 120, 180, 240, 300 min postmeal]
area under the plasma concentration versus time curve-AUC
- Plasma Apo-A levels following meal ingestion [0, 30, 60, 90, 120, 180, 240, 300 min postmeal]
area under the plasma concentration versus time curve-AUC
- Plasma Apo-B levels following meal ingestion [0, 30, 60, 90, 120, 180, 240, 300 min postmeal]
area under the plasma concentration versus time curve-AUC
- Plasma Lp(α) levels following meal ingestion [0, 30, 60, 90, 120, 180, 240, 300 min postmeal]
area under the plasma concentration versus time curve-AUC
- Plasma NEFA levels following meal ingestion [0, 30, 60, 90, 120, 180, 240, 300 min postmeal]
area under the plasma concentration versus time curve-AUC
- Plasma glycerol levels following meal ingestion [0, 30, 60, 90, 120, 180, 240, 300 min postmeal]
area under the plasma concentration versus time curve-AUC
- Muscle blood flow following meal ingestion [0, 30, 60, 90, 120, 180, 240, 300 min postmeal]
area under the plasma concentration versus time curve-AUC
- Plasma thyroid hormones [baseline]
measure of plasma concentration
- glucose uptake by peripheral monocytes by the usage of the fluorescent analogue 6-NBDG [baseline to 600 sec]
area under the curve of 6-NBDG uptake by monocytes under insulin stimulation
- % GLUT4 increment from baseline (0mU/l) to maximal concentration (200mU/l) of insulin. [baseline]
- Number of participants with adverse events [300 min postmeal]
Eligibility Criteria
Criteria
Inclusion Criteria:
-
Healthy or treatment naive type 2 diabetes euthyroid subjects, with a micronodular texture of the thyroid gland.
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Recreationally active
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With stable body weight and diet during the last two months.
Exclusion Criteria:
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Any systemic disease(besides glucose abnormalities)
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Any medication therapy
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Diabetic complications
Contacts and Locations
Locations
No locations specified.Sponsors and Collaborators
- Attikon Hospital
Investigators
- Study Director: GEORGE DIMITRIADIS, MD, Phd, 2nd Department of Internal Medicine, Research Institute and Diabetes Center, Athens University Medical School, Attikon Hospital
Study Documents (Full-Text)
None provided.More Information
Publications
None provided.- ΒΠΠΚ 50/11-02-09