Effects of Testosterone Gel on Carbohydrate and Lipid Metabolism In Elderly Obese Men
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|ClinicalTrials.gov Identifier: NCT00365794|
Recruitment Status : Completed
First Posted : August 17, 2006
Results First Posted : August 26, 2019
Last Update Posted : August 26, 2019
A. HYPOTHESES: In older men low testosterone levels, abdominal obesity and elevated fasting insulin who are at risk for the cardiovascular complications such as heart attack and stroke.
- Supplemental testosterone will decrease abdominal adipose tissue and hepatic fat) and appendicular fat and intramyocellular lipid in peripheral muscles (IMCL).
Supplemental testosterone will improve insulin sensitivity by:
- Decreasing hepatic glucose output (HGO), a measure of central insulin resistance
- increasing peipheral glucose disposal (Rd), a measure of periperal insuln sensiivity
- . Improving peripheral glucose disposal (Rd) by reducing IMCL
- Increasing appendicular skeletal muscle mass
- Primary Objective: To determine the effects of supplemental testosterone to achieve testosterone levels in the upper normal physiologic range on central adipose tissue (abdominal and hepatic fat) and peripheral skeletal muscle fat (appendicular fat and IMCL).
- Secondary Objectives: To determine the effects of supplemental testosterone to achieve testosterone levels in the upper normal physiologic range:on central insulin sensitivity ( hepatic glucose output ([HGO]) and peripheral insulin sensitivity (glucose disposal (Rd)
Results of this study will provide greater understanding whether androgen therapy enhances insulin sensitivity by decreasing HGO, improving peripheral Rd and if these desired effects are achieved, whether they are due to reductions in abdominal fat or liver lipid, IMCL or effects of augmenting muscle mass per se.
Results will generate hypotheses to investigate cellular and molecular mechanisms of androgen effects in persons at risk for the Metabolic Syndrome.
|Condition or disease||Intervention/treatment||Phase|
|Aging Obesity Insulin Resistance Hypogonadism||Drug: Topical testosterone gel 10 g/day||Phase 2|
Study Design: This is an investigator-initiated open label, study to investigate the effects of supplemental testosterone (gel formulation) to increase testosterone levels to the upper normal range in 12 older hypogonadal (testosterone levels less than 300 ng/dL) men with abdominal obesity and elevated fasting insulin levels. Subjects will be assigned to receive 10 g of transdermal testosterone (Androgel) every morning to achieve levels in the upper normal physiologic range (similar to men in the 3rd and 4th decades) for 20 weeks.
- For the primary objective, regional adipose tissue, namely DEXA measures of abdominal and appendicular fat mass and hepatic fat, and IMCL will be quantified by 1H-spectroscopy at baseline (study week 0) and at study week 20 (completion of study therapy).
- For the secondary objective, insulin sensitivity (peripheral Rd, hepatic glucose output [HGO]) and hepatic gluconeogenesis will be measured directly during a two stage hyperinsulinemic euglycemic clamp at baseline and study week 20.
- Indirect markers of lipid (adiponectin, ApoB 100) and carbohydrate metabolism (Fasting blood sugar, HOMA-IR) at study week 10, and study week 20.
All components of the study will be conducted in the USC NIH-funded (NCRR), General Clinical Research Center.
|Study Type :||Interventional (Clinical Trial)|
|Actual Enrollment :||22 participants|
|Intervention Model:||Single Group Assignment|
|Masking:||None (Open Label)|
|Masking Description:||No masking. This was an open label (un-blinded)|
|Official Title:||Investigator Initiated Study of the Effects of Androgen Therapy on Carbohydrate and Lipid Metabolism In Elderly Men|
|Study Start Date :||August 2006|
|Actual Primary Completion Date :||December 2013|
|Actual Study Completion Date :||December 2014|
Experimental: Single arm
Open label treatment without masking with each participant serving as his own control. Measurements are compared before and after treatment.
Drug: Topical testosterone gel 10 g/day
Testosterone gel therapy for 20 weeks
Other Name: Androgel
- Change in Total Mass and Regional Adipose Adiposiy [ Time Frame: Baseline to 20 weeks ]Change in total body mass, total fat mass, trunk fat, and extremity fat
- Change in Hepatic Lipid [ Time Frame: Baseline to week 20 ]Amount of liver fat is highly predictive of insulin resistance. Hepatic fat is measured by MR spectroscopy and adjusted for H2O and results are reported as ratio of these two.
- Intramyocellular Lipid (IMCL) [ Time Frame: Baseline to week 20 ]IMCL is quantified by MR spectroscopy of the anterior tibialis muscle of the leg. The value is adjusted for creatine and reported as a ratio
- Change in Percentage of Total Body Fat [ Time Frame: Baseline and 20 weeks ]Percentage of total body fat is quantified by DEXA scanning
- Change in Total and Regional Carbohydrate Metabolism During a 2-hr Hyperinsulinemic Euglycemic Clamp and [6,6-2H2] Glucose Studies (Peripheral Glucose Disposal [Rd],Hepatic Glucose Output [HGO]) [ Time Frame: Baseline and 20 weeks ]In the final analysis, total and regional carbohydrate metabolism during a 2-hr hyperinsulinemic euglycemic clamp (peripheral glucose disposal [Rd],hepatic glucose output [HGO]) were analyzed by mass transfer of glucose during both stages of the clamp relative to insulin levels.
- Change in Skeletal Muscle Mass by DEXA [ Time Frame: Baselne to 20 weeks ]Skeletal muscle mass was assesed by regional DEXA to quantify appendicular lean tissues which is primarily muscle.
- Plasma Lipids [ Time Frame: Baseline to week 20 ]
- Change in HOMA-IR [ Time Frame: Baseline to week 20 ]HOMA-IR is a measure of insulin resistance
- Change in Basal FFAs in Plasma [ Time Frame: Baseline to week 20 ]FFA (plasma free fatty acids) are measure of lipid metabolism
- Change in Plasma Free Fatty Acids During Glucose Clamp [ Time Frame: Baseline to 20 weeks ]
To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00365794
|United States, California|
|LAC-USC Medical Center GCRC|
|Los Angeles, California, United States, 90033|
|Principal Investigator:||Fred R Sattler, MD||University of Southern California|