The Effects of Growth Hormone (GH) on Lipid Depots
This study aims at investigating the effect of growth hormone on lipid-content of muscle and liver as well as visceral fat mass in relation to insulin sensitivity.
In addition, hormonal regulation and free fatty availability is assessed during a physical exercise at 50-60% VO2max.
Finally, the value of physical exercise in diagnosing growth hormone deficiency is investigated.
Hypothesis: 1) Lipid content of muscle and liver change with physical exercise and exercise capacity and free fatty availability will influence these changes. 2)Growth hormone replacement therapy will predominantly reduce visceral fat mass and increase free fatty availability.
3)Free fatty availability during exercise will be reduced in growth hormone deficient patients 4)Physical exercise may be an alternative way to diagnose growth hormone deficiency
|Growth Hormone Deficiency||Drug: Growth hormone replacement therapy in growth hormone deficient patients only.|
|Study Design:||Intervention Model: Single Group Assignment
Masking: Open Label
Primary Purpose: Basic Science
|Official Title:||The Effect of Growth Hormone (GH) on Intramyocellular Lipids (IMCL), Intrahepatocellular Lipids (IHCL) and Visceral Fat Mass in Relation to Insulin Resistance|
- Determination of visceral fat mass by MRI,Determination of IMCL and IHCL by MR Spectroscopy, Determination of peripheral and hepatic insulin sensitivity by two step hyperinsulinemic euglycemic clamp [ Time Frame: 2008 - 2009 ]
- maximal exercise capacity [ Time Frame: 2008 - 2009 ]
- Measurement of serum alphaKlothe by an ELISA [ Time Frame: 2008 - 2013 ]Measured in pg/mL
|Study Start Date:||July 2007|
|Study Completion Date:||June 2013|
|Primary Completion Date:||July 2009 (Final data collection date for primary outcome measure)|
No Intervention: Athletes, controls, patients
Sedentary controls: age, BMI, Gender and waist matched (to the growth hormone deficient patients) healthy control subjects Endurance trained athletes: minimal >50 mlO2/KG body weight
Drug: Growth hormone replacement therapy in growth hormone deficient patients only.
Genotropin once/daily sc., titration scheme according to the consensus guidelines of the GH and IGF-research society Duration: 6 months
Other Name: Genotropin
Using the two-step hyperinsulinaemic-euglycaemic clamp technique hepatic and peripheral insulin sensitivity is assessed.
Lipid depots (skeletal muscle and liver) are measured by MR-spectroscopy, visceral fat mass by MR-imaging.
Exercise capacity ist measured on a treadmill. Counterregulatory hormones, glucose and free fatty acids are measured during a 2h physical exercise at 50-60 VO2max Identical investigations are performed in adult growth hormone (GH) deficient patients before and after six months GH replacement therapy, in sedentary matched control subjects and in endurance trained athletes.
Please refer to this study by its ClinicalTrials.gov identifier: NCT00491582
|Abt. für Endokrinologie, Diabetologie und Klin. Ernährung, Inselspital|
|Bern, Switzerland, 3010|
|Principal Investigator:||Emanuel R Christ, Prof,MD,PhD||Abt. für Endokrinologie, Diabetologie und Klin. Ernährung, Inselspital, Berne|