Ignite Creation Date:
2024-05-05 @ 4:57 PM
Last Modification Date:
2024-10-26 @ 9:26 AM
Study NCT ID:
NCT00355784
Status:
COMPLETED
Last Update Posted:
2016-01-01
First Post:
2006-07-24
Brief Title:
Growth Hormone as a Determinant of Weight Regulation
Sponsor:
University of Michigan
Organization:
University of Michigan
Study Overview
Official Title:
Growth Hormone as a Determinant of Weight Regulation
Status:
COMPLETED
Status Verified Date:
2015-12
Last Known Status:
None
Delayed Posting:
No
If Stopped, Why?:
Not Stopped
Has Expanded Access:
False
If Expanded Access, NCT#:
N/A
Has Expanded Access, NCT# Status:
N/A
Acronym:
None
Brief Summary:
With the alarming increase in the prevalence of obesity identifying factors that predispose individuals to weight-gain is of critical importance Even when caloric intake and physical activity levels are well controlled susceptibility for weight-gain is heterogeneous Basal metabolic rate BMR represents the largest portion of daily energy expenditure in normal adults and as such variability in BMR among individuals can be a major factor in determining the susceptibility for gaining weight However factors responsible for this variability in BMR and resistance to weight-gain remain unclear Our preliminary data indicate that high-normal growth hormone GH concentration is associated with resistance to weight-gain in rats when overfed and greater weight-loss in humans when underfed In addition the investigators have found that the pulsatility of GH secretion has profound effects on several metabolic processes Therefore together these findings suggest that endogenous GH secretion is associated with body weight regulation and the pulsatility peak amplitude of GH secretion rather than the absolute GH concentration per se may be responsible for this effect Because GH influences many of the key metabolic processes that contribute to BMR eg protein synthesis proteolysis substrate cycling the investigators anticipate that the resistance to weight-gain in persons with elevated GH concentrations will be associated with an increase in BMR due to acceleration of some or all of these processes Our overall hypothesis is that increased GH secretion can protect against weight-gain due to an augmentation of major metabolic processes that contribute to BMR Identifying factors responsible for predisposing individuals to weight-gain will lead to establishing improved methods for reducing the prevalence of obesity
Detailed Description:
The susceptibility to gain weight is highly variable even when caloric intake and physical activity are well controlled Because basal metabolic rate BMR represents 70 of total daily energy expenditure TDEE even a small difference in BMR can affect daily energy balance thereby increasing the susceptibility for gaining weight Our preliminary data indicate that high-normal growth hormone GH secretion is associated with resistance to weight-gain in rats when overfed and greater weight-loss in humans when underfed Given that GH influences many of the key metabolic processes that contribute to BMR the investigators hypothesize that persons with high-normal GH will be resistant to weight-gain because of a high BMR resulting from accelerated rates of these processes The investigators will measure basal 24h GH secretion and BMR in 106 non-obese men and women The investigators will also measure protein synthesis proteolysis triglyceridefatty acid cycling all measured using stable isotope tracer methods to determine the relationships among these processes BMR and GH Specific Aim 1 Subjects identified as having low-normal 15 ugL and high-normal 3 ugL 24h GH will then be admitted to the hospital for a 2 wk overfeeding protocol 2000 kcald TDEE - with restricted physical activity immediately followed by a 4 wk caloric restriction protocol 750 kcald TDEE to compare changes in weight body composition and intra-abdominal adiposity between these groups that differ markedly in their GH secretion GH measured before the diet Specific Aim 2 A subset of subjects with low-normal GH will receive intravenous GH throughout the 2 wk overfeeding period at either 1 a constant rate or 2 as a pulsatile infusion to mimic endogenous secretion BMR will be assessed daily and protein synthesis proteolysis and triglyceridefatty acid cycling will be measured at the end of the 2 wks Specific Aim 3 The investigators anticipate that a higher GH pulsatility peak amplitude rather than elevated GH concentration per se will increase protein synthesis proteolysis and triglyceridefatty acid cycling with a resultant increase in BMR and resistance to weight-gain Identifying factors responsible for predisposing individuals to weight-gain will help combat the alarming rise in the prevalence of obesity
Study Oversight
Has Oversight DMC:
None
Is a FDA Regulated Drug?:
None
Is a FDA Regulated Device?:
None
Is an Unapproved Device?:
None
Is a PPSD?:
None
Is a US Export?:
None
Is an FDA AA801 Violation?:
None
Secondary IDs
| Secondary ID | Type | Domain | Link |
|---|---|---|---|
| R01DK071955 | NIH | None | httpsreporternihgovquickSearchR01DK071955 |