Growth Hormone Improve Body Composition Research Articles

Testosterone and Growth Hormone Improve Body Composition and Muscle Performance in Older Men

Testosterone and Growth Hormone Improve Body Composition and Muscle Performance in Older Men

Testosterone and Growth Hormone Improve Body Composition and Muscle Performance in Older Men

Testosterone and Growth Hormone Improve Body Composition and Muscle Performance in Older Men

Testosterone and Growth Hormone Improve Body Composition and Muscle Performance in Older Men

Testosterone and Growth Hormone Improve Body Composition and Muscle Performance in Older Men

Testosterone and growth hormone in older men: for better or for worse?

Evaluation of: Sattler FR, Castaneda-Sceppa C, Binder EF et al. Testosterone and growth hormone improve body composition and muscle performance in older men. J. Clin. Endocrinol. Metab. 94(6), 1991–2001 (2009).In men, testosterone and IGF1 levels decline with increasing age, and lower levels of these hormones are associated with poorer health. A recent, randomized clinical trial demonstrates the additive effects of testosterone and growth hormone supplementation to increase lean body mass, reduce fat mass and improve muscle strength in older men. These findings highlight the interaction between these two hormones and provide a model for further evaluation of combined therapy to explore other end points, such as cardiovascular risk.

Growth hormone improves body composition, fasting blood glucose, glucose tolerance and liver triacylglycerol in a mouse model of diet-induced obesity and type 2 diabetes

Growth hormone has been used experimentally in two studies to treat individuals with type 2 diabetes, with both reporting beneficial effects on glucose metabolism. However, concerns over potential diabetogenic actions of growth hormone complicate its anticipated use to treat type 2 diabetes. Thus, an animal model of type 2 diabetes could help evaluate the effects of growth hormone for treating this condition. Male C57BL/6J mice were placed on a high-fat diet to induce obesity and type 2 diabetes. Starting at 16 weeks of age, mice were treated once daily for 6 weeks with one of four different doses of growth hormone. Body weight, body composition, fasting blood glucose, insulin, glucose tolerance, liver triacylglycerol, tissue weights and blood chemistries were determined. Body composition measurements revealed a dose-dependent decrease in fat and an increase in lean mass. Analysis of fat loss by depot revealed that subcutaneous and mesenteric fat was the most sensitive to growth hormone treatment. In addition, growth hormone treatment resulted in improvement in glucose metabolism, with the highest dose normalising glucose, glucose tolerance and liver triacylglycerol. In contrast, insulin levels were not altered by the treatment, nor did organ weights change. However, fasting plasma leptin and resistin were significantly decreased after growth hormone treatment. Growth hormone therapy improves glucose metabolism in this mouse model of obesity and type 2 diabetes, providing a means to explore the molecular mechanism(s) of this treatment.

Testosterone and Growth Hormone Improve Body Composition and Muscle Performance in Older Men

Impairments in the pituitary-gonadal axis with aging are associated with loss of muscle mass and function and accumulation of upper body fat. We tested the hypothesis that physiological supplementation with testosterone and GH together improves body composition and muscle performance in older men. One hundred twenty-two community-dwelling men 70.8 +/- 4.2 yr of age with body mass index of 27.4 +/- 3.4 kg/m2, testosterone of 550 ng/dl or less, and IGF-I in lower adult tertile (< or =167 ng/dl) were randomized to receive transdermal testosterone (5 or 10 g/d) during a Leydig cell clamp plus GH (0, 3, or 5 microg/kg . d) for 16 wk. Body composition by dual-energy x-ray absorptiometry, muscle performance, and safety tests were conducted. Total lean body mass increased (1.0 +/- 1.7 to 3.0 +/- 2.2 kg) as did appendicular lean tissue (0.4 +/- 1.4 to 1.5 +/- 1.3 kg), whereas total fat mass decreased by 0.4 +/- 0.9 to 2.3 +/- 1.7 kg as did trunk fat (0.5 +/- 0.9 to 1.5 +/- 1.0 kg) across the six treatment groups and by dose levels for each parameter (P < or = 0.0004 for linear trend). Composite maximum voluntary strength of upper and lower body muscles increased by 14 +/- 34 to 35 +/- 31% (P < 0.003 in the three highest dose groups) that correlated with changes in appendicular lean mass. Aerobic endurance increased in all six groups (average 96 +/- 137 sec longer). Systolic and diastolic blood pressure increased similarly in each group with mean increases of 12 +/- 14 and 8 +/- 8 mm Hg, respectively. Other predictable adverse events were modest and reversible. Supplemental testosterone produced significant gains in total and appendicular lean mass, muscle strength, and aerobic endurance with significant reductions in whole-body and trunk fat. Outcomes appeared to be further enhanced with GH supplementation.

Does low-dose growth hormone therapy improve the body composition of patients infected with HIV?

Use of highly active antiretroviral therapy in patients infected with HIV can lead to lipodystrophy, a condition characterized by changes in body-fat distribution. In addition, infected individuals often exhibit relative growth hormone (GH) deficiency. Treatment with supraphysiological levels of GH improves body composition in these patients, but is associated with adverse effects. In this Practice Point commentary, we discuss an 18-month, randomized, double-blind, placebo-controlled study of low-dose GH therapy in 56 HIV-positive adults with lipodystrophy and relative GH deficiency. Lo et al. found that administration of low-dose GH (mean 0.33 mg daily) led to improvements in body composition (e.g. visceral adipose-tissue area), diastolic blood pressure and triglyceride levels. Furthermore, this treatment regimen was not associated with an increased incidence of adverse events compared with placebo. Here, we discuss the implications of the findings of Lo et al., and describe additional strategies that might be used to treat lipodystrophy in HIV-positive individuals.

Growth hormone improves body composition, fat utilization, physical strength and agility, and growth in Prader-Willi syndrome: A controlled study

Background: Obesity and hypotonia in children with Prader-Willi syndrome (PWS) are accompanied by abnormal body composition and diminished energy expenditure resembling a growth hormone–deficient state. Hypothalamic dysfunction in PWS often includes decreased growth hormone (GH) secretion, suggesting a possible therapeutic role for exogenous GH treatment. Objectives and methods: After 6 months of observation to determine baseline growth rate, and with the use of a 12-month randomized controlled study design, the effects of GH treatment (1 mg/m 2/d) on growth, body composition, strength and agility, pulmonary function, resting energy expenditure (REE), and fat utilization were assessed in 54 children with PWS (n = 35 treatment and n = 19 control). Percent body fat and bone mineral density were measured by dual x-ray absorptiometry. Indirect calorimetry was used to determine REE and to calculate respiratory quotients. Results: Stimulated levels of GH in response to clonidine testing were low in all patients (peak, 2.0 ng/mL). After 12 months, GH-treated subjects showed significantly increased height velocity Z scores (mean, –1.0 ± 1.7 to 4.6 ± 2.9; P < .001), decreased percent body fat (mean, 46.3% ± 8.4% to 38.3% ± 10.7%; P < .001), and improved respiratory muscle function, physical strength, and agility (sit-ups, weight-lifts, running speed, and coordination). A significant decline in respiratory quotients occurred during GH therapy (0.81 to 0.77, P < .001), but total REE did not change. Conclusions: GH treatment of children with PWS accelerated growth, decreased percent body fat, and increased fat oxidation but did not significantly increase total REE. Improvements in respiratory muscle strength, physical strength, and agility also occurred, suggesting that GH treatment may have value in reducing some physical disabilities experienced by children with PWS. (J Pediatr 1999;134:215-21)

Growth Hormone Improves Body Composition and Physical Agility without Altering Energy Expenditure in Children with Prader-Willi Syndrome † 395

Growth Hormone Improves Body Composition and Physical Agility without Altering Energy Expenditure in Children with Prader-Willi Syndrome † 395