| 1. |
- Allen, David B, et al.
(författare)
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GH Safety Workshop Position Paper: a critical appraisal of recombinant human growth hormone therapy in children and adults.
- 2016
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Ingår i: European Journal of Endocrinology. - 1479-683X. ; 174:2, s. 1-9
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Tidskriftsartikel (refereegranskat)abstract
- Recombinant human growth hormone (rhGH) has been in use for 30 years, and over that time its safety and efficacy in children and adults has been subject to considerable scrutiny. In 2001, a statement from the GH Research Society (GRS) concluded that 'for approved indications, GH is safe'; however, the statement highlighted a number of areas for on-going surveillance of long-term safety including; cancer risk, impact on glucose homeostasis and use of high dose pharmacological rhGH treatment. Over the intervening years, there have been a number of publications addressing the safety of rhGH with regard to mortality, cancer and cardiovascular risk and the need for longterm surveillance of the increasing number of adults who were treated with rhGH in childhood. Against this backdrop of interest in safety, the European Society of Paediatric Endocrinology (ESPE), the GRS and the Pediatric Endocrine Society (PES) convened a meeting to reappraise the safety of rhGH. The ouput of the meeting is a concise position statement.
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| 2. |
- Birzniece, Vita, et al.
(författare)
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Modulatory effect of raloxifene and estrogen on the metabolic action of growth hormone in hypopituitary women.
- 2010
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Ingår i: The Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 1945-7197 .- 0021-972X. ; 95:5, s. 2099-106
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Tidskriftsartikel (refereegranskat)abstract
- The metabolic action of GH is attenuated by estrogens administered via the oral route. Selective estrogen receptor modulators lower IGF-I to a lesser degree than 17beta-estradiol in GH-deficient women, and their effect on fat and protein metabolism is unknown.
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| 3. |
- Burt, Morton G, et al.
(författare)
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Impact of acute and chronic low-dose glucocorticoids on protein metabolism.
- 2007
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Ingår i: The Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 0021-972X .- 1945-7197. ; 92:10, s. 3923-9
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Tidskriftsartikel (refereegranskat)abstract
- CONTEXT: High-dose glucocorticoids cause acute protein loss by increasing protein breakdown and oxidation. Whether lower glucocorticoid doses, typical of therapeutic use, induce sustained catabolism has not been studied. OBJECTIVE: Our objective was to assess the effect of acute and chronic therapeutic glucocorticoid doses on protein metabolism. DESIGN AND SETTING: We conducted an open longitudinal and a cross-sectional study at a clinical research facility. PATIENTS AND INTERVENTION: Ten healthy subjects were studied before and after a short course of prednisolone (5 and 10 mg/d sequentially for 7 d each). Twelve subjects with inactive polymyalgia rheumatica receiving chronic (>12 months) prednisone (mean = 5.0 +/- 0.8 mg/d) were compared with 12 age- and gender-matched normal subjects. MAIN OUTCOME MEASURE: Whole-body protein metabolism was assessed using a 3-h primed constant infusion of 1-[(13)C]leucine, from which rates of leucine appearance (leucine Ra, an index of protein breakdown), leucine oxidation (Lox, index of protein oxidation) and leucine incorporation into protein (LIP, index of protein synthesis) were estimated. RESULTS: Prednisolone induced an acute significant increase in Lox (P = 0.008) and a fall in LIP (P = 0.08) but did not affect leucine Ra. There was no significant difference between the effects of the 5- and 10-mg prednisolone doses on leucine metabolism. In subjects receiving chronic prednisone therapy, leucine Ra, Lox, and LIP were not significantly different from normal subjects. CONCLUSION: Glucocorticoids stimulate protein oxidation after acute but not chronic administration. This time-related change suggests that glucocorticoid-induced stimulation of protein oxidation does not persist but that a metabolic adaptation occurs to limit protein loss.
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| 4. |
- Burt, Morton G, et al.
(författare)
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Impact of growth hormone and dehydroepiandrosterone on protein metabolism in glucocorticoid-treated patients.
- 2008
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Ingår i: The Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 0021-972X .- 1945-7197. ; 93:3, s. 688-95
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Tidskriftsartikel (refereegranskat)abstract
- CONTEXT: Chronic pharmacological glucocorticoid (GC) use causes substantial morbidity from protein wasting. GH and androgens are anabolic agents that may potentially reverse GC-induced protein loss. OBJECTIVE: Our objective was to assess the effect of GH and dehydroepiandrosterone (DHEA) on protein metabolism in subjects on long-term GC therapy. DESIGN: This was an open, stepwise GH dose-finding study (study 1), followed by a randomized cross-over intervention study (study 2). SETTING: The studies were performed at a clinical research facility. PATIENTS AND INTERVENTION: In study 1, six subjects (age 69+/-4 yr) treated with long-term (>6 months) GCs (prednisone dose 8.3+/-0.8 mg/d) were studied before and after two sequential GH doses (0.8 and 1.6 mg/d) for 2 wk each. In study 2, 10 women (age 71+/-3 yr) treated with long-term GCs (prednisone dose 5.4+/-0.5 mg/d) were studied at baseline and after 2-wk treatment with GH 0.8 mg/d, DHEA 50 mg/d, or GH and DHEA (combination treatment). MAIN OUTCOME MEASURE: Changes in whole body protein metabolism were assessed using a 3-h primed constant infusion of 1-[13C]leucine, from which rates of leucine appearance, leucine oxidation, and leucine incorporation into protein were estimated. RESULTS: In study 1, GH 0.8 and 1.6 mg/d significantly reduced leucine oxidation by 19% (P=0.03) and 31% (P=0.02), and increased leucine incorporation into protein by 10% (P=0.13) and 19% (P=0.04), respectively. The lower GH dose did not cause hyperglycemia, whereas GH 1.6 mg/d resulted in fasting hyperglycemia in two of six subjects. In study 2, DHEA did not significantly change leucine metabolism alone or when combined with GH. Blood glucose was not affected by DHEA. CONCLUSION: GH, at a modest supraphysiological dose of 0.8 mg/d, induces protein anabolism in chronic GC users without causing diabetes. DHEA 50 mg/d does not enhance the effect of GH. GH may safely prevent or reverse protein loss induced by chronic GC therapy.
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| 5. |
- Gibney, James, et al.
(författare)
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Comparison of the metabolic effects of raloxifene and oral estrogen in postmenopausal and growth hormone-deficient women.
- 2005
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Ingår i: The Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 0021-972X .- 1945-7197. ; 90:7, s. 3897-903
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Tidskriftsartikel (refereegranskat)abstract
- CONTEXT: The endocrine and metabolic functions of the liver are affected by estrogen. Oral estrogen reduces IGF-I and suppresses fat oxidation despite augmenting GH secretion. The aim of this study was to determine whether selective estrogen receptor modulators display similar effects and whether these effects are magnified in GH-deficient (GHD) women because of the loss of GH feedback. DESIGN: This was an open-label, randomized, two-period, crossover study comparing treatment (raloxifene vs. estradiol) and group (normal vs. GHD). SETTING: The setting of this study was a clinical research unit. PARTICIPANTS: Twelve postmenopausal women and 12 women with hypopituitarism participated in this study. INTERVENTION: Two 4-wk treatments with 17beta-estradiol (E2; 2 mg, followed by 4 mg) or raloxifene (60 mg, followed by 120 mg) were given, crossing over to the alternate treatment after a 4-wk washout period. OUTCOME MEASURES: Endocrine [GH, IGF-I, IGF-binding protein-3 (IGFBP-3), GH-binding protein, and SHBG] and metabolic (fat oxidation) end points were used as outcome measures. RESULTS: E2 reduced serum IGF-I levels in a dose-dependent manner in both groups, with effects greater (P < 0.05) than raloxifene. Raloxifene reduced IGF-I levels in the GHD group (P < 0.001), but not in the postmenopausal group. E2 reduced (P < 0.05), and raloxifene increased (P < 0.05), IGFBP-3 levels in both groups. E2, but not raloxifene, increased GH (P < 0.05) in postmenopausal women. The effects of E2 and raloxifene on IGF-I, IGFBP-3, IGF-I/IGFBP-3 molar ratio, GH-binding protein, and SHBG were significantly different (P < 0.05). E2 and raloxifene reduced (P < 0.05) fat oxidation equally in GHD, whereas the decrease in postmenopausal women was not significant. CONCLUSION: E2 and raloxifene exert different hepatic endocrine, but not lipid oxidative, effects. The greater effects seen in GHD women may be explained by the loss of endogenous GH feedback.
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| 6. |
- Gibney, James, et al.
(författare)
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Growth hormone and testosterone interact positively to enhance protein and energy metabolism in hypopituitary men.
- 2005
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Ingår i: American journal of physiology. Endocrinology and metabolism. - : American Physiological Society. - 0193-1849 .- 1522-1555. ; 289:2
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Tidskriftsartikel (refereegranskat)abstract
- We investigated the impact of growth hormone (GH) alone, testosterone (T) alone, and combined GH and T on whole body protein metabolism. Twelve hypopituitary men participated in two studies. Study 1 compared the effects of GH alone with GH plus T, and study 2 compared the effects of T alone with GH plus T. IGF-I, resting energy expenditure (REE), and fat oxidation (F(ox)) and rates of whole body leucine appearance (R(a)), oxidation (L(ox)), and nonoxidative leucine disposal (NOLD) were measured. In study 1, GH treatment increased mean plasma IGF-I (P < 0.001). GH did not change leucine R(a) but reduced L(ox) (P < 0.02) and increased NOLD (P < 0.02). Addition of T resulted in an additional increase in IGF-I (P < 0.05), reduction in Lox (P < 0.002), and increase in NOLD (P < 0.002). In study 2, T alone did not alter IGF-I levels. T alone did not change leucine R(a) but reduced L(ox) (P < 0.01) and increased NOLD (P < 0.01). Addition of GH further reduced L(ox) (P < 0.05) and increased NOLD (P < 0.05). In both studies, combined treatments on REE and F(ox) were greater than either alone. In summary, GH-induced increase of circulating IGF-I is augmented by T, which does not increase IGF-I in the absence of GH. T and GH exerted independent and additive effects on protein metabolism, F(ox) and REE. The anabolic effects of T are independent of circulating IGF-I.
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| 7. |
- Ho, Ken K Y, et al.
(författare)
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Regulating of growth hormone sensitivity by sex steroids: implications for therapy.
- 2006
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Ingår i: Frontiers of hormone research. - Basel : KARGER. - 0301-3073. ; 35, s. 115-28
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Tidskriftsartikel (refereegranskat)abstract
- Growth hormone (GH) is an important regulator of body composition, reducing body fat by stimulating fat oxidation and enhancing lean body mass by stimulating protein accretion. The emergence of differences in body composition between the sexes during puberty suggests sex steroids modulate the action of GH. Work from our laboratory have investigated the influence of estrogens and androgens on the metabolic actions of GH in human adults. The liver is an important site of physiological interaction as it is a sex steroid responsive organ and a major target of GH action. Estrogen, when administered orally impairs the GH-regulated endocrine and metabolic function of the liver via a first-pass effect. It reduces circulating IGF-I, fat oxidation and protein synthesis, contributing to a loss of lean and a gain of fat mass. These effects occur in normal and in GH-deficient women and are avoided by transdermal administration of physiological doses of estrogen. In contrast, studies in hypopituitary men indicate that testosterone enhances the metabolic effects of GH. Testosterone alone stimulates fat oxidation and protein synthesis, both of which are enhanced by GH. Studies in GH deficiency adults have consistently reported women to be less sensitive to GH than men. In summary, estrogens and androgens exert divergent effects on the action of GH. The results provide an explanation for sexual dimorphism in body composition in adults and the gender-related response to GH replacement in hypopituitary subjects. In the management of hypopituitarism, estrogens should be administered by the parenteral route in women and testosterone be replaced in men to optimize the benefits of GH replacement.
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| 8. |
- Johannsson, Gudmundur, 1960, et al.
(författare)
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Independent and combined effects of testosterone and growth hormone on extracellular water in hypopituitary men.
- 2005
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Ingår i: The Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 0021-972X .- 1945-7197. ; 90:7, s. 3989-94
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Tidskriftsartikel (refereegranskat)abstract
- CONTEXT: Symptoms of fluid retention in GH-deficient patients during GH replacement are greater in men than in women, suggesting that testosterone may augment or estradiol may attenuate the antinatriuretic actions of GH. The mechanisms underlying the sodium-retaining effects of GH are poorly understood. AIM: The aim of this study was to investigate the effects of GH and testosterone, alone and in combination, on extracellular water (ECW) and the hormonal mechanisms involved. DESIGN: Two separate, open-label, randomized, two-period, crossover studies were performed; the first compared the effects of GH alone with those of GH and testosterone, and the second compared the effects of testosterone alone with those of GH and testosterone. PARTICIPANTS: Twelve hypopituitary men with GH deficiency and hypogonadism were studied. INTERVENTION: During the weeks of intervention, GH (0.5 mg/d) and testosterone enanthate (250 mg) were administered by im injection. OUTCOME MEASURES: The outcome measures were ECW, IGF-I, plasma renin activity (PRA), aldosterone (Aldo), and atrial natriuretic peptide (ANP). RESULTS: GH treatment significantly increased (P < 0.05) both IGF-I and ECW, and these changes were enhanced by cotreatment with testosterone (P = 0.07 for both). PRA, Aldo, and ANP levels did not change. Testosterone treatment alone did not change the IGF-I concentration, whereas cotreatment with GH induced a marked increase. Testosterone alone increased (P < 0.05) ECW, and the effect was augmented (P < 0.01) by cotreatment with GH. Although PRA and ANP did not change, plasma Aldo decreased after single and combined treatments. CONCLUSION: GH and testosterone exerted independent and additive effects on ECW. The mechanisms of fluid retention for both hormones are likely to be exerted on the renal tubules. This is the first direct evidence that testosterone increases ECW.
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| 9. |
- Leung, Kin-Chuen, et al.
(författare)
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Estrogen regulation of growth hormone action.
- 2004
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Ingår i: Endocrine reviews. - : The Endocrine Society. - 0163-769X .- 1945-7189. ; 25:5, s. 693-721
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Tidskriftsartikel (refereegranskat)abstract
- GH plays a pivotal role in regulating body growth and development, which is modulated by sex steroids. A close interplay between estrogen and GH leads to attainment of gender-specific body composition during puberty. The physiological basis of the interaction is not well understood. Most previous studies have focused on the effects of estrogen on GH secretion. There is also strong evidence that estrogen modulates GH action independent of secretion. Oral but not transdermal administration of estrogen impairs the metabolic action of GH in the liver, causing a fall in IGF-I production and fat oxidation. This results in a loss of lean tissue and a gain of body fat in postmenopausal women and an impairment of GH effect in hypopituitary women on GH replacement. The negative metabolic sequelae are potentially important because of the widespread use of oral estrogen and estrogen-related compounds. Estrogen affects GH action at the level of receptor expression and signaling. More recently, estrogen has been shown to inhibit Janus kinase/signal transducer and activator of transcription signaling by GH via the induction of suppressor of cytokine signaling-2, a protein inhibitor for cytokine signaling. This represents a novel paradigm of steroid regulation of cytokine receptors and is likely to have significance for a diverse range of cytokine function.
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| 10. |
- Ragnarsson, Oskar, 1971, et al.
(författare)
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Effect of short-term growth hormone and testosterone administration on body composition and glucose homeostasis in men receiving chronic glucocorticoid therapy.
- 2013
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Ingår i: European journal of endocrinology / European Federation of Endocrine Societies. - 1479-683X. ; 168:2, s. 243-51
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Long-term pharmacological glucocorticoid (GC) therapy leads to skeletal muscle atrophy and weakness. The objective of this study was to investigate whether short-term treatment with growth hormone (GH) and testosterone (T) can increase lean mass without major impairment of glucose homeostasis in patients on GC therapy. DESIGN, MATERIALS AND METHODS: This was a prospective, open-label, randomized, crossover study. Twelve men (age 74±6 years) on chronic GC treatment participated. The effects of two weeks treatment with GH, testosterone and the combination of both, on lean body mass (LBM), appendicular skeletal muscle mass (ASMM), extracellular water (ECW), body cell mass (BCM) and plasma glucose concentrations were investigated. RESULTS: LBM increased significantly after GH (Δ1.7±1.4 kg; P=0.007) and GH+T (Δ2.4±1.1 kg; P=0.003), but not T alone. ASMM increased after all three treatment periods; by 1.0±0.8 kg after GH (P=0.005), 1.7±0.4 kg after GH+T (P=0.002) and 0.8±1.0 kg after T (P=0.018). The increase in ASMM was larger with combined treatment than either GH or T alone (P<0.05). ECW increased significantly after GH+T by 1.5±2.6 L (P=0.038) but not after GH or T alone. BCM increased slightly after single and combined treatments but the changes were not significant. Fasting glucose increased significantly after GH (Δ0.4±0.4 mmol/L, P=0.006) while both fasting (Δ0.2±0.3 mmol/L, P=0.045) and post glucose-load (Δ1.8±2.3 mmol/L, P=0.023) plasma glucose concentrations increased after GH+T. CONCLUSIONS: GH and T induce favourable and additive body compositional changes in men on chronic, low-dose GC treatment. In the doses used, combination therapy increases fasting and postprandial glucose concentration.
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