Growth hormone administration stimulates energy expenditure and extrathyroidal conversion of thyroxine to triiodothyronine in a dose‐dependent manner and suppresses circadian thyrotrophin levels: studies in GH‐deficient adults

Jørgensen, Jens Otto Lunde; Møller, Jens Kjølseth; Laursen, Torben; Ørskov, Hans; Js, Christiansen; Weeke, Jørgen

doi:10.1111/j.1365-2265.1994.tb01826.x

Cited by 152 publications

(107 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Indeed, in patients with CeH, serum FT 3 levels were higher in subjects with GH replacement therapy than those without it in our study. Coexisting GHD might decrease serum FT 3 levels because of decreased deiodinase acivity (20,21). Furthermore, it is well known that high-dose glucocorticoid replacement therapy inhibits deiodinase activity (12,13).…”

Section: Discussionmentioning

confidence: 99%

Median-lower normal levels of serum thyroxine are associated with low triiodothyronine levels and body temperature in patients with central hypothyroidism

Hirata

Fukuoka

Iguchi

et al. 2015

European Journal of Endocrinology

View full text Add to dashboard Cite

Objective: Although it has been recommended that serum free thyroxine (FT 4 ) levels should be targeted to middle-upper normal levels during levothyroxine (L-T 4 ) replacement therapy in patients with central hypothyroidism (CeH), the rationale has not been clarified. Methods: A retrospective single-center study enrolled 116 patients with hypothyroidism (CeH, nZ32; total thyroidectomy (Tx), nZ22; primary hypothyroidism (PH), nZ33; and control benign thyroid nodule (C), nZ29). The patients had received L-T 4 therapy at the Kobe University Hospital between 2003 and 2013. They were stratified according to serum FT 4 level (R1.10 or !1.10 ng/dl), and body temperature (BT), serum free triiodothyronine (FT 3 ) levels, FT 3 /FT 4 ratio, and lipid profiles were compared. The effect of GH replacement therapy on thyroid function was also analyzed. Results: FT 3 levels and FT 3 /FT 4 ratios were significantly lower in patients with CeH than in patients with PH (P!0.05) or C (P!0.05). In patients with FT 4 !1.10 ng/dl, BT was significantly lower in patients with CeH (PZ0.002) and Tx (PZ0.005) than in patients with PH, whereas no differences were found in patients with FT 4 R1.10 ng/dl. In patients with CeH, FT 3 levels were higher in those with GH replacement therapy (PZ0.018). Conclusion: In CeH, patients with median-lower normal levels of serum FT 4 exhibited lower serum FT 3 levels and lower BT. These results support the target levels of serum FT 4 as middle-upper normal levels during L-T 4 replacement therapy in patients with CeH.

show abstract

Section: Discussionmentioning

confidence: 99%

Median-lower normal levels of serum thyroxine are associated with low triiodothyronine levels and body temperature in patients with central hypothyroidism

Hirata

Fukuoka

Iguchi

et al. 2015

European Journal of Endocrinology

View full text Add to dashboard Cite

show abstract

“…GH treatment has been found to increase REE in adult patients with GH de®ciency. 15,30,31 In one study 15 the increase in REE was positively correlated with the increase in T3 serum levels, caused by the GH-induced peripheral conversion of T4 to T3 itself. A signi®cant increase in REE, recognizable even when REE was corrected for LBM and not correlated with thyroid hormone concentrations, was also observed in obese women treated with rhGH for ®ve weeks but not following a hypocaloric diet.…”

Section: Discussionmentioning

confidence: 99%

“…13 In addition, GH administration to GH-de®cient adults is associated with an increase in REE, likely through the enhancement of peripheral conversion of thyroxine (T4) to triiodothyronine (T3). 14,15 GH treatment was also found capable of increasing serum markers of bone turnover in normal volunteers 16 and GH-de®-cient adults 17 and, in the latter, bone mineral density in the long term. 17 A decrease in plasma leptin concentrations has been described in obese patients after diet-induced weight loss 18 and in GH-de®cient adults after GH substitution therapy.…”

Section: Introductionmentioning

confidence: 97%

Metabolic effects of biosynthetic growth hormone treatment in severely energy-restricted obese women

et al. 1998

View full text Add to dashboard Cite

OBJECTIVE: Severe energy restriction in the treatment of obesity is limited by catabolism of body protein stores and, consequently, loss of lean as well as fat tissue. Growth hormone (GH), whose secretion is markedly impaired in obesity, is endowed with both lipolytic and protein anabolic properties. The aim of this study was to verify the effects of GH administration on body composition, plasma leptin levels and energy metabolism in obese patients undergoing severe dietary restriction. DESIGN: Single-blind placebo-controlled study. Twenty obese women were fed a diet of 41.86 kJ/kg ideal body weight (IBW) daily for 4 weeks: 10 of them were randomly assigned to a 4 week treatment with biosynthetic GH (rhGH, Saizen, Serono, Rome, Italy), 1 U/kg IBW/week in daily subcutaneous injections; the other 10 patients, matched for age and BMI, received vehicle only. SUBJECTS: Twenty women with simple obesity (age: 25.4 AE 1.07 y, BMI: 35.9 AE 0.35 kg/m 2 ). MEASUREMENTS: Plasma IGF-I and leptin, serum markers of bone turnover (serum bone isoenzyme of alkaline phosphatase, osteocalcin and urinary hydroxyproline), nitrogen balance, body composition (by DEXA), and resting energy expenditure (REE, by indirect calorimetry) were evaluated at baseline and after 4 weeks. RESULTS: Mean IGF-I plasma levels, not in¯uenced by energy restriction in patients receiving placebo, displayed a signi®cant increase in the group treated with rhGH. The mean weight reduction and fat mass loss were not signi®cantly different in the two groups (6.0 AE 0.51 vs 7.2 AE 0.30 kg, NS, and 5.36 AE 0.460 vs 4.28 AE 0.572 kg, NS, with rhGH and placebo, respectively). Likewise, plasma leptin levels decreased signi®cantly in weight-reduced subjects receiving either rhGH (from 16.2 AE 2.37 to 6.4 AE 0.39 ng/ml, P`0.05) or placebo (from 14.3 AE 2.55 to 7.7 AE 3.77 ng/ml, P`0.05). On the contrary, the mean decrease of lean body mass (LBM) was signi®cantly lower in the GH-treated patients than in those receiving vehicle (1.52 AE 0.60 vs 3.79 AE 0.45 kg, P`0.05). In keeping with these ®ndings, the mean daily nitrogen balance was signi®cantly less negative in the GH-treated subjects than in the vehicle-injected patients (mean of the 4 week daily urine collections 7185.7 AE 40.33 vs 7363.9 AE 55.47 mmol/d, P`0.05, respectively). Further, a signi®cant reduction of mean REE was recorded in the energy-restricted placebo-treated patients (from 8807 AE 498 to 7580 AE 321 kJ/24 h, P`0.05), but not in the patients receiving rhGH (from 8367 AE 580 to 8903 AE 478 kJ/ 24 h, NS). Actually, when corrected for LBM, REE was even increased by GH administration (from 197.9 AE 11.76 to 219.3 AE 9.87 kJ/kg LBM/24 h, P`0.05), whereas it was unchanged in the placebo group (from 201.7 AE 13.85 to 190.0 AE 9.87 kJ/kg LBM/24 h, NS). A tendency of serum markers of bone turnover to increase was observed in the patients treated with rhGH, however with no changes in bone mineral content and density. CONCLUSION: rhGH treatment, though unable to enhance diet-induced weight and fat mass reduction...

show abstract

“…It has been well documented that exogenous GH administration enhances peripheral deiodination of T 4 to T 3 (27)(28)(29)(30). Since monitoring of CH is based on serum fT 4 levels, the decline of its levels during GH treatment will usually lead to an increase in the L-T 4 dose (29,31).…”

Section: Discussionmentioning

confidence: 99%

Clinical and hormonal characteristics of central hypothyroidism at diagnosis and during follow-up in adult patients

et al. 2004

View full text Add to dashboard Cite

Objective: We studied the clinical and hormonal profiles of patients with central hypothyroidism (CH), the adequacy of levothyroxine (L-T4) treatment and the influence of other pituitary hormone replacement therapies. Methods: We reviewed medical records of 108 adult patients with child-onset (CO; n ¼ 26) or adultonset (AO; n ¼ 82) CH. Results: At diagnosis, the most frequently reported symptoms were fatigue and headaches in AO patients, and growth retardation in CO patients. Serum TSH was normal in a majority of CH patients, low in 8% and elevated in 8%. Serum free thyroxine (fT 4 ) was usually reduced, but remained within the low normal range in 28% of the study population (mostly CO patients). Similarly, serum total T 4 (tT 4 ), total triiodothyronine (tT 3 ) and free T 3 (fT 3 ) were found to be within the normal range in significant subsets of patients. Interestingly, the clinical and biochemical characteristics of CH patients with normal f/t T 4 levels were not different from those of the patients with low fT 4 values. The thyroid hormonal profile was not influenced by gender, etiology or by the number of hormone deficiencies. At last evaluation, the mean dose of L-T 4 was 1.6^0.5 mg/kg/day and was negatively correlated to current age (P , 0.001) but positively correlated to the number of hormone deficiencies (P , 0.05). Treatment suppressed TSH in 75% of the patients, induced normal fT 4 in 94%, but normal fT 3 in only 49% of them. Male GH-treated patients and estrogen-treated females needed a higher L-T 4 dose compared with non-treated patients. Conclusions: fT 4 is clearly the best indicator of CH, but remains in the low normal range in a significant subset of patients, especially in those with CO disease. Adequacy of therapy is mostly reflected by the combination of upper normal fT 4 and low normal fT 3 levels. Pituitary hormone replacement therapy may require an adjustment of T 4 treatment, as female patients under estrogen treatment and male patients under GH treatment will need a higher T 4 dose in order to remain in the euthyroid range.European Journal of Endocrinology 150 1-8

show abstract

Growth hormone administration stimulates energy expenditure and extrathyroidal conversion of thyroxine to triiodothyronine in a dose‐dependent manner and suppresses circadian thyrotrophin levels: studies in GH‐deficient adults

Cited by 152 publications

References 32 publications

Median-lower normal levels of serum thyroxine are associated with low triiodothyronine levels and body temperature in patients with central hypothyroidism

Median-lower normal levels of serum thyroxine are associated with low triiodothyronine levels and body temperature in patients with central hypothyroidism

Metabolic effects of biosynthetic growth hormone treatment in severely energy-restricted obese women

Clinical and hormonal characteristics of central hypothyroidism at diagnosis and during follow-up in adult patients

Contact Info

Product

Resources

About