Circulating growth hormone binding proteins

Baumann, Gerhard; Shaw, Melissa A.; Amburn, Klaus

doi:10.1007/bf03344965

Cited by 57 publications

(26 citation statements)

References 129 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…However, high-affinity GHBP levels, which likely reflect the peripheral GH receptor status (19), have been found unchanged in CS (14), but increased in OB by some (19), but not by others (10) including ourselves in the present study. As GHBP levels are reported to be positively associated with BMI and fat mass (29), may be it mainly reflects to a major extent the adipose tissue sensitivity to GH.…”

Section: Discussioncontrasting

confidence: 60%

“…It has been hypothesized that hyperinsulinism and/or hypercortisolism could lead to peripheral hepatic' GH hypersensitivity allowing for maintained IGF-I synthesis and release in spite of clear-cut reduction of GH secretion in both OB and CS. Circulating GH-binding protein (GHBP) levels, which likely reflect the GH receptor status (19), have been reported increased in OB by some authors (19) and normal in hypercortisolism (14).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Effects of short-term administration of low-dose rhGH on IGF-I levels in obesity and Cushing's syndrome: indirect evaluation of sensitivity to GH

Maccario

Tassone²,

Gauna³

et al. 2001

European Journal of Endocrinology

View full text Add to dashboard Cite

Objective: To verify the hypothesis of an increased sensitivity to GH in obesity (OB) and Cushing's syndrome (CS). Design: We studied the effects of short-term administration of low-dose rhGH on circulating IGF-I levels in patients with simple OB or CS and in normal subjects (NS 2 ) underwent s.c. administration of 5 mg/kg per day rhGH at 2200 h for four days. Serum IGF-I, IGF-binding protein-3 (IGFBP-3), GHbinding protein (GHBP), insulin and glucose levels were determined at baseline and 12 h after the first and the last rhGH administration. Results: Basal IGF-I levels in NS 239X3^22X9 mgal were similar to those in OB 181X5^13X7 mgal and CS 229X0^29X1 mgalX Basal IGFBP-3, GHBP and glucose levels in NS, OB and CS were similar while insulin levels in NS were lower P , 0X01 than those in OB and CS. In NS, the low rhGH dose induced a sustained rise of IGF-I levels (279X0^19X5 mgalY P , 0X001Y a non-significant IGFBP-3 increase and no change in GHBP, insulin and glucose levels. In OB and CS, the IGF-I response to rhGH showed progressive increase (246X2^17X2 and 311X0^30X4 mgal respectively, P , 0X01 vs baseline). Adjusting by ANCOVA for basal values, rhGH-induced IGF-I levels in CS (299.4 mg/l) were higher than in OB (279.1 mg/l, P , 0X01), which, in turn, were higher P , 0X05 than in NS (257.7 mg/l). In OB, but not in CS, IGFBP-3 and insulin levels showed slight but significant P , 0X05 increases during rhGH treatment, which did not modify glucose levels in any group; thus, in the OB patient group a significant fall in glucose/insulin ratio was observed. Conclusions: Short-term treatment with low-dose rhGH has enhanced stimulatory effect on IGF-I levels in OB and, particularly, in hypercortisolemic patients. These findings support the hypothesis that hyperinsulinism and hypercortisolism enhance the sensitivity to GH in humans.

show abstract

Section: Discussioncontrasting

confidence: 60%

Section: Introductionmentioning

confidence: 99%

Effects of short-term administration of low-dose rhGH on IGF-I levels in obesity and Cushing's syndrome: indirect evaluation of sensitivity to GH

Maccario

Tassone²,

Gauna³

et al. 2001

European Journal of Endocrinology

View full text Add to dashboard Cite

show abstract

“…Numerous findings support the idea that circulating GHBP levels reflect GH-R status (Baumann et al 1994a). However, the regulation of GHBP and/or GH-R is not fully elucidated, and some controversial findings were reported in former animal studies (Turyn & Dellacha 1978, Amit et al 1992.…”

Section: Discussionmentioning

confidence: 82%

“…Since the levels of GHBP are closely related to GH-R levels (Amit et al 1992, Cramer et al 1992b, Baumann et al 1994a, Ilkbahar et al 1995, we have studied GHBP to obtain information on the competitive inhibition of GH binding by G119K-bGH in vivo. This was accomplished by estimating the concentration of free, unbound GHBP in normal mouse serum and in the presence of different concentrations of the antagonist.…”

Section: Introductionmentioning

confidence: 99%

Growth hormone (GH) receptors, binding proteins and IGF-I concentrations in the serum of transgenic mice expressing bovine GH agonist or antagonist

Sotelo¹,

Bartke²,

Kopchick³

et al. 1998

Journal of Endocrinology

View full text Add to dashboard Cite

We have examined the regulation of hepatic growth hormone receptors (GH-R) and serum GH binding proteins (GHBP) in transgenic mice expressing an antagonist of bovine growth hormone (bGH), G119K-bGH, and consequently exhibiting a growth suppressed dwarf phenotype. Specific GHBP could be measured in transgenic dwarf mouse serum only by immunological methods (RIA), because these mice have a very high concentration of mutated bGH in circulation (>1 µg/ml) and, therefore, almost all GHBP is bound to G119K-bGH and cannot be quantitated in binding assays. The concentrations of GHBP were 0·6 0·4 nM and 1·7 0·4 nM for normal and dwarf mice respectively. The concentrations of free GHBP in normal mice and in transgenic mice expressing wild-type GH can be calculated using chromatographic techniques as the dissociation constant (K d ) and the ratio of bound 125

show abstract

“…It has been clearly shown that the GH-receptor (GH-R) status is regulated by GH itself (24). In GHD, many authors reporting contrasting results (19, 24±29) have studied GH binding protein (GHBP) levels as a marker of GH-R status.…”

Section: Discussionmentioning

confidence: 99%

Enhancement of the peripheral sensitivity to growth hormone in adults with GH deficiency

Aimaretti

Fanciulli²,

Bellone³

et al. 2001

European Journal of Endocrinology

View full text Add to dashboard Cite

Objective: Adults with severe GH de®ciency (GHD) need recombinant human growth hormone (rhGH) replacement to restore body composition, structure functions and metabolic abnormalities. The optimal rhGH dose for replacement has been progressively reduced to avoid side effects. The aim of the present study was to de®ne the minimal rhGH dose able to increase both IGF-I and IGF binding protein (BP)-3 levels in GHD and to verify the possible change in GH sensitivity. Design and patients: To this goal, we studied the effect of 4-day treatment with 3 rhGH doses (1.25, 2.5 and 5.0 mg/kg/day) on IGF-I and IGFBP-3 levels in 25 panhypopituitary adults with severe GHD (12 males and 13 females, age: 44X5^3X0 years, body mass index (BMI): 27X0^0X9 kgam 2 ) and 21 normal young adult volunteers (NV, 12 males and 9 females, age: 30X5^2X0 years, BMI: 20X8^0X5 kgam 2 ). Results: Basal IGF-I and IGFBP-3 levels in GHD were lower P , 0X001 than in NV. In NV the 1.25 mg/kg dose of rhGH did not modify IGF-I levels. The dose of 2.5 mg/kg rhGH signi®cantly increased IGF-I levels in men P , 0X001 but not in women, while the 5.0 mg/kg dose increased IGF-I levels in both sexes P , 0X001X IGFBP-3 levels were not modi®ed by any of the administered rhGH doses. In GHD patients, all rhGH doses increased IGF-I levels 12 h after both the ®rst P , 0X01 and the fourth rhGH dose P , 0X001X At the end of treatment percentage increases in IGF-I were higher P , 0X001 in GHD patients than in NV. In contrast with NV, in GHD patients the IGF-I response to short-term stimulation with rhGH was independent of gender. Moreover, GHD patients showed increases in IGFBP-3 after the fourth administration of both 2.5 and 5.0 mg/kg rhGH. Conclusion:The results of the present study demonstrate that the minimal rhGH dose able to increase IGF-I and IGFBP-3 levels in GHD patients is lower than in normal subjects, at least after a very short treatment. This evidence suggests an enhanced peripheral GH sensitivity in GH deprivation.

show abstract

Circulating growth hormone binding proteins

Cited by 57 publications

References 129 publications

Effects of short-term administration of low-dose rhGH on IGF-I levels in obesity and Cushing's syndrome: indirect evaluation of sensitivity to GH

Effects of short-term administration of low-dose rhGH on IGF-I levels in obesity and Cushing's syndrome: indirect evaluation of sensitivity to GH

Growth hormone (GH) receptors, binding proteins and IGF-I concentrations in the serum of transgenic mice expressing bovine GH agonist or antagonist

Enhancement of the peripheral sensitivity to growth hormone in adults with GH deficiency

Contact Info

Product

Resources

About