Insulin-like growth factor-I response to a single bolus of growth hormone is increased in obesity.

2.50
Hdl Handle:
http://hdl.handle.net/10541/76574
Title:
Insulin-like growth factor-I response to a single bolus of growth hormone is increased in obesity.
Authors:
Gleeson, Helena K; Lissett, Catherine A; Shalet, Stephen M
Abstract:
Reduced GH levels are found in obesity; despite which IGF-I levels are reported as low normal or normal. Previously peripheral responsiveness to GH has been investigated and reported to be increased in obese men and premenopausal women; however, the use of weight-based GH doses in these studies made data interpretation difficult. GH binding protein (GHBP) measurement constitutes an indirect estimate of GH receptor number. GHBP has been reported to be elevated in obesity; however, results from a recent study implied that this was only in men and premenopausal but not postmenopausal women. Therefore, we pursued this question further by challenging a cohort of healthy normal-weight and obese subjects with a non-weight-based dose of GH and examined the relationship of GHBP with the IGF-I response in the context of their body composition. Ninety-eight (40 male) healthy subjects with a wide range of ages and body mass index (BMI) were studied. Ninety-one (34 male) of these subjects were divided into groups of similar age: men and women with a BMI less than 30 [normal-weight men (NM), BMI 26 (22-29) kg/m(2) (n = 19) and women (NW), BMI 24 (19-29) kg/m(2) (n = 23) and with a BMI > 30 (obese men (OM), 41 (30-72) kg/m(2) (n = 15) and women (OW), 43 (30-68) kg/m(2) (n = 34)]. Fat mass and percentage fat were measured by a bioelectrical impedance analyzer. An IGF-I generation test, which involved a sc injection of 21 IU (7 mg) GH, was performed. At baseline serum samples were assayed for GHBP; serum IGF-I and IGFBP3 levels were measured both at baseline and 24 h after GH administration. There was a higher increment IGF-I in obese men and women, compared with the equivalent normal-weight subjects [NM vs. OM: 245 (33-342) vs. 291 (192-427) ng/ml (P < 0.05); NW vs. OW: 220 (103-435) vs. 315 (144-450) ng/ml (P < 0.0005)]. Increment IGF-I was negatively correlated with baseline IGF-I (F = 12.1) and positively correlated with GHBP (F = 18.2) (R(2) = 0.29). GHBP levels were significantly higher in OM and OW (pre- and postmenopausal) than in the equivalent normal-weight groups [NM vs. OM: 2175 (995-4190) vs. 3030 (1540-5470) pmol/liter (P < 0.05); NW vs. OW: 2131 (1010-5040) vs. 3585 (1540-5740) pmol/liter (P < 0.0005)]. GHBP levels correlated highly with BMI, percentage fat, and fat mass (R > 0.6, P < 0.0001). Baseline IGF-I was not affected by body composition. In conclusion, in obese compared with normal-weight healthy subjects, there is a larger increment IGF-I to a single bolus of GH in men, and irrespective of menopausal status, women. Increment IGF-I is associated positively with GHBP level, which in turn is associated with markers of increasing obesity in men and women. GH responsiveness is increased in obesity.
Affiliation:
Department of Endocrinology, Christie Hospital, Manchester M20 4BX, UK. helena.gleeson@christie-tr.nwest.nhs.uk
Citation:
Insulin-like growth factor-I response to a single bolus of growth hormone is increased in obesity. 2005, 90 (2):1061-7 J. Clin. Endocrinol. Metab.
Journal:
The Journal of Clinical Endocrinology and Metabolism
Issue Date:
Feb-2005
URI:
http://hdl.handle.net/10541/76574
DOI:
10.1210/jc.2004-0501
PubMed ID:
15522943
Type:
Article
Language:
en
ISSN:
0021-972X
Appears in Collections:
All Christie Publications

Full metadata record

DC FieldValue Language
dc.contributor.authorGleeson, Helena K-
dc.contributor.authorLissett, Catherine A-
dc.contributor.authorShalet, Stephen M-
dc.date.accessioned2009-08-06T15:07:58Z-
dc.date.available2009-08-06T15:07:58Z-
dc.date.issued2005-02-
dc.identifier.citationInsulin-like growth factor-I response to a single bolus of growth hormone is increased in obesity. 2005, 90 (2):1061-7 J. Clin. Endocrinol. Metab.en
dc.identifier.issn0021-972X-
dc.identifier.pmid15522943-
dc.identifier.doi10.1210/jc.2004-0501-
dc.identifier.urihttp://hdl.handle.net/10541/76574-
dc.description.abstractReduced GH levels are found in obesity; despite which IGF-I levels are reported as low normal or normal. Previously peripheral responsiveness to GH has been investigated and reported to be increased in obese men and premenopausal women; however, the use of weight-based GH doses in these studies made data interpretation difficult. GH binding protein (GHBP) measurement constitutes an indirect estimate of GH receptor number. GHBP has been reported to be elevated in obesity; however, results from a recent study implied that this was only in men and premenopausal but not postmenopausal women. Therefore, we pursued this question further by challenging a cohort of healthy normal-weight and obese subjects with a non-weight-based dose of GH and examined the relationship of GHBP with the IGF-I response in the context of their body composition. Ninety-eight (40 male) healthy subjects with a wide range of ages and body mass index (BMI) were studied. Ninety-one (34 male) of these subjects were divided into groups of similar age: men and women with a BMI less than 30 [normal-weight men (NM), BMI 26 (22-29) kg/m(2) (n = 19) and women (NW), BMI 24 (19-29) kg/m(2) (n = 23) and with a BMI > 30 (obese men (OM), 41 (30-72) kg/m(2) (n = 15) and women (OW), 43 (30-68) kg/m(2) (n = 34)]. Fat mass and percentage fat were measured by a bioelectrical impedance analyzer. An IGF-I generation test, which involved a sc injection of 21 IU (7 mg) GH, was performed. At baseline serum samples were assayed for GHBP; serum IGF-I and IGFBP3 levels were measured both at baseline and 24 h after GH administration. There was a higher increment IGF-I in obese men and women, compared with the equivalent normal-weight subjects [NM vs. OM: 245 (33-342) vs. 291 (192-427) ng/ml (P < 0.05); NW vs. OW: 220 (103-435) vs. 315 (144-450) ng/ml (P < 0.0005)]. Increment IGF-I was negatively correlated with baseline IGF-I (F = 12.1) and positively correlated with GHBP (F = 18.2) (R(2) = 0.29). GHBP levels were significantly higher in OM and OW (pre- and postmenopausal) than in the equivalent normal-weight groups [NM vs. OM: 2175 (995-4190) vs. 3030 (1540-5470) pmol/liter (P < 0.05); NW vs. OW: 2131 (1010-5040) vs. 3585 (1540-5740) pmol/liter (P < 0.0005)]. GHBP levels correlated highly with BMI, percentage fat, and fat mass (R > 0.6, P < 0.0001). Baseline IGF-I was not affected by body composition. In conclusion, in obese compared with normal-weight healthy subjects, there is a larger increment IGF-I to a single bolus of GH in men, and irrespective of menopausal status, women. Increment IGF-I is associated positively with GHBP level, which in turn is associated with markers of increasing obesity in men and women. GH responsiveness is increased in obesity.en
dc.language.isoenen
dc.subject.meshAdult-
dc.subject.meshAged-
dc.subject.meshAged, 80 and over-
dc.subject.meshBody Mass Index-
dc.subject.meshCarrier Proteins-
dc.subject.meshFemale-
dc.subject.meshHuman Growth Hormone-
dc.subject.meshHumans-
dc.subject.meshInsulin-Like Growth Factor I-
dc.subject.meshMale-
dc.subject.meshMiddle Aged-
dc.subject.meshObesity-
dc.subject.meshPostmenopause-
dc.subject.meshPremenopause-
dc.subject.meshReference Values-
dc.titleInsulin-like growth factor-I response to a single bolus of growth hormone is increased in obesity.en
dc.typeArticleen
dc.contributor.departmentDepartment of Endocrinology, Christie Hospital, Manchester M20 4BX, UK. helena.gleeson@christie-tr.nwest.nhs.uken
dc.identifier.journalThe Journal of Clinical Endocrinology and Metabolismen
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