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Ohara E, Tokuyama H, Kitamoto T, Kitahara A, Hayashi A, Hayashi H, Takemoto M, Yokote K. Laparoscopic Sleeve Gastrectomy Resolves Low GHRP-2-Stimulated Growth Hormone Levels in Obese Patients. Obes Surg 2017. [PMID: 28623445 DOI: 10.1007/s11695-017-2769-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Because growth hormone (GH) secretion is reportedly decreased in obese patients, we examined not only the factors associated with the decreased GH secretion but also GH response to the GH-releasing peptide (GHRP)-2-load test before and after laparoscopic gastrectomy (LSG). The study comprised 28 individuals aged 19-65 years [mean body mass index (BMI), 39.4 ± 9.4 kg/m2]. In the univariate analysis, GH secretion peaks correlated negatively with BMI (r = -0.59, p = 0.001), visceral adipose tissue (r = -0.47, p = 0.005), and subcutaneous adipose tissue (r = -0.40, p = 0.04). In the two obese patients, the response to the GHRP-2-load test markedly improved by weight loss 12 months after LSG. In conclusion, GH secretion was decreased in obese patients and improved by LSG.
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Affiliation(s)
- Emi Ohara
- Department of Clinical Cell Biology and Medicine, Chiba University Graduate School of Medicine, 1-8-1 Inohana, Chuo-ku, Chiba-shi, Chiba, 260-8670, Japan
| | - Hirotake Tokuyama
- Department of Clinical Cell Biology and Medicine, Chiba University Graduate School of Medicine, 1-8-1 Inohana, Chuo-ku, Chiba-shi, Chiba, 260-8670, Japan.,Yu-karigaoka Tokuyama Clinic, Sakura-shi, Chiba, 285-0850, Japan
| | - Takumi Kitamoto
- Department of Clinical Cell Biology and Medicine, Chiba University Graduate School of Medicine, 1-8-1 Inohana, Chuo-ku, Chiba-shi, Chiba, 260-8670, Japan.,Department of Medicine, Division of Diabetes, Metabolism and Endocrinology, Chiba University Hospital, 1-8-1 Inohana, Chuo-ku, Chiba-shi, Chiba, 260-8670, Japan
| | - Aya Kitahara
- Department of Medicine, Division of Diabetes, Metabolism and Endocrinology, Chiba University Hospital, 1-8-1 Inohana, Chuo-ku, Chiba-shi, Chiba, 260-8670, Japan
| | - Aiko Hayashi
- Department of Clinical Cell Biology and Medicine, Chiba University Graduate School of Medicine, 1-8-1 Inohana, Chuo-ku, Chiba-shi, Chiba, 260-8670, Japan.,Department of Medicine, Division of Diabetes, Metabolism and Endocrinology, Chiba University Hospital, 1-8-1 Inohana, Chuo-ku, Chiba-shi, Chiba, 260-8670, Japan
| | - Hideki Hayashi
- Department of Frontier Surgery, Chiba University Graduate School of Medicine, 1-8-1 Inohana, Chuo-ku, Chiba-shi, Chiba, 260-8670, Japan
| | - Minoru Takemoto
- Department of Clinical Cell Biology and Medicine, Chiba University Graduate School of Medicine, 1-8-1 Inohana, Chuo-ku, Chiba-shi, Chiba, 260-8670, Japan. .,School of Medicine, International University of Health and Welfare Department of Diabetes, Metabolism and Endocrinology, 4-3 Kozunomori, Narita-shi, Chiba, 286-8686, Japan.
| | - Koutaro Yokote
- Department of Clinical Cell Biology and Medicine, Chiba University Graduate School of Medicine, 1-8-1 Inohana, Chuo-ku, Chiba-shi, Chiba, 260-8670, Japan.,Department of Medicine, Division of Diabetes, Metabolism and Endocrinology, Chiba University Hospital, 1-8-1 Inohana, Chuo-ku, Chiba-shi, Chiba, 260-8670, Japan
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Luque RM, Gahete MD, Cordoba-Chacon J, Childs GV, Kineman RD. Does the pituitary somatotrope play a primary role in regulating GH output in metabolic extremes? Ann N Y Acad Sci 2011; 1220:82-92. [PMID: 21388406 DOI: 10.1111/j.1749-6632.2010.05913.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Circulating growth hormone (GH) levels rise in response to nutrient deprivation and fall in states of nutrient excess. Because GH regulates carbohydrate, lipid, and protein metabolism, defining the mechanisms by which changes in metabolism alter GH secretion will aid in our understanding of the cause, progression, and treatment of metabolic diseases. This review will summarize what is currently known regarding the impact of systemic metabolic signals on GH-axis function. In addition, ongoing studies using the Cre/loxP system to generate mouse models with selective somatotrope resistance to metabolic signals will be discussed, where these models will serve to enhance our understanding of the specific role the somatotrope plays in sensing the metabolic environment and adjusting GH output in metabolic extremes.
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Affiliation(s)
- Raul M Luque
- Department of Cell Biology, Physiology and Immunology, University of Cordoba, Instituto Maimónides de Investigación Biomédica de Córdoba, CIBER Fisiopatología de la Obesidad y Nutrición, Córdoba, Spain
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3
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Ghigo E, Aimaretti G, Corneli G. Diagnosis of adult GH deficiency. Growth Horm IGF Res 2008; 18:1-16. [PMID: 17766155 DOI: 10.1016/j.ghir.2007.07.004] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2007] [Accepted: 07/09/2007] [Indexed: 10/22/2022]
Abstract
The current guidelines for the diagnosis of adult GHD are mainly based on the statements from the GH Research Society Consensus from Port Stevens in 1997. It is stated that diagnosis of adult GHD must be shown biochemically by provocative tests within the appropriate clinical context. The insulin tolerance test (ITT) was indicated as that of choice and severe GHD defined by a GH peak lower than 3 microg/L. The need to rely on provocative tests is based on evidence that that the measurement of IGF-I as well as of IGFBP-3 levels does not distinguish between normal and GHD subjects. Hypoglycemia may be contraindicated; thus, alternative provocative tests were considered, provided they are used with appropriate cut-off limits. Among classical provocative tests, arginine and glucagon alone were indicated as alternative tests, although less discriminatory than ITT. Testing with the combined administration of GHRH plus arginine was recommended as an alternative to ITT, mostly taking into account its marked specificity. Based on data in the literature in the last decade, the GRS Consensus Statements should be appropriately amended. Regarding the appropriate clinical context for the suspicion of adult GHD, one should evaluate patients with hypothalamic or pituitary disease or a history of cranial irradiation, as well as those with childhood-onset GHD are at obvious risk as adults for severe GHD. Brain injuries (trauma, subarachnoid hemorrage, tumours of the central nervous system) very often cause acquired hypopituitarism, including severe GHD. Given the epidemiology of brain injuries, the important role of the endocrinologist in providing major clinical benefit to brain injured patients who are still undiagnosed should be underscored. From the biochemical point of view, although normal IGF-I levels do not rule out severe GHD, very low IGF-I levels in patients highly suspected for GHD (i.e. patients with childhood-onset, severe GHD or with multiple hypopituitarism acquired in adulthood) can be considered as definitive evidence for severe GHD; thus, these patients would skip provocative tests. Patients suspected for adult GHD with normal IGF-I levels must be investigated by provocative tests. ITT remains a test of reference but it should be recognized that other tests are as reliable as ITT. Glucagon as classical test and, particularly, new maximal tests such as GHRH in combination with arginine or GH secretagogues (GHS) (i.e. GHRP-6) have well defined cut-off limits, are reproducible, able to distinguish between normal and GHD subjects. Overweight and obesity have confounding effect on the interpretation of the GH response to provocative tests. In adults cut-off levels of GH response below which severe GHD is demonstrated must be appropriate to lean, overweight and obese subjects to avoid false positive diagnosis in obese adults and false negative diagnosis in lean GHD patients. Finally, normative values of GH response to provocative tests may depend on age, particularly in the transitional age; the normative cut-off levels of GH response to ITT in this phase of life are now available.
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Affiliation(s)
- E Ghigo
- Division of Endocrinology and Metabolism, Department of Internal Medicine, University of Turin, Turin, Italy.
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Gasco V, Corneli G, Rovere S, Croce C, Beccuti G, Mainolfi A, Grottoli S, Aimaretti G, Ghigo E. Diagnosis of adult GH deficiency. Pituitary 2008; 11:121-8. [PMID: 18404387 DOI: 10.1007/s11102-008-0110-x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Based on previous consensus statements, it has been widely accepted that the diagnosis of adult growth hormone deficiency (GHD) must be shown biochemically by provocative tests of GH secretion; in fact, the measurement of IGF-I as well as of other markers was considered unable to distinguish between normal and GHD subjects. The Insulin Tolerance Test (ITT) was indicated as that of choice and severe GHD defined by a GH peak lower than 3 microg/l. It is now recognized that, although normal IGF-I levels do not rule out severe GHD, very low IGF-I levels in patients highly suspected for GHD (i.e. patients with childhood-onset severe GHD or with multiple hypopituitarism acquired in adulthood) can be considered as definite evidence for severe GHD. However, patients suspected for adult GHD with normal IGF-I levels must be investigated by provocative tests. ITT remains a test of reference but it should be recognized that other tests are as reliable as ITT. Glucagon as classical test and, particularly, new maximal tests such as GHRH in combination with arginine or GH secretagogues (GHS) (i.e. GHRP-6) have well defined cut-off limits, are reproducible, able to distinguish between normal and GHD subjects. Overweight and obesity have confounding effect on the interpretation of the GH response to provocative tests. In adults cut-off levels of GH response below which severe GHD is demonstrated must be appropriate to lean, overweight and obese subjects to avoid false positive diagnosis in obese adults and false negative diagnosis in lean GHD patients.
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Affiliation(s)
- V Gasco
- Department of Internal Medicine, Division of Endocrinology and Metabolism, Molinette Hospital, University of Turin, Turin, Italy
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Veldhuis JD, Cosma M, Erickson D, Paulo R, Mielke K, Farhy LS, Bowers CY. Tripartite control of growth hormone secretion in women during controlled estradiol repletion. J Clin Endocrinol Metab 2007; 92:2336-45. [PMID: 17405836 DOI: 10.1210/jc.2007-0043] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Studies of how aging attenuates GH secretion are confounded by differences in sex-steroid milieus, abdominal visceral fat mass (AVF), and IGF-I concentrations and limited in interpretability by the use of pharmacological doses of secretagogues. HYPOTHESIS In a controlled estrogenic milieu, near-physiological secretagogue drive will unmask distinct influences of age, AVF, and IGF-I on GH secretion. LOCATION The study was conducted at an academic medical center. SUBJECTS Subjects included 10 healthy pre- (PRE) and 10 postmenopausal (POST) women. PROCEDURE In a defined estradiol (E(2)) milieu, we compared GH secretion after submaximal stimulation with GH-releasing peptide (GHRP)-2 (ghrelin analog), GHRH, and l-arginine (an inhibitor of somatostatin outflow). ANALYSIS We related GH responses to age stratum (dichotomous variable) and AVF and IGF-I concentrations (continuous variables). RESULTS In the face of comparable concentrations of E(2), testosterone, and SHBG: 1) age (P < 0.001) and secretagogue type (P < 0.001) independently determined GH secretion; 2) GH responses in POST subjects were only 26-33% of those in PRE (P < or = 0.002) across all secretagogues; 3) POST women lost the PRE order of secretagogue potency (GHRP-2 > GHRH = l-arginine); and 4) in the combined cohorts, higher AVF predicted reduced l-arginine-stimulated GH secretion (R(2) = 0.46, P = 0.0013), whereas higher IGF-I concentrations forecast increased GHRP-2 and GHRH drive (R(2) > or = 0.52, P < or = 0.013). CONCLUSION A paradigm of near-physiological secretagogue drive in an E(2)-clamped milieu unmasks tripartite deficits in peptide-signaling pathways in healthy POST, compared with PRE, women. Post hoc analyses indicate that both greater visceral adiposity and lower IGF-I concentrations mark this triple regulatory defect.
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Affiliation(s)
- Johannes D Veldhuis
- Endocrine Research Unit 9, General Clinical Research Center, Mayo Medical and Graduate Schools of Medicine, Mayo Clinic, Rochester, MN 55905, USA.
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Alonso G, Sanchez-Hormigo A, Loudes C, El Yandouzi T, Carmignac D, Faivre-Bauman A, Recolin B, Epelbaum J, Robinson ICAF, Mollard P, Méry PF. Selective alteration at the growth-hormone- releasing-hormone nerve terminals during aging in GHRH-green fluorescent protein mice. Aging Cell 2007; 6:197-207. [PMID: 17328688 DOI: 10.1111/j.1474-9726.2007.00276.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Growth hormone (GH) secretion decreases spontaneously during lifespan, and the resulting GH deficiency participates in aging-related morbidity. This deficiency appears to involve a defect in the activity of hypothalamic GH-releasing hormone (GHRH) neurons. Here, we investigated this hypothesis, as well as the underlying mechanisms, in identified GHRH neurons from adult ( approximately 13 weeks old) and aged ( approximately 100 weeks old) transgenic GHRH-green fluorescent protein mice, using morphological, biochemical and electrophysiological methods. Surprisingly, the spontaneous action potential frequency was similar in adult and aged GHRH neurons studied in brain slices. This was explained by a lack of change in the intrinsic excitability, and simultaneous increases in both stimulatory glutamatergic- and inhibitory GABAergic-synaptic currents of aged GHRH neurons. Aging did not decrease GHRH and enhanced green fluorescent protein contents, GHRH neuronal number or GHRH-fibre distribution, but we found a striking enlargement of GHRH-positive axons, suggesting neuropeptide accumulation. Unlike in adults, autophagic vacuoles were evident in aged GHRH-axonal profiles using electron microscopy. Thus, GHRH neurons are involved in aging of the GH axis. Aging had a subtle effect at the nerve terminal level in GHRH neurons, contrasting with the view that neuronal aging is accompanied by more widespread damage.
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Affiliation(s)
- Gérard Alonso
- Département d'Endocrinologie, Institut de Génomique Fonctionnelle, INSERM U661, CNRS UMR 5203, Université Montpellier 1 et 2, Montpellier, France
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Corneli G, Gasco V, Prodam F, Grottoli S, Aimaretti G, Ghigo E. Growth hormone levels in the diagnosis of growth hormone deficiency in adulthood. Pituitary 2007; 10:141-9. [PMID: 17429591 DOI: 10.1007/s11102-007-0031-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Current guidelines for the diagnosis of adult growth hormone deficiency (GHD) state that the diagnosis must be proven biochemically by provocative testing that is done within the appropriate clinical context. The need for reliance on provocative testing is based on evidence that the evaluation of spontaneous growth hormone (GH) secretion over 24 h and the measurement of IGF-I and IGFBP-3 levels do not distinguish between normal and GHD subjects. Regarding IGF-I, it has been demonstrated that very low levels in patients highly suspected for GHD (i.e., patients with childhood-onset, severe GHD, or with multiple hypopituitarism acquired in adulthood) may be considered definitive evidence for severe GHD obviating the need for provocative tests. However, normal IGF-I levels do not rule out severe GHD and therefore adults suspected for GHD and with normal IGF-I levels must undergo a provocative test of GH secretion. The insulin tolerance test (ITT) is the test of choice, with severe GHD being defined by a GH peak less than 3 microg/l, the cut-off that distinguishes normal from GHD adults. The ITT is contraindicated in the presence of ischemic heart disease, seizure disorders, and in the elderly. Other tests are as reliable as the ITT, provided they are used with appropriate cut-off limits. Glucagon stimulation, a classical test, and especially new maximal tests such as GHRH in combination with arginine or GHS (i.e., GHRP-6) have well-defined cut-off limits, are reproducible, are independent of age and gender, and are able to distinguish between normal and GHD subjects. The confounding effect of overweight or obesity on the interpretation of the GH response to provocative tests needs to be considered as the somatotropic response to all stimuli is negatively correlated with body mass index. Appropriate cut-offs for lean, overweight, and obese subjects must be used in order to avoid false-positive diagnoses of severe GHD in obese adults.
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Affiliation(s)
- Ginevra Corneli
- Endocrinology, Department of Clinical and Experimental Medicine, Amedeo Avogadro University, Via Solaroli 17, 28100 Novara, Italy
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Kelestimur F, Popovic V, Leal A, Van Dam PS, Torres E, Perez Mendez LF, Greenman Y, Koppeschaar HPF, Dieguez C, Casanueva FF. Effect of obesity and morbid obesity on the growth hormone (GH) secretion elicited by the combined GHRH + GHRP-6 test. Clin Endocrinol (Oxf) 2006; 64:667-71. [PMID: 16712669 DOI: 10.1111/j.1365-2265.2006.02525.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE Obesity is characterized by low basal levels of growth hormone (GH) and impeded GH release. However, the main problem arises in the diagnosis of GH deficiency in adults, as all accepted cut-offs in the diagnostic tests of GH reserve are no longer valid in obese subjects. In this work, the role of obesity in the GH response elicited by the GHRH + GHRP-6 test was assessed in a large population of obese and nonobese subjects. PATIENTS GHRH + GHRP-6-induced GH peaks were evaluated in 542 subjects. One hundred and five were healthy obese, 50 were morbid obese, and 261 were nonobese (both normal weight and overweight). One hundred and seventy-six GH-deficient patients (obese and nonobese) were also studied. RESULTS A regression analysis of the 366 subjects with normal pituitary function indicated that adiposity had a negative effect on the elicited GH peak (r = -0.503, P < 0.0001). A receiver operating characteristic (ROC) curve analysis showed that in subjects with a BMI < or =35, the currently accepted cut-offs of the GHRH + GHRP-6 test (GH peaks > or =20 microg/l: normal secretion; GH peaks < or =10 microg/l: GH deficiency), were fully operative. However, in subjects with a BMI > 35, normality was indicated by GH peaks > or =15 microg/l and GH deficiency by peaks < or =5 microg/l (1 microg/l = 2.6 mU/l). CONCLUSIONS This study confirms: (a) that the combined provocative test is adequate to separate normal and GH-deficient subjects; (b) the negative effect of obesity on GH secretion; (c) that obesity accounts for 25% of the reduction of GH release; and (d) that present cut-off values are applicable to normal weight, overweight and grade I obesity subjects, whereas in obese subjects with a BMI exceeding 35, all the normative limits of the GHRH-GHRP +6 test must be reduced by 5 microg/l.
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Luque RM, Kineman RD. Impact of obesity on the growth hormone axis: evidence for a direct inhibitory effect of hyperinsulinemia on pituitary function. Endocrinology 2006; 147:2754-63. [PMID: 16513828 DOI: 10.1210/en.2005-1549] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
There is a negative relationship between obesity and GH. However, it is not known how metabolic changes, associated with obesity, lead to a reduction in GH output. This study examined the GH axis of two mouse models of obesity, the leptin-deficient (ob/ob) mouse and the diet-induced obese (DIO; high-fat fed) mouse. Both models displayed hyperglycemia and hyperinsulinemia with reduced expression of GH as well as reduced expression of pituitary receptors important for GH synthesis and release [GHRH receptor (DIO only) and the ghrelin receptor (ob/ob and DIO)]. These pituitary changes were not accompanied by changes in hypothalamic expression of GHRH or somatostatin; suggesting that alterations in pituitary function may be precipitated in part by direct effects of systemic signals. Of the metabolic and hormonal parameters examined (insulin, glucose, corticosterone, free fatty acids, ghrelin, and IGF-I), only insulin/glucose showed a significant, and negative, correlation with pituitary expression. Pituitaries of DIO mice remained responsive to the acute in vivo actions of insulin, as assessed by phosphorylation of Akt, despite systemic (skeletal muscle and fat) insulin resistance. In addition, treating primary pituitary cell cultures from lean mice with insulin reduced GH release as well as GH, GHRH receptor, and ghrelin receptor mRNA levels compared with vehicle-treated controls, where the magnitude of suppression of pituitary mRNA levels was similar to that observed in the DIO mouse. These results coupled with the fact that the pituitary expresses the insulin receptor at levels comparable to tissues classically considered insulin sensitive, indicates high circulating insulin levels can directly contribute to the suppression of GH synthesis and release in the obese state.
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Affiliation(s)
- Raul M Luque
- Section of Endocrinology and Metabolism, Department of Medicine, University of Illinois at Chicago, Illinois, USA
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Abstract
The diagnosis of GH deficiency (GHD) in adults is established by laboratory testing in patients with an appropriate clinical history of hypothalamic pituitary disease. As the measurement of IGF-I and IGFBP-3 levels as well as the spontaneous GH secretion are not considered reliable parameters, the diagnosis of GHD in adults may be established by GH provocative tests, provided that a reproducible test with clear normative limits is available. The insulin tolerance test (ITT) is a reliable diagnostic test in adults, but is contraindicated in several clinical conditions which are often observed in adult patients with suspected GHD. The other classic GH provocative tests, except the glucagon test, have a poor diagnostic utility and should be abandoned. GHRH combined with arginine or GH secretagogues represent a potent, safe, reproducible and reliable test which should be preferable to the ITT as a first-choice diagnostic test for GHD.
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Affiliation(s)
- F Camanni
- Division of Endocrinology and Metabolic Diseases, Department of Internal Medicine, University of Turin, Italy.
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Edén Engström B, Burman P, Holdstock C, Ohrvall M, Sundbom M, Karlsson FA. Effects of gastric bypass on the GH/IGF-I axis in severe obesity--and a comparison with GH deficiency. Eur J Endocrinol 2006; 154:53-9. [PMID: 16381991 DOI: 10.1530/eje.1.02069] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
OBJECTIVE Overfeeding suppresses GH secretion and makes evaluation of a suspected GH deficiency (GHD) difficult. In normal weight subjects, gender is known to influence GH concentrations, which is most apparent in the ambulatory, morning-fasted state. In this study, we examined the GH/IGF-I axis in obese men and women and the effect of surgically induced weight loss. DESIGN Sixty-three subjects (body mass index (BMI) 45 +/- 6 kg/m2; 54 women, 9 men) were studied prior to, and 6 and 12 months following Roux-en-Y gastric bypass (RYGBP) surgery. Fifty-four patients with classic GHD (BMI 27 +/- 6 kg/m2; 35 men, 19 women) were included for comparison. METHODS Hormones were analysed in fasting morning serum samples. RESULTS RYGBP resulted in a decreased BMI to 35 +/- kg/m2 at 6 months and 32 +/- 6 kg/m2 at 12 months. GH and IGF-I increased at 6 months in the women and at 12 months in both sexes by > or = 300 and 11% respectively. Prior to RYGBP, GH concentrations were low in the obese men and similar to those of GHD men (mean 0.09 mU/l). Obese women had tenfold higher values than obese men and sevenfold higher than GHD women. IGF-I levels were in the low reference range in the obese and below -2 S.D. for age in 13%. CONCLUSIONS Surgically induced weight loss partially restores GH secretion. Despite a marked suppression of GH values, a gender influence is maintained in severe obesity. In obese women, single morning GH and IGF-I values seem sufficient to exclude a suspicion of classic GHD.
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Affiliation(s)
- Britt Edén Engström
- Department of Medical Sciences, Internal Medicine, Uppsala University Hospital, Sweden.
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