Abstract:
OBJECTIVE:In order to better understand how the IGF-I axis is affected by exogenous IGF-I, this study compared the effects of a constant s.c. infusion of IGF-I with that of twice-daily injections of IGF-I in young adult female rhesus monkeys. Clinical studies suggest that circulating concentrations of insulin-like growth factor binding protein-3 (IGFBP-3) are decreased or unaffected by IGF-I administration, whereas acute increases in IGF-I may increase serum IGFBP-1. However, studies in monkeys indicate that acute or continuous infusion of IGF-I effectively increases serum IGFBP-3. DESIGN AND METHODS:Female monkeys were studied for 5 days with no IGF-I supplementation (baseline) and for 5 days of IGF-I treatment by either constant infusion (120 microg/kg per day s.c., n = 5) or twice-daily injections of IGF-I (60 microg/kg per injection s.c., n = 5). Serum samples were collected daily at 0800 h and at 0800, 0900, 1100, 1500, and 2000 h on days 1 and 4 for each condition. Samples were assayed for IGF-I, IGFBPs-1 and -3, insulin, and glucose. RESULTS:Serum IGF-I was consistently increased above baseline within 24 h of the initiation of constant infusion, but was delayed until the second day of treatment in the injection group. Serum IGFBP-3 followed the pattern of IGF-I, with concentrations increased by day 1 during constant infusion and by day 2 during intermittent injections. Although both treatments effectively increased serum IGFBP-3, the increase was greater during constant infusion (31% above baseline) compared with injection (17%). Immunoblotting revealed that the constant infusion of IGF-I resulted in quantitatively more lower-molecular-mass fragments of IGFBP-3 than were observed during baseline or intermittent injections. Size-exclusion chromatography and ultrafiltration indicated that most IGFBP-3 was found in the ternary complex, with a greater percentage found in the ternary complex during baseline (90%) than during constant infusion (86%) or intermittent injections of IGF-I (87%). In contrast, serum concentrations of IGFBP-1 were increased on day 1 of both treatments, but declined towards baseline values as treatment progressed. Serum concentrations of insulin and glucose were unaffected by either mode of IGF-I treatment. Serum concentrations of IGF-I and IGFBP-3 were increased within 3h of the injection, before declining towards the pre-injection level. In contrast, the daily pattern of serum hormone concentrations was similar between the baseline condition and during constant infusion of IGF-I. Although higher during the treatment phase, serum IGF-I and IGFBP-3 concentrations decreased significantly from 0800 h until the afternoon meal, reaching a nadir in the evening before increasing again the next morning. Serum insulin decreased also after the morning meal and increased significantly immediately after the afternoon meal. Although serum IGFBP-1 also decreased initially after the morning meal, concentrations reached a peak before the afternoon meal as serum insulin reached its nadir. CONCLUSION:The results of the present analysis indicate that the constant infusion of IGF-I more effectively sustains serum concentrations of IGF-I and IGFBP-3 than do twice-daily injections. Although the percentage of IGF-I and IGFBP-3 in the ternary complex was similar during both treatments, the constant infusion regimen produced lower-molecular-mass fragments of IGFBP-3. In addition, serum IGF-I and IGFBP-3 appeared to be regulated diurnally, even during IGF-I infusion, whereas IGFBP-1 and insulin were affected by the timing of food intake. Taken together, these data suggest that, in the monkey, IGFBP-3 is regulated by factors in addition to GH, and that IGF-I can affect its own bioavailability by increasing circulating concentrations of IGFBP-3.
journal_name
Eur J Endocrinoljournal_title
European journal of endocrinologyauthors
Wilson ME,Lackey SLdoi
10.1530/eje.0.1410303subject
Has Abstractpub_date
1999-09-01 00:00:00pages
303-12issue
3eissn
0804-4643issn
1479-683Xpii
1410303journal_volume
141pub_type
杂志文章abstract:Objective:Retrospective studies suggest that women have more active brown adipose tissue (BAT) than men, but little is known of the effect of fluctuating sex steroids across the menstrual cycle on thermogenesis in women. Design:To characterise the effects of sex and sex steroids on BAT activity we recruited healthy we...
journal_title:European journal of endocrinology
pub_type: 杂志文章
doi:10.1530/EJE-20-0184
更新日期:2020-09-01 00:00:00
abstract:INTRODUCTION:The fetus is most vulnerable to severe iodine deficiency and hypothyroidism during pregnancy. The effects of mild iodine deficiency and subclinical hypothyroidism are poorly known. The present study assesses the association between thyroid hormones (TH)s and urinary iodine concentration (UIC) in healthy pr...
journal_title:European journal of endocrinology
pub_type: 杂志文章
doi:10.1530/EJE-08-0716
更新日期:2009-03-01 00:00:00
abstract:OBJECTIVE:The orexigenic and adipogenic peptide hormone ghrelin is predominantly produced and secreted by the stomach and seems to transduce changes in food intake to specific neuronal circuits in the brain. The activity of ghrelin also includes stimulatory effects on the corticotropic system. However, little is known ...
journal_title:European journal of endocrinology
pub_type: 杂志文章
doi:10.1530/eje.0.1510113
更新日期:2004-07-01 00:00:00
abstract:BACKGROUND:Individuals carrying a heterozygous inactivating PAX8 mutation are affected by congenital hypothyroidism (CH), although heterozygous Pax8 knockout mice are not. It has remained unclear whether CH in PAX8 mutation carriers is caused by haploinsufficiency or a dominant negative mechanism. OBJECTIVE:To report ...
journal_title:European journal of endocrinology
pub_type: 杂志文章
doi:10.1530/EJE-12-0410
更新日期:2012-11-01 00:00:00
abstract:OBJECTIVE:Glucocorticoid excess leads to insulin resistance. This study explores the effects of glucocorticoids on the glucose transport system and insulin signalling in rat adipocytes. The interaction between glucocorticoids and high levels of insulin and glucose is also addressed. DESIGN AND METHODS:Isolated rat adi...
journal_title:European journal of endocrinology
pub_type: 杂志文章
doi:10.1530/eje.0.1460419
更新日期:2002-03-01 00:00:00
abstract:Objective:Several clinical studies have reported that renal impairments are sometimes observed in patients with primary aldosteronism (PA). We analyzed the prevalence of renal impairments in PA patients and identified parameters that increase the risk for them. Design:This is a retrospective cross-sectional study. We ...
journal_title:European journal of endocrinology
pub_type: 杂志文章
doi:10.1530/EJE-19-0047
更新日期:2019-09-01 00:00:00
abstract::The human growth hormone variant (GH-V) gene is expressed during pregnancy in the syncytiotrophoblast and, as shown recently, in the normal human testis. In addition to the classical transcript encoding for the 22 K major form, intron D-retaining processed mRNAs (GH-V2) have also been described in both tissues. In the...
journal_title:European journal of endocrinology
pub_type: 杂志文章
doi:10.1530/eje.0.1390424
更新日期:1998-10-01 00:00:00
abstract:OBJECTIVES:The aim of the present study was to determine vascular endothelial growth factor (VEGF), prostaglandin E(2) (PGE(2)) and active renin levels in patients with hormonally active adrenal tumours. DESIGN:The study was comprised of 16 patients with primary aldosteronism, 13 patients with active Cushing's syndrom...
journal_title:European journal of endocrinology
pub_type: 杂志文章
doi:10.1530/eje.0.1500345
更新日期:2004-03-01 00:00:00
abstract::Objective Chronic hypoparathyroidism and its treatment may lead to symptoms and complications affecting quality of life. We determined complications in chronic hypoparathyroid patients. Design Retrospective cross-sectional study of patients with chronic hypoparathyroidism treated with active vitamin D supplements in a...
journal_title:European journal of endocrinology
pub_type: 杂志文章
doi:10.1530/EJE-18-0580
更新日期:2019-01-01 00:00:00
abstract::Nelson's syndrome is a potentially life-threatening condition that does not infrequently develop following total bilateral adrenalectomy (TBA) for the treatment of Cushing's disease. In this review article, we discuss some controversial aspects of Nelson's syndrome including diagnosis, predictive factors, aetiology, p...
journal_title:European journal of endocrinology
pub_type: 杂志文章,评审
doi:10.1530/EJE-10-0466
更新日期:2010-10-01 00:00:00
abstract:OBJECTIVE:While anti-pituitary antibodies (APAs) were detected in some patients with Sheehan's syndrome (SS) suggesting an autoimmune pituitary involvement in the development of their hypopituitarism, hypothalamic cell anti-hypothalamus antibodies (AHAs) have not been investigated so far. DESIGN:The aim of this study ...
journal_title:European journal of endocrinology
pub_type: 杂志文章
doi:10.1530/EJE-07-0647
更新日期:2008-02-01 00:00:00
abstract::Low levels of insulin-like growth factor I (IGF-I) in critical illness are observed despite increased or normal levels of growth hormone (GH). The mechanisms for this apparent GH resistance have not been elucidated. As many of the acute inflammatory responses in critical illness are mediated by the proinflammatory cyt...
journal_title:European journal of endocrinology
pub_type: 杂志文章
doi:10.1530/eje.0.1350729
更新日期:1996-12-01 00:00:00
abstract:OBJECTIVE:Klotho is a lifespan-influencing gene expressed mainly in the kidneys. Soluble α-Klotho (αKL) is released into the circulation. In this study, we present baseline αKL serum levels of patients with acromegaly compared with controls with other pituitary adenomas and assess changes following transsphenoidal surg...
journal_title:European journal of endocrinology
pub_type: 杂志文章
doi:10.1530/EJE-12-1045
更新日期:2013-03-15 00:00:00
abstract:OBJECTIVE:Surgery remains a common form of treatment for sellar and parasellar tumors involving the pituitary gland and adjacent structures. Studies have suggested that pituitary surgery procedures performed at high-volume centers are associated with less adverse outcomes, yet it remains unclear which types of patients...
journal_title:European journal of endocrinology
pub_type: 杂志文章
doi:10.1530/EJE-09-0043
更新日期:2009-08-01 00:00:00
abstract::Previous reports of a correlation between serum dehydroepiandrosterone sulfate (DHEAS) and testosterone in both men and women have led to the suggestion that adrenal and gonadal secretion are related. In the present study, the correlation of DHEAS with testosterone and free testosterone (FT) in both normal men and wom...
journal_title:European journal of endocrinology
pub_type: 杂志文章
doi:10.1530/eje.0.1340201
更新日期:1996-02-01 00:00:00
abstract::The GH/IGF1 axis may play an important role in cognitive function. This theory is supported by the finding that both GH and IGF1 receptors are located in several brain areas such as the hippocampus, a brain area that is known to play an essential role in cognitive processes, especially memory and learning. However, th...
journal_title:European journal of endocrinology
pub_type: 杂志文章,评审
doi:10.1530/EJE-08-0279
更新日期:2008-12-01 00:00:00
abstract::Surgery is the treatment of choice for non-functioning pituitary macroadenomas (NFPAs). In cases of postoperative remnant growth or tumor recurrence, radiotherapy (RT) can be considered. The role of RT in the postoperative management of NFPAs is still debated. The main arguments against routine use of RT are the lack ...
journal_title:European journal of endocrinology
pub_type: 杂志文章,评审
doi:10.1530/EJE-19-0058
更新日期:2019-07-01 00:00:00
abstract:BACKGROUND AND OBJECTIVES:Testicular Leydig cell tumours (LCTs) are rare, steroid-secreting tumours. Elevated levels of aromatase (CYP19 or CYP19A1) mRNA have been previously described in LCTs; however, little is known about the mechanism(s) causing CYP19 over-expression. We report an LCT in a 29-year-old male with ele...
journal_title:European journal of endocrinology
pub_type: 杂志文章
doi:10.1530/EJE-11-0849
更新日期:2012-05-01 00:00:00
abstract:BACKGROUND:The aim was to evaluate changes of bone mineral density (BMD) and markers of bone turnover in healthy adolescents, and in adolescent users of combined oral contraceptives (COCs) with different ethinylestradiol (EE) contents. METHODS:In this prospective crossover study, 56 healthy females (15-19.5 years) wit...
journal_title:European journal of endocrinology
pub_type: 杂志文章,随机对照试验
doi:10.1530/EJE-11-1047
更新日期:2012-06-01 00:00:00
abstract:OBJECTIVE:To analyse trends in diagnostic practices of thyroid diseases and to relate them to the increase in thyroid cancer incidence in France over time. DESIGN:From 1980 to 2000, a French retrospective multicentric (three endocrinology and three nuclear medicine centres) study of thyroid diseases was conducted on 2...
journal_title:European journal of endocrinology
pub_type: 杂志文章,多中心研究
doi:10.1530/eje.0.1500133
更新日期:2004-02-01 00:00:00
abstract::As differentiated (follicular and papillary) thyroid cancer (DTC) may recur years after initial treatment, follow-up of patients with DTC is long term. However, this population has changed, with more individuals being discovered at an earlier stage of disease, so that previous follow-up protocols based mostly on data ...
journal_title:European journal of endocrinology
pub_type: 杂志文章
doi:10.1530/eje.0.1510539
更新日期:2004-11-01 00:00:00
abstract:BACKGROUND:Previous studies have demonstrated a high prevalence of thyroperoxidase antibodies (TPOAb) and autoimmune hypothyroidism in breast cancer (BC). These studies have been performed in BC patients generally 20-30 days after mastectomy. It is known that stress may have an influence on the immune system and a rela...
journal_title:European journal of endocrinology
pub_type: 杂志文章
doi:10.1530/eje.1.02108
更新日期:2006-05-01 00:00:00
abstract::Human growth hormone (GH) exists in a variety of isoforms. In the pituitary, the most abundant isoform is 22-kD GH (22 K GH), while other isoforms (non-22 K GH) are present in variable amounts. In human plasma, the GH heterogeneity contributes to the wide variability in GH levels measured by different immunoassays. Th...
journal_title:European journal of endocrinology
pub_type: 杂志文章
doi:10.1530/eje.0.1350573
更新日期:1996-11-01 00:00:00
abstract:INTRODUCTION:In genetically predisposed individuals, exogenous factors (including pollution) influence the development of Hashimoto's thyroiditis/chronic lymphocytic thyroiditis (CLT). CLT may also be a risk factor for associated thyroid cancer. Few data are available on the role of pollution from petrochemical complex...
journal_title:European journal of endocrinology
pub_type: 杂志文章
doi:10.1530/EJE-14-0864
更新日期:2015-04-01 00:00:00
abstract:OBJECTIVE:Identification and characterization of calcium-sensing receptor (CASR) mutations in four unrelated Italian kindreds with familial hypocalciuric hypercalcemia. DESIGN:Clinical evaluation and genetic analysis of CASR gene. Functional characterization of mutated CASRs. METHODS:Direct sequencing of CASR gene in...
journal_title:European journal of endocrinology
pub_type: 杂志文章
doi:10.1530/EJE-08-0798
更新日期:2009-03-01 00:00:00
abstract:BACKGROUND AND OBJECTIVES:Primary hyperparathyroidism (PHPT) is associated with increased cardiovascular mortality and morbidity. Little is known about hemostatic features of patients with PHPT. To our knowledge, plasma tissue factor pathway inhibitor (TFPI) and thrombin-activatable fibrinolysis inhibitor (TAFI) levels...
journal_title:European journal of endocrinology
pub_type: 杂志文章
doi:10.1530/EJE-09-0069
更新日期:2009-05-01 00:00:00
abstract:OBJECTIVE:Local 5'-deiodination of l-thyroxine (T(4)) to active thyroid hormone 3,3',5-tri-iodothyronine (T(3)) catalyzed by the two 5'-deiodinase enzymes (D1 and D2) regulates various T(3)-dependent functions in the anterior pituitary and has been well studied in rodents. Only limited information about deiodinase expr...
journal_title:European journal of endocrinology
pub_type: 杂志文章
doi:10.1530/eje.0.1470263
更新日期:2002-08-01 00:00:00
abstract:OBJECTIVE:GH causes insulin resistance, impairs glycemic control and increases the risk of vascular diabetic complications. Sulphonylureas stimulate GH secretion and this study was undertaken to investigate the possible stimulatory effect of repaglinide and nateglinide, two novel oral glucose regulators, on critical st...
journal_title:European journal of endocrinology
pub_type: 杂志文章
doi:10.1530/eje.0.1470133
更新日期:2002-07-01 00:00:00
abstract:OBJECTIVE:Evaluation of the efficiency of somatostatin analogues in the treatment of a mixed luteinizing hormone (LH)-, alpha-subunit-, prolactin (PRL)-secreting pituitary adenoma. DESIGN:A 30-year-old woman, with amenorrhaea-galactorrhaea, presented with a pituitary macroadenoma. The endocrine evaluation showed high ...
journal_title:European journal of endocrinology
pub_type: 杂志文章
doi:10.1530/eje.0.1450035
更新日期:2001-07-01 00:00:00
abstract::This study was designed to ascertain the long-term safety and efficacy profile of the somatostatin analogue octreotide as treatment of refractory acromegaly. Eight patients (aged 21-62 years) with persistent growth hormone (GH) elevation (duration 1-15 years) despite previous therapy were studied. Octreotide was given...
journal_title:European journal of endocrinology
pub_type: 临床试验,杂志文章
doi:10.1530/eje.0.1320429
更新日期:1995-04-01 00:00:00