Comparison of acid ethanol extraction and acid gel filtration prior to IGF-I and IGF-II radioimmunoassays: Improvement of determinations in acid ethanol extracts by the use of truncated IGF-I as radioligand

Bang, Peter; Eriksson, Urban; Sara, Vicki R.; Wivall, Inga-Lena; Hall, Kerstin

doi:10.1530/acta.0.1240620

Cited by 307 publications

(174 citation statements)

References 0 publications

Supporting

Mentioning

171

Contrasting

Unclassified

Order By: Relevance

“…Total IGF-I was measured after acid-ethanol extraction and cryoprecipitation, by RIA using human des(1-3)IGF-I tracer. 14 The intra-and interassay coefficients of variation were 4 and 11%, respectively. Mouse IGFBP-l was measured by immunoassay, as previously described.…”

Section: Hormonal Assaysmentioning

confidence: 95%

Gender difference in the leptin response to feeding in peroxisome-proliferator-activated receptor-alpha knockout mice

Brismar

2002

Int J Obes

View full text Add to dashboard Cite

OBJECTIVE: Peroxisome-proliferator-activated receptor-alpha (PPARa) has a central role in lipid metabolism. Mice lacking PPARa accumulate hepatic fat and are prone to late onset obesity. Leptin, an adipocyte-derived hormone, also plays an important role in regulating energy balance. In order to test the hypothesis that leptin secretion increases in response to PPARa knockout, we determined leptin concentrations including the effect of nutritional status in male and female PPARa knockout mice compared with wild-type controls. DESIGN: We studied the effect of 16 h fasting and 4 h refeeding on plasma leptin concentrations in male and female wild-type and PPARa-knockout mice, aged 14 weeks. In female mice the effect of daily growth hormone (GH) injection on the leptin response to refeeding was determined. RESULTS: Circulating leptin concentrations were higher in female mice compared with males and increased in both sexes after PPARa-knockout. There was no change in leptin levels after a 16 h fast, compared with ad libitum feeding. However leptin increased with refeeding, to the greatest extent in female PPARa-knockout mice. Intermittent GH administration decreased leptin concentrations in female, wild-type and PPARa-knockout animals and abolished the exaggerated leptin response to refeeding. CONCLUSIONS: Leptin concentrations are increased in PPARa-knockout mice. There are gender differences in the leptin response to feeding which may be due to differences in insulin sensitivity.

show abstract

Section: Hormonal Assaysmentioning

confidence: 95%

Gender difference in the leptin response to feeding in peroxisome-proliferator-activated receptor-alpha knockout mice

Brismar

2002

Int J Obes

View full text Add to dashboard Cite

show abstract

“…SUN measurements were available for 40 children (48%) on both occasions. Serum IGF-I concentrations were assessed by automated chemiluminescent immunoassay (IMMULITE 1000; DPC Biermann GmbH, Bad Nauheim, Germany) after pretreatment with acid (Bang et al, 1991). Inter-and intra-assay precision coefficient of variation (CV) were o9 and 3%, respectively.…”

Section: Measurementsmentioning

confidence: 99%

The effects of whole milk and infant formula on growth and IGF-I in late infancy

et al. 2009

View full text Add to dashboard Cite

Background/Objectives: High protein intake has been associated with increased growth. This may be linked to increased concentrations of insulin-like growth factor I (IGF-I), which seems to be influenced by the diet, especially its protein component. The short-term effects of high protein intake in late infancy are not known. The objective was to investigate the effects of high protein intake in the form of whole milk (WM) on growth and IGF-I from 9 to 12 months of age. Subjects/Methods: Healthy infants (n ¼ 83) were randomized to receive either WM or infant formula and fish oil or no fish oil (2 Â 2 design). Anthropometric variables, IGF-I concentrations, serum urea nitrogen (SUN) and diet were recorded before and after the intervention. Results: Intake of WM significantly increased the protein energy percentage (PE%; Pp0.001) and SUN (P ¼ 0.01), whereas there was no effect on size. The milk intervention increased IGF-I in boys (P ¼ 0.034) but not in girls. Intake of fish oil had no effect on the outcomes. Including all infants in the analysis there was a significant correlation between weight and IGF-I at 12 months (r ¼ 0.316, P ¼ 0.017), and PE% was positively associated with IGF-I after adjusting for sex and breastfeeding at both 9 (r ¼ 0.329, P ¼ 0.015) and 12 months (r ¼ 0.272, P ¼ 0.044). Conclusions: Randomization to WM had no overall effect on growth. However, the positive effect of WM on IGF-I in boys and the positive association between PE% intake and IGF-I at 9 and 12 months is consistent with the hypothesis that a high milk intake stimulates growth.

show abstract

“…Insulin-like growth factor-1 was analysed in EDTA plasma using the radio-immuno assay (RIA) method at the Endocrinological laboratory at the Karolinska Hospital, Stockholm, Sweden, as previously described by Bang et al (1991). Acid ethanol extraction followed by cryo-precipitation was used to separate insulin-like binding proteins (IGFBPs) from IGF-1 and decrease the interference of IGFBPs in the IGF-1 RIA.…”

Section: Insulin-like Growth Factor-1 Analysesmentioning

confidence: 99%

Insulin-like growth factor-1 (IGF1) genotype predicts breast volume after pregnancy and hormonal contraception and is associated with circulating IGF-1 levels: implications for risk of early-onset breast cancer in young women from hereditary breast cancer families

et al. 2005

View full text Add to dashboard Cite

BRCA1/2 mutations predispose to early-onset breast cancer, especially after oral contraceptive (OC) use and pregnancy. However, the majority of breast cancers might be due to more prevalent low-penetrance genes, which may also modify the risk in BRCA mutation carriers. The absence of the IGF1 19-repeat allele has been associated with high insulin-like growth factor-1 (IGF-1) levels during OC use. High IGF-1 levels are linked to early-onset breast cancer and larger breast volumes in the general population. The goal of this study was to elucidate the relationships between IGF1 genotype, early-onset breast cancer, breast volume, circulating IGF-1 levels and OC use in a prospective cohort of 258 healthy women p40 years old from high-risk breast cancer families. All women completed a questionnaire including information on reproductive factors and OC use. We measured the height, weight, breast volumes and plasma IGF-1 levels. IGF-1 levels were similar among parous and nulliparous women not using OCs. In all, 13% had no IGF1 19-repeat allele. There was an interaction between IGF1 genotype and OC use on IGF-1 levels (P ¼ 0.026) in nulliparous women and another interaction between IGF1 genotype and parity on breast volume (P ¼ 0.01). Absence of the 19-repeat allele was associated with high IGF-1 levels in nulliparous OC users and with larger breast volumes in parous women and OC users. Incident breast cancers were also more common in women without the 19-repeat allele (log rank P ¼ 0.002). Our results suggest that lack of the IGF1 19-repeat allele modifies IGF-1 levels, breast volume and possibly early-onset breast cancer risk after hormone exposure in young high-risk women.

show abstract

Comparison of acid ethanol extraction and acid gel filtration prior to IGF-I and IGF-II radioimmunoassays: Improvement of determinations in acid ethanol extracts by the use of truncated IGF-I as radioligand

Cited by 307 publications

References 0 publications

Gender difference in the leptin response to feeding in peroxisome-proliferator-activated receptor-alpha knockout mice

Gender difference in the leptin response to feeding in peroxisome-proliferator-activated receptor-alpha knockout mice

The effects of whole milk and infant formula on growth and IGF-I in late infancy

Insulin-like growth factor-1 (IGF1) genotype predicts breast volume after pregnancy and hormonal contraception and is associated with circulating IGF-1 levels: implications for risk of early-onset breast cancer in young women from hereditary breast cancer families

Contact Info

Product

Resources

About