Influence of insulin-like growth factor-binding protein-2 on plasma clearance and transfer of insulin-like growth factors-I and -II from plasma into mammary-derived lymph and milk of goats

1996 ◽  
Vol 150 (1) ◽  
pp. 121-127 ◽  
Author(s):  
C G Prosser ◽  
J Schwander
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
Plasma Clearance ◽  
Binding Protein ◽  
Plasma Concentrations ◽  
Insulin Like Growth Factor ◽  
Factor Binding ◽  
Lactating Goats ◽  
Igf I ◽  
Insulin Like Growth Factors

Abstract Plasma clearance of insulin-like growth factors-I and -II (IGF-I and -II) and insulin-like growth factor-binding protein-2 (IGFBP-2) from lactating goats (n=4) was determined following a single intravenous injection of the corresponding 125I-labelled human protein. Transfer of these proteins out of the vascular space was monitored by their subsequent appearance in mammary-derived lymph and milk. Clearance of 125I-IGFBP-2 from circulation was 0·37 ± 0·06 ml/min/kg, which is markedly greater than that of 125I-IGF-I or -II (0·11 ± and 0·12 ± 0·01 ml/min/kg respectively). This was also reflected in longer elimination half-lives for IGF-I (353 ± 6 min) and -II (254 ± 8 min) compared with IGFBP-2 (110 ± 9 min). Three hours after injection of the 125I-labelled protein, the plasma:lymph ratio of trichloroacetic acid-precipitable radioactivity was 1·54 ±0·04, 3·3 ±0·6 and 4·1 ±0·4 for IGFBP-2, IGF-I and -II respectively. The form of 125I-IGFBP-2 in lymph was not different from that of plasma. Elevation of plasma concentrations of IGFBP-2 by its intravenous infusion significantly decreased plasma half-life of both IGF-I and -II (251 ± 8 and 198 ±7 min respectively). Although the amount and rate of transfer of IGF into mammary-derived lymph was decreased slightly by IGFBP-2, concentrations eventually obtained were not different from control. However, secretion of IGFs into milk was significantly reduced by IGFBP-2, particularly in the case of IGF-I. These results are consistent with the ability of all three compounds to cross the vascular endothelium intact and of IGFBP-2 to decrease the uptake of IGF by mammary epithelium and subsequent secretion into milk. IGFBP-2 may well have acted to target plasma IGF towards non-mammary tissues, thus explaining the more rapid plasma clearance of IGFs in the presence of elevated IGFBP-2. Journal of Endocrinology (1996) 150, 121–127

scholarly journals Transferrin binds insulin-like growth factors and affects binding properties of insulin-like growth factor binding protein-3

FEBS Letters ◽  
2001 ◽  
Vol 509 (3) ◽  
pp. 395-398 ◽  
Author(s):  
Stephan Storch ◽  
Bernd Kübler ◽  
Stefan Höning ◽  
Michael Ackmann ◽  
Jürgen Zapf ◽  
...  
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
Binding Protein ◽  
Insulin Like Growth Factor ◽  
Binding Properties ◽  
Factor Binding ◽  
Insulin Like Growth Factors

scholarly journals Amblyomma americanumtick saliva insulin-like growth factor binding protein-related protein 1 binds insulin but not insulin-like growth factors

2015 ◽  
Vol 24 (5) ◽  
pp. 539-550 ◽  
Author(s):  
Ž. M. Radulović ◽  
L. M. Porter ◽  
T. K. Kim ◽  
M. Bakshi ◽  
A. Mulenga
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
Binding Protein ◽  
Insulin Like Growth Factor ◽  
Related Protein ◽  
Factor Binding ◽  
Insulin Like Growth Factors

Nutrient Balance and Stage of Lactation Affect Responses of Insulin, Insulin-Like Growth Factors I and II, and Insulin-Like Growth Factor-Binding Protein 2 to Somatotropin Administration in Dairy Cows

1991 ◽  
Vol 121 (10) ◽  
pp. 1656-1664 ◽  
Author(s):  
John L. Vicini ◽  
Frances C. Buonomo ◽  
Jeffrey J. Veenhuizen ◽  
Margaret A. Miller ◽  
David R. Clemmons ◽  
...  
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
Dairy Cows ◽  
Binding Protein ◽  
Nutrient Balance ◽  
Insulin Like Growth Factor ◽  
Factor Binding ◽  
Stage Of Lactation ◽  
Insulin Like Growth Factors

Insulin-like growth factor binding protein (IGFBP-3), an inhibitor of serum growth factors other than IGF-I and -II

1992 ◽  
Vol 153 (1) ◽  
pp. 15-21 ◽  
Author(s):  
L. Liu ◽  
J. Delbé ◽  
C. Blat ◽  
J. Zapf ◽  
L. Harel
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
Binding Protein ◽  
Insulin Like Growth Factor ◽  
Factor Binding ◽  
Igf I ◽  
Igfbp 3

scholarly journals Regulation of human villous trophoblast by insulin-like growth factors and insulin-like growth factor-binding protein-1

2004 ◽  
Vol 183 (3) ◽  
pp. 487-496 ◽  
Author(s):  
F A Hills ◽  
M G Elder ◽  
T Chard ◽  
M H F Sullivan
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
First Trimester ◽  
Insulin Like Growth Factor ◽  
Cell Numbers ◽  
Factor Binding ◽  
Villous Trophoblast ◽  
Igf I ◽  
Low Levels ◽  
Insulin Like Growth Factors

Many studies have implicated the insulin-like growth factors (IGFs) and insulin-like growth factor-binding protein-1 (IGFBP-1) in the control of the feto–maternal interface of human pregnancy, but many of the data are from cell lines derived from primary trophoblast or from extravillous trophoblast. We have obtained highly enriched villous cytotrophoblast (VCT) from first trimester and term human placentae, and investigated the effects of IGF-I, IGF-II and phosphoisoforms of IGFBP-1. First trimester villous trophoblast cells were regulated by all these factors. IGF-II increased cell numbers 3.5-fold after 96 h in culture, and IGF-I had less effect (1.5-fold increase) (both P<0.05). IGF-II also had a greater effect on the levels of matrix metalloproteinase (MMP)-2 and MMP-9. Phosphorylated and non-phosphorylated iso-forms of IGFBP-1 added alone increased cell numbers and MMP levels (P<0.05). IGFBP-1 did not modify the effects of IGF-II on cell numbers or on MMP production. Term VCT numbers and MMP production in vitro were unaffected by IGFs (P>0.05). Cell numbers were increased only by 100 nM IGFBP-1 isoforms (P<0.05), whereas MMP levels released from term cells were optimally increased by 1–10 nM IGFBP-1. Overall, our data show that IGFs regulate only first trimester, but not term, VCT. IGFBP-1 regulates VCT from both gestations, but the effects are concentration and end-point specific. In particular, first trimester cell numbers are more affected by low levels of IGFBP-1, whereas high levels of IGFBP-1 are needed to increase MMP and the converse applies to term VCT; low levels of IGFBP-1 have more effect on MMP levels.

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