IGF-I stimulates granulosa cell-derived insulin-like growth factor binding protein-5: evidence for medication via type I IGF receptors

1994 ◽  
Vol 99 (2) ◽  
pp. 279-284 ◽  
Author(s):  
Eli Y. Adashi ◽  
Carol E. Resnick ◽  
Ron G. Rosenfeld
Keyword(s):  
Growth Factor ◽  
Granulosa Cell ◽  
Binding Protein ◽  
Type I ◽  
Insulin Like Growth Factor ◽  
Factor Binding ◽  
Igf Receptors ◽  
Igf I

An acid-stable insulin-like growth factor (IGF)-binding protein from pig serum inhibits binding of IGF-I and IGF-II to vascular endothelial cells

1989 ◽  
Vol 120 (2) ◽  
pp. 231-236 ◽  
Author(s):  
R. Gopinath ◽  
P. E. Walton ◽  
T. D. Etherton
Keyword(s):  
Endothelial Cells ◽  
Growth Factor ◽  
Binding Protein ◽  
Type I ◽  
Insulin Like Growth Factor ◽  
Igf Receptors ◽  
Igf I ◽  
Igf Binding ◽  
Igf Binding Protein ◽  
Acid Stable

ABSTRACT The effects of a porcine insulin-like growth factor (IGF)-binding protein on binding of IGF-I and IGF-II to porcine aortic endothelial cells (PAEC) were determined. Binding of 125I-labelled IGF-I and -II to IGF receptors was inhibited by IGF-binding protein. IGF-binding protein inhibited binding of IGF-I and -II in a dose-dependent manner with half-maximal inhibition occurring at 5·43 and 108 μg/l respectively. A125I-labelled IGF-I–IGF-binding protein complex, formed by incubating 125I-labelled IGF-I with IGF-binding protein overnight at 4 °C, did not effectively bind to endothelial IGF receptors. Addition of IGF-binding protein to PAEC previously incubated with IGF-I caused a marked dissociation of bound IGF-I (47% dissociation within 12 h). These results indicate that the acid-stable IGF-binding protein which appears to be a part of the 150 kDa GH-dependent binding protein, blocks binding of IGF-I and -II by the IGF receptors and appears to exhibit a higher affinity for IGF-I than the endothelial type-I IGF receptor. The ramifications of this latter point with respect to transfer of circulating IGFs (bound to their IGF-binding proteins) across the vascular endothelium are not clear. Journal of Endocrinology (1989) 120, 231–236

Insulin-like growth factor binding protein-3 inhibits porcine granulosa cell function in vitro

1995 ◽  
Vol 268 (6) ◽  
pp. E1057-E1064
Author(s):  
S. E. Samaras ◽  
J. M. Hammond
Keyword(s):  
Growth Factor ◽  
Granulosa Cell ◽  
Granulosa Cells ◽  
Cell Function ◽  
Binding Protein ◽  
Insulin Like Growth Factor ◽  
Factor Binding ◽  
Porcine Granulosa Cells ◽  
Igf I ◽  
Igfbp 3

Recombinant human insulin-like growth factor binding protein-3 (rhIGFBP-3) effects on basal, insulin-like growth factor I (IGF-I)-, and follicle-stimulating hormone (FSH)-stimulated progesterone (P4) secretion and [3H]aminoisobutyric acid (AIB) uptake by primary porcine granulosa cells (MDGs) and MDGs that have been passaged once (MDGp1) were assessed. Cells were treated concurrently or were preincubated with rhIGFBP-3 followed by treatment. rhIGFBP-3 had no effect on MDG or MDGp1 cell numbers after 24 h. Cotreatment with rhIGFBP-3 inhibited P4 secretion after treatment with FSH, IGF-I, and FSH plus IGF-I. FSH did not stimulate [3H]AIB uptake. However, the IGF-I-stimulated increase in [3H]AIB uptake was completely prevented by concurrent treatment with IGFBP-3. Preincubation of MDGp1 cells with IGFBP-3 dose dependently inhibited FSH- and IGF-I-stimulated P4 secretion. This inhibition was associated with increased cell association of the binding protein and increased IGF-I binding to the cells. These results indicate that IGFBP-3 is inhibitory to a variety of crucial functions in porcine granulosa cells, supporting a role for it in the regulation of granulosa cell function.

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

Rat Ovarian Insulin-Like Growth Factor Binding Protein-4: A Hormone-Dependent Granulosa Cell-Derived Antigonadotropin

1997 ◽  
Vol 4 (3) ◽  
pp. 144-151 ◽  
Author(s):  
Lechoslaw Putowski ◽  
Richard M. Rohan ◽  
Doo Seok Choi ◽  
Wendy J. Scherzer ◽  
Elisabetta Ricciarelli ◽  
...  
Keyword(s):  
Growth Factor ◽  
Granulosa Cell ◽  
Binding Protein ◽  
Insulin Like Growth Factor ◽  
Factor Binding

Characterization and Hormonal Regulation of Granulosa Cell-Derived Insulin-Like Growth Factor Binding Protein-4

1996 ◽  
Vol 3 (3) ◽  
pp. 145-151 ◽  
Author(s):  
DooSeok Choi ◽  
Lechoslaw T. Putowski ◽  
Paul J. Fielder ◽  
Ron G. Rosenfeld ◽  
Richard M. Rohan ◽  
...  
Keyword(s):  
Growth Factor ◽  
Granulosa Cell ◽  
Hormonal Regulation ◽  
Binding Protein ◽  
Insulin Like Growth Factor ◽  
Factor Binding
Sign in / Sign up

Export Citation Format

Share Document