scholarly journals Localization of binding sites for IGF-I, insulin and GH in the sow ovary

1999 ◽  
Vol 163 (2) ◽  
pp. 363-372 ◽  
Author(s):  
H Quesnel
Keyword(s):  
Granulosa Cells ◽  
Stromal Cells ◽  
Binding Sites ◽  
Binding Proteins ◽  
Cell Function ◽  
Type I ◽  
Thecal Cells ◽  
Igf I ◽  
Theca Externa ◽  
Theca Interna

Binding sites for IGF-I, insulin, and GH were localized by in situ binding of (125)I-labelled hormones to the different compartments of the sow ovary. Binding sites for IGF-I were detected in oocytes, granulosa and thecal cells of healthy and atretic follicles as well as in the antrum and the stroma. Competition of (125)I-labelled IGF-I with IGF-I, insulin and an analogue of IGF-I (Long R(3)IGF-I), which allowed discrimination between binding to binding proteins from binding to type-I receptors, suggested that type-I receptors were present in granulosa cells of healthy follicles, whilst binding in other compartments was mainly due to binding proteins. Binding of insulin was revealed in oocytes, granulosa and theca interna cells of healthy preantral and antral follicles, and, to a lesser extent, in theca externa and stromal cells, and was still observed in granulosa cells of atretic follicles. Labelling with (125)I-labelled bovine GH was demonstrated in oocytes, granulosa cells, theca interna cells, and, although less intense, in theca externa and stromal cells. It disappeared in granulosa cells during atresia. Binding sites for GH were detected at all follicular stages, from preantral to preovulatory stages, but the intensity of labelling in granulosa cells was more intense in preantral than in large follicles. These data support the participation of insulin, GH and IGF-I in oocyte maturation, follicular growth and stromal cell function in swine.

332. GYCOMIC ANALYSES OF THE GRANULOSA AND THECA OF BOVINE OVARIAN FOLLICLES

2010 ◽  
Vol 22 (9) ◽  
pp. 132
Author(s):  
N. Hatzirodos ◽  
J. Nigro ◽  
A. V. Vashi ◽  
H. F. Irving-Rodgers ◽  
B. Caterson ◽  
...  
Keyword(s):  
Granulosa Cells ◽  
Cell Function ◽  
Chondroitin Sulphate ◽  
Heparan Sulphate ◽  
Cell Types ◽  
Ovarian Follicles ◽  
Cell Type ◽  
Thecal Cells ◽  
Theca Externa

Development of ovarian follicles involves changes in cell function and remodelling of the follicular wall. Remodelling necessitates changes in the extracellular matrix, including proteoglycans (PGs). PGs contain glycosaminoglycans (GAGs) covalently bound to a protein core. The length of GAG chains in PGs and the degree and pattern of sulphation differs between cell types and change as cells alter their phenotype. PGs that have been identified in follicles include the chondroitin sulphate (CS) PG, versican and inter-a trypsin inhibitor, and the heparan sulphate (HS) PGs, perlecan and type XVIII collagen. The latter two are found in focimatrix, the follicular and the thecal subendothelial basal laminas. To examine GAGs composition in follicles, bovine antral follicles of various sizes were collected. Follicles were dissected and a biopsy taken for histological classification of health. Theca layers and granulosa cells were collected separately and analysed by fluorophore-assisted carbohydrate (FACE) analysis of GAGs following digestion to disaccharides with chondroitinase ABC, hyaluronidase, heparinase, and heparitinases I and II. Four non GAG sugars and 12 different GAG derived disaccharides were identified and quantitated on a per DNA basis. Healthy versus atretic follicles for each cell type were compared and correlation analyses were also undertaken. Immunohistochemistry using CS specific antibodies was also conducted. There was no effect of size on the GAG content for either granulosa or theca cells. The 4- and 6- sulphated CS sugars were the most abundant following digestion in all tissues. Theca had higher levels than granulosa cells of HS derived disaccharides and also of un- or 4- or 6- N-sulphated CS derived disaccharides. Some sulphated CS moieties localised uniquely to the stroma surrounding blood vessels in the theca externa. Atretic follicles had lower amounts of disaccharides derived from HS in both granulosa and thecal cells, suggesting that heparanase may be activated upon atresia.

scholarly journals Scavenger Receptor Class B Type I in the Rat Ovary: Possible Role in High Density Lipoprotein Cholesterol Uptake and in the Recognition of Apoptotic Granulosa Cells*

Endocrinology ◽  
1999 ◽  
Vol 140 (6) ◽  
pp. 2494-2500 ◽  
Author(s):  
Per-Arne Svensson ◽  
Magnus S. C. Johnson ◽  
Charlotte Ling ◽  
Lena M. S. Carlsson ◽  
Håkan Billig ◽  
...  
Keyword(s):  
High Density Lipoprotein ◽  
Granulosa Cells ◽  
High Density Lipoprotein Cholesterol ◽  
Scavenger Receptor ◽  
Density Lipoprotein ◽  
High Density ◽  
Lipoprotein Cholesterol ◽  
Type I ◽  
Anionic Phospholipids ◽  
Thecal Cells

Abstract Scavenger receptor class B type I (SR-BI) mediates the selective uptake of high density lipoprotein cholesterol. SR-BI is expressed at high levels in the ovary, indicating that it plays a role in the delivery of cholesterol as substrate for steroid hormone production. However, SR-BI also binds anionic phospholipids with high affinity and could therefore be involved in the recognition of apoptotic cells. In this study we have characterized the expression of SR-BI in rat ovarian follicles undergoing atresia. Atretic follicles with cells undergoing apoptosis were identified by in situ DNA end labeling, and SR-BI expression was determined by in situ hybridization and immunohistochemistry. SR-BI was expressed in thecal cells at all stages of follicular development, including atretic follicles, and in corpus luteum. Isolated apoptotic granulosa cells (but not viable granulosa cells) bound annexin V, indicating that they display anionic phospholipids on the cell surface. Transfection of COS-7 cells with an expression vector carrying the rat SR-BI complementary DNA resulted in increased binding to apoptotic granulosa cells (46 ± 2% of the SR-BI-expressing cells bound at least one granulosa cell compared with 24 ± 3% for the mock-transfected cells; P < 0.0001), whereas the binding to viable granulosa cells was unchanged. Apoptotic granulosa cells also bound to isolated thecal shells. We conclude that thecal cells of both nonatretic and atretic follicles express SR-BI. The location of SR-BI expression in the ovary supports a role of this receptor in the uptake of high density lipoprotein cholesterol. In addition, our data suggest that SR-BI mediates the recognition of apoptotic granulosa cells by the surrounding thecal cells and that it therefore may play a role in the remodeling of atretic follicles to secondary interstitial cells.

Ultrastructural observations of previtellogenic ovarian follicles of dove

Zygote ◽  
2004 ◽  
Vol 12 (4) ◽  
pp. 285-292 ◽  
Author(s):  
Otilia Zarnescu
Keyword(s):  
Electron Microscopy ◽  
Granulosa Cells ◽  
Ovarian Follicle ◽  
Complex Structure ◽  
Cortical Region ◽  
Multivesicular Bodies ◽  
Coated Pits ◽  
Zona Radiata ◽  
Theca Externa ◽  
Theca Interna

Dove ovarian follicle is a complex structure composed of oocyte surrounded by a somatic compartment consisting of theca externa, theca interna and granulosa. The structure of ovarian follicle (1 and 2 mm) of dove was studied by electron microscopy. The granulosa was pseudostratified in the 1-mm-diameter follicles and stratified with two or three irregular rows of cells in the 2-mm-diameter follicles. In the larger follicle indentations between oocyte and granulosa cells become more numerous and the microvilli of granulosa cell elongated to form a zona radiata with similarly elongated oocyte microvilli. Lining bodies were present at the tips of granulosa microvilli and in the cortical region of the oocyte. In the oocyte cortex were observed coated pits, coated vesicles, dense tubules, multivesicular bodies and primordial yolk spheres. Primordial yolk spheres may contain lining bodies and were observed fused with dense tubules and multivesicular bodies or associated with smooth cisternae.

Insulin-like growth factor I enhancement of steroidogenesis by bovine granulosa cells and thecal cells: dependence on de novo cholesterol synthesis

1996 ◽  
Vol 151 (3) ◽  
pp. 365-373 ◽  
Author(s):  
L J Spicer ◽  
T D Hamilton ◽  
B E Keefer
Keyword(s):  
Granulosa Cells ◽  
Cholesterol Synthesis ◽  
De Novo ◽  
Side Chain ◽  
Side Chain Cleavage ◽  
Chain Cleavage ◽  
Thecal Cells ◽  
Igf I ◽  
Cleavage Enzyme ◽  
Coa Reductase

Abstract Studies were conducted to determine the importance of de novo cholesterol synthesis and cholesterol side-chain cleavage enzyme in the action of IGF-I in bovine granulosa and thecal cells. Granulosa and thecal cells from bovine follicles were cultured for 2 days in 10% fetal calf serum and then treated with luteinizing hormone (100 ng/ml) and IGF-I (0 or 100 ng/ml) for an additional 2 days in serum-free medium. During the last 24 h of treatment, cells were concomitantly treated with simvastatin (0, 0·5 or 5 μg/ml) or 25-hydroxycholesterol (0 or 10 μg/ml). Simvastatin, a potent inhibitor of the key enzyme controlling de novo cholesterol synthesis, 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase, completely inhibited (P<0·05) progesterone production by granulosa cells and progesterone and androstenedione production by thecal cells. Simvastatin also inhibited (P<0·05) granulosa cell and thecal cell proliferation. Concomitant treatment with mevalonate, an immediate product of HMG-CoA reductase, attenuated the inhibitory effect of simvastatin on progesterone and androstenedione production by thecal cells and blocked the inhibitory effect of simvastatin on cell proliferation. The addition of 25-hydroxycholesterol, a substrate for cholesterol side-chain cleavage enzyme, had no effect (P>0·10) on IGF-I-stimulated progesterone or androstenedione production by thecal cells and actually inhibited (P<0·05) IGF-I-stimulated progesterone production by granulosa cells. These results provide indirect evidence indicating that stimulation of HMG-CoA reductase is an important locus of IGF-I action in bovine granulosa and thecal cells, whereas IGF-I has little or no effect on side-chain cleavage enzyme activity in these same cell types under the culture conditions employed. Journal of Endocrinology (1996) 151, 365–373

Characterization of transforming growth factor-α receptors in the avian ovary: alterations in ligand binding to granulosa cells during follicular maturation

1996 ◽  
Vol 149 (1) ◽  
pp. 171-179 ◽  
Author(s):  
O M Onagbesan ◽  
I Woolveridge ◽  
M J Peddie
Keyword(s):  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Granulosa Cells ◽  
Binding Sites ◽  
Transforming Growth Factor ◽  
Transforming Growth Factor Α ◽  
Follicular Maturation ◽  
Igf I ◽  
Epidermal Growth ◽  
Factor Α

Abstract The presence of epidermal growth factor receptors (EGF-R) and the ligands epidermal growth factor/transforming growth factor-α (EGF/TGFα) have been reported in mammalian ovaries where they are implicated in folliculogenesis and steroidogenesis. Evidence is presented to show that authentic EGF/TGFα receptors are expressed by the avian granulosa cells. The TGFα receptors (TGFα-R) from chicken granulosa cells were characterized by specific binding of 125I-human TGFα. In this study, competition with human EGF, human TGFα, human IGF-I, human basic fibroblast growth factor (bFGF) and insulin for 125I-human TGFα binding demonstrated that the avian granulosa cell TGFα-R binds human EGF with 300-fold lower affinity than human TGFα. IGF-I, bFGF and insulin did not displace bound 125I-TGFα. Scatchard analysis showed that a single class of high-affinity binding sites is present on the granulosa cells (Kd 0·23 ± 0·009 nm). However, the number of binding sites altered during follicular maturation with a significant decline in the most mature follicle. These results go some way to explaining the basis for the changing sensitivity of avian granulosa cells to EGF/TGFα stimulation as they mature. In addition, the gonadotrophins, LH and FSH, increased the number of receptors in cultured granulosa cells and may therefore partially influence folliculogenesis and steroidogenesis through this route. Journal of Endocrinology (1996) 149, 171–179

Differential binding of 125I-IGF-I preparations to human fibroblast monolayers

1988 ◽  
Vol 118 (4) ◽  
pp. 513-520 ◽  
Author(s):  
C. A. Conover ◽  
P. Misra ◽  
R. L. Hintz ◽  
R. G. Rosenfeld
Keyword(s):  
Binding Sites ◽  
Human Fibroblast ◽  
Type I ◽  
Type Ii ◽  
Low Concentrations ◽  
Type I Igf Receptor ◽  
Igf I ◽  
Differential Binding ◽  
Igf Receptor ◽  
Binding Curves

Abstract. Specific, high affinity binding of 125I-IGF-I to the type I IGF receptor on human fibroblast monolayers was not altered by varying feeding schedules, serum lots, washing procedures, or incubation times and temperatures. However, markedly different competitive binding curves were obtained when different iodinated IGF-I preparations were used. Five of six radioligands bound preferentially to the type I IGF receptor on human fibroblast monolayers, with 50% displacement at 4–8 μg/l unlabelled IGF-I; with one radioligand a paradoxical 20–200% increase in 125I-IGF-I binding was observed at low concentrations of unlabelled IGF-I, while concentrations as high as 100 μg/l IGF-I failed to displace this radioligand. The latter binding pattern cannot be accounted for by 125I-IGF-I binding to the type II IGF receptor. These data indicate that various radioligands may have preferential affinities for different IGF-I binding sites on human fibroblast monolayers.

Production of insulin-like growth factor I (IGF-I) and IGF-binding proteins by rat intestinal stromal cells in vitro

1998 ◽  
Vol 54 (2) ◽  
pp. 158-166
Author(s):  
R. G. MacDonald ◽  
R. H. McCusker ◽  
D. J. Blackwood ◽  
J. A. Vanderhoof ◽  
J. H. Y. Park
Keyword(s):  
Growth Factor ◽  
Stromal Cells ◽  
Binding Proteins ◽  
Insulin Like Growth Factor ◽  
Igf Binding Proteins ◽  
Factor I ◽  
Igf I ◽  
Igf Binding ◽  
Growth Factor I

226. Expression of matrix metalloproteinases in bovine thecal cells

2005 ◽  
Vol 17 (9) ◽  
pp. 88
Author(s):  
L. Harland ◽  
H. F. Irving-Rodgers ◽  
S. E. Morris ◽  
R. J. Rodgers
Keyword(s):  
Extracellular Matrix ◽  
Matrix Metalloproteinases ◽  
Phorbol Ester ◽  
Granulosa Cells ◽  
Gelatin Zymography ◽  
Mrna Levels ◽  
Cell Culture Systems ◽  
Thecal Cells ◽  
Theca Interna ◽  
Free Media

As follicles grow the thecal layers expand. It is likely that extracellular matrix is remodelled in this process and possibly by matrix metalloproteinases (MMPs). A promising candidate to regulate MMPs is insulin-like factor 3 (INSL3). It is produced by thecal cells, its receptor, LGR8, is expressed in the theca interna (unpublished) and a related molecule, relaxin, regulates turnover of matrix in a number of tissues. For this reason we sort to examine the role of INSL3 in matrix turnover. However, in all thecal cell culture systems examined LGR8 receptors appear to be down regulated within 24 h. We therefore examined the effects of second messenger pathway activators. Thecal and granulosa cells were isolated and cultured and the levels of RNA for MMP2 and 9 quantitated by RT-PCR. MMP2 mRNA levels in thecal tissues were >10 fold higher than in granulosa cells (n = 19 follicles >10 mm). MMP2 levels were substantially greater than MMP9. At 12 h phorbol ester (100 nM phorbol 12,13-didecanoate) increased thecal expression of MMP 9 mRNA levels 11.5 fold (P < 0.001) and at 48 h MMP2 mRNA was increased 5 fold (P < 0.01). Pieces of whole follicle wall [follicles <5 mm in diameter, classified as healthy (n = 12) or atretic (n = 6)] were cultured in serum free media. Expression of the steroidogenic enzymes 17β HSD and P450scc but not 3β HSD were detected by immunohistochemistry even after 10 days. MMP activity on day 2 was analysed by gelatin zymography. Treatment with phorbol ester increased active MMP9 19 fold (P < 0.001). Treatment of thecal cells or follicle walls with 1 mM dibutyryl cAMP induced additional MMP activities at sizes of 110 and 122kDa. No effects on MMP2 activity were observed. In conclusion whilst we do not know the ligand inducers of the synthesis and activator of MMPs in thecal cells they can be regulated. Hence MMPs are candidates for remodelling the extracellular matrix of thecal layers.

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