scholarly journals Inhibin removes the inhibitory effects of activin on steroid enzyme expression and androgen production by normal ovarian thecal cells

2011 ◽  
Vol 48 (1) ◽  
pp. 49-60 ◽  
Author(s):  
J M Young ◽  
A S McNeilly
Keyword(s):  
Culture System ◽  
Regulatory Protein ◽  
Theca Cell ◽  
Cell Culture System ◽  
Inhibitory Effects ◽  
Enzyme Expression ◽  
Serum Free ◽  
Theca Cells ◽  
Thecal Cells ◽  
Steroidogenic Acute Regulatory

Activin and inhibin are important local modulators of theca cell steroidogenesis in the ovary. Using a serum-free primary theca cell culture system, this study investigated the effects of inhibin on theca cell androgen production and expression of steroidogenic enzymes. Androstenedione secretion from theca cells cultured in media containing activin, inhibin and follistatin was assessed by RIA over 144 h. Activin (1–100 ng/ml) suppressed androstenedione production. Inhibin (1–100 ng/ml) blocked the suppressive effects of added activin, but increased androstenedione production when added alone, suggesting it was blocking endogenous activin produced by theca cells. Addition of SB-431542 (activin receptor inhibitor) and follistatin (500 ng/ml) increased androstenedione production, supporting this concept. Infection of theca cells with adenoviruses expressing inhibitory Smad6 or 7 increased androstenedione secretion, confirming that the suppressive effects of activin required activation of the Smad2/3 pathway. Activin decreased the expression levels of steroidogenic acute regulatory protein (STAR), whereas STAR expression was increased by inhibin and SB-431542, alone and in combination. CYP11A was unaffected. The expression of CYP17 encoding 17α-hydroxylase was unaffected by activin but increased by inhibin and SB-431542, and when added in combination the effect was further enhanced. The expression of 3β-hydroxysteroid dehydrogenase (3β-HSD) was significantly decreased by activin, while inhibin alone and in combination with SB-431542 both potently increased the expression of 3β-HSD. In conclusion, activin suppressed theca cell androstenedione production by decreasing the expression of STAR and 3β-HSD. Inhibin and other blockers of activin action reversed this effect, supporting the concept that endogenous thecal activin modulates androgen production in theca cells.

Differential regulation of pig theca cell steroidogenesis by LH, insulin-like growth factor I and granulosa cells in serum-free culture

Reproduction ◽  
2000 ◽  
pp. 211-219 ◽  
Author(s):  
EM Shores ◽  
HM Picton ◽  
MG Hunter
Keyword(s):  
Granulosa Cells ◽  
Culture System ◽  
Theca Cell ◽  
Serum Free ◽  
Theca Cells ◽  
Plating Density ◽  
Factor I ◽  
Viable Cells ◽  
Igf I ◽  
Oestradiol Production

The regulation of pig theca cell steroidogenesis was studied by the development of a physiological serum-free culture system, which was subsequently extended to investigate potential theca-granulosa cell interactions. Theca cells were isolated from antral follicles 6-9 mm in diameter and the effects of plating density (50-150x10(3) viable cells per well), LH (0.01-1.0 ng ml(-1)), Long R3 insulin-like growth factor I (IGF-I) (10, 100 ng ml(-1)) and insulin (1, 10 ng ml(-1)) on the number of cells and steroidogenesis were examined. The purity of the theca cell preparation was verified biochemically and histologically. Co-cultures contained 50x10(3) viable cells per well in granulosa to theca cell ratio of 4:1. Wells containing granulosa cells only were supplemented with 'physiological' doses of androstenedione or 100 ng ml(-1). Oestradiol production by co-cultures was compared with the sum of the oestradiol synthesized by granulosa and theca cells cultured separately. Oestradiol and androstenedione production continued throughout culture. High plating density decreased steroid production (P < 0.01). LH increased androstenedione (P < 0.001) and oestradiol (P < 0.05) synthesis and the sensitivity of the cells increased with time in culture. Oestradiol production was increased by 10 ng IGF-I ml(-1) (P < 0.001) but androstenedione required 100 ng ml(-1) (P < 0.001). Co-cultures produced more oestradiol than the sum of oestradiol synthesized by theca and granulosa cells cultured separately (P < 0. 001), irrespective of the androstenedione dose. This serum-free culture system for pig theca cells maintained in vivo steroidogenesis and gonadotrophin responsiveness. Thecal androstenedione and oestradiol production were differentially regulated and were primarily stimulated by LH and IGF-I, respectively. Theca-granulosa cell interactions stimulated oestradiol synthesis and this interaction was mediated by factors additional to the provision of thecal androgen substrate to granulosa cells.

Effect of melatonin on bovine theca cells in vitro

2018 ◽  
Vol 30 (4) ◽  
pp. 643 ◽  
Author(s):  
T. Feng ◽  
L. F. Schutz ◽  
B. C. Morrell ◽  
M. C. Perego ◽  
L. J. Spicer
Keyword(s):  
Cell Proliferation ◽  
Cytochrome P450 ◽  
Ovarian Function ◽  
Cell Function ◽  
Regulatory Protein ◽  
Theca Cell ◽  
Theca Cells ◽  
Dependent Inhibition ◽  
Steroidogenic Acute Regulatory

Melatonin affects granulosa cell function in several species but its function in theca cells is less clear, particularly in monotocous animals. Thus, the objectives of this study were to determine the effects of melatonin on theca cell steroidogenesis, gene expression and cell proliferation in a monotocous species, namely cattle. Ovaries were collected from a local bovine abattoir, from which theca cells were isolated from large (8–22 mm) follicles and treated with various hormones in serum-free medium for 24 h or 48 h. Melatonin caused a dose-dependent inhibition (P < 0.05) of LH+insulin-like growth factor 1 (IGF1)-induced androstenedione and progesterone production. Also, melatonin inhibited (P < 0.05) LH+IGF1-induced expression of steroidogenic acute regulatory protein (StAR) mRNA (via real-time polymerase chain reaction) in theca cells, but it had no effect (P > 0.10) on cytochrome P450 11A1 (CYP11A1) and cytochrome P450 17A1 (CYP17A1) mRNA abundance. In LH+IGF1-treated theca cells, melatonin decreased caspase 3 (CASP3) mRNA to levels similar to those observed in LH-treated theca cells. In contrast, melatonin increased (P < 0.05) the number of bovine theca cells in both LH- and LH+IGF1-treated cultures. In conclusion, melatonin may act as an endocrine regulator of ovarian function in cattle by stimulating theca cell proliferation and inhibiting differentiation via inhibition of hormone-induced steroidogenesis.

Serum-free cell culture system supplemented with lipid-rich albumin for hepatitis C virus (strain O of genotype 1b) replication

2007 ◽  
Vol 125 (2) ◽  
pp. 162-168 ◽  
Author(s):  
Ken-ichi Abe ◽  
Masanori Ikeda ◽  
Yasuo Ariumi ◽  
Hiromichi Dansako ◽  
Nobuyuki Kato
Keyword(s):  
Cell Culture ◽  
Hepatitis C Virus ◽  
Hepatitis C ◽  
Virus Strain ◽  
Culture System ◽  
Free Cell ◽  
Cell Culture System ◽  
Serum Free ◽  
Genotype 1B

scholarly journals Development of an experimental ovarian tumor: immunocytochemical analysis

2002 ◽  
pp. 387-395 ◽  
Author(s):  
E Sorianello ◽  
S Fritz ◽  
C Beyer ◽  
DB Hales ◽  
A Mayerhofer ◽  
...  
Keyword(s):  
Granulosa Cells ◽  
Regulatory Protein ◽  
Tumor Development ◽  
Female Rats ◽  
Nuclear Antigen ◽  
Normal Ovary ◽  
Rt Pcr ◽  
Thecal Cells ◽  
Junction Protein ◽  
Steroidogenic Acute Regulatory

OBJECTIVE: The aim of the present work was to study whether immunocytochemical parameters present in the normal ovary were altered after tumor development under high gonadotropin levels. METHODS: Ovarian tumors (luteoma): castrated female rats had an ovary grafted into the spleen; tumors were left to develop for 1, 2, 3 or 7 months. The presence of apoptotic cells (TUNEL method) and the expression of proliferating cell nuclear antigen (PCNA), gap junction protein (Cx43), steroidogenic acute regulatory protein (StAR), aromatase and synaptosome-associated protein of 25 kDa (SNAP-25) were determined by immunocytochemistry. Some of these findings were confirmed by RT-PCR (Cx43, StAR, SNAP-25). Inhibin subunit mRNAs were investigated by Northern blot. RESULTS: PCNA staining of tumors was mainly found in granulosa cells of transforming follicles and was absent from luteinized follicles. A nearly complete absence of apoptosis was observed. Cx43 was mainly found in follicles, while it was very weakly expressed or absent in luteinized follicles. StAR protein expression, indicating active steroidogenesis, was demonstrated only in luteinized follicles and in thecal cells, but was absent from granulosa cells. Aromatase immunoreactivity was very intense in granulosa and also present in luteal cells. Membrane-associated and cytoplasmic SNAP-25 immunostaining was determined in patches of endocrine cells in the follicles, as well as in the luteinized follicles. The expression of mRNAs for Cx43, StAR and SNAP-25 (RT-PCR) and inhibin subunits (Northern blots) were confirmed in 1-, 3- and 7-month-old tumors. CONCLUSIONS: These results indicated that luteoma most likely develop from unruptured follicles by hypertrophy and proliferation of follicular cells. Circulating gonadotropins seem to play a fundamental role in maintaining the expression of proteins typically expressed in normal ovary, while avoiding apoptosis in this tissue.

scholarly journals Differential Sensitivities of Chlamydia trachomatis Strains to Inhibitory Effects of Gamma Interferon

2000 ◽  
Vol 68 (10) ◽  
pp. 6038-6040 ◽  
Author(s):  
Richard P. Morrison
Keyword(s):  
Cell Culture ◽  
Host Defense ◽  
Culture System ◽  
Chlamydial Infection ◽  
Gamma Interferon ◽  
Cell Culture System ◽  
Inhibitory Effects ◽  
Ifn Γ ◽  
Important Cytokine

ABSTRACT Gamma interferon (IFN-γ) is an important cytokine in host defense against chlamydial infection. An in vitro cell culture system was used to show that IFN-γ inhibition of chlamydial growth, as determined by diminished recovery of infectious elementary bodies, differed markedly among chlamydial strains. These differences in sensitivity among chlamydial strains to IFN-γ-mediated inhibition may profoundly influence the clinical outcome of infection.

Generation of murine bone marrow derived macrophages in a standardised serum-free cell culture system

2009 ◽  
Vol 342 (1-2) ◽  
pp. 13-19 ◽  
Author(s):  
Kristin Eske ◽  
Katrin Breitbach ◽  
Jens Köhler ◽  
Patimaporn Wongprompitak ◽  
Ivo Steinmetz
Keyword(s):  
Cell Culture ◽  
Bone Marrow ◽  
Culture System ◽  
Free Cell ◽  
Cell Culture System ◽  
Serum Free ◽  
Murine Bone Marrow

scholarly journals Interaction of bovine granulosa and theca cells in a novel serum-free co-culture system

Reproduction ◽  
2003 ◽  
pp. 527-538 ◽  
Author(s):  
C Allegrucci ◽  
MG Hunter ◽  
R Webb ◽  
MR Luck
Keyword(s):  
Cell Survival ◽  
Culture System ◽  
Close Contact ◽  
Cell Phenotype ◽  
Serum Free ◽  
Theca Cells ◽  
Plating Density ◽  
Igf I ◽  
Defined Culture ◽  
Cell Plating

The objective of this study was to develop a defined culture system in which bovine follicular and granulosa cells are grown in close contact with each other and with the extracellular matrix (ECM) component laminin. Granulosa and theca cells from follicles 4-6 mm in diameter were cultured on either side of laminin-coated BioCoat cell culture inserts in a serum-free medium containing 10 ng insulin ml(-1) at plating densities of 10(5) and 3 x 10(5) cells per membrane side. The cells adopted a clumped arrangement, maintained steroidogenic activity for at least 7 days and demonstrated paracrine communication by increased steroidogenesis and enhanced cell survival compared with cells in mono-culture. Co-cultured theca cells secreted significantly more androstenedione compared with cells in mono-culture. Granulosa cell viability was doubled by co-culture with theca cells. Co-cultures at both cell plating densities were responsive to treatment with physiological combinations of either FSH, LH and LR3 insulin-like growth factor I (IGF-I) (treatment A) or FSH, LR3 IGF-I and androstenedione (treatment B). Significantly more androstenedione was secreted in the presence of treatment A compared with controls. In contrast, oestradiol secretion was increased only by treatment B. Progesterone secretion was unaffected by treatment and did not increase during culture. Co-cultures at the higher plating density demonstrated higher theca cell survival and better maintenance of the follicular cell phenotype. In conclusion, this novel co-culture system provides a unique model for the study of paracrine communication between ovarian somatic cells and cell-ECM interactions during follicle growth.

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