EurekaMag.com logo
+ Site Statistics
References:
52,654,530
Abstracts:
29,560,856
PMIDs:
28,072,755
+ Search Articles
+ Subscribe to Site Feeds
EurekaMag Most Shared ContentMost Shared
EurekaMag PDF Full Text ContentPDF Full Text
+ PDF Full Text
Request PDF Full TextRequest PDF Full Text
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter
Follow on LinkedInFollow on LinkedIn

+ Translate

Hormone induction of ascorbic acid transport in immature granulosa cells



Hormone induction of ascorbic acid transport in immature granulosa cells



Endocrinology 137(10): 4316-4321



Ascorbic acid serves a vital role as an antioxidant, and like FSH, it inhibits apoptosis of granulosa cells in cultured follicles. In contrast, reactive oxygen species block the action of FSH and induce DNA damage in these cells. As the uptake of ascorbic acid by granulosa cells may be a site for regulation, we examined the nature of this process and whether uptake is under hormone control. Granulosa cells were isolated from immature rats pretreated with estradiol or diethylstilbestrol for 3-4 days and placed in culture. Culture of the cells with either FSH (50 ng/ml) or insulin-like growth factor I (IGF-I; 30 ng/ml) for 48 h increased ascorbic acid uptake by 2.7- and 1.9-fold (P < 0.05), respectively, and the response to FSH plus IGF-I was additive (4.5-fold; P < 0.05). The interval for maximum induction of ascorbic acid transport by FSH was between 4-8 h, whereas a significant response to IGF-I was not seen until 48 h. GnRH (1 microM), phorbol ester (phorbol 12-myristate 13-acetate; 1 microM), and 8-bromo-cAMP (8Br-cAMP; 1 mM) also induced ascorbic acid transport by 1.7-, 1.9-, and 2.3-fold (P < 0.05) within 24 h, and the response to maximal levels of phorbol ester and 8Br-cAMP was synergistic (4.8-fold; P < 0.05). Kinetic analysis showed a similar Michaelis constant (K(m); 50.8 +/- 5.3 microM) and maximum velocity (3.3 +/- 0.4 pmol/10(6) cells.min) for ascorbic acid transport in FSH-, 8Br-cAMP-, or phorbol ester-treated cells. Ouabain (100 microM) or removal of extracellular Na+ significantly inhibited ascorbic acid uptake, as did dinitrophenol (1 mM), an inhibitor of mitochondrial production of ATP. The induction of ascorbic acid transport by FSH, IGF-I, or GnRH was abolished by simultaneous incubation with tyrphostin (AG-18; 80 microM), a specific tyrosine kinase inhibitor, whereas induction was unaffected by an inactive, but chemically similar, compound (A-1; 80 microM). From these results we conclude that ascorbic acid uptake is energy and Na+ dependent and that the induction of ascorbic acid transporters in granulosa cells occurs through multiple hormones that ultimately influence tyrosine-specific protein kinases. The hormone-dependent induction of ascorbic acid accumulation in granulosa cells appears to be an essential process for the development and maintenance of a viable follicle.

(PDF emailed within 0-6 h: $19.90)

Accession: 002860202

Download citation: RISBibTeXText

PMID: 8828491

DOI: 10.1210/endo.137.10.8828491



Related references

Dehydroascorbic acid transport is hormone regulated in immature rat granulosa cells. Biology of Reproduction 56(SUPPL 1): 126, 1997

Hormone-regulated and glucose-sensitive transport of dehydroascorbic acid in immature rat granulosa cells. Endocrinology 140(8): 3659-3665, 1999

Hormonal regulation of tissue-type plasminogen activator messenger ribonucleic acid levels in rat granulosa cells: mechanisms of induction by follicle-stimulating hormone and gonadotropin releasing hormone. Molecular Endocrinology 2(9): 854-861, 1988

Effect of high and low molecular weight fractions of porcine follicular fluid from small medium and large follicles on the induction of luteinizing hormone human chorionic gonadotropin receptors in immature granulosa cells from the pig. Greenwald, G S And P F Terranova (Ed ) Factors Regulating Ovarian Function; 4th Biennial Ovarian Workshop, Madison, Wis , Usa, July 17-19, 1982 Xxv+481p Raven Press: New York, N Y , Usa Illus P185-190, 1983

Follicle-stimulating hormone induction of luteinizing hormone receptor in cultured rat granulosa cells: an examination of the need for steroids in the induction process. Endocrinology 108(4): 1379-1385, 1981

Effect of a pregnant mare serum gonadotropin on the induction and degradation of fsh and luteinizing hormone receptors in the granulosa cell of the immature rat. Molecular & Cellular Endocrinology 37(2): 215-222, 1984

Direct inhibitory effect of gonadotropin-releasing hormone upon follicle-stimulating hormone induction of luteinizing hormone receptor and aromatase activity in rat granulosa cells. Endocrinology 106(6): 1697-1705, 1980

Anti-Müllerian hormone recruits BMPR-IA in immature granulosa cells. Plos One 8(11): E81551-E81551, 2014

Induction of receptor for luteinizing hormone in rat granulosa cells in vivo and in vitro by follicle stimulating hormone. Drummond, George I , Paul Greengard And G Alan Robison (Ed ) Advances in Cyclic Nucleotide Research, Vol 5 Second International Conference Vancouver, B C , Canada, July 8-11, 1974 Xiii+872p Illus Raven Press, Publishers: New York, N Y , U S A Isbn 0-89004-021-4 803, 1975

Somatomedin-C enhances induction of luteinizing hormone receptors by follicle-stimulating hormone in cultured rat granulosa cells. Endocrinology 116(6): 2369-2375, 1985

Hormone induction of progesterone receptor (PR) messenger ribonucleic acid and activation of PR promoter regions in ovarian granulosa cells: evidence for a role of cyclic adenosine 3',5'-monophosphate but not estradiol. Molecular Endocrinology 12(8): 1201-1214, 1998

Effects of luteinizing hormone and follicle-stimulating hormone on the progesterone receptor induction in chicken granulosa cells in vivo. Poultry Science 74(1): 147-151, 1995

Induction of amino acid transport by L-triiodothyronine in cultured growth hormone-producing rat pituitary tumor cells (GC cells). Journal of Biological Chemistry 259(9): 5726-5733, 1984

Follicle stimulating hormone induction of functional luteinizing hormone receptors in rat granulosa cells cultured in a chemically defined medium. Nature (London) 279(5711): 336-338, 1979

Estrogens enhance the adenosine 3',5'-monophosphate-mediated induction of follicle-stimulating hormone and luteinizing hormone receptors in rat granulosa cells. Endocrinology 115(1): 41-49, 1984