In:
Experimental Biology and Medicine, SAGE Publications, Vol. 230, No. 5 ( 2005-05), p. 326-333
Abstract:
Prostaglandins (PGs) are known to modulate the proper cycllcity of bovine reproductive organs. The main luteolytlc agent in ruminants Is PGF 2α , whereas PGE 2 has luteotropic actions. Estradiol 17ß (E 2 ) regulates uterus function by influencing PG synthesis. Phytoestrogens structurally resemble E 2 and possess estrogenic activity; therefore, they may mimic the effects of E 2 on PG synthesis and influence the reproductive system. Using a cell-culture system of bovine epithelial and stromal cells, we determined cell-specific effects of phytoestrogens (i.e., daidzein, genistein), their metabolites (i.e., equol and para-ethyl-phenol, respectively), and E 2 on PGF 2α and PGE 2 synthesis and examined the intracellular mechanisms of their actions. Both PGs produced by stromal and epithelial cells were significantly stimulated by phytoestrogens and their metabolites. However, PGF 2α synthesis by both kinds of cells was greater stimulated than PGE 2 synthesis. Moreover, epithelial cells treated with phytoestrogens synthesized more PGF 2α than stromal cells, increasing the PGF 2α , to PGE 2 ratio. The epithelial and stromal cells were prelncubated with an estrogen-receptor (ER) antagonist (i.e., ICI), a transiation inhibitor (i.e., actinomycin D), a protein kinase A inhibitor (i.e., staurosporin), and a phospholipase C inhibitor (i.e., U73122) for 0.5 hrs and then stimulated with equol, para-ethyl-phenol, or E 2- Although the action of E 2 on PGF 2α synthesis was blocked by all reagents, the stimulatory effect of phytoestrogens was blocked only by ICI and actinomycin D in both cell types. Moreover, in contrast to E 2 action, phytoestrogens did not cause Intracellular calcium mobilization in either epithelial or stromal cells. Phytoestrogens stimulate both PGF 2α and PGE 2 in both cell types of bovine endometrium via an ER-dependent genomic pathway. However, because phytoestrogens preferentially stimulated PGF 2α synthesis in epithelial cells of bovine endometrium, they may disrupt uterus function by altering the PGF 2α to PGE 2 ratio.
Type of Medium:
Online Resource
ISSN:
1535-3702
,
1535-3699
DOI:
10.1177/153537020523000506
Language:
English
Publisher:
SAGE Publications
Publication Date:
2005
detail.hit.zdb_id:
2020856-X
SSG:
12
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