Expression and Contribution of Three Different Isoforms of Prostaglandin E Synthase in the Bovine Endometrium

• Published in: Biology of reproduction Vol. 73; no. 1; pp. 36 - 44
• Main Authors: PARENT, Julie, FORTIER, Michel A
• Format: Journal Article
• Language: English
• Published: Madison, WI Society for the Study of Reproduction 01-07-2005
• Subjects: Amino Acid Sequence; Animals; Base Sequence; Biological and medical sciences; Blotting, Western - veterinary; Bos; Cattle - metabolism; Cloning, Molecular; Endometrium - enzymology; Estrous Cycle - physiology; Female; Fundamental and applied biological sciences. Psychology; Immunohistochemistry - veterinary; Intramolecular Oxidoreductases - biosynthesis; Intramolecular Oxidoreductases - genetics; Intramolecular Oxidoreductases - metabolism; Isoenzymes - biosynthesis; Isoenzymes - genetics; Isoenzymes - metabolism; Mammalian female genital system; Molecular Sequence Data; Morphology. Physiology; Prostaglandin-E Synthases; Reverse Transcriptase Polymerase Chain Reaction - veterinary; RNA, Messenger - biosynthesis; RNA, Messenger - genetics; Sequence Analysis, DNA; Vertebrates: reproduction; Molecular form; Intramolecular oxidoreductases; mechanisms of hormone action; Ox; Biosynthesis; EC 5.3.99.3; Reproduction; Isomerases; Uterus; Eicosanoid; Female genital system; Female; Mechanism of action; Ungulata; Endometrium; Hormone; Prostaglandin; Enzyme; Arachidonic acid derivatives; Prostaglandin-E synthase; Pregnancy; Vertebrata; Mammalia; establishment of pregnancy; Ovulatory cycle; prostaglandin biosynthesis; Animal; bovine; Artiodactyla; female reproductive tract
• ISSN: 0006-3363; 1529-7268
• DOI: 10.1095/biolreprod.104.037036

Prostaglandins are involved in the regulation of several reproductive processes such as ovulation, luteolysis, and establishment
of pregnancy. Prostaglandin E 2 (PGE 2 ) appears to favor establishment of pregnancy in most mammals studied so far. The primary enzymes involved in the production
of PGE 2 from arachidonic acid are cyclooxygenases and prostaglandin E synthases (PGES). Three PGES have been identified in humans,
but in the bovine, microsomal PGES2 and cytosolic PGES genes have neither been cloned nor associated to any physiological processes. The present study was undertaken to clone bovine
MPGES2 and CPGES and to report on their regulation in the endometrium during the estrous cycle. CPGES mRNA expression declines progressively during the cycle; its protein is not modulated according to a precise pattern. MPGES2 mRNA and protein expression decrease from the beginning of the cycle until Days 13–15 and then increase until ovulation.
Immunohistochemical analysis reveals that both enzymes are located in luminal epithelial and glandular epithelial cells and
at a lower level in stromal cells. In addition, using the bovine endometrial cell line BEND, where higher accumulation of
PGE 2 is observed following treatment with phorbol 12-myristate 13-actetate (PMA) and tumor necrosis factor-α (TNF-α), we have
found an associated increase of MPGES1 and COX2 but not CPGES or MPGES2 protein expression. Together, our results suggest that MPGES1 is not the only PGES present in the bovine endometrium but is the main enzyme associated with increased PGE 2 production in vitro.
Abstract
Cloning and functional expression in vivo and in vitro of the different isoforms of Prostaglandin E synthases responsible
for PGE 2 production in the endometrium