Cyclooxygenase 2 messenger RNA levels in canine follicular cells: interrelationship with GDF-9, BMP-15, and progesterone

M De Los Reyes; J Palomino; A Araujo; J Flores; G Ramirez; V H Parraguez; K Aspee

doi:10.1016/j.domaniend.2020.106529

Cyclooxygenase 2 messenger RNA levels in canine follicular cells: interrelationship with GDF-9, BMP-15, and progesterone

Domest Anim Endocrinol. 2021 Jan:74:106529. doi: 10.1016/j.domaniend.2020.106529. Epub 2020 Aug 6.

Authors

M De Los Reyes¹, J Palomino², A Araujo², J Flores², G Ramirez², V H Parraguez³, K Aspee²

Affiliations

¹ Laboratory of Animal Reproduction, Department of Animal Production, Faculty of Veterinary Sciences, University of Chile, Santa Rosa 11735, La Pintana, Santiago, Chile. Electronic address: mdlreyes@uchile.cl.
² Laboratory of Animal Reproduction, Department of Animal Production, Faculty of Veterinary Sciences, University of Chile, Santa Rosa 11735, La Pintana, Santiago, Chile.
³ Laboratory of Animal Physiology, Department of Biological Sciences, Faculty of Veterinary Sciences, University of Chile, Santa Rosa, 11735, La Pintana, Santiago, Chile.

PMID: 32890884
DOI: 10.1016/j.domaniend.2020.106529

Abstract

Cyclooxygenase 2 (COX-2) encoded by the Cox-2 gene within the periovulatory follicles is a critical mediator of oocyte development. Growth differentiation factor 9 (GDF-9) and bone morphogenetic protein 15 (BMP-15) participate in the modulation of certain target genes in the ovary, possibly influencing the Cox-2 gene expression. However, this relationship has not been characterized in canines. This study aimed to examine the possible relationships among BMP-15, GDF-9, progesterone, and Cox-2 gene expression in granulosa-cumulus cells in dogs. Granulosa cells from antral follicles and their corresponding cumulus-oocyte complexes and follicular fluid (FF) were separately obtained from 56 ovaries collected from adult bitches at estrus (n = 15) and proestrus (n = 13) after ovariohysterectomy. Total RNA extraction was performed in follicular cells, and Cox-2 gene expression was assessed by quantitative PCR analysis. Progesterone, BMP-15, and GDF-9 were determined in the FF samples using ELISA assays. Cumulus-oocyte complexes were subjected to in vitro maturation (IVM) with or without (control) recombinant GDF-9 and BMP-15. After 72 h of culture, Cox-2 transcript analyses were performed in cumulus cells via quantitative PCR. Data were evaluated by ANOVA. An increase (P < 0.05) in Cox-2 messenger RNA levels was observed in follicular cells from follicles at estrus with respect to those at proestrus. However, the levels of BMP-15 and GDF-9 in FF decreased (P < 0.05), whereas progesterone increased (P < 0.05) from the proestrus phase to the estrus phase. The expression of Cox-2 gene in cumulus cells was 4-fold greater (P < 0.01) than that in the control when both growth factors were added to the IVM culture. In conclusion, although BMP-15 together with GDF-9 appears to upregulate the levels of Cox-2 transcripts during IVM, the inverse relationship of these paracrine factors with Cox-2 gene expression and the positive correlation of progesterone with Cox-2 transcripts suggest that the high progesterone levels could be more relevant in the local mechanisms regulating the Cox-2 gene expression.

Keywords: Cox-2; Dog; Follicle; Paracrine factors; Progesterone.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Bone Morphogenetic Protein 15 / genetics
Bone Morphogenetic Protein 15 / metabolism*
Cyclooxygenase 2 / genetics
Cyclooxygenase 2 / metabolism*
Dogs*
Estrous Cycle / physiology
Female
Growth Differentiation Factor 9 / genetics
Growth Differentiation Factor 9 / metabolism*
Ovarian Follicle / metabolism*
Progesterone / blood
Progesterone / metabolism*
RNA, Messenger / genetics
RNA, Messenger / metabolism*

Substances

Bone Morphogenetic Protein 15
Growth Differentiation Factor 9
RNA, Messenger
Progesterone
Cyclooxygenase 2