Decidual cells and decidualization in the carnivoran endotheliochorial placenta

DIESSLER, MÓNICA ELIZABETH; HERNÁNDEZ, ROCÍO; GOMEZ CASTRO, GIMENA; BARBEITO, CLAUDIO GUSTAVO

Frontiers in Cell and Developmental Biology

Frontiers

Año: 2023 vol. 11

Decidualization is considered a distinctive feature of eutherian pregnancy, and hasappeared during evolution along with the development of invasive forms ofplacentation, as the endotheliochorial placenta. Although decidualization is notmassive in carnivores, as it is in most species developing hemochorial placentas,isolated or grouped cells regarded as decidual have been documented andcharacterized, mainly in bitches and queens. For the majority of the remainingspecies of the order, data in the bibliography are fragmentary. In this article,general morphological aspects of decidual stromal cells (DSCs), their time ofappearance and lasting, data about the expression of cytoskeletal proteins andmolecules considered as markers of decidualization were reviewed. From the datareviewed, it follows that carnivoran DSCs take part either in the secretion ofprogesterone, prostaglandins, relaxin, among other substances, or at least in thesignaling pathways triggered by them. Beyond their physiological roles, some ofthose molecules are already being used, or are yet under study, for the noninvasiveendocrine monitoring and reproductive control of domestic and wildcarnivores. Only insulin-like growth factor binding protein 1, among the maindecidual markers, has been undoubtedly demonstrated in both species. Laminin,on the contrary, was found only in feline DSCs, and prolactin was preliminaryreported in dogs and cats. Prolactin receptor, on the other hand, was found in bothspecies. While canine DSCs are the only placental cell type expressing the nuclearprogesterone receptor (PGR), that receptor has not been demonstrated neither infeline DSCs, nor in any other cell in the queen placenta, although the use of PGRblockers leads to abortion. Against this background, and from the data gathered sofar, it is unquestionable that DSCs in carnivorans do play a pivotal role in placentaldevelopment and health. The knowledge about placental physiology is critical formedical care and breeding management, primarily in domestic carnivores; it is alsoabsolutely crucial for a conservation approach in the management of endangeredcarnivore species.